Accuracy in equianalgesic dosing. conversion dilemmas

Balanced opioid-free anesthesia with lidocaine and esketamine versus balanced anesthesia with sufentanil for gynecological endoscopic surgery: a randomized controlled trial

In this randomized controlled trial, 74 patients scheduled for gynecological laparoscopic surgery (American Society of Anesthesiologists grade I/II) were enrolled and randomly divided into two study groups: (i) Group C (control), received sufentanil (0.3 μg/kg) and saline, followed by sufentanil (0.1 μg/kg∙h) and saline; and (ii) Group F (OFA), received esketamine (0.15 mg/kg) and lidocaine (2 mg/kg), followed by esketamine (0.1 mg/kg∙h) and lidocaine (1.5 mg/kg∙h). The primary outcome was the 48-h time-weighted average (TWA) of postoperative pain scores. Secondary outcomes included time to extubation, adverse effects, and postoperative sedation score, pain scores at different time points, analgesic consumption at 48 h, and gastrointestinal functional recovery. The 48-h TWAs of pain scores were 1.32 (0.78) (95% CI 1.06-1.58) and 1.09 (0.70) (95% CI 0.87-1.33) for Groups F and C, respectively. The estimated difference between Groups F and C was - 0.23 (95% CI - 0.58 - 0.12; P = 0.195). No differences were found in any of the secondary outcomes and no severe adverse effects were observed in either group. Balanced OFA with lidocaine and esketamine achieved similar effects to balanced anesthesia with sufentanil in patients undergoing elective gynecological laparoscopic surgery, without severe adverse effects.Clinical Trial Registration: ChiCTR2300067951, www.chictr.org.cn 01 February, 2023.

Postoperative pain scores and opioid use after standard bupivacaine vs. liposomal bupivacaine regional blocks for abdominal cancer surgery: A propensity score matched study

BACKGROUND

Fascial plane blocks (FPBs) are widely used for abdominal surgery with the assumption that liposomal bupivacaine (LB) is more effective than standard bupivacaine (SB).

METHODS

This was a single-institution retrospective cohort study of patients administered FPBs with LB or SB ​+ ​admixtures (dexamethasone/dexmedetomidine) for open abdominal cancer surgery. Propensity score matching generated a 2:1 (LB:SB) matched cohort. Opioid use (mg oral morphine equivalents, OME) and severe pain (≥3 pain scores ≥7 in a 24-h period) were compared.

RESULTS

Opioid use was >150 ​mg OME in 19.9 ​% (29/146) LB and 16.4 ​% (12/73) SB patients (p ​= ​0.586). Severe pain was experienced by 44 ​% (64/146) LB and 53 ​% (39/73) SB patients (p ​= ​0.198). On multivariable analysis, SB vs LB choice was not associated with high opioid volume >150 ​mg or severe pain.

CONCLUSIONS

FPBs with standard bupivacaine were not associated with higher 72-h opioid use or more severe pain compared to liposomal bupivacaine.

Combined erector spinae plane block with surgical intercostal nerve cryoablation for Nuss procedure is associated with decreased opioid use and length of stay

BACKGROUND AND OBJECTIVES

Pain management for patients undergoing the Nuss procedure for treatment of pectus excavatum can be challenging. In an effort to improve pain management, our institution added bilateral single injection erector spinae plane (ESP) blocks to surgeon placed intercostal nerve cryoablation. We aimed to assess the efficacy of this practice change.

METHODS

Retrospective clinical data from a single academic medical center were evaluated. Due to an institutional change in clinical management, we were able to perform a before and after study. Twenty patients undergoing Nuss procedure who received bilateral ultrasound-guided single-shot T6 level ESP blocks and intercostal nerve cryoablation were compared with a historical control cohort of 20 patients who underwent Nuss procedure with intercostal nerve cryoablation alone. The primary outcome variables included postoperative pain scores, total hospital opioid use, and hospital length of stay.

RESULTS

Median total hospital intravenous morphine milligram equivalents was lower for the ESP group than for the control group (0.60 (IQR 0.35-0.88) vs 1.15 mg/kg (IQR 0.74-1.68), p<0.01). There was no difference in postoperative pain scores between the two groups. Mean hospital length of stay was 2.45 (SD 0.69) days for the control group and 1.95 (SD 0.69) days for the ESP group (p=0.03). No adverse events related to block placement were identified.

CONCLUSIONS

In a single-center academic practice, the addition of bilateral single injection ESP blocks at T6 to surgeon performed cryoablation reduced opioid consumption without a change in subjectively reported pain scores. The results from this pilot study can provide effect size estimates to guide the design of future randomized trials.

Conversion ratios: Why is it so challenging to construct opioid conversion tables?

Standardizing opioid management is challenging due to the absence of a ceiling dose, the unknown ideal therapeutic plasma level, and the lack of an clear relationship between dose and therapeutic response. Opioid rotation or conversion, which is switching from one opioid, route of administration, or both, to another, to improve therapeutic response and reduce toxicities, occurs in 20-40 percent of patients treated with opioids. Opioid conversion is often needed when there are adverse effects, toxicities, or inability to tolerate a certain opioid formulation. A majority of patients benefit from opioid conversion, leading to improved analgesia and less adverse effects. There are different published ways of converting opioids in the literature. This review of 20 years of literature is centered on opioid conversions and aims to discuss the complexity of converting opioids. We discuss study designs, outcomes and measures, pain phenotypes, patient characteristics, comparisons of equivalent doses between opioids, reconciling conversion ratios between opioids, routes, directional differences, half-lives and metabolites, interindividual variability, and comparison to package insert information. Palliative care specialists have not yet come to a consensus on the ideal opioid equianalgesic table; however, we discuss a recently updated table, based on retrospective evidence, that may serve as a gold standard for practical use in the palliative care population. More robust, well-designed studies are needed to validate and guide future opioid conversion data.

Comparisons of fentanyl and sufentanil on recovery time after inguinal hernia repair in children: a randomized clinical trial

BACKGROUND

Inguinal hernia repair is a common pediatric procedure. We studied postoperative recovery times in children undergoing laparoscopic inguinal hernia repair with anesthesia induced by fentanyl versus sufentanil.

METHODS

We performed a pilot randomized clinical trial between February and December 2022. Eligible children were assigned into two age groups, 2-6 and 6-12 years old groups. Then, children in each age group were randomly assigned into either the fentanyl (2 µg/kg) or sufentanil (0.2 µg/kg) group for anesthesia induction. Baseline characteristics were collected. The primary outcome was the postoperative recovery time, which was recorded as the time period from extubation to a Steward recovery score reaching 6. Secondary outcomes included surgical duration, anesthetic duration, intubation duration, and intraoperative hemorrhage.

RESULTS

There were 300 children, with 75 children in each group. In the 2-6 years old group, children who received fentanyl had statistically significantly shorter postoperative recovery times than children who received sufentanil (0.9 ± 0.4 versus 1.5 ± 0.3 h, P < 0.001). However, in the 6-12 years old group, children who received fentanyl had statistically significantly longer postoperative recovery times than children who received sufentanil (1.2 ± 0.4 versus 0.8 ± 0.4 h, P < 0.001). Baseline characteristics and secondary outcomes were comparable between two groups.

CONCLUSIONS

Anesthesia induction with fentanyl or sufentanil resulted in different postoperative recovery times after laparoscopic inguinal hernia repair in children in different age groups. More studies are required to determine the appropriate induction anesthetic in children of different ages.

TRIAL REGISTRATION

The study protocol was retrospectively registered online at the Chinese Clinical Trial Registry (registration number ChiCTR2300072177, retrospectively registered on 06/06/2023).

Variation in Intraoperative Opioid Administration by Patient, Clinician, and Hospital Contribution

Importance

The opioid crisis has led to scrutiny of opioid exposures before and after surgical procedures. However, the extent of intraoperative opioid variation and the sources and contributing factors associated with it are unclear.

Objective

To analyze attributable variance of intraoperative opioid administration for patient-, clinician-, and hospital-level factors across surgical and analgesic categories.

Design, Setting, and Participants

This cohort study was conducted using electronic health record data collected from a national quality collaborative database. The cohort consisted of 1 011 268 surgical procedures at 46 hospitals across the US involving 2911 anesthesiologists, 2291 surgeons, and 8 surgical and 4 analgesic categories. Patients without ambulatory opioid prescriptions or use history undergoing an elective surgical procedure between January 1, 2014, and September 11, 2020, were included. Data were analyzed from January 2022 to July 2023.

Main Outcomes and Measures

The rate of intraoperative opioid administration as a continuous measure of oral morphine equivalents (OMEs) normalized to patient weight and case duration was assessed. Attributable variance was estimated in a hierarchical structure using patient, clinician, and hospital levels and adjusted intraclass correlations (ICCs).

Results

Among 1 011 268 surgical procedures (mean [SD] age of patients, 55.9 [16.2] years; 604 057 surgical procedures among females [59.7%]), the mean (SD) rate of intraoperative opioid administration was 0.3 [0.2] OME/kg/h. Together, clinician and hospital levels contributed to 20% or more of variability in intraoperative opioid administration across all analgesic and surgical categories (adjusting for surgical or analgesic category, ICCs ranged from 0.57-0.79 for the patient, 0.04-0.22 for the anesthesiologist, and 0.09-0.26 for the hospital, with the lowest ICC combination 0.21 for anesthesiologist and hosptial [0.12 for the anesthesiologist and 0.09 for the hospital for opioid only]). Comparing the 95th and fifth percentiles of opioid administration, variation was 3.3-fold among anesthesiologists (surgical category range, 2.7-fold to 7.7-fold), 4.3-fold among surgeons (surgical category range, 3.4-fold to 8.0-fold), and 2.2-fold among hospitals (surgical category range, 2.2-fold to 4.3-fold). When adjusted for patient and surgical characteristics, mean (square error mean) administration was highest for cardiac surgical procedures (0.54 [0.56-0.52 OME/kg/h]) and lowest for orthopedic knee surgical procedures (0.19 [0.17-0.21 OME/kg/h]). Peripheral and neuraxial analgesic techniques were associated with reduced administration in orthopedic hip (51.6% [95% CI, 51.4%-51.8%] and 60.7% [95% CI, 60.5%-60.9%] reductions, respectively) and knee (48.3% [95% CI, 48.0%-48.5%] and 60.9% [95% CI, 60.7%-61.1%] reductions, respectively) surgical procedures, but reduction was less substantial in other surgical categories (mean [SD] reduction, 13.3% [8.8%] for peripheral and 17.6% [9.9%] for neuraxial techniques).

Conclusions and Relevance

In this cohort study, clinician-, hospital-, and patient-level factors had important contributions to substantial variation of opioid administrations during surgical procedures. These findings suggest the need for a broadened focus across multiple factors when developing and implementing opioid-reducing strategies in collaborative quality-improvement programs.

Application of Butorphanol versus Sufentanil in Multimode Analgesia via Patient Controlled Intravenous Analgesia After Hepatobiliary Surgery: A Retrospective Cohort Study

Purpose

We investigate the efficacy and safety of butorphanol in multimodal analgesia combined with dexmedetomidine and ketorolac via patient-controlled intravenous analgesia (PCIA) after hepatobiliary surgery, as compared with sufentanil.

