Intravenous versus Oral Acetaminophen for Pain: Systematic Review of Current Evidence to Support Clinical Decision-Making

Improving perioperative acetaminophen administration for safer and cost-effective multimodal analgesia in pediatric surgery: A QI initiative

BACKGROUND

The use of acetaminophen in the perioperative period has emerged as an attractive option for providing safer and cost-effective analgesia in children.

AIMS

The primary aim of our project was to increase the use of acetaminophen (both oral and intravenous) in the perioperative period from a baseline of 39.5% to 50% for all surgical patients within 24 months. The secondary aim was to increase the use of enteral acetaminophen from 10% to 52.5% during the same period.

METHODS

A multidisciplinary team was formed, and model for improvement was chosen as the QI methodology. The primary measure was the total percentage of surgical patients receiving any form of perioperative acetaminophen, while our secondary measure was the percentage use of oral acetaminophen administration. We also tracked the average maximum PACU (Post Anesthesia Care Unit) pain scores and the percentage of patients receiving IV opioids. Multiple interventions were conducted, including education, increasing the availability of acetaminophen, and optimizing the electronic medical record (EMR). Monthly data was collected using an automated report in the EMR.

RESULTS

We successfully achieved our goal, increasing the use of acetaminophen from 39.5% to 70% within four months. Despite some fluctuations, by the end of 24 months, we not only met but surpassed our goal, with 63% of patients receiving perioperative acetaminophen. Similarly, the usage of oral acetaminophen increased from a baseline of 10% to 78%. Our average maximum PACU pain scores improved from 5.4 to 5.2, and the percentage of patients receiving rescue opioids decreased from 15.4 to 13.1.

CONCLUSION

We successfully achieved and sustained our goals of improving acetaminophen use for our surgical patients without worsening pain scores or worsening use of intravenous opioids. Future directions include further refining our strategies and exploring additional opportunities to optimize pain management in pediatric perioperative settings.

Perioperative Pain Management for Thoracic Surgery: A Multi-Layered Approach

Cardiothoracic surgeries frequently pose unique challenges in the management of perioperative acute pain that require a multifaceted and personalized approach in order to optimize patient outcomes. This article discusses various analgesic strategies including regional anesthesia techniques such as thoracic epidurals, erector spinae plane blocks, and serratus anterior plane blocks and underscores the significance of perioperative multimodal medications, while providing nuanced recommendations for their use. This article further attempts to provide evidence for the efficacy of the different modalities and compares the effectiveness of the choice of analgesia. The roles of Acute Pain Services (APS) and Transitional Pain Services (TPS) in mitigating opioid dependence and chronic postsurgical pain are also discussed. Precision medicine is also presented as a potential way to offer a patient tailored analgesic strategy. Supported by various randomized controlled trials and meta-analyses, the article concludes that an integrated, patient-specific approach encompassing regional anesthesia and multimodal medications, while also utilizing the services of the Acute Pain Service can help to enhance pain management outcomes in cardiothoracic surgery.

Single Dose Intravenous Paracetamol versus Placebo in Postorthognathic Surgery Pain: A Randomized Clinical Trial

Background

The postorthognathic surgery patients experienced moderate to severe pain and could be at risk for opioid-related side effects. The aim of this study was to evaluate the efficacy of a single dose of intravenous paracetamol to control postorthognathic surgery pain and reduce opioid consumption.

Methods

The patients were randomized into two groups. The study group received intravenous paracetamol and the control group received a placebo immediately postoperation. The visual analogue pain scale (VAS) at 1-, 4-, 8-, 12-, 16-, 20-, and 24 -h postoperatively, morphine consumption, side effects from morphine, and patient satisfaction were analyzed.

Results

Sixty-two patients (thirty-one patients in each group) were included. The postoperative VAS in the study group was significantly lower than those in the control group (p value <0.001) at all time points. The total postoperative morphine consumption in the study group (45.1 ± 21.2 mcg/kg) was significantly lower compared with the control group (136.5 ± 49.9 mcg/kg) (p value <0.001). Patient satisfaction was significantly higher in the study group (4.7 ± 0.5 out of 5 points) than in the control group (4.1 ± 0.7 out of 5 points) (p value <0.001). The incidence of nausea and vomiting was significantly lower in the study group compared with the control group (p value <0.001 and 0.002, respectively).

Conclusion

A single dose of intravenous paracetamol as part of multimodal analgesia was effective for postorthognathic surgery pain. It provided significant benefits to patients, including reduced pain scores, decreased opioid consumption, reduced nausea and vomiting, and improved satisfaction. This trial is registered with TCTR20210908002.

Pharmacological induction of AMFR increases functional EAAT2 oligomer levels and reduces epileptic seizures in mice

Dysregulation of excitatory amino acid transporter 2 (EAAT2) contributes to the development of temporal lobe epilepsy (TLE). Several strategies for increasing total EAAT2 levels have been proposed. However, the mechanism underlying the oligomeric assembly of EAAT2, impairment of which inhibits the formation of functional oligomers by EAAT2 monomers, is still poorly understood. In the present study, we identified E3 ubiquitin ligase AMFR as an EAAT2-interacting protein. AMFR specifically increased the level of EAAT2 oligomers rather than inducing protein degradation through K542-specific ubiquitination. By using tissues from humans with TLE and epilepsy model mice, we observed that AMFR and EAAT2 oligomer levels were simultaneously decreased in the hippocampus. Screening of 2386 FDA-approved drugs revealed that the most common analgesic/antipyretic medicine, acetaminophen (APAP), can induce AMFR transcriptional activation via transcription factor SP1. Administration of APAP protected against pentylenetetrazol-induced epileptogenesis. In mice with chronic epilepsy, APAP treatment partially reduced the occurrence of spontaneous seizures and greatly enhanced the antiepileptic effects of 17AAG, an Hsp90 inhibitor that upregulates total EAAT2 levels, when the 2 compounds were administered together. In summary, our studies reveal an essential role for AMFR in regulating the oligomeric state of EAAT2 and suggest that APAP can improve the efficacy of EAAT2-targeted antiepileptic treatments.

