Prolonged Perioperative Use of Pregabalin and Ketamine to Prevent Persistent Pain after Cardiac Surgery

Effect of esketamine combined with pregabalin on acute postsurgical pain in patients who underwent resection of spinal neoplasms: a randomized controlled trial

ABSTRACT

Moderate-to-severe acute postsurgical pain (APSP) can prolong the recovery and worsen the prognosis of patients who undergo spinal surgery. Esketamine and pregabalin may resolve APSP without causing hyperpathia or respiratory depression after surgery. However, there are other risks, such as dissociative symptoms. We designed a randomized controlled trial to investigate the effect of the combination of these 2 drugs on the incidence of APSP in patients who underwent resection of spinal neoplasms. Patients aged 18 to 65 years were randomized to receive esketamine (a bolus dose of 0.5 mg·kg-1 and an infusion dose of 0.12 mg·kg-1·h-1 for 48 hours after surgery) combined with oral pregabalin (75-150 mg/day, starting 2 hours before surgery and ending at 2 weeks after surgery) or an identical volume of normal saline and placebo capsules. The primary outcome was the proportion of patients with moderate-to-severe APSP (visual analog scale score ≥ 40) during the first 48 hours after surgery. Secondary outcomes included the incidence of drug-related adverse events. A total of 90 patients were randomized. The incidence of moderate-to-severe APSP in the combined group (27.3%) was lower than that in the control group (60.5%) during the first 48 hours after surgery (odds ratio = 0.25, 95% CI = 0.10-0.61; P = 0.002). The occurrence of mild dissociative symptoms was higher in the combined group than in the control group (18.2% vs 0%). In conclusion, esketamine combined with pregabalin could effectively alleviate APSP after spinal surgery, but an analgesic strategy might increase the risk of mild dissociative symptoms.

Efficacy and safety of perioperative ketamine for the prevention of chronic postsurgical pain: A meta-analysis

STUDY OBJECTIVE

Assessment of the efficacy and safety of perioperative intravenous ketamine in reducing incidence and severity of chronic postsurgical pain.

STUDY DESIGN

A systematic review and meta-analysis of randomized controlled trials (RCTs).

DATA SOURCES

The following data sources were systematically searched: MEDLINE, CENTRAL, and EMBASE (till 02/2021).

PATIENTS

Adult patients undergoing any surgery.

INTERVENTIONS

Perioperative use of intravenous ketamine as an additive analgesic drug compared to placebo, no active control treatment, and other additive drugs.

MEASUREMENTS

Primary outcomes were number of patients with chronic postsurgical pain after 6 months and ketamine related adverse effects. Secondary outcomes were chronic postsurgical pain incidence after 3 and 12 months, chronic postsurgical neuropathic pain incidence, chronic postsurgical moderate to severe pain incidence, intensity of chronic postsurgical pain at rest, and during movement, oral morphine consumption after 3, 6, and 12 months and incidence of opioid-related adverse effects.

MAIN RESULTS

Thirty-six RCTs were included with a total of 3572 patients. Ketamine compared to placebo may result in no difference in the number of patients with chronic postsurgical pain after 6 months (risk ratio (RR) 0.86, 95% confidence interval (CI) 0.71-1.05; I2  = 34%; 16 studies; low-certainty evidence). Ketamine may reduce the incidence of chronic postsurgical neuropathic pain after 3 months in comparison to placebo (RR 0.78, 95% CI 0.62-0.99, I2  = 31%, seven trials, low-certainty evidence). Ketamine compared to placebo may increase the risk for postoperative nystagmus (RR 9.04, 95% CI 1.15-70.90, I2 30%, two trials, low-certainty evidence) and postoperative visual disturbances (RR 2.29, 95% CI 1.05-4.99, I2 10%, seven trials, low-certainty evidence).

CONCLUSIONS

There is low-certainty evidence that perioperative ketamine has no effect on chronic postsurgical pain in adult patients. Low-certainty evidence suggests that ketamine compared to placebo may reduce incidence of chronic postsurgical neuropathic pain after 3 months. Questions like ideal dosing, treatment duration and more patient-related outcome measures remain unanswered, which warrants further studies.

PROTOCOL REGISTRATION

Prospero CRD42021223625, 07.01.2021.

The impact of ketamine on outcomes in critically ill patients: a systematic review with meta-analysis and trial sequential analysis of randomized controlled trials

BACKGROUND

This meta-analysis aims to evaluate the effects of ketamine in critically ill intensive care unit (ICU) patients.

METHODS

We searched for randomized controlled trials (RCTs) in PubMed, Scopus, and the Cochrane Library; the search was performed initially in January but was repeated in December of 2023. We focused on ICU patients of any age. We included studies that compared ketamine with other traditional agents used in the ICU. We synthesized evidence using RevMan v5.4 and presented the results as forest plots. We also used trial sequential analysis (TSA) software v. 0.9.5.10 Beta and presented results as TSA plots. For synthesizing results, we used a random-effects model and reported differences in outcomes of two groups in terms of mean difference (MD), standardized MD, and risk ratio with 95% confidence interval. We assessed the risk of bias using the Cochrane RoB tool for RCTs. Our outcomes were mortality, pain, opioid and midazolam requirements, delirium rates, and ICU length of stay.

RESULTS

Twelve RCTs involving 805 ICU patients (ketamine group, n=398; control group, n=407) were included in the meta-analysis. The ketamine group was not superior to the control group in terms of mortality (in five studies with 318 patients), pain (two studies with 129 patients), mean and cumulative opioid consumption (six studies with 494 patients), midazolam consumption (six studies with 304 patients), and ICU length of stay (three studies with 270 patients). However, the model favored the ketamine group over the control group in delirium rate (four studies with 358 patients). This result is significant in terms of conventional boundaries (alpha=5%) but is not robust in sequential analysis. The applicability of the findings is limited by the small number of patients pooled for each outcome.

CONCLUSIONS

Our meta-analysis did not demonstrate differences between ketamine and control groups regarding any outcome except delirium rate, where the model favored the ketamine group over the control group. However, this result is not robust as sensitivity analysis and trial sequential analysis suggest that more RCTs should be conducted in the future.

Perioperative Implementation of Low-Dose Pregabalin in an Enhanced Recovery After Cardiac Surgery Protocol: A Pre-Post Observational Study

OBJECTIVES

Determine the effect of low-dose pregabalin in the perioperative enhanced recovery after cardiac surgery protocol.

DESIGN

Pre-post observational study.

SETTING

Tertiary care hospital.

PARTICIPANTS

Patients undergoing off-pump coronary artery bypass graft procedures.

INTERVENTIONS

Pregabalin 75 mg BID for 48 hours postoperatively versus no pregabalin in a perioperative setting.