Patients and Methods

Postoperative follow-up data of hepatobiliary surgery patients in Henan Provincial People's Hospital from March 2018 to June 2021 were collected retrospectively and divided into butorphanol group (group B) or sufentanil group (group S) according to the postoperative intravenous controlled analgesia scheme. The baseline characteristics and surgical information of the two groups were matched through propensity score matching (PSM).

Results

A total of 3437 patients were screened, and PSM yielded 1816 patients after matching, including 908 in the butorphanol group and 908 in the sufentanil group. Compared with group S, the incidence of moderate-to-severe pain on the first postoperative day and the second postoperative day was lower in group B during rest (3.2% vs 10.9%, P<0.001; 1.2% vs 4.6%, P<0.001), and during movement (7.0% vs 18.9%, P<0.001; 2.6% vs 8.7%, P<0.001). Patients receiving butorphanol had a lower morphine consumption (50mg vs 120mg, P<0.001). The bolus attempts of an analgesic pump in group B were significantly lower than in group S (1 vs 2, P<0.001). Postoperative hospital length of stay was shortened in group B (11d vs 12d, P=0.017). The occurrence of postoperative vomiting was lower in group B (1.4% vs 3.0%, P=0.025) than in group S. However, more patients in group B experienced dizziness (0.9% vs 0.1%, P=0.019).

Conclusion

Compared with sufentanil, the application of butorphanol in multimodal analgesia combined with dexmedetomidine and ketorolac via PCIA ameliorated postoperative pain after hepatobiliary surgery, with reduced opioid consumption and shorter postoperative hospital length of stay.

Relationship Between Pain and Delirium in Critically Ill Adults

OBJECTIVES

Although opioids are frequently used to treat pain, and are an important risk for ICU delirium, the association between ICU pain itself and delirium remains unclear. We sought to evaluate the relationship between ICU pain and delirium.

DESIGN

Prospective cohort study.

SETTING

A 32-bed academic medical-surgical ICU.

PATIENTS

Critically ill adults (n = 4,064) admitted greater than or equal to 24 hours without a condition hampering delirium assessment.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Daily mental status was classified as arousable without delirium, delirium, or unarousable. Pain was assessed six times daily in arousable patients using a 0-10 Numeric Rating Scale (NRS) or the Critical Care Pain Observation Tool (CPOT); daily peak pain score was categorized as no (NRS = 0/CPOT = 0), mild (NRS = 1-3/CPOT = 1-2), moderate (NRS = 4-6/CPOT = 3-4), or severe (NRS = 7-10/CPOT = 5-8) pain. To address missingness, a Multiple Imputation by Chained Equations approach that used available daily pain severity and 19 pain predictors was used to generate 25 complete datasets. Using a first-order Markov model with a multinomial logistic regression analysis, that controlled for 11 baseline/daily delirium risk factors and considered the competing risks of unarousability and ICU discharge/death, the association between peak daily pain and next-day delirium in each complete dataset was evaluated.

RESULTS

Among 14,013 ICU days (contributed by 4,064 adults), delirium occurred on 2,749 (19.6%). After pain severity imputation on 1,818 ICU days, mild, moderate, and severe pain were detected on 2,712 (34.1%), 1,682 (21.1%), and 894 (11.2%) of the no-delirium days, respectively, and 992 (36.1%), 513 (18.6%), and 27 (10.1%) of delirium days (p = 0.01). The presence of any pain (mild, moderate, or severe) was not associated with a transition from awake without delirium to delirium (aOR 0.96; 95% CI, 0.76-1.21). This association was similar when days with only mild, moderate, or severe pain were considered. All results were stable after controlling for daily opioid dose.

CONCLUSIONS

After controlling for multiple delirium risk factors, including daily opioid use, pain may not be a risk factor for delirium in the ICU. Future prospective research is required.

Opioid-Free Discharge After Pancreatic Resection Through a Learning Health System Paradigm

Importance

Postoperative opioid overprescribing leads to persistent opioid use and excess pills at risk for misuse and diversion. A learning health system paradigm using risk-stratified pancreatectomy clinical pathways (RSPCPs) may lead to reduction in inpatient and discharge opioid volume.

Objective

To analyze the outcomes of 2 iterative RSPCP updates on inpatient and discharge opioid volumes.

Design, Setting, and Participants

This cohort study included 832 consecutive adult patients at an urban comprehensive cancer center who underwent pancreatic resection between October 2016 and April 2022, comprising 3 sequential pathway cohorts (version [V] 1, October 1, 2016, to January 31, 2019 [n = 363]; V2, February 1, 2019, to October 31, 2020 [n = 229]; V3, November 1, 2020, to April 30, 2022 [n = 240]).

Exposures

After V1 of the pathway established a baseline and reduced length of stay (n = 363), V2 (n = 229) updated patient and surgeon education handouts, limited intravenous opioids, suggested a 3-drug (acetaminophen, celecoxib, methocarbamol) nonopioid bundle, and implemented the 5×-multiplier (last 24-hour oral morphine equivalents [OME] multiplied by 5) to calculate discharge volume. Pathway version 3 (n = 240) required the nonopioid bundle as default in the recovery room and scheduled conversion to oral medications on postoperative day 1.

Main Outcomes and Measures

Inpatient and discharge opioid volume in OME across the 3 RSPCPs were compared using nonparametric testing and trend analyses.

Results

A total of 832 consecutive patients (median [IQR] age, 65 [56-72] years; 410 female [49.3%] and 422 male [50.7%]) underwent 541 pancreatoduodenectomies, 285 distal pancreatectomies, and 6 other pancreatectomies. Early nonopioid bundle administration increased from V1 (acetaminophen, 320 patients [88.2%]; celecoxib or anti-inflammatory, 98 patients [27.0%]; methocarbamol, 267 patients [73.6%]) to V3 (236 patients [98.3%], 163 patients [67.9%], and 238 patients [99.2%], respectively; P < .001). Total inpatient OME decreased from a median 290 mg (IQR, 157-468 mg) in V1 to 184 mg (IQR, 103-311 mg) in V2 to 129 mg (IQR, 75-206 mg) in V3 (P < .001). Discharge OME decreased from a median 150 mg (IQR, 100-225 mg) in V1 to 25 mg (IQR, 0-100 mg) in V2 to 0 mg (IQR, 0-50 mg) in V3 (P < .001). The percentage of patients discharged opioid free increased from 7.2% (26 of 363) in V1 to 52.5% (126 of 240) in V3 (P < .001), with 187 of 240 (77.9%) in V3 discharged with 50 mg OME or less. Median pain scores remained 3 or lower in all cohorts, with no differences in postdischarge refill requests. A subgroup analysis separating open and minimally invasive surgical cases showed similar results in both groups.

Conclusions and Relevance

In this cohort study, the median total inpatient OME was halved and median discharge OME reduced to zero in association with a learning health system model of iterative opioid reduction that is freely adaptable by other hospitals. These findings suggest that opioid-free discharge after pancreatectomy and other major cancer operations is realistic and feasible with this no-cost blueprint.

Postoperative Opioid Use Is Associated with Increased Rates of Grade B/C Pancreatic Fistula After Distal Pancreatectomy

BACKGROUND

Clinically relevant postoperative pancreatic fistula (CR-POPF) is a major source of morbidity after distal pancreatectomy. This study examined the association between postoperative opioid use and CR-POPF in the context of opioid-sparing postoperative care.

METHODS

A case-control study was performed on consecutive patients who underwent distal pancreatectomy between October 2016 and April 2022 at a single institution. Patients who developed CR-POPF were compared to controls. Multivariable regression modeling was used to identify factors associated with CR-POPF.

RESULTS

A total of 281 patients underwent 187 open, 20 laparoscopic, and 74 robotic-assisted operations. The rate of CR-POPF was 21% (n = 58). CR-POPF rate declined from 32 to 8% over the study period (p < 0.001). Median oral morphine equivalents (OME) administered on POD 0-1 and 0-3 were 94 and 129 mg, respectively, in patients who did not develop a fistula versus 130 and 180 mg in those who did (both p ≤ 0.001). POD 0-3 OME (OR 1.11, p = 0.044) was independently associated with increased odds of CR-POPF, with each additional 50 mg (equivalent to 10 tramadol pills) increasing the relative risk by 11% and absolute risk by 2%.

CONCLUSION

Early postoperative opioid use after distal pancreatectomy was associated with increased odds of CR-POPF. Decreasing perioperative opioid use through enhanced postoperative management is a low-cost and generalizable approach that may reduce rates of CR-POPF after distal pancreatectomy.

Analgesic Patterns and Opioid Administration in Children Hospitalized With Acute Pancreatitis

BACKGROUND

Pain is the most common symptom of acute pancreatitis (AP), and opioids have been utilized as the cornerstone of treatment. Despite the adverse effects of opioids, data on effective analgesia in children with AP is lacking. We aimed to evaluate analgesia prescribing patterns in pediatric AP, identify factors associated with opioid administration, and test the associations between opioid administration and hospital length of stay (LOS).

METHODS

This is a retrospective cohort study of pediatric AP hospitalizations in a single institution from 2010 to 2020. Opioid administration was calculated for the first 48 hours of admission (morphine milligram equivalent; MME48). Data on multimodal analgesia [defined as the administration of acetaminophen and nonsteroidal anti-inflammatory drugs (NSAIDs)] during hospitalization was captured.

RESULTS

The sample included 224 patients, mean age 12.0 years (standard deviation = 4.9) and 58.9% female. Median LOS was 4 days (interquartile range 2-9). Most patients (71.4%) were prescribed opioids, 77.7% acetaminophen, 40.2% NSAIDs, and 37.5% multimodal analgesia. Opioid administration decreased over the study period; in contrast, there was an increase in multimodal analgesia administration. Opioid administration did not differ by sex, age, biliary versus non-biliary etiology, or race/ethnicity. In a multivariate regression model, lower albumin values ( P < 0.01) and younger age ( P < 0.05) were significant predictors of increased LOS, while MME48 was not associated with increased LOS.

CONCLUSIONS

Opioids were commonly administered; only 37.5% of children were administered multimodal analgesia during their hospitalization for AP. Opioid administration was not associated with increased LOS. Prospective studies are needed to determine optimal pain management for pediatric AP.

New insight into the analgesic recipe: A cohort study based on smart patient-controlled analgesia pumps records

Purpose: Intravenous patient-controlled analgesia (IV-PCA) has been widely used; however, regimen criteria have not yet been established. In China, the most often used opioid is sufentanil, for which repeated doses are a concern, and empirical flurbiprofen axetil (FBP) as an adjuvant. We hypothesized that hydromorphone would be a better choice and also evaluated the effectiveness of FBP as an adjuvant.

Methods: This historical cohort study was conducted in two tertiary hospitals in China and included 12,674 patients using hydromorphone or sufentanil for IV-PCA between April 1, 2017, and January 30, 2021. The primary outcome was analgesic insufficiency at static (AIS). The secondary outcomes included analgesic insufficiency with movement (AIM) and common opioid-related adverse effects such as postoperative nausea and vomiting (PONV) and dizziness.