Nonopioid analgesics for analgesia in critically ill patients: Friends, enemies, or collaborators

Patients in intensive care units (ICUs) experience pain, which they describe as a significant cause of stress during treatment. It can progress to chronic pain and significantly affect the quality of life. Opioids have long been the backbone of ICU pain therapy. The consequences of their long-term use are known today, such as prolonged ICU stay and mechanical ventilation, resulting in increased treatment costs. Additionally, abstinence syndrome is a consequence of abrupt opioid withdrawal. Also, there is a risk of tolerance and hyperalgesia after prolonged opioid use. Globally, opioid dependence after hospital opioid treatment is alarming, although there is still a lack of data on its incidence after ICU. Multimodal analgesia enables comfort to the patient, opioid-sparing, and avoidance of side effects of non-opioid analgesics. Nonsteroidal anti-inflammatory drugs (NSAIDs) are a broad group of drugs recommended with paracetamol to treat mild to moderate acute postoperative pain. Although often prescribed by intensivists, their use in treating painful conditions in ICU is controversial due to the possible consequences on the organs of critically ill patients. Due to the inhibition of cyclooxygenases, NSAIDs indirectly cause vasoconstriction of the renal arteries and arterioles, leading to kidney damage. NSAIDs inhibit platelet aggregation and may predispose to bleeding. Analgesia of a critically ill patient is a important part of their treatment, however it can be challenging in certain patients. Numerous combinations of pharmacological and non-pharmacological approaches can be adapted to the patient's current characteristics.

Perioperative Pain Management in Bariatric Anesthesia

Weight loss (bariatric) surgery is the most commonly performed elective surgical procedure in patients with morbid obesity. In this review, we provide an evidence-based update on perioperative pain management in bariatric anesthesia. We mention some newer preoperative aspects—medical optimization, physical preparation, patient education, and psychosocial factors—that can all improve pain management. In the intraoperative period, with bariatric surgery being almost universally performed laparoscopically, we emphasize the use of non-opioid adjuvant infusions (ketamine, lidocaine, and dexmedetomidine) and suggest some novel regional anesthesia techniques to reduce pain, opioid requirements, and side effects. We discuss some postoperative strategies that additionally focus on patient safety and identify patients at risk of persistent pain and opioid use after bariatric surgery. This review suggests that the use of a structured, step-wise, severity-based, opioid-sparing multimodal analgesic protocol within an enhanced recovery after surgery (ERAS) framework can improve postoperative pain management. Overall, by incorporating all these aspects throughout the perioperative journey ensures improved patient safety and outcomes from pain management in bariatric anesthesia.

Postoperative Pain Management in Enhanced Recovery Pathways

Postoperative pain is a common but often inadequately treated condition. Enhanced recovery pathways (ERPs) are increasingly being utilized to standardize perioperative care and improve outcomes. ERPs employ multimodal postoperative pain management strategies that minimize opioid use and promote recovery. While traditional opioid medications continue to play an important role in the treatment of postoperative pain, ERPs also rely on a wide range of non-opioid pharmacologic therapies as well as regional anesthesia techniques to manage pain in the postoperative setting. The evidence for the use of these interventions continues to evolve rapidly given the increasing focus on enhanced postoperative recovery. This article reviews the current evidence and knowledge gaps pertaining to commonly utilized modalities for postoperative pain management in ERPs.

A Dive Into Oliceridine and Its Novel Mechanism of Action

The current state of the opioid epidemic has revealed the need of utilizing proper pain management, especially in the postoperative setting where there is overuse of potent analgesics. However, the adequate treatment of pain is necessary to reduce mortality and cost of burden while increasing recovery and improving quality of life. Treatment of pain can be difficult to standardize as the guidelines from the American Pain Society discuss the importance of tailoring treatment options based on a patient’s sensitivities and risk factors. An effective fast-acting analgesic with adequate potency and few adverse events is the key to alleviating acute pain. Oliceridine (Olinvyk^®, Trevena Inc., Chesterbrook, USA) is a novel G protein-biased μ-opioid receptor agonist designed to decrease opioid-related adverse events (ORAEs) compared to conventional opioids. This article discusses oliceridine’s novel mechanism of action and current place in therapy. After a literature search on clinicaltrials.gov, three clinical trials were analyzed to understand the safety and efficacy of oliceridine. These trials demonstrated a comparable efficacy to morphine with a decreased risk for serious adverse events. However, further studies need to be conducted to evaluate the true safety impact of oliceridine compared to conventional opioids. 

Systematic Review of Systemic and Neuraxial Effects of Acetaminophen in Preclinical Models of Nociceptive Processing

Acetaminophen (APAP) in humans has robust effects with a high therapeutic index in altering postoperative and inflammatory pain states in clinical and experimental pain paradigms with no known abuse potential. This review considers the literature reflecting the preclinical actions of acetaminophen in a variety of pain models. Significant observations arising from this review are as follows: 1) acetaminophen has little effect upon acute nociceptive thresholds; 2) acetaminophen robustly reduces facilitated states as generated by mechanical and thermal hyperalgesic end points in mouse and rat models of carrageenan and complete Freund’s adjuvant evoked inflammation; 3) an antihyperalgesic effect is observed in models of facilitated processing with minimal inflammation (eg, phase II intraplantar formalin); and 4) potent anti-hyperpathic effects on the thermal hyperalgesia, mechanical and cold allodynia, allodynic thresholds in rat and mouse models of polyneuropathy and mononeuropathies and bone cancer pain. These results reflect a surprisingly robust drug effect upon a variety of facilitated states that clearly translate into a wide range of efficacy in preclinical models and to important end points in human therapy. The specific systems upon which acetaminophen may act based on targeted delivery suggest both a spinal and a supraspinal action. Review of current targets for this molecule excludes a role of cyclooxygenase inhibitor but includes effects that may be mediated through metabolites acting on the TRPV1 channel, or by effect upon cannabinoid and serotonin signaling. These findings suggest that the mode of action of acetaminophen, a drug with a long therapeutic history of utilization, has surprisingly robust effects on a variety of pain states in clinical patients and in preclinical models with a good therapeutic index, but in spite of its extensive use, its mechanisms of action are yet poorly understood.

Post-thoracotomy analgesia

Thoracotomy is considered one of the most painful operative procedures. Due to anatomical complexity, post-thoracotomy pain requires multimodal perioperative treatment to adequately manage to ensure proper postoperative recovery. There are several different strategies to control post-thoracotomy pain including interventional techniques, such as neuraxial and regional injections, and conservative treatments including medications, massage therapy, respiratory therapy, and physical therapy. This article describes different strategies and evidence base for their use.