MEASUREMENTS AND MAIN RESULTS

Perioperative opioid use, pain scores, length of stay, time to extubation, and mortality were all measured. Descriptive data were presented as mean (SD), median (IQR), or N (%). Ordinal and continuous data used the t-test or Kruskal-Wallis test. Categorical data were compared between groups using the chi-square test or Fisher's exact test, as appropriate. Low-dose pregabalin administration (75 mg twice daily for 48 hours after surgery) was associated with a clinically significant reduction in opioid consumption on postoperative day 0 by 30.6%, with a median requirement of 318 (233, 397) morphine milligram equivalents (MME) in the pregabalin group compared with 458 (375, 526) MME in the control group (p < 0.001). There was no significant difference in pain scores between the groups with the exception at 0-to-12 hours, during which the pregabalin group had greater pain scores (median 3.32 [1.65, 4.36] v 2.0 [0, 3.25], p = 0.013) (Table 3). Moreover, there was no significant difference in pain scores on postoperative day 1 (p = 0.492), day 2 (p = 0.442), day 3 (p = 0.237), and day 4 (p = 0.649). The difference in average Richmond Agitation Sedation Score scores was also not statistically significant between groups at 12 hours (p = 0.954) and at 24 hours (p = 0.301). The pregabalin group had no increased incidence of adverse events or any significant differences in intensive care unit length of stay, time to extubation, or mortality.

CONCLUSIONS

In this evaluation of perioperative pregabalin administration for patients requiring cardiac surgery, pregabalin reduced postoperative opioid use, with significant reductions on postoperative day 0, and without any significant increase in adverse reactions. However, no differences in intensive care unit length of stay, time to extubation, or mortality were noted. The implementation of low-dose perioperative pregabalin within an Enhanced Recovery After Cardiac Surgery protocol may be effective at reducing postoperative opioid use in the immediate postoperative period, and may be safe with regard to adverse events. Ideal dosing strategies have not been determined; thus, further randomized control trials with an emphasis on limiting confounding factors need to be conducted.

Ketamine as adjunctive or monotherapy for post-intubation sedation in patients with trauma on mechanical ventilation: A rapid review

Background

The effectiveness of ketamine as adjunctive or monotherapy for post-intubation sedation in adults with trauma on mechanical ventilation is unclear.

Methods

A rapid review of systematic reviews of randomized controlled trials, then randomized controlled trials or observational studies was conducted searching three electronic databases (PubMed, Embase, Cochrane Library) and one clinical trial registry on June 1, 2022. We used a prespecified protocol following Cochrane rapid review methods.

Results

We identified eight systematic reviews of randomized controlled trials and observational studies. Among the included reviews, only the most relevant, up to date, highest quality-assessed reviews and reviews that reported on critical outcomes were considered. Adjunctive ketamine showed a morphine sparing effect (MD -13.19 µmg kg-1 h-1, 95 % CI -22.10 to -4.28, moderate certainty of evidence, 6 RCTs), but no to little effect on midazolam sparing effect (MD 0.75 µmg kg-1 h-1, 95 % CI -1.11 to 2.61, low certainty of evidence, 6 RCTs) or duration of mechanical ventilation in days (MD -0.17 days, 95 % CI -3.03 to 2.69, moderate certainty of evidence, 3 RCTs).Adjunctive ketamine therapy may reduce mortality (OR 0.88, 95 % CI 0.54 to 1.43, P = 0.60, very low certainty of evidence, 5 RCTs, n = 3076 patients) resulting in 30 fewer deaths per 1000, ranging from 132 fewer to 87 more, but the evidence is very uncertain. Ketamine results in little to no difference in length of ICU stay (MD 0.04 days, 95 % CI -0.12 to 0.20, high certainty of evidence, 5 RCTs n = 390 patients) or length of hospital stay (MD -0.53 days, 95 % CI -1.36 to 0.30, high certainty of evidence, 5 RCTs, n = 277 patients).Monotherapy may have a positive effect on respiratory and haemodynamic outcomes, however the evidence is very uncertain.

Conclusion

Adjunctive ketamine for post-intubation analgosedation results in a moderate meaningful net benefit but there is uncertainty for benefit and harms as monotherapy.

Practice Advisory for Preoperative and Intraoperative Pain Management of Cardiac Surgical Patients: Part 2

Pain after cardiac surgery is of moderate to severe intensity, which increases postoperative distress and health care costs, and affects functional recovery. Opioids have been central agents in treating pain after cardiac surgery for decades. The use of multimodal analgesic strategies can promote effective postoperative pain control and help mitigate opioid exposure. This Practice Advisory is part of a series developed by the Society of Cardiovascular Anesthesiologists (SCA) Quality, Safety, and Leadership (QSL) Committee's Opioid Working Group. It is a systematic review of existing literature for various interventions related to the preoperative and intraoperative pain management of cardiac surgical patients. This Practice Advisory provides recommendations for providers caring for patients undergoing cardiac surgery. This entails developing customized pain management strategies for patients, including preoperative patient evaluation, pain management, and opioid use-focused education as well as perioperative use of multimodal analgesics and regional techniques for various cardiac surgical procedures. The literature related to this field is emerging, and future studies will provide additional guidance on ways to improve clinically meaningful patient outcomes.

Perioperative Administration of Pregabalin and Esketamine to Prevent Chronic Pain After Breast Cancer Surgery: A Randomized Controlled Trial

Background

Perioperative multimodal analgesia can prevent chronic pain after breast cancer surgery. This study aimed to investigate the efficacy of combined perioperative oral pregabalin and postoperative esketamine in preventing chronic pain after breast cancer surgery.

Methods

Ninety patients undergoing elective breast cancer surgery were randomized into the combined pregabalin and esketamine group (EP group) and the general anesthesia alone group (Control group). The EP group received 150 mg of oral pregabalin 1 h before surgery and twice daily for seven days postoperatively, and a patient-controlled analgesia pump after surgery that delivered 100 μg sufentanil + 1.25 mg/kg esketamine + 4 mg tropisetron in 100 mL saline solution intravenously. The Control group received placebo capsules before and after the surgery and routine postoperative analgesia (100 μg sufentanil + 4 mg tropisetron in 100 mL saline solution). The primary outcome was the incidence of chronic pain three and six months after surgery. Secondary outcomes included acute postoperative pain, postoperative opioid consumption, and incidence of adverse events.

Results

The incidence of chronic pain in the EP group was significantly lower than in the Control group three (14.3% vs 46.3%, P = 0.005) and six (7.1% vs 31.7%, P = 0.009) months postoperatively. The rest numerical rating scale (NRS) pain scores 1-3 days postoperatively and coughing NRS pain scores 1-7 days postoperatively in the EP group were significantly lower than in the Control group (all P ˂ 0.05). The cumulative sufentanil consumption in the EP group during postoperative 0-12, 12-24, and 24-48, 0-24, and 0-48 hours were significantly lower than in the Control group (all P ˂ 0.05).