Results: Sufentanil, but not the sufentanil-FBP combination, was associated with higher risks of AIS and AIM compared to those for hydromorphone (OR 1.64 [1.23, 2.19], p < 0.001 and OR 1.42 [1.16, 1.73], p < 0.001). Hydromorphone combined with FBP also decreased the risk of both AIS and AIM compared to those for pure hydromorphone (OR 0.74 [0.61, 0.90], p = 0.003 and OR 0.80 [0.71, 0.91], p < 0.001). However, the risk of PONV was higher in patients aged ≤35 years using FBP (hydromorphone-FBP vs. hydromorphone and sufentanil-FBP vs. hydromorphone, OR 1.69 [1.22, 2.33], p = 0.001 and 1.79 [1.12, 2.86], p = 0.015).

Conclusion: Hydromorphone was superior to sufentanil for IV-PCA in postoperative analgesia. Adding FBP may improve the analgesic effects of both hydromorphone and sufentanil but was associated with an increased risk of PONV in patients <35 years of age.

Pharmacokinetic modeling and simulation to understand diamorphine dose-response in neonates, children, and adolescents

Pharmacokinetic-pharmacodynamic modeling and simulation can facilitate understanding and prediction of exposure-response relationships in children with acute or chronic pain. The pharmacokinetics of diamorphine (diacetylmorphine, heroin), a strong opioid, remain poorly quantified in children and dose is often guided by clinical acumen. This tutorial demonstrates how a model to describe intranasal and intravenous diamorphine pharmacokinetics can be fashioned from a model for diamorphine disposition in adults and a model describing morphine disposition in children. Allometric scaling and maturation models were applied to clearances and volumes to account for differences in size and age between children and adults. The utility of modeling and simulation to gain insight into the analgesic exposure-response relationship is demonstrated. The model explains reported observations, can be used for interrogation, interpolated to determine equianalgesia and inform future clinical studies. Simulation was used to illustrate how diamorphine is rapidly metabolized to morphine via its active metabolite 6-monoacetylmorphine, which mediates an early dopaminergic response accountable for early euphoria. Morphine formation is then responsible for the slower, prolonged analgesic response. Time-concentration profiles of diamorphine and its metabolites reflected disposition changes with age and were used to describe intravenous and intranasal dosing regimens. These indicated that morphine exposure in children after intranasal diamorphine 0.1 mg.kg-1 was similar to that after intranasal diamorphine 5 mg in adults. A target concentration of morphine 30 μg.L-1 can be achieved by a diamorphine intravenous infusion in neonates 14 μg.kg-1 .h-1 , in a 5-year-old child 42 μg.kg-1 .h-1 and in an 15 year-old-adolescent 33 μg.kg-1 .h-1 .

Analysis of Opioid Use in Patients Undergoing Open Versus Robotic Gastrectomy

BACKGROUND

Minimally invasive, robotic gastrectomy is associated with better short-term outcomes and quicker functional recovery. However, the degree to which the robotic approach influences postoperative pain and opioid use after gastrectomy is unknown. Our primary aim was to determine whether the robotic approach to gastrectomy reduces postoperative opioid use compared with the open approach.

METHODS

Patients who underwent gastrectomy (November 2018 to September 2021) were identified retrospectively. Clinical characteristics, short-term surgical outcomes, oral morphine equivalent (OME) use, and pain scores were collected. Both groups were managed through an enhanced recovery program in the perioperative period.

RESULTS

Of 81 patients, 50 underwent open and 31 underwent robotic gastrectomy. Compared with open gastrectomy patients, robotic gastrectomy patients had longer surgery time (360 vs. 288 min), less blood loss (50 vs. 138 mL), and shorter hospital stay (4 vs. 6 days) (all medians, P < 0.001). Robotic gastrectomy patients used lower OMEs on postoperative days 0-4 (all P < 0.05) and in total for days 0-4 (total mean dose 65.0 vs. 169.5 mg; P < 0.001) than did open gastrectomy patients. The robotic gastrectomy patients were prescribed a lower mean OME dose than the open gastrectomy patients (19.0 vs. 29.0 mg, respectively; P = 0.001). Multivariable analysis showed that robotic approach was associated with lower opioid use (odds ratio 3.70; 95% CI 1.01-14.3; P = 0.049).

CONCLUSIONS

Compared with open gastrectomy, robotic gastrectomy reduces opioid use in the early postoperative period and is associated with fewer OME discharge prescriptions and shorter hospital stay.

Opioid Weaning Protocol Using Morphine Compared With Nonprotocolized Methadone Associated With Decreased Dose and Duration of Opioid After Norwood Procedure

OBJECTIVES

Opioids are used to manage pain, comfort, maintain devices, and decrease oxygen consumption around Norwood palliation (NP), but in high dose and prolonged exposure, they increase risk of tolerance and iatrogenic withdrawal syndrome (IAWS). Variability in practice for IAWS prevention potentially increases opioid dose and duration. We hypothesize that protocolized weaning with morphine (MOR) versus nonprotocolized methadone (MTD) is associated with reduction in opioid exposure.

DESIGN

A before-versus-after study of outcomes of patients weaned with protocolized MOR versus nonprotocolized MTD including subset analysis for those patients with complications postoperatively. Primary endpoints include daily, wean phase, and total morphine milligram equivalent (MMEq) dose, duration, and, secondarily, length of stay (LOS).

SETTING

Quaternary-care pediatric cardiac ICU.

PATIENTS

Neonates undergoing single-ventricle palliation.

INTERVENTIONS

Introduction of IAWS prevention protocol.

MEASUREMENTS AND MAIN RESULTS

Analysis included 54 patients who underwent the NP in 2017-2018 including the subset analysis of 34 who had a complicated postoperative course. The total and wean phase opioid doses for the MTD group were significantly higher than that for the MOR group: 258 versus 22 and 115 versus 6 MMEq/kg; p < 0.001. Duration of opioid exposure was 63 days in the MTD group and 12 days in MOR group (p < 0.001). Subanalysis of the complicated subset also identifies higher total and wean dose for MTD group (293 vs 41 and 116 vs 7 MMEq/kg; p < 0.001) with a longer duration (65 vs 22 days; p = 0.001). Within the subset, LOS was 55% longer in the MTD group than that in the MOR group (150 vs 67 d; p = 0.01) and not different in the uncomplicated group.

CONCLUSIONS

After complex NP, a protocolized opioid weaning using MOR versus MTD is associated with 65% shorter opioid duration, 10-fold decreased dose, and shortened LOS.

Perioperative Low-Dose Ketamine for Postoperative Pain Management in Spine Surgery: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Objective

Although low-dose ketamine has been shown to be generally beneficial in terms of pain control in a variety of major surgery, there is no consensus regarding the effectiveness of supplemental ketamine analgesic use exclusively in spine surgery. The objective of this systematic review and meta-analysis of randomized controlled trials (RCTs) was to assess the efficacy and safety of perioperative low-dose ketamine for pain management and analgesic consumption in patients undergoing spine surgery.

Methods

A comprehensive literature search was performed for relevant studies using PubMed, EMBASE, Web of Science, and Cochrane Library. Patients who received perioperative low-dose ketamine were compared to the control group in terms of postoperative pain intensity, opioid consumption, and adverse events. Patients were further categorized by ages and administration times for subgroup analysis.

Results

A total of 30 RCTs comprising 1,865 patients undergoing elective spine surgery were included. Significantly lower pain intensity and less opioid consumption at 12 h, 24 h, and 48 h postoperatively and lower incidence of postoperative nausea and vomiting (PONV) were observed in the ketamine group (all P < 0.05). There was no significant difference of central nervous system (CNS) adverse events between groups. However, different efficacy of low-dose ketamine was detected when patients were categorized by ages and administration times.

Conclusion

Perioperative low-dose ketamine demonstrated analgesic and morphine-sparing effect with no increased adverse events after spine surgery. However, this effect was not significant in pediatric patients. Only postoperative or intraoperative and postoperative administration could prolong the analgesic time up to 48 h postoperatively. Further studies should focus on the optimal protocol of ketamine administration and its effect on old age participants.

ICU delirium burden predicts functional neurologic outcomes

Background

We investigated the effect of delirium burden in mechanically ventilated patients, beginning in the ICU and continuing throughout hospitalization, on functional neurologic outcomes up to 2.5 years following critical illness.

Methods

Prospective cohort study of enrolling 178 consecutive mechanically ventilated adult medical and surgical ICU patients between October 2013 and May 2016. Altogether, patients were assessed daily for delirium 2941days using the Confusion Assessment Method for the ICU (CAM-ICU). Hospitalization delirium burden (DB) was quantified as number of hospital days with delirium divided by total days at risk. Survival status up to 2.5 years and neurologic outcomes using the Glasgow Outcome Scale were recorded at discharge 3, 6, and 12 months post-discharge.

Results

Of 178 patients, 19 (10.7%) were excluded from outcome analyses due to persistent coma. Among the remaining 159, 123 (77.4%) experienced delirium. DB was independently associated with >4-fold increased mortality at 2.5 years following ICU admission (adjusted hazard ratio [aHR], 4.77; 95% CI, 2.10–10.83; P < .001), and worse neurologic outcome at discharge (adjusted odds ratio [aOR], 0.02; 0.01–0.09; P < .001), 3 (aOR, 0.11; 0.04–0.31; P < .001), 6 (aOR, 0.10; 0.04–0.29; P < .001), and 12 months (aOR, 0.19; 0.07–0.52; P = .001). DB in the ICU alone was not associated with mortality (HR, 1.79; 0.93–3.44; P = .082) and predicted neurologic outcome less strongly than entire hospital stay DB. Similarly, the number of delirium days in the ICU and for whole hospitalization were not associated with mortality (HR, 1.00; 0.93–1.08; P = .917 and HR, 0.98; 0.94–1.03, P = .535) nor with neurological outcomes, except for the association between ICU delirium days and neurological outcome at discharge (OR, 0.90; 0.81–0.99, P = .038).

Conclusions

Delirium burden throughout hospitalization independently predicts long term neurologic outcomes and death up to 2.5 years after critical illness, and is more predictive than delirium burden in the ICU alone and number of delirium days.

Spinal versus general anesthesia for minimally invasive transforaminal lumbar interbody fusion: implications on operating room time, pain, and ambulation

OBJECTIVE

There has been increasing interest in the use of spinal anesthesia (SA) for spine surgery, especially within Enhanced Recovery After Surgery (ERAS) protocols. Despite the wide adoption of SA by the orthopedic practices, it has not gained wide acceptance in lumbar spine surgery. Studies investigating SA versus general anesthesia (GA) in lumbar laminectomy and discectomy have found that SA reduces perioperative costs and leads to a reduction in analgesic use, as well as to shorter anesthesia and surgery time. The aim of this retrospective, case-control study was to compare the perioperative outcomes of patients who underwent minimally invasive surgery (MIS)-transforaminal lumbar interbody fusion (TLIF) after administration of SA with those who underwent MIS-TLIF under GA.