Opioid use, misuse, and abuse: a narrative review about interventions to reduce opioid consumption and related adverse events in the perioperative setting

Opioids remain the most potent and predictable drug available for perioperative analgesia and moderate-to-severe cancer-related pain. However, their efficacy has been questioned in other clinical settings. Moreover, opioids are associated with a wide variety of dose-dependent adverse events, limiting their use. The indiscriminate prescription of opioids has fueled the so-called "opioid epidemic" in the United States and other developed countries. Thus, there has been a significant effort to develop strategies to curtail their unnecessary prescription. Here, we summarize the history, current trends, and new directions in perioperative opioid prescription in an unbiased manner.

Paracetamol: A Review of Guideline Recommendations

Musculoskeletal pain conditions are age-related, leading contributors to chronic pain and pain-related disability, which are expected to rise with the rapid global population aging. Current medical treatments provide only partial relief. Furthermore, non-steroidal anti-inflammatory drugs (NSAIDs) and opioids are effective in young and otherwise healthy individuals but are often contraindicated in elderly and frail patients. As a result of its favorable safety and tolerability record, paracetamol has long been the most common drug for treating pain. Strikingly, recent reports questioned its therapeutic value and safety. This review aims to present guideline recommendations. Paracetamol has been assessed in different conditions and demonstrated therapeutic efficacy on both acute and chronic pain. It is active as a single agent and is additive or synergistic with NSAIDs and opioids, improving their efficacy and safety. However, a lack of significant efficacy and hepatic toxicity have also been reported. Fast dissolving formulations of paracetamol provide superior and more extended pain relief that is similar to intravenous paracetamol. A dose reduction is recommended in patients with liver disease or malnourished. Genotyping may improve efficacy and safety. Within the current trend toward the minimization of opioid analgesia, it is consistently included in multimodal, non-opioid, or opioid-sparing therapies. Paracetamol is being recommended by guidelines as a first or second-line drug for acute pain and chronic pain, especially for patients with limited therapeutic options and for the elderly.

Reduction in Opiate Use, Pain, Nausea, and Length of Stay After Implementation of a Bariatric Enhanced Recovery After Surgery Protocol

PURPOSE

Evaluate adherence to bariatric surgery enhanced recovery after surgery (ERAS) protocols in pre-operative, operative, and post-operative phases, and to compare opiate use, nausea control, and length of stay (LOS) versus historical controls.

MATERIALS AND METHODS

A retrospective, observational cohort study was conducted to evaluate adherence to ERAS protocols and compare opiate and antiemetic use, pain intensity, and LOS versus those of traditional care (TC) patients preceding protocol implementation at Erie County Medical Center, a community-based hospital in Buffalo, NY, USA.

RESULTS

One hundred ERAS and TC patients were compared. Patients were similar in age (42.5 years), gender (female, ~ 80%), race (~ 80 white), and BMI (47 kg/m²). The primary procedure performed was sleeve gastrectomy (89% ERAS, 86% TC). Protocol adherence was high for ERAS phases: prior to admission (85-98%), pre-operative (96-100%), operative (93-99%), post-anesthesia care unit (PACU) (55-61%), and floor (86-98%). Opiate morphine milligram equivalent (MME) was reduced in ERAS vs. TC in hospital by 73% (43.5 ± 42.4 vs. 160 ± 116; p < 0.001), discharge prescribing by 53% (34.8 ± 38.2 vs. 74 ± 125 MME; p = 0.003), and in total by 69% (78.3 ± 67.5 vs. 252 ± 160; p < 0.001). Despite lower opiate use, ERAS had lower pain intensity entering PACU (1.1 ± 1.8 vs. 1.9 ± 2.6; p < 0.011), leaving PACU (1.7 ± 1.5 vs. 2.9 ± 1.5; p < 0.001), and floor day 0 (5.0 ± 2.1 vs. 5.9 ± 1.8; p < 0.001). Fewer ERAS required antiemetic day 0 (63% vs. 94%; p < 0.001). ERAS were discharged in fewer hours than TC (41.1 ± 15.5 vs. 52.1 ± 18.9 h; p < 0.001).

CONCLUSIONS

Bariatric surgery ERAS protocols were implemented with a high rate of adherence and yielded profound reduction in operative and post-operative opiate use while improving pain control and nausea management in hospital and decreasing LOS.

Scheduled Prophylactic 6-Hourly IV AcetaminopheN to Prevent Postoperative Delirium in Older CaRdiac SurgicAl Patients (PANDORA): protocol for a multicentre randomised controlled trial

INTRODUCTION

Postoperative delirium is common among older cardiac surgery patients. Often difficult to predict and address prophylactically, delirium complicates the postoperative course by increasing morbidity and mortality as well as prolonging both hospital and intensive care unit (ICU) lengths of stay. Based on our pilot trial, we intend to study the effect of scheduled 6-hourly acetaminophen administration for 48 hours post-cardiac surgery with cardiopulmonary bypass (CPB) on the incidence of in-hospital delirium and long-term neurocognitive outcomes. Additionally, effect on duration and severity of delirium, rescue analgesic consumption, acute and chronic pain scores and lengths of hospital and ICU stay will also be explored.

METHODS AND ANALYSIS

This multicentre, randomised, placebo-controlled, quadruple-blinded trial will include 900 older (>60 years) cardiac surgical patients requiring CPB. Patients meeting the inclusion criteria and not meeting any exclusion criteria will be enrolled at seven centres across the USA with Beth Israel Deaconess Medical Center (BIDMC), Boston, as the central coordinating centre. Additional sites may be included to broaden or speed accrual. The primary outcome measure is the incidence of in-hospital delirium till day 30. Secondary outcomes include the duration and severity of in-hospital delirium, hospital and ICU lengths of stay, postoperative pain scores, postoperative rescue analgesic consumption, postoperative cognitive function and chronic sternal pain. Creation of a biorepository and the use of intraoperative-blinded electroencephalogram (EEG) and cerebral oximetry data will support exploratory endpoints to determine mechanistic predictors of postoperative delirium.

ETHICS AND DISSEMINATION

This trial is approved and centrally facilitated by the Institutional Review Board at BIDMC. An independent Data Safety and Monitoring Board is responsible for maintaining safety oversight. Protocol # 2019 P00075, V.1.4 (dated 20 October 2020).

TRIAL REGISTRATION NUMBER

NCT04093219.

Challenges of Combining Opioids and P2Y12 Inhibitors in Acute Coronary Syndrome: Should the Future Be Opioid Free?