Conclusion

Combined perioperative oral pregabalin and postoperative esketamine effectively prevented chronic pain after breast cancer surgery, improved acute postoperative pain, and reduced postoperative opioid consumption.

Evaluation of the Effect of New Multimodal Analgesia Regimen for Cardiac Surgery: A Prospective, Randomized Controlled, Single-Center Clinical Study

Objective

To investigate the feasibility of multimodal regimen by paracetamol, gabapentin, ketamine, lidocaine, dexmedetomidine and sufentanil among cardiac surgery patients, and compare the analgesia efficacy with conventional sufentanil-based regimen.

Design

A single-center, prospective, randomized, controlled clinical trial.

Setting

One participating center, the cardiovascular center of the major integrated teaching hospital.

Participants

A total of 115 patients were assessed for eligibility: 108 patients were randomized, 7 cases were excluded.

Interventions

The control group (group T) received conventional anesthesia management. Interventions in the multimodal group (group M) were as follows in addition to the standard of care: gabapentin and acetaminophen 1 hour before surgery; ketamine for induction and to maintain anesthesia with lidocaine and dexmedetomide. Ketamine, lidocaine, and dexmedetomidine were added to routine sedatives postoperatively in group M.

Measurements and Main Results

The incidence of moderate-to-severe pain on coughing made no significant difference (68.5% vs 64.8%, P=0.683). Group M had significantly less sufentanil use (135.72µg vs 94.85µg, P=0.000) and lower rescue analgesia rate (31.5% vs 57.4%, P=0.007). There was no significant difference in the incidence of chronic pain, PONV, dizziness, inflammation index, mechanical ventilation time, length of stay, and complications between the two groups.

Conclusion

Our multimodal regimen in cardiac surgery is feasible, but was not superior to traditional sufentanil-based regimen in the aspects of analgesia effects; however, it did reduce perioperative opioid consumption along with rescue analgesia rate. Moreover, it showed the same length of stay and the incidences of postoperative complications.

Prevalence and risk factors of significant persistent pain symptoms after critical care illness: a prospective multicentric study

BACKGROUND

Prevalence, risk factors and medical management of persistent pain symptoms after critical care illness have not been thoroughly investigated.

METHODS

We performed a prospective multicentric study in patients with an intensive care unit (ICU) length of stay ≥ 48 h. The primary outcome was the prevalence of significant persistent pain, defined as a numeric rating scale (NRS) ≥ 3, 3 months after admission. Secondary outcomes were the prevalence of symptoms compatible with neuropathic pain (ID-pain score > 3) and the risk factors of persistent pain.

RESULTS

Eight hundred fourteen patients were included over a 10-month period in 26 centers. Patients had a mean age of 57 (± 17) years with a SAPS 2 score of 32 (± 16) (mean ± SD). The median ICU length of stay was 6 [4-12] days (median [interquartile]). At 3 months, the median intensity of pain symptoms was 2 [1-5] in the entire population, and 388 (47.7%) patients had significant pain. In this group, 34 (8.7%) patients had symptoms compatible with neuropathic pain. Female (Odds Ratio 1.5 95% CI [1.1-2.1]), prior use of anti-depressive agents (OR 2.2 95% CI [1.3-4]), prone positioning (OR 3 95% CI [1.4-6.4]) and the presence of pain symptoms on ICU discharge (NRS ≥ 3) (OR 2.4 95% CI [1.7-3.4]) were risk factors of persistent pain. Compared with sepsis, patients admitted for trauma (non neuro) (OR 3.5 95% CI [2.1-6]) were particularly at risk of persistent pain. Only 35 (11.3%) patients had specialist pain management by 3 months.

CONCLUSIONS

Persistent pain symptoms were frequent in critical illness survivors and specialized management remained infrequent. Innovative approaches must be developed in the ICU to minimize the consequences of pain.

TRIAL REGISTRATION

NCT04817696. Registered March 26, 2021.

Esketamine combined with pregabalin on acute postoperative pain in patients undergoing resection of spinal neoplasms: study protocol for a randomized controlled trial

BACKGROUND

Perioperative pain management is one of the most challenging issues for patients with spinal neoplasms. Inadequate postoperative analgesia usually leads to severe postsurgical pain, which could cause patients to suffer from many other related complications. Meanwhile, there is no appropriate analgesic strategy for patients with spinal neoplasms.

METHODS/DESIGN

This is a protocol for a randomized double-blind controlled trial to evaluate the effect of esketamine combined with pregabalin on postsurgical pain in spinal surgery. Patients aged 18 to 65 years scheduled for spinal neoplasm resection will be randomly allocated into the combined and control groups in a 1:1 ratio. In the combined group, esketamine will be given during the during the surgery procedure until 48-h postoperative period, and pregabalin will be taken from 2 h before the surgery to 2 weeks postoperatively. The control group will receive normal saline and placebo capsules at the same time points. Both groups received a background analgesic regimen by using patient-controlled intravenous analgesia (containing 100 μg sufentanil and 16 mg ondansetron) until 2 days after surgery. To ensure the accuracy and reliability of this trial, all the researchers and patients will be blinded until the completion of this study. The primary outcome will be the proportion of patients with acute moderate-to-severe postsurgical pain (visual analog scale, VAS ≥ 40, range: 0-100, with 0, no pain; 100, the worst pain) during the 48-h postoperative period. The secondary outcomes will include the maximal VAS scores (when the patients felt the most intense pain over the last 24 h before being interviewed) at 0-2 h, 2-24 h, 24-48 h, and 48-72 h after leaving the operating room and 24 h before discharge; the incidence of acute moderate-to-severe postsurgical pain at each other time point; chronic postsurgical pain assessment; neuropathic pain assessment; and the incidence of drug-related adverse events and other postoperative complications, such as postoperative delirium and postoperative nausea and vomiting (PONV).

DISCUSSION

The aim of this study was to evaluate the effect of esketamine combined with pregabalin on acute postsurgical pain in patients undergoing resection of spinal neoplasms. The safety of this perioperative pain management strategy will also be examined.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05096468. Registered on October 27, 2021.