METHODS

Overall, 40 consecutive patients who underwent MIS-TLIF by a single surgeon were analyzed; 20 patients received SA and 20 patients received GA. Procedure time, intraoperative adverse events, postoperative adverse events, postoperative length of stay, 3-hour postanesthesia care unit (PACU) numeric rating scale (NRS) pain score, opioid medication, and time to first ambulation were collected for each patient.

RESULTS

The two groups were homogeneous for clinical characteristics. A decrease in total operating room (OR) time was found for patients who underwent MIS-TLIF after administration of SA, with a mean OR time of 156.5 ± 18.9 minutes versus 213.6 ± 47.4 minutes for patients who underwent MIS-TLIF under GA (p < 0.0001), a reduction of 27%. A decrease in total procedure time was also observed for SA versus GA (122 ± 16.7 minutes vs 175.2 ± 10 minutes; p < 0.0001). No significant differences were found in intraoperative and postoperative adverse events. There was a difference in the mean maximum NRS pain score during the first 3 hours in the PACU as patients who received SA reported a lower pain score compared with those who received GA (4.8 ± 3.5 vs 7.3 ± 2.7; p = 0.018). No significant difference was observed in morphine equivalents received by the two groups. A difference was also observed in the mean overall NRS pain score, with 2.4 ± 2.1 for the SA group versus 4.9 ± 2.3 for the GA group (p = 0.001). Patients who received SA had a shorter time to first ambulation compared with those who received GA (385.8 ± 353.8 minutes vs 855.9 ± 337.4 minutes; p < 0.0001).

CONCLUSIONS

The results of this study have pointed to some important observations in this patient population. SA offers unique advantages in comparison with GA for performing MIS-TLIF, including reduced OR time and postoperative pain, and faster postoperative mobilization.

Does intraoperative and postoperative analgesia cause bile leakage after hepatectomy?

PURPOSE

To evaluate the effect of morphine or morphine equivalents on the risk of bile leakage (BL) after hepatectomy.

METHODS

The subjects of this retrospective study were 379 patients who underwent hepatectomy without biliary reconstruction and biliary decompression tube insertion at Gunma University between 2016 and 2020. Clinical BL was defined as International Study Group of Liver Surgery post-hepatectomy bile leakage Grade B or C.

RESULTS

Intra- and post-operative analgesia comprised intravenous patient-controlled analgesia (IV-PCA) with fentanyl (n = 58), epidural analgesia with fentanyl (n = 157), epidural analgesia with morphine (n = 151), and epidural analgesia with ropivacaine or levobupivacaine (n = 13). Clinical BL was diagnosed in 14 of the 379 (3.7%) patients. The significant risk factors for clinical BL were hepatocellular carcinoma (HCC), elevated serum total bilirubin, high indocyanine green retention at 15 min, elevated Mac-2-binding protein glycosylated isomer, prolonged duration of surgery, and a large volume of blood loss. There was no significant correlation of clinical BL with intra- and post-operative analgesia and total oral morphine equivalents.

CONCLUSION

Intra- and post-operative IV-PCA and epidural analgesia were not related to clinical BL after hepatectomy. Based on our data, fentanyl and morphine can be administered safely as epidural or intravenous analgesic agents.

Opioid Use Increases the Risk of Delirium in Critically Ill Adults Independently of Pain

Rationale: It is unclear whether opioid use increases the risk of ICU delirium. Prior studies have not accounted for confounding, including daily severity of illness, pain, and competing events that may preclude delirium detection.Objectives: To evaluate the association between ICU opioid exposure, opioid dose, and delirium occurrence.Methods: In consecutive adults admitted for more than 24 hours to the ICU, daily mental status was classified as awake without delirium, delirium, or unarousable. A first-order Markov model with multinomial logistic regression analysis considered four possible next-day outcomes (i.e., awake without delirium, delirium, unarousable, and ICU discharge or death) and 11 delirium-related covariables (baseline: admission type, age, sex, Acute Physiology and Chronic Health Evaluation IV score, and Charlson comorbidity score; daily: ICU day, modified Sequential Organ Failure Assessment, ventilation use, benzodiazepine use, and severe pain). This model was used to quantify the association between opioid use, opioid dose, and delirium occurrence the next day.Measurements and Main Results: The 4,075 adults had 26,250 ICU days; an opioid was administered on 57.0% (n = 14,975), severe pain occurred on 7.0% (n = 1,829), and delirium occurred on 23.5% (n = 6,176). Severe pain was inversely associated with a transition to delirium (odds ratio [OR] 0.72; 95% confidence interval [CI], 0.53-0.97). Any opioid administration in awake patients without delirium was associated with an increased risk for delirium the next day [OR, 1.45; 95% CI, 1.24-1.69]. Each daily 10-mg intravenous morphine-equivalent dose was associated with a 2.4% increased risk for delirium the next day.Conclusions: The receipt of an opioid in the ICU increases the odds of transitioning to delirium in a dose-dependent fashion.

A Randomized Controlled Trial Evaluating the Analgesic Effect of the Combination of Methadone With Morphine for Cancer Related Pain

CONTEXT AND OBJECTIVES

Although opioids play an indispensable role in the management of cancer-related pain, inadequate pain relief still occurs. The primary objective of this study was to evaluate whether the combination of a low dose of methadone with morphine promotes a reduction in opioid consumption; the secondary objectives were if the association promotes lower pain intensity, and adverse effects (AEs).

MATERIALS AND METHODS

A sample if 41 patients with cancer-related pain in palliative setting were included. Patients were starting the third step of the analgesic ladder, and 1 group (n=21) achieve methadone (2.5 mg/12 h) in combination with morphine/methadone, and another group (n=20) received morphine alone. Both groups could use morphine (5 mg) as needed to maintain pain intensity <4, and adjuvant in stable dose. The following outcomes were evaluated: total morphine dose, pain intensity, and AEs.

RESULTS

There was no difference in the number of adjuvants, and the dose of morphine used. Pain intensity was significantly lower in the morphine/methadone group after 2 weeks, with no statistically significant difference at other timepoints. There was no difference between groups in the AEs.

CONCLUSION

Low dose of methadone in combination with morphine provided faster pain control as compared with morphine alone, and although this study was not powered to show differences in AEs, we did not notice a difference.

Inches, Centimeters, and Yards: Overlooked Definition Choices Inhibit Interpretation of Morphine Equivalence

OBJECTIVE

Morphine-standardized doses are used in clinical practice and research to account for molecular potency. Ninety milligrams of morphine equivalents (MME) per day are considered a "high dose" risk threshold in guidelines, laws, and by payers. Although ubiquitously cited, the "CDC definition" of daily MME lacks a clearly defined denominator. Our objective was to assess denominator-dependency on "high dose" classification across competing definitions.

METHODS

To identify definitional variants, we reviewed literature and electronic prescribing tools, yielding 4 unique definitions. Using Prescription Drug Monitoring Programs data (July to September 2018), we conducted a population-based cohort study of 3,916,461 patients receiving outpatient opioid analgesics in California (CA) and Florida (FL). The binary outcome was whether patients were deemed "high dose" (>90 MME/d) compared across 4 definitions. We calculated I2 for heterogeneity attributable to the definition.

RESULTS

Among 9,436,640 prescriptions, 42% overlapped, which led denominator definitions to impact daily MME values. Across definitions, average daily MME varied 3-fold (range: 17 to 52 [CA] and 23 to 65 mg [FL]). Across definitions, prevalence of "high dose" individuals ranged 5.9% to 14.2% (FL) and 3.5% to 10.3% (CA). Definitional variation alone would impact a hypothetical surveillance study trying to establish how much more "high dose" prescribing was present in FL than CA: from 39% to 84% more. Meta-analyses revealed strong heterogeneity (I2 range: 86% to 99%). In sensitivity analysis, including unit interval 90.0 to 90.9 increased "high dose" population fraction by 15%.

DISCUSSION

While 90 MME may have cautionary mnemonic benefits, without harmonization of calculation, its utility is limited. Comparison between studies using daily MME requires explicit attention to definitional variation.

Comparison of Oral Loading Dose to Intravenous Acetaminophen in Children for Analgesia After Tonsillectomy and Adenoidectomy: A Randomized Clinical Trial

BACKGROUND

Acetaminophen is a frequently used adjunct analgesic in pediatric patients undergoing tonsillectomy and adenoidectomy. We compared opioid administration following preoperative intravenous (IV) or oral acetaminophen in addition to a standard multimodal regimen to test the hypothesis that 1 loading dose approach would provide superior opioid sparing effects among pediatric surgical patients undergoing tonsillectomy and adenoidectomy.

METHODS

This single-center, double-blind, double-dummy prospective randomized study was conducted in patients ages 3 to 15 years undergoing tonsillectomy and adenoidectomy with or without myringotomy and tube placement between September 2017 and July 2019. Subjects received 1 dose of either oral acetaminophen 30 mg/kg with IV placebo (oral group) or IV acetaminophen 15 mg/kg with oral placebo (IV group). Acetaminophen plasma levels were measured at 2 timepoints to evaluate safety and determine plasma levels attained by each dosing regimen. Intraoperative opioid administration and postoperative analgesia were standardized. Standardized postoperative multimodal analgesia included opioid if needed to control pain assessed by standardized validated pediatric pain scales. The primary outcome measure was total opioid administration in the first 24 hours after surgery. Continuous data were not normally distributed and were analyzed using the Wilcoxon rank sum test and the Hodges-Lehman estimator of the median difference. Clinical significance was defined as a 100 µg/kg IV morphine equivalents per day difference.

RESULTS

Sixty-six subjects were randomized into and completed the study (29 women, 37 men; age 5.9 ± 3.0 years; percentile weight for age 49.5 ± 30.2; no differences between groups). There was no opioid dose difference between oral (median 147.6; interquartile range [IQR], 119.6-193.0 µg/kg) and IV groups (median 125.4; IQR, 102.8-150.9 µg/kg; median difference 21.3; 95% confidence interval [CI] -2.5 to 44.2 µg/kg IV morphine equivalents; P = .13). No acetaminophen levels exceeded the predefined safety threshold (40 mg/L). No difference was found in the percentage of patients with severe pain: 50.0% oral group, 47.2% IV group; relative risk of severe pain in IV 0.94; 95% CI, 0.57-1.6; P = .82. Postoperative plasma acetaminophen levels were higher in oral (22; IQR, 16-28 mg/L) than IV (20; IQR, 17-22 mg/L) group (median difference 7.0; 4.0-8.0 mg/L; P = .0001).

CONCLUSIONS

Opioid-sparing effects did not differ following an oral or standard IV acetaminophen loading dose with no identified acetaminophen toxicity in pediatric patients undergoing tonsillectomy and adenoidectomy who received standardized multimodal postoperative analgesia. An oral loading dose may provide more consistent serum acetaminophen levels at lower cost compared to a standard IV dose.