Morphine has been long recognized as standard of care in the treatment of acute coronary syndrome (ACS) patients; however, its safety has recently been called into question due to a drug interaction with P2Y₁₂ inhibitors. Opioids, given in combination with P2Y₁₂ inhibitors, can reduce antiplatelet effects by slowing gastrointestinal motility and ultimately reducing drug absorption. While there are proposed benefits of opioids in ACS patients, conflicting data regarding clinical outcomes exist. The majority of clinical data slightly favors opioid use in ST-elevation myocardial infarction over non-ST-elevation myocardial infarction, although trends for increased myocardial infarction are present in both settings. Current practice should be aimed at discerning the need for routine opioid use in ACS. Alternative strategies may be needed to overcome these interactions; however, no robust data are currently available to support these treatment options. Future research should be aimed at non-opioid treatment options in ACS, as opioid use remains controversial in this population.

Effect of preoperative intravenous vs oral acetaminophen on postoperative opioid consumption in an enhanced recovery after surgery (ERAS) program in patients undergoing open gynecologic oncology surgery

OBJECTIVE

Both intravenous (IV) and oral acetaminophen provide effective opioid-sparing analgesia after surgery when used as part of a multimodal preemptive pain management strategy. The purpose of this study was to compare postoperative opioid consumption in patients undergoing open gynecologic oncology surgery who received preoperative IV vs oral acetaminophen within an enhanced recovery after surgery (ERAS) program.

METHODS

Retrospective data were collected on consecutive patients undergoing open gynecologic oncology surgery from May 1, 2016 to February 28, 2018 in patients receiving either 1 g IV or oral acetaminophen preoperatively. Patients were given a preoperative multimodal analgesia regimen including acetaminophen, celecoxib, pregabalin and tramadol. The primary outcomes were morphine equivalent daily doses (MEDD) on postoperative days (POD) 0 and 1. Secondary outcomes included highest patient-reported pain score in the post-anesthesia care unit (PACU) and intraoperative MEDD. Regression models adjusted by matched pairs were fit to estimate the average treatment effect of IV vs oral acetaminophen on MEDD.

RESULTS

Of 353 patients, 178 (50.4%) received IV acetaminophen and 175 (49.6%) received oral acetaminophen. When balancing across the matched samples, there was no difference in postoperative MEDD for POD 0 between the IV and oral acetaminophen groups (Beta = -1.11; 95% CI: -4.83 to 2.60; p = 0.56). On POD 1, there was no difference between the IV and oral groups (Beta = 2.24; 95% CI: -2.76 to 7.25; p = 0.38).

CONCLUSIONS

There was no difference in postoperative opioid consumption between patients receiving preoperative IV or oral acetaminophen within an ERAS program for patients undergoing open gynecologic oncology surgery.

An Opioid-Sparing Protocol Improves Recovery Time and Reduces Opioid Use After Laparoscopic Sleeve Gastrectomy

PURPOSE

The current literature is sparse on post discharge pain management for bariatric surgical patients. This study aimed to determine if an opioid-sparing protocol could decrease opioid use during the postoperative period (hospital to home).

MATERIALS AND METHODS

In this retrospective cohort study, we implemented an opioid-sparing protocol in January 2018, for patients undergoing laparoscopic sleeve gastrectomy (LSG) at our institution. We compared recovery time, pain scores (in hospital and at home), and perioperative opioid use between the historic control group (February 2017 to December 2017) and the opioid-sparing group (January 2018 to December 2018). A p value of < .05 was considered statistically significant.

RESULTS

The study included 400 patients (200 in each group), and 165 participated in the phone survey. Baseline characteristics were similar, except the control group had a higher body mass index and body weight. The average recovery time was significantly shorter in the opioid-sparing group (18.9 versus 35.3 days, P = .043). There was no significant difference in mean postoperative pain scores in the hospital or at home. The opioid-sparing group required significantly fewer opioids postoperatively (10.4 versus 16.1 morphine milligram equivalents, P < .001). Only 1 out of the 200 patients in the opioid-sparing arm requested an opioid prescription after discharge.

CONCLUSION

Implementation of an opioid-sparing protocol improved recovery time and reduced postoperative opioid use in the hospital and after discharge without changing perceived pain in patients undergoing LSG.

Maximization of Non-Opioid Multimodal Analgesia in Ambulatory Surgery Centers

Ambulatory surgery centers aid the healthcare system by not only providing a cost-effective option for delivery of care but also by helping to reduce overwhelming case volumes at inpatient facilities. While outpatient protocols have been designed for an increasing number of surgical procedures, the inpatient to outpatient transition of surgery remains limited by both procedure type and patient comorbidities. This limitation stems in part from the heavy emphasis on accelerated discharge following outpatient procedures, given that prolonged recovery time is associated with delayed turnover and increased nursing care demands. Since its inception, enhanced recovery after surgery (ERAS) has aimed to primarily reduce the disruption of physiologic homeostasis that occurs secondary to surgery. More recently, the aim of ERAS has evolved to help transition inpatient procedures to outpatient settings and may even be useful in more emergent cases. It should be noted, however, that outpatient surgery even in combination with ERAS is not the best option for all patients, and the use of ERAS protocols should be complemented with predictive assessments of patient risk. Beyond augmenting the efficiency of outpatient surgery, ERAS protocols, when used in eligible patients and especially when combined with regional anesthetic techniques, are effective in delivering opioid-sparing pain management while increasing overall outcomes and patient satisfaction rates.

Optimizing Perioperative Use of Opioids: A Multimodal Approach

Purpose of Review

The main purpose of this article is to review recent literature regarding multimodal analgesia medications, citing their recommended doses, efficacy, and side effects. The second part of this report will provide a description of drugs in different stages of development which have novel mechanisms with less side effects such as tolerance and addiction.

Recent Findings

Multimodal analgesia is a technique that facilitates perioperative pain management by employing two or more systemic analgesics along with regional anesthesia, when possible. Even though opioids and non-opioid analgesics remain the most common medication used for acute pain management after surgery, they have many undesirable side effects including the potential for misuse. Newer analgesics including peripheral acting opioids, nitric oxide inhibitors, calcitonin gene-related peptide receptor antagonists, interleukin-6 receptor antagonists and gene therapy are under intensive investigation.

Summary

A patient's first exposure to opioids is often in the perioperative setting, a vulnerable time when multimodal therapy can play a large role in decreasing opioid exposure. Additionally, the current shift towards faster recovery times, fewer post-operative complications and improved cost-effectiveness during the perioperative period has made multimodal analgesia a central pillar of Enhanced Recovery After Surgery (ERAS) protocols.