Integrating mechanistic-based and classification-based concepts into perioperative pain management: an educational guide for acute pain physicians

Chronic pain begins with acute pain. Physicians tend to classify pain by duration (acute vs chronic) and mechanism (nociceptive, neuropathic and nociplastic). Although this taxonomy may facilitate diagnosis and documentation, such categories are to some degree arbitrary constructs, with significant overlap in terms of mechanisms and treatments. In clinical practice, there are myriad different definitions for chronic pain and a substantial portion of chronic pain involves mixed phenotypes. Classification of pain based on acuity and mechanisms informs management at all levels and constitutes a critical part of guidelines and treatment for chronic pain care. Yet specialty care is often siloed, with advances in understanding lagging years behind in some areas in which these developments should be at the forefront of clinical practice. For example, in perioperative pain management, enhanced recovery protocols are not standardized and tend to drive treatment without consideration of mechanisms, which in many cases may be incongruent with personalized medicine and mechanism-based treatment. In this educational document, we discuss mechanisms and classification of pain as it pertains to commonly performed surgical procedures. Our goal is to provide a clinical reference for the acute pain physician to facilitate pain management decision-making (both diagnosis and therapy) in the perioperative period.

The impact of a postoperative multimodal analgesia pathway on opioid use and outcomes after cardiothoracic surgery

OBJECTIVE

The Enhanced Recovery after Surgery Cardiac Society recommends using multimodal analgesia (MMA) for postoperative pain however, evidence-based guidelines have yet to be established. This study examines the impact of a standardized postoperative MMA pathway in reducing opioid consumption and related complications after cardiothoracic surgery (CTS).

METHODS

Within a multicenter healthcare system, a postoperative MMA pathway was developed and implemented at two CTS intensive care units (ICU) while the other CTS ICU opted to maintain the existing opioid-based pathway. A retrospective chart review was conducted on patients admitted to a CTS ICU within this healthcare system after conventional coronary artery bypass grafting and/or valve surgery from September 1, 2018, to June 30, 2019. Comparative analysis was conducted on patients prescribed MMA versus those managed with an opioid-based pathway. The primary outcome was total opioid consumption, converted to morphine milligram equivalents, 72-h post-surgery. Secondary outcomes included mobility within one-day post-surgery, ICU length of stay (LOS), time to first bowel movement (BM), and time to first zero Richmond Agitation-Sedation Scale (RASS).

RESULTS

Seven hundred sixty-two adults were included for final analysis. The MMA group had a higher body mass index, higher percentage of females, were more likely classified as African American and had higher scores for risk-adjusted complications. General Linear Model analysis revealed higher opioid consumption in the MMA group (Est. 0.22, p < 0.0009); however, this was not statistically significant after adjusting for differences in fentanyl usage. The MMA group was more likely to have mobility within one-day post-surgery (OR 0.44, p < 0.0001), have longer time to first BM (OR 1.93, p = 0.0011), and longer time to first zero RASS (OR 1.62, p = 0.0071). The analgesia groups were not a predictor for ICU LOS.

CONCLUSIONS

Opioid consumption was not reduced secondary to this postoperative MMA pathway. The MMA group was more likely to have mobility within one-day post-surgery. Patients in the MMA group were also more likely to have prolonged time to first BM and first zero RASS. Development and evaluation of a perioperative MMA pathway should be considered.

Gabapentinoid Use in Perioperative Care and Current Controversies

PURPOSE OF REVIEW

This review summarizes the risks and benefits of gabapentinoids (gabapentin and pregabalin) for perioperative pain control and the controversies surrounding their use in a variety of settings. We review current literature with the goal of providing patient-centric and procedure-specific recommendations for the use of these medications.

RECENT FINDINGS

Gabapentinoids are among the most prescribed medications in the USA, and typically for off-label indications such as postoperative pain. In the perioperative setting, multimodal analgesic or "opioid-sparing" regimens have become the standard of care-and some clinical protocols include gabapentinoids. At the same time, guidelines regarding the perioperative use of gabapentinoids are conflicting and evidence supporting their broad use is lacking. Gabapentinoids administered perioperatively reduce opioid requirements and pain scores for a variety of surgeries. The extent of opioid and pain reduction, however, is not always clinically significant. These medications reduce postoperative nausea and vomiting as well as pruritis, likely as a feature of reducing opioid intake, but are associated with side effects such as dizziness, ataxia, and cognitive dysfunction. Gabapentinoids also increase the risk of respiratory depression, in particular when paired with opioids. There is thus evidence suggesting that the routine use of these medications for perioperative pain management is not recommended. An individualized, patient- and surgery-specific approach should be used, although research is still needed to determine risks and benefits during perioperative use.

Impact of Ketamine on Analgosedative Consumption in Critically Ill Patients: A Systematic Review and Meta-Analysis

Objective:

The aim of this study was to synthesize evidence available on continuous infusion ketamine versus nonketamine regimens for analgosedation in critically ill patients.

Data sources

A search of MEDLINE, EMBASE, CINAHL, CDSR, and ClinicalTrials.gov was performed from database establishment to November 2021 using the following search terms: critical care, ICU, ketamine, sedation, and anesthesia. All studies included the primary outcome of interest: daily opioid and/or sedative consumption.

Study selection and data extraction

Relevant human studies were considered. Randomized controlled trials (RCT), quasi-experimental studies, and observational cohort studies were eligible. Two reviewers independently screened articles, extracted data, and appraised studies using the Cochrane RoB and ROBINS-I tools.

Data synthesis

A total of 13 RCTs, 5 retrospective, and 1 prospective cohort study were included (2255 participants). The primary analysis of six RCTs demonstrated reduced opioid consumption with ketamine regimens (n = 494 participants, −13.19 µg kg⁻¹ h⁻¹ morphine equivalents, 95% CI −22.10 to −4.28, P = 0.004). No significant difference was observed in sedative consumption, duration of mechanical ventilation (MV), ICU or hospital length of stay (LOS), intracranial pressure, and mortality. Small sample size of studies may have limited ability to detect true differences between groups.

Relevance to patient care and clinical practice

This meta-analysis examining ketamine use in critically ill patients is the first restricting analysis to RCTs and includes up-to-date publication of trials. Findings may guide clinicians in consideration and dosing of ketamine for multimodal analgosedation.

Conclusion

Results suggest ketamine as an adjunct analgosedative has the potential to reduce opioid exposure in postoperative and MV patients in the ICU. More RCTs are required before recommending routine use of ketamine in select populations.

Evaluation of Different Pain-Control Procedures for Post-cardiac Surgery: A Systematic Review and Network Meta-Analysis

Objective

To identify superior pain-control procedures for postoperative patients who undergo cardiac surgeries.

Methods

Literature searches were conducted in globally recognized databases, including MEDLINE, EMBASE and Cochrane Central, to identify randomized controlled trials (RCTs) investigating pain-control procedures after cardiac surgeries. The parameters evaluating analgesic efficacy and postoperative recovery, namely, the pain score and ICU stay, were quantitatively pooled and estimated using Bayesian methods. The values of the surface under the cumulative ranking (SUCRA) probabilities regarding each parameter were calculated to enable the ranking of various pain-control procedures. Node-splitting analysis was performed to test the inconsistency of the main results, and the publication bias was assessed by examining the funnel-plot symmetry.