The American Society of Pain and Neuroscience (ASPN) Best Practices and Guidelines for the Interventional Management of Cancer-Associated Pain

Moderate to severe pain occurs in many cancer patients during their clinical course and may stem from the primary pathology, metastasis, or as treatment side effects. Uncontrolled pain using conservative medical therapy can often lead to patient distress, loss of productivity, shorter life expectancy, longer hospital stays, and increase in healthcare utilization. Various publications shed light on strategies for conservative medical management for cancer pain and a few international publications have reviewed limited interventional data. Our multi-institutional working group was assembled to review and highlight the body of evidence that exists for opioid utilization for cancer pain, adjunct medication such as ketamine and methadone and interventional therapies. We discuss neurolysis via injections, neuromodulation including targeted drug delivery and spinal cord stimulation, vertebral tumor ablation and augmentation, radiotherapy and surgical techniques. In the United States, there is a significant variance in the interventional treatment of cancer pain based on fellowship training. As a first of its kind, this best practices and interventional guideline will offer evidenced-based recommendations for reducing pain and suffering associated with malignancy.

Opioid dependence disorder and comorbid chronic pain: comparison of groups based on patient-attributed direction of the causal relationship between the two conditions

Background:

Chronic pain is highly prevalent in treatment-seeking opioid-dependent patients; therefore, this comorbid presentation is an important clinical consideration for both addiction and pain specialists. The objectives of the present study were to examine whether the direction of causal attribution of opioid dependence disorder and chronic pain resulted in two distinct clinical populations, and, if so, to compare treatment received during the 5-year follow-up period.

Methods:

Participants comprised opioid-dependent patients with chronic pain who reported a perceived causal relationship, in either direction, between the development of these two conditions (n = 252). A range of health- and addiction-related instruments were used at study inception. Treatment characteristics were obtained for the follow-up period from national health registers.

Results:

Those reporting that pain caused opioid dependence disorder (n = 174; 69%) were characterised by poorer pain-related health, more illicit cannabinoid use (p = 0.031), more frequent illicit use of opioid analgesics (p = 0.025) and they were in receipt of higher doses of prescribed opioid analgesics. Those reporting that opioid dependence disorder caused pain (n = 78; 31%) were characterised by poorer overall physical health (p = 0.002), more severe psychiatric symptoms and more overall drug use (p = 0.001).

Conclusion:

Two distinct clinical populations were identified, determined by how participants perceive the causal relationship between opioid dependence disorder and chronic pain. These two populations have differing clinical profiles and treatment requirements: those reporting that pain caused opioid dependence disorder were characterised by poorer pain-related health and more illicit use of drugs with analgesic properties; and those reporting that opioid dependence disorder caused pain were characterised by more overall use of substances, multiple substance use and more intravenous substance use and poorer general health. Identifying the causal direction, where such a relationship exists, could help addiction and pain services to develop more effective, individualised treatment strategies.

Effect of methadone on QTc in infants

OBJECTIVE

Methadone has been associated with prolongation of the QTc interval (QTc) on electrocardiogram (ECG). In infants, the effects of methadone on the QTc are not well described. Our study's objective is to evaluate the QTc in infants being treated with methadone.

METHODS

We conducted a retrospective study in infants receiving methadone. We collected demographic data, methadone dose, and QTc. A blinded-to-disease-state pediatric electrophysiologist determined the QTc. Baseline ECG was defined as an ECG obtained while not on methadone therapy, and QTc on baseline ECG was compared with treatment QTc. A significant change was defined as any absolute QTc greater than 500 or a QTc greater than 460 with an increase from baseline of greater than 40 ms.

RESULTS

A total of 44 infants comprised the study population. The mean gestational age was 32.3 ± 5.51 weeks. The median age of initiation was 66 days. The median dose was 0.52 mg/kg/day in oral methadone equivalents. Nine patients were on high dose methadone (>1 mg/kg/day in oral methadone equivalents). The mean baseline QTc was 421 ± 27 and the mean change on methadone was -2 ms. No patient had a QTc greater than 500 on methadone. One patient had a QTc of 467 and 46 ms change from baseline, with no clinically significant impact.

CONCLUSION

In our study population, methadone did not significantly prolong the QTc. Further prospective study is warranted to determine the utility and frequency of ECGs in infants receiving methadone.

Computer-Assisted Instrument Guidance to Improve Adductor Canal Block Performance for Total Knee Arthroplasty: A Pilot Randomized Controlled Trial

Background Postoperative pain associated with total knee arthroplasties (TKAs) is routinely managed with ultrasound-guided adductor canal blocks (ACBs). Computer-assisted instrument guidance (CAIG) systems can supplement the existing ultrasound machinery and block needles. CAIG systems allow the operator to navigate the needle in real time while displaying a projected trajectory of its path onto the ultrasound monitor. This study explored how ACBs performed with CAIG compare with conventional ultrasound-only ACBs in terms of block efficiency, success, and potential tissue damage for patients undergoing TKA. Methodology A total of 26 patients undergoing TKA under spinal anesthesia with an ACB were randomized to ACB utilizing conventional real-time ultrasound or to ACB utilizing real-time ultrasound supplemented with CAIG. The primary outcome measure was time to block completion. The secondary outcome measures included number of needle insertions, postoperative pain scores until postoperative day three, postoperative muscle weakness, opioid requirements on postoperative day zero, length of stay, and patient satisfaction with pain management. Results The time required to complete the block as well as the number of needle insertion attempts were similar between the CAIG and conventional ACB groups. Postoperative outcomes such as pain scores up to postoperative day three, postoperative muscle weakness, opioid requirements on postoperative day zero, length of stay, and patient satisfaction with perioperative pain management were comparable between the CAIG and conventional ACB groups. Conclusions CAIG does not reduce ACB performance times or patient outcomes when performed by experienced anesthesiologists.

The reporting of observational studies of drug effectiveness and safety: recommendations to extend existing guidelines

INTRODUCTION

The use of observational data to assess drug effectiveness and safety can provide relevant information, much of which may not be feasible to obtain through randomized clinical trials. Because observational studies provide critical drug safety and effectiveness information that influences drug policy and prescribing practices, transparent, consistent, and accurate reporting of these studies is critical.

AREAS COVERED

We provide recommendations to extend existing reporting guidelines, covering the main components of primary research studies (methods, results, discussion).

EXPERT OPINION

Our recommendations include extending drug safety and effectiveness guidelines to include explicit checklist items on: study registration, causal diagrams, rationale for measures of effect, comprehensive assessment of bias, comprehensive data cleaning steps, drug equivalents, subject-level drug data visualization, sex and gender-based analyses and results, patient-oriented outcomes, and patient involvement in research.

Bupivacaine local anesthetic to decrease opioid requirements after radical cystectomy: Does formulation matter?

INTRODUCTION

Reduction of opioids is an important goal in the care of patients undergoing radical cystectomy (RC). Liposomal bupivacaine (LB) has been shown to be a safe and effective pain reliever in the immediate postoperative period and has been reported to reduce postoperative opioid requirements. Since the liposomal formulation is predicated on slow systemic absorption, the amount of bupivacaine administered is notably higher than that typically used with standard bupivacaine (SB) formulations. In addition, LB is costly, not universally available, and studies comparing this formulation to SB are lacking. We sought to determine if there is a difference in postoperative opioid requirements in patients who receive LB vs. high dose SB at the time of RC.

METHODS

In May 2019 we transitioned to administration of high-volume SB injected intraoperatively at the time of RC. This prospective cohort was compared to a historical cohort of patients who received injection of LB at the time of surgery. Primary endpoints included postsurgical opioid use measured in morphine equivalent dose (MED) and patient-reported Numeric Rating Scale (NRS) pain scores and length of stay. All patients were managed using principles of enhanced recovery after surgery (ERAS).

RESULTS

From May 2019 through August 2019, 28 patients underwent RC and met eligibility criteria to receive SB at the time of surgery. They were compared to a historical cohort of 34 patients who received LB between November 2017 and July 2018. There was no difference in MED exposure either in the postanesthesia care unit (SB 9.0 ± 8.9 MED vs. LB 6.5 ± 9.4 MED, P= 0.29) or during the remainder of the hospital stay (SB 36.8 ± 56.9 MED vs. LB 42.1 ± 102.5 MED, P= 0.81), no difference in NRS pain scores on postoperative day 1 (SB 2.6 ± 1.6 vs. LB 2.1 ± 1.7, P= 0.23), day 2 (SB 2.4 ± 1.8 vs. LB 1.9 ± 1.6, P= 0.19), or day 3 (SB 1.9 ± 1.8 vs. LB 1.7 ± 1.7, P= 0.69) and no difference in length of stay (SB 5.0 ± 1.7 days, LB 4.9 ± 3.3 days, P= 0.93). Subgroup analysis of open RC and robotic-assisted RC showed no significant difference in MED or pain scores between LB and SB patients.

CONCLUSIONS

Among patients undergoing RC under ERAS protocol there was no significant difference in postoperative opioid consumption, NRS pain scores, or length of stay among patients receiving SB compared to LB.

Management of pain in colorectal cancer patients

In this review we focus on the pathophysiology of CRC-related pain and discuss currently applied pain management. Pain is a symptom reported by over 70 % of colorectal cancer (CRC) patients. It remains a feared and debilitating consequence of both cancer and cancer-related treatment. There are many options for pain management in CRC, consisting of intravenous, oral or topical medications. In order to address the full spectrum of pain, proper treatment should address the nociceptive, neuropathic and/or psychogenic pain component. Currently available methods do not bring pain relief to satisfying number of patients and, if used improperly, can cause a number of complications. Therefore, future treatments should focus primarily on alleviating pain, but also on reducing possible side effects. In this article we cover recent and promising pharmacological and non- pharmacological developments emerging in the field of CRC treatment.

Oncologic Emergencies: Palliative Care in the Emergency Department Setting

BACKGROUND

Palliative care is an essential component of emergency medicine, as many patients with terminal illness will present to the emergency department (ED) for symptomatic management at the end of life (EOL).

OBJECTIVE

This narrative review evaluates palliative care in the ED, with a focus on the literature behind management of EOL symptoms, especially dyspnea and cancer-related pain.

DISCUSSION

As the population ages, increasing numbers of patients present to the ED with severe EOL symptoms. An understanding of the role of palliative care in the ED is crucial to effectively communicating with these patients to determine their goals and provide medical care in line with their wishes. Beneficence, nonmaleficence, and patient autonomy are essential components of palliative care. Patients without medical decision-making capacity may have an advance directive, do not resuscitate or do not intubate order, or Portable Medical Orders for Life-Sustaining Treatment available to assist clinicians. Effective and empathetic communication with patients and families is vital to EOL care discussions. Two of the most common and distressing symptoms at the EOL are dyspnea and pain. The most effective treatment of EOL dyspnea is opioids, with literature showing little efficacy for other therapies. The most effective treatment for cancer-related pain is opioids, with expeditious pain control achievable with a rapid fentanyl titration. It is also important to address nausea, vomiting, and secretions, as these are common at the EOL.

CONCLUSIONS

Emergency clinicians play a vital role in EOL patient care. Clear, empathetic communication and treatment of EOL symptoms are essential.

Methadone and a Clinical Pathway in Adolescent Idiopathic Scoliosis Surgery: A Historically Controlled Study

STUDY DESIGN

Historically controlled clinical trial.