A Practical Approach to Acute Postoperative Pain Management in Chronic Pain Patients

In the United States, more than 100 million people suffer from chronic pain. Among patients presenting for surgery, about one in four have chronic pain. Acute perioperative pain management in this population is challenging because many patients with chronic pain require long-term opioids for the management of this pain, which may result in tolerance, physical dependence, addiction, and opioid-induced hyperalgesia. These challenges are compounded by the ongoing opioid epidemic that has resulted in calls for a reduction in opioid use, with a concurrent increase in the number of patients with chronic opioid exposure presenting for surgery. This article aims to summarize practical considerations for acute postoperative pain management in patients with chronic pain conditions. A patient-centered acute pain management plan, including nonopioid analgesics, regional anesthesia, and careful selection of opioid medications, can lead to adequate analgesia and satisfaction with care. Also, a meticulous rotation from one opioid to another may decrease opioid requirement, increase analgesic effectiveness, and improve satisfaction with care.

A systematic review and trial sequential analysis of intravenous vs. oral peri-operative paracetamol

Postoperative pain might be different after intravenous vs. oral paracetamol. We systematically reviewed randomised controlled trials in patients >15 years that compared intravenous with oral paracetamol for postoperative pain. We identified 14 trials with 1695 participants. There was inconclusive evidence for an effect of route of paracetamol administration on postoperative pain at 0–2 h (734 participants), 2–6 h (766 participants), 6–24 h (1115 participants) and >24 h (248 participants), with differences in standardised mean (95%CI) pain scores for intravenous vs. oral of −0.17 (−0.45 to 0.10), −0.09 (−0.24 to 0.06), 0.06 (−0.12 to 0.23) and 0.03 (−0.22 to 0.28), respectively. Trial sequential analyses suggested that a total of 3948 participants would be needed to demonstrate a meaningful difference in pain or its absence at 0–2 h. There were no differences in secondary outcomes. Intravenous paracetamol is more expensive than oral paracetamol. Substitution of oral paracetamol in half the patients given intravenous paracetamol in our hospital would save around £ 38,711 (€ 43,960 or US$ 47,498) per annum.

Intravenous versus oral paracetamol in a UK ambulance service: a case control study

OBJECTIVES

To determine the effectiveness of intravenous versus oral paracetamol (acetaminophen) in the management of acute pain in the out-of-hospital setting.

METHODS

We extracted ambulance electronic patient care records for all patients who received 1 g intravenous paracetamol throughout January 2019, and case matched these by sex and age with consecutive patients who received 1 g oral paracetamol over the same time period. Eligible for inclusion were all patients aged ≥ 18 who received 1 g paracetamol for acute pain and who were transported to the emergency department (ED). The primary outcome was the mean reduction in pain score using the numeric rating scale (NRS), with a reduction of 2 or more accepted as clinically significant.

RESULTS

80 care records were eligible for analysis; 40 patients received intravenous and 40 patients received oral paracetamol. The mean age of both groups was 54 years (± 3 years) and 67.5% (n = 54) were female. Patients receiving intravenous paracetamol had a clinically significant mean (SD) improved pain score compared to those receiving oral paracetamol, 2.02 (1.64) versus 0.75 (1.76), respectively [p = 0.0013]. 13/40 (32.5%) patients who received intravenous paracetamol saw an improved pain score of ≥ 2 compared to 8/40 (20%) who received oral paracetamol. No patients received additional analgesia or reported any adverse symptoms. Abdominal pain, infection and trauma were the most common causes of pain in both groups.

CONCLUSION

Our study suggests that intravenous paracetamol is more effective than oral paracetamol when managing acute pain in the out-of-hospital setting. Our findings support further investigation of the role of paracetamol in paramedic practice using more robust methods.

Basics and Best Practices of Multimodal Pain Management for the Plastic Surgeon

Pain management is a central focus for the plastic surgeon’s perioperative planning, and it no longer represents a postoperative afterthought. Protocols that rely on opioid-only pain therapy are outdated and discouraged, as they do not achieve optimal pain relief, increase postoperative morbidity, and contribute to the growing opioid epidemic. A multimodal approach to pain management using non-opioid analgesic techniques is an integral component of enhanced recovery after surgery protocols. Careful perioperative planning for optimal pain management must be achieved in multidisciplinary collaboration with the perioperative care team including anesthesiology. This allows pain management interventions to occur at 3 critical opportunities—preoperative, intraoperative, and postoperative settings.

Intravenous Acetaminophen Versus Placebo in Post-bariatric Surgery Multimodal Pain Management: a Meta-analysis of Randomized Controlled Trials

BACKGROUND

Pain management after bariatric surgery is challenging. Recent trials have been exploring the role of intravenous (IV) acetaminophen in multimodal analgesic therapy. This systematic review and meta-analysis assessed the effect of IV acetaminophen compared to placebo for pain management after bariatric surgery.

METHODS

A comprehensive search of MEDLINE, Embase, CENTRAL, and PubMed databases were performed. Randomized controlled trials (RCTs) comparing IV acetaminophen to placebo as part of multimodal pain management after bariatric surgery in patients with obesity were included. Key outcomes were analyzed using random-effects meta-analysis, and the certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE).

RESULTS

Four RCTs including 349 patients met the inclusion criteria, of whom 175 were provided IV acetaminophen and 174 were provided placebo. Patients given IV acetaminophen demonstrated a lower postoperative pain score (mean difference (MD) - 0.66, 95% CI - 1.03 to - 0.28, P < 0.001) 24 h after surgery and lower postoperative opioid use (MD - 6.44, 95% CI - 9.26 to - 3.61, P < 0.001; I² = 0%) in morphine equivalent doses (MED) within 24 h compared with the placebo group. There was no significant difference in length of stay between groups (MD - 0.26, 95% CI - 0.55 to 0.03, P = 0.08).

CONCLUSIONS

The use of IV acetaminophen after bariatric surgery is effective in reducing pain score after 24 h and postoperative opioid doses, but not length of stay. Provided the benefits of IV acetaminophen, its addition to postoperative care and enhanced recovery programs may be warranted.