Results

After a detailed review, 13 RCTs containing 7 different procedures were included in the network meta-analysis. After pooling the results together, an erector spinae plane block (ESPB) and a local parasternal block (LPB) plus target-controlled infusion (TCI) presented the best analgesic effects for reducing pain at rest (SUCRA, .47) and during movement (SUCRA, .52), respectively, while the former also achieved the shortest ICU stay (SUCRA, .48). Moreover, the funnel-plot symmetries showed no inconsistencies or obvious publication bias in the current study.

Conclusions

The current evidence indicates that ESPB is a potential superior analgesic strategy for post-cardiac surgery patients. To verify this conclusion further, it is imperative to obtain more high-quality evidence and conduct relevant investigations in the future.

Persistent Opioid Use After Open Aortic Surgery: Risk Factors, Costs, and Consequences

BACKGROUND

The incidence and financial impact of persistent opioid use (POU) after open aortic surgery is undefined.

METHODS

Insurance claim data from opioid-naïve patients who underwent aortic root replacement, ascending aortic replacement, or transverse arch replacement from 2011 to 2017 were evaluated. POU was defined as filling an opioid prescription in the perioperative period and between 90 and 180 days postoperatively. Postoperative opioid prescriptions, emergency department visits, readmissions, and health care costs were quantified. Multivariable logistic regression identified risk factors for POU, and quantile regression quantified the impact of POU on postoperative health care costs.

RESULTS

Among 3240 opioid-naïve patients undergoing open aortic surgery, 169 patients (5.2%) had POU. In the univariate analysis, patients with POU were prescribed more perioperative opioids (375 vs 225 morphine milligram equivalents, P < .001), had more emergency department visits (45.6% vs 25.4%, P < .001), and had significantly higher health care payments in the 6 months postoperatively ($10,947 vs $7223, P < .001). Independent risk factors for POU in the multivariable logistic regression included preoperative nicotine use and more opioids in the first perioperative prescription (all P < .05). After risk adjustment, POU was associated with a $2439 increase in total health care costs in the 6 months postoperatively.

CONCLUSIONS

POU is a challenge after open aortic operations and can have longer-term impacts on health care payments and emergency department visits in the 6 months after surgery. Strategies to reduce outpatient opioid use after aortic surgery should be encouraged when feasible.

Persistent and acute postoperative pain after cardiac surgery with anterolateral thoracotomy or median sternotomy: A prospective observational study

OBJECTIVE

The primary objective of this study was to compare the association between cardiac surgical approach (thoracotomy vs. sternotomy) and incidence of persistent postoperative pain at 3 months. Secondary objectives were the incidence and intensity of persistent pain at 6 and 12 months, acute postoperative pain, analgesic requirement and its side effects.

DESIGN

Single-center, prospective, observational study. Recruitment between December 2017 and August 2018.

SETTING

Perioperative care at university-affiliated tertiary care centre.

PATIENTS

202 adults scheduled for cardiac surgery. Patients with chronic pain or behavioural disorder were excluded.

INTERVENTIONS

Thoracotomy (n = 106) and sternotomy (n = 96).

MEASUREMENTS

Pain scores and pain medication requirements from extubation until hospital discharge. Persistent postoperative pain was assessed using a telephone questionnaire.

MAIN RESULTS

Incidence and intensity of pain was not significantly different between thoracotomy or sternotomy either in the short- or in the long-term follow-up. Incidence of persistent postoperative pain showed no differences between groups (30.2 vs 22.9% at 3 months (p = 0.297), 10.4 vs 7.3% at 6 months (p = 0.364) and 7.5 vs 7.3% at 12 months (p = 0.518) in thoracotomy and sternotomy group). A significant decrease of pain incidence was observed between 3 and 6 months (p < 0.001) but not between 6 and 12 months (p = 0.259) in both groups. ANOVA of repeated measures adjusted for confounding variable showed a decrease of acute pain intensity over time (p = 0.001) with no difference between groups (p = 0.145). Acute pain medication requirements were not different between the groups (p = 0.237 for piritramide and p = 0.743 for oxycodone) with no difference in their side effects.

CONCLUSIONS

Our study showed no difference in short- or long-term pain in patients undergoing anterolateral thoracotomy or median sternotomy. Both groups showed a decrease in persistent postoperative pain incidence between 3 and 6 months without any significant changes at 12 months.

Intrathecal Morphine for Analgesia in Minimally Invasive Cardiac Surgery: A Randomized, Placebo-controlled, Double-blinded Clinical Trial

BACKGROUND

Intrathecal morphine decreases postoperative pain in standard cardiac surgery. Its safety and effectiveness have not been adequately evaluated in minimally invasive cardiac surgery. The authors hypothesized that intrathecal morphine would decrease postoperative morphine consumption after minimally invasive cardiac surgery.

METHODS

In this randomized, placebo-controlled, double-blinded clinical trial, patients undergoing robotic totally endoscopic coronary artery bypass received either intrathecal morphine (5 mcg/kg) or intrathecal saline before surgery. The primary outcome was postoperative morphine equivalent consumption in the first 24 h after surgery; secondary outcomes included pain scores, side effects, and patient satisfaction. Pain was assessed via visual analog scale at 1, 2, 6, 12, 24, and 48 h after intensive care unit arrival. Opioid-related side effects (nausea/vomiting, pruritus, urinary retention, respiratory depression) were assessed daily. Patient satisfaction was evaluated with the Revised American Pain Society Outcome Questionnaire.

RESULTS

Seventy-nine patients were randomized to receive intrathecal morphine (n = 37) or intrathecal placebo (n = 42), with 70 analyzed (morphine 33, placebo 37). Intrathecal morphine patients required significantly less median (25th to 75th percentile) morphine equivalents compared to placebo during first postoperative 24 h (28 [16 to 46] mg vs. 59 [41 to 79] mg; difference, -28 [95% CI, -40 to -18]; P < 0.001) and second postoperative 24 h (0 [0 to 2] mg vs. 5 [0 to 6] mg; difference, -3.3 [95% CI, -5 to 0]; P < 0.001), exhibited significantly lower visual analog scale pain scores at rest and cough at all postoperative timepoints (overall treatment effect, -4.1 [95% CI, -4.9 to -3.3] and -4.7 [95% CI, -5.5 to -3.9], respectively; P < 0.001), and percent time in severe pain (10 [0 to 40] vs. 40 [20 to 70]; P = 0.003) during the postoperative period. Mild nausea was more common in the intrathecal morphine group (36% vs. 8%; P = 0.004).

CONCLUSIONS

When given before induction of anesthesia for totally endoscopic coronary artery bypass, intrathecal morphine decreases use of postoperative opioids and produces significant postoperative analgesia for 48 h.