OBJECTIVES

Patients presenting for correction of adolescent idiopathic scoliosis (AIS) by posterior spinal fusion may benefit from structured clinical pathways. We studied the effects of implementing a published clinical pathway for the perioperative care of patients with AIS that required intraoperative use of methadone at our institution.

METHODS

We performed a historically controlled clinical trial of patients undergoing posterior spinal fusion for AIS by comparing a retrospectively collected control group of 25 patients with a prospective experimental group of 14 patients receiving methadone, gabapentin, propofol, and remifentanil as part of a new clinical pathway.

RESULTS

Use of the pathway decreased average pain scores evaluated by the Numeric Rating Scale in the 24 hours following surgery (4.8 [4-6] to 3.4 [2-4], P = .03 [-2.6 to -0.2; t = -2.3]) and postoperative opioid consumption by 76% (41 [29-51] mg to 10 [4-17] mg, P < .001 [-45 to -15; Welch's t = 4.9]) during the same period. Improved analgesia and reduced reliance on opioids facilitated other postoperative elements of the clinical pathway and shortened the average hospital length of stay by 1 day (4 [3-6] days to 3 [3-5] days, P = .001 [-2 to -1; U = 67, Z = -3.3]).

CONCLUSIONS

Multimodal analgesia and a clinical pathway add value in the perioperative care of patients undergoing posterior spinal fusion for AIS by improving analgesia and shortening hospitalization. The prospective arm of the trial was registered at clinicaltrials.gov under NCT02481570.

Sedation, Analgesia, and Paralysis in COVID-19 Patients in the Setting of Drug Shortages

The rapid spread of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has led to a global pandemic. The 2019 coronavirus disease (COVID-19) presents with a spectrum of symptoms ranging from mild to critical illness requiring intensive care unit (ICU) admission. Acute respiratory distress syndrome is a major complication in patients with severe COVID-19 disease. Currently, there are no recognized pharmacological therapies for COVID-19. However, a large number of COVID-19 patients require respiratory support, with a high percentage requiring invasive ventilation. The rapid spread of the infection has led to a surge in the rate of hospitalizations and ICU admissions, which created a challenge to public health, research, and medical communities. The high demand for several therapies, including sedatives, analgesics, and paralytics, that are often utilized in the care of COVID-19 patients requiring mechanical ventilation, has created pressure on the supply chain resulting in shortages in these critical medications. This has led clinicians to develop conservation strategies and explore alternative therapies for sedation, analgesia, and paralysis in COVID-19 patients. Several of these alternative approaches have demonstrated acceptable levels of sedation, analgesia, and paralysis in different settings but they are not commonly used in the ICU. Additionally, they have unique pharmaceutical properties, limitations, and adverse effects. This narrative review summarizes the literature on alternative drug therapies for the management of sedation, analgesia, and paralysis in COVID-19 patients. Also, this document serves as a resource for clinicians in current and future respiratory illness pandemics in the setting of drug shortages.

Clinical Factors Associated With Practice Variation in Discharge Opioid Prescriptions After Pancreatectomy

OBJECTIVE

To characterize opioid discharge prescriptions for pancreatectomy patients.

BACKGROUND

Wide variation in and over-prescription of opioids after surgery contribute to the United States opioid epidemic through persistent use past the postoperative period. Objective strategies guiding discharge opioid prescriptions for oncologic surgery are lacking, and factors driving prescription amount are not fully delineated.

METHODS

Characteristics of pancreatectomy patients (March 2016-August 2017) were retrospectively abstracted from a prospective database. Discharge opioids prescriptions were converted to oral morphine equivalents (OME). Regression models identified variables associated with discharge OME.

RESULTS

In 158 consecutive patients, median discharge OME was 250 mg (range 0-3950). Discharge OME was labeled "low" (<200 mg) for 33 patients (21%) and "high" (>400 mg) for 38 (24%). Only shorter operative time (odds ratio [OR]-0.14, P = 0.004) and inpatient team (OR-15.39, P < 0.001) were independently associated with low discharge OME. Older age was the only variable associated with high discharge OME. Fifty-seven patients (36%) used zero opioids in the last 24-hours predischarge, yet 52 of 57 (91%) still received discharge opioids. Older age (OR-1.07), grade B/C pancreatic fistula (OR-3.84), and epidural use (OR-3.12) were independently associated with zero last-24-hours OME (all P ≤ 0.040).

CONCLUSIONS

The wide variation in discharge opioid prescriptions is heavily influenced by provider routine/bias and not by objective criteria such as last-24-hours OME. Quality improvement strategies could include aggressive weaning protocols to increase the proportion of patients with zero/near-zero last-24-hour OME and limiting prescriptions to a conservative multiplier of the last-24-hour OME.

Association between intraoperative and postoperative epidural or intravenous patient-controlled analgesia and pancreatic fistula after distal pancreatectomy

PURPOSE

This study aimed to elucidate the association between postoperative pancreatic fistula (POPF) after distal pancreatectomy (DP) and clinicopathological factors and intraoperative and postoperative epidural or intravenous patient-controlled analgesia (IV-PCA).

METHODS

We reviewed data of 116 patients who underwent distal pancreatectomy at Gunma University Hospital from October 2000 to October 2019. Clinical POPF was defined as the International Study Group of Pancreatic Fistula grade B or C.

RESULTS

Intraoperative and postoperative analgesia included fentanyl-mediated IV-PCA (n = 37, 32%), fentanyl-mediated epidural analgesia (n = 39, 34%), and morphine-mediated epidural analgesia (n = 40, 34%). All patients had received analgesia. Clinical POPF occurred in 34 of the 116 (29%) DP cases. Male sex (P = 0.035) and the length of operation time (P = 0.0070) were significant risk factors of clinical POPF. Furthermore, a thick pancreas was more likely to cause clinical POPF than a thin one (P = 0.052). No statistically significant difference was found between other factors, including intraoperative and postoperative analgesia (P = 0.95), total median oral morphine equivalents (P = 0.23), and clinical POPF.

CONCLUSION

Intraoperative and postoperative epidural analgesia and IV-PCA are not associated with clinical POPF after DP. Our results suggest that morphine and fentanyl can be used as IV-PCA or epidural analgesia.

Opioid rotation from transdermal fentanyl to continuous subcutaneous hydromorphone in a cachectic patient: A case report and review of the literature

Opioid rotation from transdermal fentanyl to an alternate opioid is often necessitated in advanced disease, but is fraught with uncertainty due to variable absorption from the patch in end-stage illness and the lack of a clearly established opioid rotation ratio. The manufacturer of transdermal fentanyl provides opioid rotation recommendations only for rotation from the oral morphine equivalent daily dose (MEDD) of opioid to the patch, not in the opposite direction. This is a case report of a single patient with cancer and cachexia admitted to the palliative care unit of a large academic medical centre in Canada. The patient is a 50-year-old female with widely metastatic breast cancer who developed opioid toxicity when maintenance transdermal fentanyl patch therapy (100 μg patch applied every 72 h) was rotated to subcutaneous hydromorphone infusion to improve pain control. Hydromorphone was initiated at a rate of 1 mg/h by continuous infusion based on an opioid rotation ratio for transdermal fentanyl (μg/h):MEDD (mg/day) of 1:2.4. Opioid toxicity eventually resolved with downward titration of hydromorphone to only 30% of the initially estimated equianalgesic dose. This case highlights the need for close follow-up of all patients undergoing opioid rotation from transdermal fentanyl and reinforces the need to reduce the initial dose of the new opioid by 30%-50% of the calculated MEDD, especially when rotating from a high dose of transdermal fentanyl, or if there are factors potentially impairing absorption from the patch such as age, cachexia and weight loss, or if rotation is performed for reasons other than uncontrolled pain.

Development and Performance of a Web-Based Tool to Adjust Urine Toxicology Testing Frequency: Retrospective Study

BACKGROUND

Several pain management guidelines recommend regular urine drug testing (UDT) in patients who are being treated with chronic opioid analgesic therapy (COAT) to monitor compliance and improve safety. Guidelines also recommend more frequent testing in patients who are at high risk of adverse events related to COAT; however, there is no consensus on how to identify high-risk patients or on the testing frequency that should be used. Using previously described clinical risk factors for UDT results that are inconsistent with the prescribed COAT, we developed a web-based tool to adjust drug testing frequency in patients treated with COAT.

OBJECTIVE

The objective of this study was to evaluate a risk stratification tool, the UDT Randomizer, to adjust UDT frequency in patients treated with COAT.

METHODS

Patients were stratified using an algorithm based on readily available clinical risk factors into categories of presumed low, moderate, high, and high+ risk of presenting with UDT results inconsistent with the prescribed COAT. The algorithm was integrated in a website to facilitate adoption across practice sites. To test the performance of this algorithm, we performed a retrospective analysis of patients treated with COAT between June 2016 and June 2017. The primary outcome was compliance with the prescribed COAT as defined by UDT results consistent with the prescribed COAT.

RESULTS

979 drug tests (867 UDT, 88.6%; 112 oral fluid testing, 11.4%) were performed in 320 patients. An inconsistent drug test result was registered in 76/979 tests (7.8%). The incidences of inconsistent test results across the risk tool categories were 7/160 (4.4%) in the low risk category, 32/349 (9.2%) in the moderate risk category, 28/338 (8.3%) in the high risk category, and 9/132 (6.8%) in the high+ risk category. Generalized estimating equation analysis demonstrated that the moderate risk (odds ratio (OR) 2.1, 95% CI 0.9-5.0; P=.10), high risk (OR 2.0, 95% CI 0.8-5.0; P=.14), and high risk+ (OR 2.0, 95% CI 0.7-5.6; P=.20) categories were associated with a nonsignificantly increased risk of inconsistency vs the low risk category.

CONCLUSIONS

The developed tool stratified patients during individual visits into risk categories of presenting with drug testing results inconsistent with the prescribed COAT; the higher risk categories showed nonsignificantly higher risk compared to the low risk category. Further development of the tool with additional risk factors in a larger cohort may further clarify and enhance its performance.

Dynamic assessment of the pupillary reflex in patients on high-dose opioids

Background and aims Pupil size and reaction are influenced by opioids, an effect that is not considered to be affected by opioid tolerance. As clinicians have observed patients on high-dose opioids who exhibited seemingly normal pupil sizes, we wanted to dynamically assess the pupillary reflex in cancer patients on high-dose opioids. Methods We performed a dynamic assessment of the pupillary reflex in cancer patients on high-dose opioids and a control group of healthy volunteers using a portable, monocular, infrared pupillometer. We also performed a clinical examination and measured blood concentrations of opioids and their active metabolites. Results Sixty three patients who were on opioids for 2 months (median time) and on an oral morphine equivalent dose of 250 mg (median dose) were investigated. Most patients used more than one opioid. When correcting for age, pupil size in the group that had received no increase of opioid dose over the last 14 days was not significantly different from pupil size in the healthy volunteer group (p = 0.76), while the group that had increased the dose of opioids differed significantly from healthy volunteers (p = 0.006). We found no statistically significant correlation between total oral morphine equivalents and pupillary reactions or between blood opioid or opioid metabolite concentrations and baseline pupillary changes. Conclusion Pupillary changes do take place in patients on opioids. However, tolerance to these changes occurs when medication is not increased over time. Dynamic pupillometry can give additional information about the degree of tolerance to opioids. Implications These findings elucidate previous misconceptions regarding pupillary effects and tolerance to opioids.