Perioperative pain management in elderly patients with а proximal femoral fracture: evidence review

The purpose of this article is to compare different methods of analgesia during perioperative period in elderly patients with а proximal femoral fracture. The incidence of hip fracture is high and also rises with the age, for example, In Great Britain, number of patients with a hip fracture will be approximately 100 000 in 2033, and it’s also associated with significant healthcare financing. Nevertheless, effective pain management is a big challenge for clinicians because of considerable problems in geriatric patients, including age, physiological changes in the elderly, preexisting comorbidities, cognitive impairment, high risk of delirium, problems with rehabilitation and probability of an independent life [12].   Opioids are still the main option for hip fracture pain management, despite differences in pharmacokinetics and pharmacodynamics in elderly patients, which are correlated with high frequency of side effects. Opioid-related adverse drug events are associated with worse patient outcomes such as morbidity, mortality and length of stay increase. Therefore, peripheral nerve blocks as part of multimodal analgesic technique can provide more effective pain control after hip fracture. Comprehensive literature searches focus on the use of peripheral nerves blocks as preoperative analgesia, as postoperative analgesia or as a supplement to general anesthesia for hip fracture surgery.

Intravenous Acetaminophen Reduces Length of Stay Via Mediation of Postoperative Opioid Consumption After Posterior Spinal Fusion in a Pediatric Cohort

OBJECTIVES

Since approval of intravenous acetaminophen (IV APAP), its use has become quite common without strong positive evidence. Our goal was to determine the effect of IV APAP on length of hospital stay (LOS) via mediation of opioid-related side effects in pediatric patients.

MATERIALS AND METHODS

After Institutional Review Board approval, 114 adolescents undergoing posterior spinal fusion were prospectively recruited and managed postoperatively with patient-controlled analgesia and adjuvant therapy. Patients were divided into 2 groups based on the use of IV APAP: control (n=70) and treatment (n=44). Association of IV APAP use with opioid outcomes was analyzed using inverse probability of treatment weighting (IPTW)-adjusted propensity scores to balance the 2 groups for all significant covariates except postoperative opioid consumption. Mediation analysis was carried out for LOS with IV APAP as the independent variable and morphine consumption as the mediator.

RESULTS

Oral intake was delayed by ∼1 day (P<0.001) and LOS was 0.6 days longer in the control group (P=0.044). After IPTW, time to oral intake remained significantly longer in the control group (P=0.014). The mediation model with IPTW revealed a significant negative association between IV APAP and morphine consumption (P<0.001), which significantly increased LOS (P<0.003). IV APAP had a significant opioid-sparing effect associated with shorter LOS.

DISCUSSION

IV APAP hastens oral intake and is associated with decreased LOS in an adolescent surgery population likely through decreased opioid consumption. Through addition of IV APAP in this population, LOS may be decreased, an important implication in the setting of escalating health care costs.

Multimodal Analgesia for Perioperative Management of Patients presenting for Spinal Surgery

Multimodal, non-opioid based analgesia has become the cornerstone of ERAS protocols for effective analgesia after spinal surgery. Opioid side effects, dependence and legislation restricting long term opioid use has led to a resurgence in interest in opioid sparing techniques. The increasing array of multimodal opioid sparing analgesics available for spinal surgery targeting novel receptors, transmitters, and altering epigenetics can help provide an optimal perioperative experience with less opioid side effects and long-term dependence. Epigenetic mechanisms of pain may enhance or suppress gene expression, without altering the genome itself. Such mechanisms are complex, dynamic and responsive to environment. Alterations that occur can affect the pathophysiology of pain management at a DNA level, modifying perceived pain relief. In this review, we provide a brief overview of epigenetics of pain, systemic local anesthetics and neuraxial techniques that continue to remain useful for spinal surgery, neuropathic agents, as well as other common and less common target receptors for a truly multimodal approach to perioperative pain management.

Intravenous Versus Oral Acetaminophen in Ambulatory Surgical Center Laparoscopic Cholecystectomies: A Retrospective Analysis

STUDY OBJECTIVE

The primary aim was to compare postoperative pain scores in patients undergoing laparoscopic cholecystectomy and receiving intravenous (IV) or oral (PO) acetaminophen (APAP) as part of a multimodal analgesic regimen to examine whether PO APAP is non-inferior to IV APAP.

DESIGN

Retrospective analysis.

SETTING

Ambulatory surgical center (ASC) in an academic setting.

PATIENTS

579 patients (18-70 years old), American Society of Anesthesiologists physical status I-III, undergoing laparoscopic cholecystectomy.

INTERVENTIONS

Patients received 1,000 mg IV APAP intraoperatively (n = 319) or 1,000 mg PO APAP preoperatively (n = 260).

MEASUREMENTS

The primary outcome was the median difference in post-anesthesia care unit (PACU) end-pain scores between the groups. Median pain scores were also compared on PACU admission, and at 15, 30, 45, and 60 minutes. Additional measures include PACU rescue-analgesia consumption, time to first PACU rescue analgesia, intraoperative use of opioid and nonopioid analgesics, PACU length of stay, and PACU rescue nausea and vomiting therapy.

MAIN RESULTS

In both groups, the PACU median end-pain score was 2. The 90% confidence interval (CI) for difference in median pain scores between groups was [0, 0]; the CI upper limit was below the non-inferior margin of 1 pain-score point, indicating PO APAP's non-inferiority to IV APAP. There were no statistically significant differences in the percentages of patients receiving PACU hydromorphone equivalents between the IV and PO groups (75% vs. 77%, P = 0.72) or in the mean dose received (0.5 mg vs. 0.5 mg, P = 0.66).

CONCLUSION

Single-dose PO APAP is non-inferior to IV APAP for postoperative analgesia in ASC laparoscopic cholecystectomy patients. The value of single-dose IV APAP in this population should be further explored.

Preemptive Oral Acetaminophen for Women Undergoing Total Laparoscopic Hysterectomy

OBJECTIVE

To decrease hospital expenses by administering oral acetaminophen rather than intravenous (IV) acetaminophen to women who undergo laparoscopic hysterectomy.

DESIGN

A quality improvement project using a between-groups, pre-/postimplementation design for women undergoing total laparoscopic hysterectomy. Retrospective chart review was used to compare data of women who received intraoperative IV acetaminophen before implementation versus women who received oral acetaminophen after implementation. Pain scores and opioid consumption in morphine equivalents were recorded at four time points.

SETTING/LOCAL PROBLEM

A 369-bed hospital in the southeastern United States, where, in 2016, nearly $260,000 was spent on perioperative IV acetaminophen for all operating room cases.

PARTICIPANTS

Women between the ages of 18 and 55 years scheduled to have total laparoscopic hysterectomy were included. Excluded were women with a history of chronic pain, opioid use, or liver pathology; women with a contraindication to nonsteroidal anti-inflammatory drugs; and women whose procedures were converted from laparoscopic to open.