EDITOR’S PERSPECTIVE

Impact of Ketamine on Opioid Use and Persistent Pain After Cytoreductive Surgery with Hyperthermic Chemotherapy

Background

Persistent pain and opioid use can be devastating after cytoreductive surgery (CRS) and hyperthermic intraoperative chemotherapy (HIPEC).

Methods

We conducted a retrospective study to investigate the impact of ketamine use on postoperative complications and persistent and chronic pain after CRS-HIPEC.

Results

Ketamine reduced perioperative opioid use before and after implementation of recovery after surgery programs. Ketamine did not impact the formation of persistent and chronic pain formation and long-term opioid use. Postoperative complications and postoperative re-operations were independent predictors of persistent pain. Interestingly, the risk of having a complication was increased by 1% for every doubling in opioids used intraoperatively.

Conclusion

Ketamine use reduces perioperative opioid consumption in patients undergoing CRS-HIPEC, but it is not associated with improvements in long-term opioid use and chronic pain.

Pharmacotherapy for the Prevention of Chronic Pain after Surgery in Adults: An Updated Systematic Review and Meta-analysis

BACKGROUND

Chronic postsurgical pain can severely impair patient health and quality of life. This systematic review update evaluated the effectiveness of systemic drugs to prevent chronic postsurgical pain.

METHODS

The authors included double-blind, placebo-controlled, randomized controlled trials including adults that evaluated perioperative systemic drugs. Studies that evaluated same drug(s) administered similarly were pooled. The primary outcome was the proportion reporting any pain at 3 or more months postsurgery.

RESULTS

The authors identified 70 new studies and 40 from 2013. Most evaluated ketamine, pregabalin, gabapentin, IV lidocaine, nonsteroidal anti-inflammatory drugs, and corticosteroids. Some meta-analyses showed statistically significant-but of unclear clinical relevance-reductions in chronic postsurgical pain prevalence after treatment with pregabalin, IV lidocaine, and nonsteroidal anti-inflammatory drugs. Meta-analyses with more than three studies and more than 500 participants showed no effect of ketamine on prevalence of any pain at 6 months when administered for 24 h or less (risk ratio, 0.62 [95% CI, 0.36 to 1.07]; prevalence, 0 to 88% ketamine; 0 to 94% placebo) or more than 24 h (risk ratio, 0.91 [95% CI, 0.74 to 1.12]; 6 to 71% ketamine; 5 to 78% placebo), no effect of pregabalin on prevalence of any pain at 3 months (risk ratio, 0.88 [95% CI, 0.70 to 1.10]; 4 to 88% pregabalin; 3 to 80% placebo) or 6 months (risk ratio, 0.78 [95% CI, 0.47 to 1.28]; 6 to 68% pregabalin; 4 to 69% placebo) when administered more than 24 h, and an effect of pregabalin on prevalence of moderate/severe pain at 3 months when administered more than 24 h (risk ratio, 0.47 [95% CI, 0.33 to 0.68]; 0 to 20% pregabalin; 4 to 34% placebo). However, the results should be interpreted with caution given small study sizes, variable surgical types, dosages, timing and method of outcome measurements in relation to the acute pain trajectory in question, and preoperative pain status.

CONCLUSIONS

Despite agreement that chronic postsurgical pain is an important topic, extremely little progress has been made since 2013, likely due to study designs being insufficient to address the complexities of this multifactorial problem.

EDITOR’S PERSPECTIVE

Seven-year follow-up of persistent postsurgical pain in cardiac surgery patients: A prospective observational study of prevalence and risk factors

BACKGROUND

Our aim was to describe the long-term prevalence, risk factors and impact on quality of life of persistent postsurgical pain (PPP) following cardiac surgery.

METHODS

All patients undergoing sternotomy in a single centre over 6 months were prospectively interviewed by telephone at six months and seven years following surgery.

RESULTS

We analysed data from 174 patients at six months and 146 patients at seven years following surgery, revealing a PPP prevalence of 39.7% (n = 69) and 9.6% (n = 14) respectively. At six post-operative months, younger age, higher acute pain score, intraoperative remifentanil infusion and more prolonged surgery were associated with sternotomy-site PPP. These variables, in combination, predict PPP in this study group with area under the receiver operating curve of 0.91 (95% CI 0.86-0.94) at 6 months and 0.74 (95% CI 0.57-0.86) at 7 years. Quality of life scores were significantly lower with PPP (median change in EQ-5D score = -0.23 [-0.57, -0.09] compared to 0.00 [0-0.24] without PPP at 7 years, p < 0.001). At7 years, younger age, prolonged surgery and intraoperative remifentanil infusion were associated with sternotomy-site PPP.

CONCLUSIONS

To the best of our knowledge, this is the longest follow-up of PPP across all surgical specialities and certainly within cardiac surgery. Prevalence of PPP and impact on QOL after cardiac surgery are high and associated with young age, high acute pain score, use of remifentanil and long operative time. We present a predictive score to highlight patients at risk of developing PPP.

SIGNIFICANCE

Seven years after cardiac surgery, almost 10% of patients in this cohort described persistent pain in and around the incision. While higher than previous reports in the literature (limited to up to five post-operative years), this assessment was made following three maximal coughs and therefore is movement or function evoked. High incident of persistent postsurgical pain may adversely affect long-term quality of life which is measured using a validated tool.

The expanding role of chronic pain interventions in multimodal perioperative pain management: a narrative review

Surgery is a risk factor for chronic pain and long-term opioid use. As perioperative pain management continues to evolve, treatment modalities traditionally used for chronic pain therapy may provide additional benefit to patients undergoing surgery. Interventions such as radiofrequency ablation, cryoneurolysis, and neuromodulation may potentially be used in conjunction with acute pain procedures such as nerve blocks and multimodal analgesia. Pharmacological agents associated with chronic pain medicine, including gabapentinoids, ketamine, and selective serotonin reuptake inhibitors, may be useful adjuncts in perioperative pain management when indicated. There may also be a role for acupuncture, music therapy, and other integrative medicine therapies. A transitional pain service can help coordinate outpatient care with inpatient perioperative pain management and promote a more personalized and comprehensive approach that can improve postoperative outcomes.

Efficiency and safety of pharmacotherapy for postoperative pain in cardiac surgery

Intraoperative injury with the formation of a sternotomy wound is inevitably accompanied by postoperative pain, which has a negative effect on the postoperative period and prognosis of patients. Today, moderate and severe pain affects at least half of patients in the early postoperative period after cardiac surgery. Inadequate pain relief in the early postoperative period can lead to chronic pain, which significantly reduces the quality of life of patients. The concept of multimodal analgesia with different painkillers is a priority, effective and safe technique both after cardiac surgery and in other areas of surgery. The current review article is devoted to the analysis of efficacy and safety of various drug groups for postoperative pain relief in cardiac surgery.