Implementation of a Reduced Opioid Utilization Protocol for Radical Cystectomy

BACKGROUND: Radical cystectomy (RC) often requires a prolonged course of opioid medications for postoperative pain management. We implemented a Reduced Opioid Utilization (ROU) protocol to decrease exposure to opioid medications. OBJECTIVE: To determine the impact of the ROU protocol on opioid exposure, pain control, inpatient recovery, and complication rates among patients who underwent RC. METHODS: The ROU protocol includes standardized recovery pathways, a multimodal opioid-sparing pain regimen, and improved patient and provider education regarding non-opioid medications. Opioid exposure was calculated as morphine equivalent dose (MED), and was compared between RC patients following the ROU protocol and patients who previously followed our traditional pathway. Opioid-related adverse drug events (ORADEs), pain scores, length of stay, and 90-day complications, readmission, and mortality were also compared between cohorts. RESULTS: 104 patients underwent RC, 54 (52%) of whom followed the ROU protocol. ROU patients experienced a statistically significant decrease in opioid exposure in the post-anesthesia care unit (p = 0.003) and during their postoperative recovery (85.7±21.0 MED vs 352.6±34.4 MED, p < 0.001). The ROU protocol was associated with a statistically significant decrease in ORADEs after surgery. There was no significant difference in average pain scores, length of stay, readmissions, or 90-day complication or mortality rates. CONCLUSIONS: The ROU protocol decreased opioid use by 77% without compromising pain control or increasing the rate of complications. This study demonstrates the efficacy of non-opioid medications in controlling postoperative pain, and highlights the role providers can play to decrease patient exposure to opioids after RC surgery.

Opioid Management in Older Adults with Chronic Kidney Disease: A Review

Chronic pain, a common comorbidity of chronic kidney disease, is consistently under-recognized and difficult to treat in older adults with nondialysis chronic kidney disease. Given the decreased kidney function associated with aging and chronic kidney disease, these patients are at increased risk for drug accumulation and adverse events. Emerging research has demonstrated the efficacy of opioids in chronic kidney disease patients, but research specifically focusing on older, nondialysis chronic kidney disease patients is scarce. The primary objective of this review is to determine which oral and transdermal opioids are the safest for older, nondialysis chronic kidney disease patients. We discuss the limited existing evidence on opioid prescription in older, nondialysis chronic kidney disease patients and provide recommendations for the management of oral and transdermal opioids in this patient population. Specifically, transdermal buprenorphine, transdermal fentanyl, and oral hydromorphone are the most tolerable opioids in these patients; hydrocodone, oxycodone, and methadone are useful but require careful monitoring; and tramadol, codeine, morphine, and meperidine should be avoided due to risk of accumulation and adverse events. Because older adults with nondialysis chronic kidney disease are at increased risk for adverse events, vigilant monitoring of opioid prescription is critical. Lastly, collaboration among an interprofessional clinical team can ensure safe prescription of opioids in older adults with nondialysis chronic kidney disease.

Opioid use and length of stay following minimally invasive pectus excavatum repair in 436 patients - Benefits of an enhanced recovery pathway

PURPOSE

The purpose of this study was to determine outcomes of an enhanced recovery pathway (ERP) for minimally invasive repair of pectus excavatum (MIRPE) at a high volume center, hypothesizing it is associated with decreased opioid requirement and shorter hospital stay.

METHODS

Patients were categorized into pre-ERP (1998-2006), transition (2007-2011), and ERP (2012-2017) cohorts. Data were abstracted from medical records. Univariate and multivariable analyses compared opioid utilization, length of stay (LOS), and complications between cohorts. Opioids were converted to morphine daily dose per kilogram (MEDD/kg).

RESULTS

Of 436 patients, 186 were ERP, 104 were transition, and 146 were pre-ERP. ERP was associated with decreased hospital opioid utilization (mean MEDD/kg 0.5 ± 0.2 vs 0.7 ± 0.4 vs 0.7 ± 0.8 p < .001) and shorter median LOS (3 vs 4 vs 5 days, p < .001) despite equivalent pain scores at discharge (2.7 ± 0.1 vs 2.8 ± 0.2 vs 2.9 ± 0.3, p = .73). Most ERP patients (76%) had LOS ≤3 days. Differences in LOS between ERP, transition, and pre-ERP persisted on multivariable analysis after adjusting for confounding factors. Post-operative complications were rare and not different between groups (p > .05).

CONCLUSIONS

Implementation of our ERP was associated with decreased opioid requirement and shorter hospital stay. ERPs are a valuable tool in pediatric surgery given the current emphasis on optimizing opioid and resource utilization.

LEVELS OF EVIDENCE

Level III (Retrospective comparative study).

Pain and Its Long-term Interference of Daily Life After Critical Illness

BACKGROUND

Persistent pain likely interferes with quality of life in survivors of critical illness, but data are limited on its prevalence and risk factors. We sought to determine the prevalence of persistent pain after critical illness and its interference with daily life. Additionally, we sought to determine if intensive care unit (ICU) opioid exposure is a risk factor for its development.

METHODS

In a cohort of adult medical and surgical ICU survivors, we used the brief pain inventory (BPI) to assess pain intensity and pain interference of daily life at 3 and 12 months after hospital discharge. We used proportional odds logistic regression with Bonferroni correction to evaluate the independent association of ICU opioid exposure with BPI scores, adjusting for potential confounders including age, preadmission opioid use, frailty, surgery, severity of illness, and durations of delirium and sepsis while in the ICU.

RESULTS

We obtained BPI outcomes in 295 patients overall. At 3 and 12 months, 77% and 74% of patients reported persistent pain symptoms, respectively. The median (interquartile range) pain intensity score was 3 (1, 5) at both 3 and 12 months. Pain interference with daily life was reported in 59% and 62% of patients at 3 and 12 months, respectively. The median overall pain interference score was 2 (0, 5) at both 3 and 12 months. ICU opioid exposure was not associated with increased pain intensity at 3 months (odds ratio [OR; 95% confidence interval], 2.12 [0.92-4.93]; P = .18) or 12 months (OR, 2.58 [1.26-5.29]; P = .04). ICU opioid exposure was not associated with increased pain interference of daily life at 3 months (OR, 1.48 [0.65-3.38]; P = .64) or 12 months (OR, 1.46 [0.72-2.96]; P = .58).

CONCLUSIONS

Persistent pain is prevalent after critical illness and frequently interferes with daily life. Increased ICU opioid exposure was not associated with worse pain symptoms. Further studies are needed to identify modifiable risk factors for persistent pain in the critically ill and the effects of ICU opioids on patients with and without chronic pain.

Inpatient Opioid Use After Pancreatectomy: Opportunities for Reducing Initial Opioid Exposure in Cancer Surgery Patients

BACKGROUND

Despite advances in enhanced surgical recovery programs, strategies limiting postoperative inpatient opioid exposure have not been optimized for pancreatic surgery. The primary aims of this study were to analyze the magnitude and variations in post-pancreatectomy opioid administration and to characterize predictors of low and high inpatient use.

METHODS

Clinical characteristics and inpatient oral morphine equivalents (OMEs) were downloaded from electronic records for consecutive pancreatectomy patients at a high-volume institution between March 2016 and August 2017. Regression analyses identified predictors of total OMEs as well as highest and lowest quartiles.

RESULTS

Pancreatectomy was performed for 158 patients (73% pancreaticoduodenectomy). Transversus abdominus plane (TAP) block was performed for 80% (n = 127) of these patients, almost always paired with intravenous patient-controlled analgesia (IV-PCA), whereas 15% received epidural alone. All the patients received scheduled non-opioid analgesics (median, 2). The median total OME administered was 423 mg (range 0-4362 mg). Higher total OME was associated with preoperative opioid prescriptions (p < 0.001), longer hospital length of stay (LOS; p < 0.001), and no epidural (p = 0.006). The lowest and best quartile cutoff was 180 mg of OME or less, whereas the highest and worst quartile cutoff began at 892.5 mg. After adjustment for inpatient team, only epidural use [odds ratio (OR) 0.3; p = 0.04] predicted lowest-quartile OME. Preoperative opioid prescriptions (OR 8.1; p < 0.001), longer operative time (OR 3.4; p = 0.05), and longer LOS (OR 1.1; p = 0.007) predicted highest-quartile OME.

CONCLUSIONS

Preoperative opioid prescriptions and longer LOS were associated with increased inpatient OME, whereas epidural use reduced inpatient OME. Understanding the predictors of inpatient opioid use and the variables predicting the lowest and highest quartiles can inform decision-making regarding preoperative counseling, regional anesthetic block choice, and novel inpatient opioid weaning strategies to reduce initial postoperative opioid exposure.

Opioid Use and Potency Are Associated With Clinical Features, Quality of Life, and Use of Resources in Patients With Gastroparesis

BACKGROUND & AIMS

Many patients with gastroparesis are prescribed opioids for pain control, but indications for opioid prescriptions and the relationship of opioid use to gastroparesis manifestations are undefined. We characterized associations of use of potent vs weaker opioids and presentations of diabetic and idiopathic gastroparesis.

METHODS

We collected data on symptoms, gastric emptying, quality of life, and health care resource use from 583 patients with gastroparesis (>10% 4-h scintigraphic retention) from the National Institute of Diabetes and Digestive and Kidney Diseases Gastroparesis Consortium, from January 2007 through November 2016. Patients completed medical questionnaires that included questions about opioid use. The opioid(s) were categorized for potency relative to oral morphine. Symptom severities were quantified by Patient Assessment of Upper Gastrointestinal Disorders Symptoms questionnaires. Subgroup analyses compared patients on potent vs weaker opioids and opioid effects in diabetic vs idiopathic etiologies.

RESULTS

Forty-one percent of patients were taking opioids; 82% of these took potent agents (morphine, hydrocodone, oxycodone, methadone, hydromorphone, buprenorphine, or fentanyl). Abdominal pain was the reason for prescription for 61% of patients taking opioids. Mean scores for gastroparesis, nausea/vomiting, bloating/distention, abdominal pain, and constipation scores were higher in opioid users (P ≤ .05). Opioid use was associated with greater levels of gastric retention, worse quality of life, increased hospitalization, and increased use of antiemetic and pain modulator medications compared with nonusers (P ≤ .03). Use of potent opioids was associated with worse gastroparesis, nausea/vomiting, upper abdominal pain, and quality-of-life scores, and more hospitalizations compared with weaker opioids (tapentadol, tramadol, codeine, or propoxyphene) (P ≤ .05). Opioid use was associated with larger increases in gastric retention in patients with idiopathic vs diabetic gastroparesis (P = .008).

CONCLUSIONS

Opioid use is prevalent among patients with diabetic or idiopathic gastroparesis, and is associated with worse symptoms, delays in gastric emptying, and lower quality of life, as well as greater use of resources. Potent opioids are associated with larger effects than weaker agents. These findings form a basis for studies to characterize adverse outcomes of opioid use in patients with gastroparesis and to help identify those who might benefit from interventions to prevent opioid overuse.