INTERVENTION/MEASUREMENTS

Women were instructed to take oral acetaminophen the day before surgery in divided doses, with 1 g every 6 hours, for a total dose of 3 g. On the day of surgery, women received the final 1-g dose of oral acetaminophen.

RESULTS

There were no significant differences between groups for pain scores or total opioids received before implementation (mean = 3.28, standard deviation = 2.05) compared with after implementation (mean = 3.65, standard deviation = 1.63; t [18] = -.043, p = .674). The preimplementation cost per individual was $30.03 for 1 g of IV acetaminophen, and the postimplementation cost was $0.36 for 2 500-mg oral acetaminophen tablets, a 98.8% relative cost decrease per woman.

CONCLUSION

Replacing IV acetaminophen with preemptive oral acetaminophen has the potential to save money without compromising care.

Reduced length of stay and hospitalization costs among inpatient hysterectomy patients with postoperative pain management including IV versus oral acetaminophen

OBJECTIVE

To compare the outcomes of hysterectomy patients who received standard pain management including IV acetaminophen (IV APAP) versus oral APAP.

METHODS

We performed a retrospective analysis of the Premier Database (January 2012 to September 2015) comparing hysterectomy patients who received postoperative pain management including IV APAP to those who received oral APAP starting on the day of surgery and continuing up to the third post-operative day, with no exclusions based on additional pain management. We compared the groups on length of stay (LOS), hospitalization costs, and average daily morphine equivalent dose (MED). The quarterly rate of IV APAP use for all hospitalizations by hospital was used as an instrumental variable in two-stage least squares regressions also adjusting for patient demographics, clinical risk factors, and hospital characteristics.

RESULTS

We identified 22,828 hysterectomy patients including 14,811 (65%) who had received IV APAP. Study subjects averaged 50 and 52 years of age, respectively in the IV APAP and oral APAP cohorts and were predominantly non-Hispanic Caucasians (≥60% in both cohorts). Instrumental variable models found IV APAP associated with 0.8 days shorter hospitalization (95% CI: -0.92 to -0.68, p<0.0001) and $2,449 lower hospitalization costs (95% CI: -$2,902 to -$1,996, p<0.0001). Average daily MED trended lower without statistical significance (-1.41 mg, 95% CI: -3.43 mg to 0.61 mg, p = 0.17).

CONCLUSIONS

Compared to oral APAP, managing post-hysterectomy pain with IV APAP is associated with shorter LOS and lower total hospitalization costs.

Designing the ideal perioperative pain management plan starts with multimodal analgesia

Multimodal analgesia is defined as the use of more than one pharmacological class of analgesic medication targeting different receptors along the pain pathway with the goal of improving analgesia while reducing individual class-related side effects. Evidence today supports the routine use of multimodal analgesia in the perioperative period to eliminate the over-reliance on opioids for pain control and to reduce opioid-related adverse events. A multimodal analgesic protocol should be surgery-specific, functioning more like a checklist than a recipe, with options to tailor to the individual patient. Elements of this protocol may include opioids, non-opioid systemic analgesics like acetaminophen, non-steroidal anti-inflammatory drugs, gabapentinoids, ketamine, and local anesthetics administered by infiltration, regional block, or the intravenous route. While implementation of multimodal analgesic protocols perioperatively is recommended as an intervention to decrease the prevalence of long-term opioid use following surgery, the concurrent crisis of drug shortages presents an additional challenge. Anesthesiologists and acute pain medicine specialists will need to advocate locally and nationally to ensure a steady supply of analgesic medications and in-class alternatives for their patients’ perioperative pain management.

The rising tide of opioid use and abuse: the role of the anesthesiologist

Opioid use has risen dramatically in the past three decades. In the USA, opioid overdose has become a leading cause of unintentional death, surpassing motor vehicle accidents. A patient's first exposure to opioids may be during the perioperative period, a time where anesthesiologists have a significant role in pain management. Almost all patients in the USA receive opioids during a surgical encounter. Opioids have many undesirable side effects, including potential for misuse, or opioid use disorder. Anesthesiologists and surgeons employ several methods to decrease unnecessary opioid use, opioid-related adverse events, and side effects in the perioperative period. Multimodal analgesia, enhanced recovery pathways, and regional anesthesia are key tools as we work towards optimal opioid stewardship and the ideal of effective analgesia without undesirable sequelae.

Pharmacokinetics of Oral and Intravenous Paracetamol (Acetaminophen) When Co-Administered with Intravenous Morphine in Healthy Adult Subjects

BACKGROUND AND OBJECTIVE

Several features favor paracetamol (acetaminophen) administration by the intravenous rather than the oral route in the postoperative setting. This study compared the pharmacokinetics and bioavailability of oral and intravenous paracetamol when given with or without an opioid, morphine.

METHODS

In this randomized, single-blind, parallel, repeat-dose study in healthy adults, subjects received four repeat doses of oral or intravenous 1000 mg paracetamol at 6-h intervals, and morphine infusions (0.125 mg/kg) at the 2nd and 3rd intervals. Comparisons of plasma pharmacokinetic profiles were conducted before, during, and after opioid co-administrations.

RESULTS

Twenty-two subjects were included in the pharmacokinetic analysis. Observed paracetamol peak concentration (C max) and area under the plasma concentration-time curve over the dosing interval (AUC0-6) were reduced when oral paracetamol was co-administered with morphine (reduced from 11.6 to 7.25 µg/mL and from 31.00 to 25.51 µg·h/mL, respectively), followed by an abruptly increased C max and AUC0-6 upon discontinuation of morphine (to 13.5 µg/mL and 52.38 µg·h/mL, respectively). There was also a significantly prolonged mean time to peak plasma concentration (T max) after the 4th dose of oral paracetamol (2.84 h) compared to the 1st dose (1.48 h). However, pharmacokinetic parameters of paracetamol were not impacted when intravenous paracetamol was co-administered with morphine.

CONCLUSIONS

Morphine co-administration significantly impacted the pharmacokinetics of oral but not intravenous paracetamol. The abrupt release of accumulated paracetamol at the end of morphine-mediated gastrointestinal inhibition following oral but not intravenous administration of paracetamol suggests that intravenous paracetamol provides a better option for the management of postoperative pain. CLINICALTRIALS.

GOV IDENTIFIER

NCT02848729.

Cost-effectiveness of intravenous acetaminophen and ketorolac in adolescents undergoing idiopathic scoliosis surgery

BACKGROUND

Enhanced recovery after surgery protocols increasingly use multimodal analgesia after major surgeries with intravenous acetaminophen and ketorolac, despite no documented cost-effectiveness of these strategies.