Oral Pregabalin in Cardiac Surgery: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background

Pregabalin has received wide clinical attention as a new type of analgesic. We undertake a systematic review and meta-analysis to evaluate the effect of pregabalin on postoperative pain in patients undergoing cardiac surgery.

Methods

We searched PubMed, Embase, and Cochrane Library (from inception to July 2020) for eligible studies. The primary outcomes were the total morphine consumption at 24 h. A secondary outcome was intraoperative fentanyl consumption, extubation time postoperative, and length of stay in hospital. We calculated pooled weighted mean difference (WMD) or odds ratio (OR) and 95% CIs using random- or fixed-effects models.

Results

Seven trials involving 463 patients were listed. Meta-analysis showed that the total morphine consumption at 24 h in the pregabalin group was significantly less than the control group (WMD: -5.44, 95% CI: -10.42–0.46, P = 0.03). We found that there is no significant difference between the two groups in intraoperative fentanyl consumption. Compared with the control group, the length of stay in hospital in the pregabalin group was significantly shorter (WMD = -0.87, 95% CI: -1.42−0.32, P = 0.002). And we found that there were no significant differences between the two groups in extubation time (WMD: 17.24, 95% CI: -24.36−58.84, P = 0.42).

Conclusions

Oral pregabalin for cardiac surgery patients can effectively reduce the patient's 24-hour morphine consumption after surgery, shorten the patient's hospital stay, and is more conducive to early postoperative recovery.

Anaesthetic considerations in polytrauma patients

Trauma remains a major public health concern due to the high cost, associated morbidity, and mortality both in developed and developing countries. Management of polytrauma patients has advanced and improved over the last few decades with a better understanding of the pathophysiology of shock, resuscitation, and hemodynamic changes. Anaesthesia and application of anaesthetic principles have consequently evolved and can be applied in polytrauma patients throughout their journey of treatment beginning from pre-hospital care, emergency department resuscitation, surgical procedures, and rehabilitation. Providing immediate pain relief is an important component in the management of these patients. Performing peripheral nerve blocks in the pre-hospital setting when feasible or on arrival in the emergency room provides rapid pain relief, better patient co-operation, decreases the risk of chronic pain syndromes. This narrative evaluates the role of anaesthesia and anaesthesiologists in the management of polytrauma patients. The authors performed a thorough review of the literature using various databased of Medline, PubMed, Embase, and Google Scholar. The relevant papers were also searched manually from the cross-referencing of retrieved papers. Full papers published in English till September 25, 2020 were included for this review. The keywords included 'trauma', 'difficult airway', 'anaesthesia', 'fluid and blood', 'monitoring', 'critical care', 'resuscitation' and 'surgery' in various combinations. The holistic management of trauma victims requires a multidisciplinary time-based approach for an optimal outcome. The management starts from assessment and simultaneous management for the optimization of the trauma victim from the first point of contact itself. The anaesthetic technique of choice in the perioperative management of trauma patients depends on different factors such as neurological status, cardiovascular stability, type and duration of surgery, coagulation status. Regional techniques are to be used whenever possible due to the beneficial effects observed with these techniques. Various important aspects are being discussed in subsequent sections.

Introduction of an Analgesia Prescription Guideline Can Reduce Unused Opioids After Cardiac Surgery: A Before and After Cohort Study

OBJECTIVE(S)

The authors aimed to assess whether the introduction of a tailored Analgesia Prescription Guideline would decrease the amount of unused opioid following discharge from cardiac surgery.

DESIGN

Prospective, observational, before and after study.

SETTING

Quaternary care university hospital.

PARTICIPANTS

A total of 191 participants who underwent cardiac surgery requiring midline sternotomy and cardiopulmonary bypass. There were 99 participants in the before cohort (prior to introduction of the Analgesia Prescription Guideline), and 92 participants in the after cohort (after introduction of the Analgesia Prescription Guideline).

INTERVENTIONS

Using prospectively collected observational data on participant opioid consumption in the before cohort, a tailored Analgesia Prescription Guideline was developed. This guideline then was introduced to all opioid-prescribing providers in the cardiothoracic surgery department. Prospective data then were collected in the after cohort of participants. Opioid prescription practices and opioid consumption between the two groups then were compared.

MEASUREMENTS AND MAIN RESULTS

Opioid prescriptions were given to 62/99 participants (63%) in the before cohort, and 48/92 (52%) in the after cohort (rate difference 0.1, CI 95% -0.26, 0.046). In the before cohort, the mean (± standard deviation) number of opioid tablets prescribed, used, and leftover was 26 (±10), 11 (±10), and 15 (±12), respectively. In the after cohort, the mean number of opioid tablets prescribed, used, and leftover was 18 (mean difference -8, CI 95% -12, -5), 10 (mean difference -1, CI 95% -5, 3), and 8 (mean difference -7, CI 95% -11, -3), respectively. There were 110/191 (58%) participants using no opioids following discharge, and 10/191 (5%) still using opioids two weeks after discharge. There were no differences between groups with regard to demographics, opioid-related side effects, pain scores, satisfaction, opioid storage. and disposal practices.

CONCLUSIONS

The development and implementation of a tailored Analgesia Prescription Guideline decreased the amount of opioids prescribed after cardiac surgery and resulted in lower numbers of unused leftover opioid tablets in the community. Patient comfort and satisfaction scores remained high.

Perioperative care in cardiac surgery

As mortality is now low for many cardiac surgical procedures, there has been an increasing focus on patient centered outcomes such as recovery and quality of life. The Enhanced Recovery After Surgery (ERAS) cardiac society recently published the first set of guidelines for cardiac surgery which will be useful as a starting point to help translate this philosophy for the benefit of those undergoing cardiac surgery. At the same time there are many advances in other areas such as mechanical circulation, diagnostics and quality metrics. We intend here to present a balanced and evidenced based review of selected aspects of current practice, encompassing both UK and international perioperative care with a focus on recent advances. For the convenience of the reader we will adopt the conventional perioperative preoperative, intraoperative and postoperative phases of care. The focus of cardiac surgical practice needs to evolve from mortality to recovery. Those specialists who work in cardiac anaesthesia and critical care are well placed to contribute to these changes. Accompanying this work is the development of technologies to improve recognition of and intervention to prevent early organ dysfunction. Measuring, benchmarking and publishing quality outcomes from cardiac surgical centres is likely to improve services and benefit our patients.

The PRECIS-2 tool seems not to be useful to discriminate the degree of pragmatism of medicine masked trials from that of open-label trials

PURPOSE

To assess, with all available trial information, whether the assessment of the PRECIS-2 nine domains could provide a clear distinction between medicine masked pragmatic randomized controlled trials (pRCTs) and open-label pRCTs.