Opioids in the treatment of non-specific acute and chronic pain

After reading this article, the reader will be familiar with the general classes of opioid agonists and partial agonists, the basics of the pharmacokinetics and pharmacodynamics of opioids, the risks of opioid therapy and the requirements for the safe and effective use of opioids in acute and chronic pain. The use of opioids during surgical procedures or anesthesia is not discussed. Also, there is no discussion about various available opioid antagonists that are used to treat overdose and the various disorders associated with their use (including naloxone and naltrexone). Opioids are available, the most powerful and effective analgesics, and have become acceptable drugs for the treatment of acute and cancerous pain. However, there is concern about their use in case of chronic pain, if there is no cancer, because they are long-range ineffective but best suited for stopping this pain. Opioid prescription must be monitored for better use. Chronic pain creates discomfort for these patients, reducing their productivity and efficiency, which, in turn, can lead to economic problems in the country. The choice of Nalbuphine is due to the following reasons: the opioid, which is comparable to morphine by its analgesic potential, but has a better safety profile for nausea, vomiting and respiratory depression; not subject to strict quantitative accounting (extract on prescription form 1); the choice of opioid analgesics is significantly limited in Ukraine.

Intravenous Oxycodone Versus Other Intravenous Strong Opioids for Acute Postoperative Pain Control: A Systematic Review of Randomized Controlled Trials

Introduction

Optimal pain management is crucial to the postoperative recovery process. We aimed to evaluate the efficacy and safety of intravenous oxycodone with intravenous fentanyl, morphine, sufentanil, pethidine, and hydromorphone for acute postoperative pain.

Methods

A systematic literature search of PubMed, Cochrane Library, and EMBASE databases was performed for randomized controlled trials published from 2008 through 2017 (inclusive) that evaluated the acute postoperative analgesic efficacy of intravenous oxycodone against fentanyl, morphine, sufentanil, pethidine, and hydromorphone in adult patients (age ≥ 18 years). Outcomes examined included analgesic consumption, pain intensity levels, side effects, and patient satisfaction.

Results

Eleven studies were included in the review; six compared oxycodone with fentanyl, two compared oxycodone with morphine, and three compared oxycodone with sufentanil. There were no eligible studies comparing oxycodone with pethidine or hydromorphone. Overall, analgesic consumption was lower with oxycodone than with fentanyl or sufentanil. Oxycodone exhibited better analgesic efficacy than fentanyl and sufentanil, and comparable analgesic efficacy to morphine. In terms of safety, there was a tendency towards more side effects with oxycodone than with fentanyl, but the incidence of side effects with oxycodone was comparable to morphine and sufentanil. Where patient satisfaction was evaluated, higher satisfaction levels were observed with oxycodone than with sufentanil and comparable satisfaction was noted when comparing oxycodone with fentanyl. Patient satisfaction was not evaluated in the studies comparing oxycodone with morphine.

Conclusions

Our findings suggest that intravenous oxycodone provides better analgesic efficacy than fentanyl and sufentanil, and comparable efficacy to morphine with less adverse events such as sedation. No studies comparing intravenous oxycodone with pethidine or hydromorphone were identified in this review. Better alignment of study methodologies for future research in this area is recommended to provide the best evidence base for a meta-analysis.

Funding

Mundipharma Singapore Holding Pte Ltd, Singapore.

Electronic supplementary material

The online version of this article (10.1007/s40122-019-0122-4) contains supplementary material, which is available to authorized users.

Intravenous acetaminophen vs saline in perioperative analgesia with laparoscopic hysterectomy

BACKGROUND

Opioids are effective for the treatment of postoperative pain but can cause nausea and are associated with dependency with long-term use. Nonopioid medications such as acetaminophen offer the promise of decreasing these nondesirable effects while still providing patient comfort.

OBJECTIVE

The purpose of this study was to compare intravenous acetaminophen with placebo and to evaluate postoperative pain control and opioid usage after laparoscopic hysterectomy.

STUDY DESIGN

We conducted a prospective double-blind randomized study with 183 patients who were assigned randomly (1:1) to receive acetaminophen or placebo (Canadian Task Force Design Classification I). Patients received either 1000 mg of acetaminophen (n=91) or a placebo of saline solution (n=92) at the time of induction of anesthesia and a repeat dose 6 hours later. Both groups self-reported pain and nausea levels preoperatively and at 2, 4, 6, 12, and 24 hours after extubation with the use of a visual analog scale with a score of 0 for no pain to 10 for highest level of pain. Patients self-reported pain, nausea, and postoperative oral opiates that were taken after discharge. All opiates were converted to milligram equivalents of oral morphine for standardization.

RESULTS

There were no significant differences in generalized abdominal pain at any time point postoperatively that included 2 hours (placebo 3.6±2.5 vs acetaminophen 4.4±2.5; P=.07) and up to 24 hours (placebo 3.3±2.4 vs acetaminophen 3.6±2.5; P=.28). Similar results were observed for nausea scores. There were no differences in opioid consumption at any time point including intraoperatively (placebo 4.4±3.9 vs acetaminophen 3.3±4.0; P=.06), post anesthesia care unit (placebo 10.5±10.3 vs acetaminophen 9.7±10.3; P=.59), and up to 24 hours after surgery (placebo 1.4±2.0 vs acetaminophen 1.6±2.1; P=.61). There were no differences in demographics or surgical data between groups.

CONCLUSION

There was no difference between acetaminophen and placebo groups in postoperative pain, satisfaction scores, or opioid requirements. Given the relatively high cost ($23.20 per dose in our study), lack of benefit, and available oral alternatives, our results do not support routine use during hysterectomy.

Perioperative intravenous ketamine for acute postoperative pain in adults

BACKGROUND

Inadequate pain management after surgery increases the risk of postoperative complications and may predispose for chronic postsurgical pain. Perioperative ketamine may enhance conventional analgesics in the acute postoperative setting.

OBJECTIVES

To evaluate the efficacy and safety of perioperative intravenous ketamine in adult patients when used for the treatment or prevention of acute pain following general anaesthesia.

SEARCH METHODS

We searched CENTRAL, MEDLINE and Embase to July 2018 and three trials registers (metaRegister of controlled trials, ClinicalTrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP)) together with reference checking, citation searching and contact with study authors to identify additional studies.

SELECTION CRITERIA

We sought randomised, double-blind, controlled trials of adults undergoing surgery under general anaesthesia and being treated with perioperative intravenous ketamine. Studies compared ketamine with placebo, or compared ketamine plus a basic analgesic, such as morphine or non-steroidal anti-inflammatory drug (NSAID), with a basic analgesic alone.

DATA COLLECTION AND ANALYSIS

Two review authors searched for studies, extracted efficacy and adverse event data, examined issues of study quality and potential bias, and performed analyses. Primary outcomes were opioid consumption and pain intensity at rest and during movement at 24 and 48 hours postoperatively. Secondary outcomes were time to first analgesic request, assessment of postoperative hyperalgesia, central nervous system (CNS) adverse effects, and postoperative nausea and vomiting. We assessed the evidence using GRADE and created a 'Summary of findings' table.

MAIN RESULTS

We included 130 studies with 8341 participants. Ketamine was given to 4588 participants and 3753 participants served as controls. Types of surgery included ear, nose or throat surgery, wisdom tooth extraction, thoracotomy, lumbar fusion surgery, microdiscectomy, hip joint replacement surgery, knee joint replacement surgery, anterior cruciate ligament repair, knee arthroscopy, mastectomy, haemorrhoidectomy, abdominal surgery, radical prostatectomy, thyroid surgery, elective caesarean section, and laparoscopic surgery. Racemic ketamine bolus doses were predominantly 0.25 mg to 1 mg, and infusions 2 to 5 µg/kg/minute; 10 studies used only S-ketamine and one only R-ketamine. Risk of bias was generally low or uncertain, except for study size; most had fewer than 50 participants per treatment arm, resulting in high heterogeneity, as expected, for most analyses. We did not stratify the main analysis by type of surgery or any other factor, such as dose or timing of ketamine administration, and used a non-stratified analysis.Perioperative intravenous ketamine reduced postoperative opioid consumption over 24 hours by 8 mg morphine equivalents (95% CI 6 to 9; 19% from 42 mg consumed by participants given placebo, moderate-quality evidence; 65 studies, 4004 participants). Over 48 hours, opioid consumption was 13 mg lower (95% CI 10 to 15; 19% from 67 mg with placebo, moderate-quality evidence; 37 studies, 2449 participants).Perioperative intravenous ketamine reduced pain at rest at 24 hours by 5/100 mm on a visual analogue scale (95% CI 4 to 7; 19% lower from 26/100 mm with placebo, high-quality evidence; 82 studies, 5004 participants), and at 48 hours by 5/100 mm (95% CI 3 to 7; 22% lower from 23/100 mm, high-quality evidence; 49 studies, 2962 participants). Pain during movement was reduced at 24 hours (6/100 mm, 14% lower from 42/100 mm, moderate-quality evidence; 29 studies, 1806 participants), and 48 hours (6/100 mm, 16% lower from 37 mm, low-quality evidence; 23 studies, 1353 participants).Results for primary outcomes were consistent when analysed by pain at rest or on movement, operation type, and timing of administration, or sensitivity to study size and pain intensity. No analysis by dose was possible. There was no difference when nitrous oxide was used. We downgraded the quality of the evidence once if numbers of participants were large but small-study effects were present, or twice if numbers were small and small-study effects likely but testing not possible.Ketamine increased the time for the first postoperative analgesic request by 54 minutes (95% CI 37 to 71 minutes), from a mean of 39 minutes with placebo (moderate-quality evidence; 31 studies, 1678 participants). Ketamine reduced the area of postoperative hyperalgesia by 7 cm² (95% CI -11.9 to -2.2), compared with placebo (very low-quality evidence; 7 studies 333 participants). We downgraded the quality of evidence because of small-study effects or because the number of participants was below 400.CNS adverse events occurred in 52 studies, while 53 studies reported of absence of CNS adverse events. Overall, 187/3614 (5%) participants receiving ketamine and 122/2924 (4%) receiving control treatment experienced an adverse event (RR 1.2, 95% CI 0.95 to 1.4; high-quality evidence; 105 studies, 6538 participants). Ketamine reduced postoperative nausea and vomiting from 27% with placebo to 23% with ketamine (RR 0.88, 95% CI 0.81 to 0.96; the number needed to treat to prevent one episode of postoperative nausea and vomiting with perioperative intravenous ketamine administration was 24 (95% CI 16 to 54; high-quality evidence; 95 studies, 5965 participants).

AUTHORS' CONCLUSIONS

Perioperative intravenous ketamine probably reduces postoperative analgesic consumption and pain intensity. Results were consistent in different operation types or timing of ketamine administration, with larger and smaller studies, and by higher and lower pain intensity. CNS adverse events were little different with ketamine or control. Perioperative intravenous ketamine probably reduces postoperative nausea and vomiting by a small extent, of arguable clinical relevance.