AIMS

The goal of this prospective cohort study was to model cost-effectiveness of adding acetaminophen or acetaminophen + ketorolac to opioids for postoperative outcomes in children having scoliosis surgery.

METHODS

Of 106 postsurgical children, 36 received only opioids, 26 received intravenous acetaminophen, and 44 received acetaminophen + ketorolac as analgesia adjuncts. Costs were calculated in 2015 US $. Decision analytic model was constructed with Decision Maker^® software. Base-case and sensitivity analyses were performed with effectiveness defined as avoidance of opioid adverse effects.

RESULTS

The groups were comparable demographically. Compared with opioids-only strategy, subjects in the intravenous acetaminophen + ketorolac strategy consumed less opioids (P = .002; difference in mean morphine consumption on postoperative days 1 and 2 was -0.44 mg/kg (95% CI -0.72 to -0.16); tolerated meals earlier (P < .001; RR 0.250 (0.112-0.556)) and had less constipation (P < .001; RR 0.226 (0.094-0.546)). Base-case analysis showed that of the 3 strategies, use of opioids alone is both most costly and least effective, opioids + intravenous acetaminophen is intermediate in both cost and effectiveness; and opioids + intravenous acetaminophen and ketorolac is the least expensive and most effective strategy. The addition of intravenous acetaminophen with or without ketorolac to an opioid-only strategy saves $510-$947 per patient undergoing spine surgery and decreases opioid side effects.

CONCLUSION

Intravenous acetaminophen with or without ketorolac reduced opioid consumption, opioid-related adverse effects, length of stay, and thereby cost of care following idiopathic scoliosis in adolescents compared with opioids-alone postoperative analgesia strategy.

Perioperative pain management strategies among women having reproductive surgeries

This review presents opioid-sparing strategies for perioperative pain management among women undergoing reproductive surgeries and procedures. Recommendations are provided regarding the use of nonsteroidal anti-inflammatory drugs, acetaminophen, other adjunctive medications, and regional anesthetic blocks. Additional considerations for chronic opioid users or patients using opioid replacement or antagonist therapy are discussed.

American Society for Enhanced Recovery (ASER) and Perioperative Quality Initiative (POQI) joint consensus statement on optimal analgesia within an enhanced recovery pathway for colorectal surgery: part 1-from the preoperative period to PACU

Background

Within an enhanced recovery pathway (ERP), the approach to treating pain should be multifaceted and the goal should be to deliver “optimal analgesia,” which we define in this paper as a technique that optimizes patient comfort and facilitates functional recovery with the fewest medication side effects.

Methods

With input from a multi-disciplinary, international group of clinicians, and through a structured review of the literature and use of a modified Delphi method, we achieved consensus surrounding the topic of optimal analgesia in the perioperative period for colorectal surgery patients.

Discussion

As a part of the first Perioperative Quality Improvement (POQI) workgroup meeting, we sought to develop a consensus document describing a comprehensive, yet rational and practical, approach for developing an evidence-based plan for achieving optimal analgesia, specifically for a colorectal surgery ERP. The goal was two-fold: (a) that application of this process would lead to improved patient outcomes and (b) that investigation of the questions raised would identify knowledge gaps to aid the direction for research into analgesia within ERPs in the years to come. This document details the evidence for a wide range of analgesic components, with particular focus from the preoperative period to the post-anesthesia care unit. The overall conclusion is that the combination of analgesic techniques employed in the perioperative period is not important as long as it is effective in delivering the goal of optimal analgesia as set forth in this document.

American Society for Enhanced Recovery (ASER) and Perioperative Quality Initiative (POQI) Joint Consensus Statement on Optimal Analgesia within an Enhanced Recovery Pathway for Colorectal Surgery: Part 2-From PACU to the Transition Home

BACKGROUND

Within an enhanced recovery pathway (ERP), the approach to treating pain should be multifaceted and the goal should be to deliver "optimal analgesia", which we define in this paper as a technique that optimizes patient comfort and facilitates functional recovery with the fewest medication side effects.

METHODS

With input from a multidisciplinary, international group of experts and through a structured review of the literature and use of a modified Delphi method, we achieved consensus surrounding the topic of optimal analgesia in the perioperative period for colorectal surgery patients.

DISCUSSION

As a part of the first Perioperative Quality Improvement (POQI) workgroup meeting, we sought to develop a consensus document describing a comprehensive, yet rational and practical, approach for developing an evidence-based plan for achieving optimal analgesia, specifically for a colorectal surgery within an ERP. The goal was twofold: (a) that application of this process would lead to improved patient outcomes and (b) that investigation of the questions raised would identify knowledge gaps to aid the direction for research into analgesia within ERPs in the years to come. This document details the evidence for a wide range of analgesic components, with particular focus on care in the post-anesthesia care unit, general care ward, and transition to home after discharge. The preoperative and operative consensus statement for analgesia was covered in Part 1 of this paper. The overall conclusion is that the combination of analgesic techniques employed in the perioperative period is not important as long as it is effective in delivering the goal of "optimal analgesia" as set forth in this document.

Multimodal Analgesia, Current Concepts, and Acute Pain Considerations

PURPOSE OF REVIEW

Management of acute pain following surgery using a multimodal approach is recommended by the American Society of Anesthesiologists whenever possible. In addition to opioids, drugs with differing mechanisms of actions target pain pathways resulting in additive and/or synergistic effects. Some of these agents include alpha 2 agonists, NMDA receptor antagonists, gabapentinoids, dexamethasone, NSAIDs, acetaminophen, and duloxetine.

RECENT FINDINGS

Alpha 2 agonists have been shown to have opioid-sparing effects, but can cause hypotension and bradycardia and must be taken into consideration when administered. Acetaminophen is commonly used in a multimodal approach, with recent evidence lacking for the use of IV over oral formulations in patients able to take medications by mouth. Studies involving gabapentinoids have been mixed with some showing benefit; however, future large randomized controlled trials are needed. Ketamine is known to have powerful analgesic effects and, when combined with magnesium and other agents, may have a synergistic effect. Dexamethasone reduces postoperative nausea and vomiting and has been demonstrated to be an effective adjunct in multimodal analgesia. The serotonin-norepinephrine reuptake inhibitor, duloxetine, is a novel agent, but studies are limited and further evidence is needed. Overall, a multimodal analgesic approach should be used when treating postoperative pain, as it can potentially reduce side effects and provide the benefit of treating pain through different cellular pathways.