METHODS

A search was conducted of participant-level pRCTs on medicines published on 25 influential medical journals in July 2018-December 2019. All pre-licensing (phases 1-3) and cluster pRCTs were excluded. All trials' available reports were searched through the published article information, Google Scholar, and trial websites. Instead of providing a score to each PRECIS-2 domain, these were classified as E (explanatory), N (neutral), or P (pragmatic).

RESULTS

Of 128 pRCTs, 18 (14%) were participant-level pRCTs on medicines. The full trial protocol was available for 14 trials; 12 had published the protocol and nine had additional reports published. All trials were prospectively registered, and none was funded by industry. Ten and eight were masked and open-label trials, respectively. Masked pRCTS had 34% of pragmatic and 60% of explanatory domains; open-label pRCTS had 45% pragmatic and 45% explanatory domains. Among the 10 masked trials, only one had a majority of five pragmatic domains; among the eight open-label trials, four had a majority of six or five pragmatic domains. "Follow-up" was considered explanatory in the 18 pRCTs; "primary analysis" was pragmatic in 17 pRCTs.

CONCLUSION

The PRECIS-2 tool seems not to be sensitive enough to clearly discriminate between medicine masked pRCTs and open-label pRCTs. When conducting systematic reviews, it is suggested that the PRECIS-2 tool should not be used to support placing masked trials in the pragmatic side of the explanatory/pragmatic continuum.

The Effect of Propofol Versus Volatile Anesthetics on Persistent Pain After Cardiac Surgery: A Randomized Controlled Trial

OBJECTIVES

Sternal incisions can generate persistent and intense post-sternotomy pain. Propofol has been shown to improve postoperative analgesia, but the preventive effect on persistent pain after cardiac surgery is unknown. The hypothesis of the present study was that intraoperative propofol-based anesthesia compared with volatile anesthesia could reduce the risk of chronic pain after cardiac surgery.

DESIGN

A single-center, two-arm, patient-and-evaluator-blinded, randomized controlled trial.

SETTING

A single major urban teaching and university hospital.

PATIENTS

Five-hundred adult patients undergoing cardiac surgery via sternotomy randomly were assigned. With six withdrawals from the study and five from surgery, 244 in the total intravenous anesthesia group and 245 in the volatile group were included in the modified intention-to-treat analysis.

INTERVENTIONS

Patients randomly were assigned to receive either propofol-based total intravenous anesthesia or volatile anesthesia during surgery.

MEASUREMENTS AND MAIN RESULTS

The primary outcomes were the incidence of pain at three, six, and 12 months after surgery defined as pain score >0 on the numeric rating scale. The secondary outcomes included acute pain, opioid use during the first 72 hours after surgery, and quality of life. The use of propofol did not significantly affect chronic pain at three months (55.4% v 52.9%, difference 2.5%, 95% confidence interval [CI] -6.6 to 11.6; p = 0.656), six months (35.5% v 37.5%, difference -2.0%, 95% CI -10.9 to 6.9; p = 0.657), or 12 months (18.2% v 20.7%, difference -2.5%, 95% CI -9.8 to 4.8; p = 0.495) compared with volatile anesthetics. Furthermore, there were no differences in acute pain score; morphine-equivalent consumption during the first 72 hours; and quality of life at three, six, and 12 months after surgery.

CONCLUSIONS

Intraoperative administration of propofol did not reduce persistent pain after cardiac surgery compared with volatile anesthetics.

Reducing Opioid Use in Patients Undergoing Cardiac Surgery - Preoperative, Intraoperative, and Critical Care Strategies

Patients undergoing cardiothoracic surgery are exposed to opioids in the operating room and intensive care unit and after hospital discharge. Opportunities exist to reduce perioperative opioid use at all stages of care and include alternative oral and intravenous medications, novel intraoperative regional anesthetic techniques, and postoperative opioid-sparing sedative and analgesic strategies. In this review, currently used and investigational strategies to reduce the opioid burden for cardiothoracic surgical patients are explored.

Quantitative Sensory Testing in pain assesment and treatment. Brief review and algorithmic management proposal

Quantitative Sensory Testing (QST) is used to globally analyze the nociceptive system in order to obtain a more objective understanding of pain perception. In recent years, QST has become a common tool in many pain clinics and anesthesiology departments worldwide. In 2013, the Neuropathic Pain Special Interest Group of the IASP put forward the first recommendations for conducting QST in clinical practice and research. However, the wide variety of QST methodologies and standards in the literature make it difficult to generalize the used of this tool in clinical practice. In this study, we present the basic concepts of QST, the type of tests and devices used, how they are applied, and the role of QST in anesthesiology and pain management.

N-Methyl-D-Aspartate Antagonists and Steroids for the Prevention of Persisting Post-Surgical Pain After Thoracoscopic Surgeries: A Randomized Controlled, Factorial Design, International, Multicenter Pilot Trial

Purpose

We conducted a feasibility 2×2 factorial trial comparing N-methyl-D-aspartate (NMDA) antagonists (intravenous ketamine and oral memantine) versus placebo and intravenous steroids versus placebo, in patients having elective video-assisted thoracic surgery lobectomies, at St. Joseph's Hamilton, Canada, and Cleveland Clinic, Cleveland, USA. Our feasibility objectives were: 1) recruitment rate/week; 2) recruitment of ≥90% of eligible patients; and 3) >90% follow-up. Secondary objectives were incidence and intensity of persistent post-surgical pain (PPSP) and other clinical and safety outcomes.

Methods

Using computerized randomization, patients were allocated to one of four groups: NMDA active with steroid placebo; NMDA placebo with steroid active; both NMDA and steroid active; both NMDA and steroid placebo. Patients, health providers, and data analysts were blinded to allocation. Patients were followed for 3 months after randomization.

Results

The trial was initiated in May 2017 at Hamilton and, after subsequent regulatory and ethics approval, in April 2018 at Cleveland. The trial had to be stopped after only 1 month of recruitment in Cleveland because the packaged study medications (memantine) expired and we were unable to procure the dosage required. Among 41 eligible patients, 27 (66%) were randomized. The recruitment rate/week was 0.63, 95% confidence interval (CI): 0.47-0.79 in Hamilton; and 1, 95% CI: 0.83-1.17 in Cleveland. Follow-up was complete for all 24 patients (100%) in Hamilton, and 3 of 4 patients in Cleveland. In total, only 4 patients (15%), and 2 patients (7%) had persistent pain at rest and with movement, respectively. There were no significant differences between groups for other outcomes.

Conclusion

The trial had to be stopped prematurely due to non-availability of study medications. Trial feasibility objectives of recruiting 90% of eligible patients and recruiting at least one patient/week per site were not met. Consideration for protocol changes will be necessary for the full trial.

Trial Registration

NCT02950233.