The Effect of Preoperative Gabapentin on Postoperative Nausea and Vomiting: A Meta-Analysis

Postoperative Multimodal Analgesia Strategy for Enhanced Recovery After Surgery in Elderly Colorectal Cancer Patients

Enhanced Recovery After Surgery (ERAS) protocols have substantially proven their merit in diminishing recuperation durations and mitigating postoperative adverse events in geriatric populations undergoing colorectal cancer procedures. Despite this, the pivotal aspect of postoperative pain control has not garnered the commensurate attention it deserves. Typically, employing a multimodal analgesia regimen that weaves together nonsteroidal anti-inflammatory drugs, opioids, local anesthetics, and nerve blocks stands paramount in curtailing surgical complications and facilitating reduced convalescence within hospital confines. Nevertheless, this integrative pain strategy is not devoid of pitfalls; the specter of organ dysfunction looms over the geriatric cohort, rooted in the abuse of analgesics or the complex interplay of polypharmacy. Revolutionary research is delving into alternative delivery and release modalities, seeking to allay the inadvertent consequences of analgesia and thereby potentially elevating postoperative outcomes for the elderly post-colorectal cancer surgery populace. This review examines the dual aspects of multimodal analgesia regimens by comparing their established benefits with potential limitations and offers insight into the evolving strategies of drug administration and release.

Nausea and Vomiting After Posterior Spinal Fusion in Adolescent Idiopathic Scoliosis: A Systematic and Critical Analysis Review

BACKGROUND

Postoperative nausea and vomiting (PONV) affects patient satisfaction, health care costs, and hospital stay by complicating the postoperative recovery period after adolescent idiopathic scoliosis (AIS) spinal fusion surgery. Our goal was to identify recommendations for optimal management of PONV in AIS patients undergoing posterior spinal fusion (PSF).

METHODS

We performed a systematic review in June 2022, searching the PubMed and Embase electronic databases using search terms "(Adolescent idiopathic scoliosis) AND (Postoperative) AND (Nausea) AND (Vomiting)." Three authors reviewed the 402 abstracts identified from January 1991 to June 2022. Studies that included adolescents or young adults (<21 years) with AIS undergoing PSF were selected for full-text review by consensus. We identified 34 studies reporting on incidence of PONV. Only 6 studies examined PONV as the primary outcome, whereas remaining were reported PONV as a secondary outcome. Journal of Bone and Joint Surgery Grades of recommendation were assigned to potential interventions or clinical practice influencing incidence of PONV with respect to operative period (preoperative, intraoperative, and postoperative period) on the basis that potential guidelines/interventions for PONV can be targeted at those periods.

RESULTS

A total of 11 factors were graded, 5 of which were related to intervention and 6 were clinical practice-related. Eight factors could be classified into the operative period-1 in the intraoperative period and 7 in the postoperative period, whereas the remaining 3 recommendations had overlapping periods. The majority of grades of recommendations given were inconclusive or conflicting. The statement that neuraxial and postoperative systemic-only opioid therapy have a similar incidence of PONV was supported by good (Grade A) evidence. There was fair (Grade B) and poor evidence (Grade C) to avoid opioid antagonists and nonopioid local analgesia using wound catheters as PONV-reducing measures.

CONCLUSION

Although outcomes after spinal fusion for AIS have been studied extensively, the literature on PONV outcomes is scarce and incomplete. PONV is most commonly included as a secondary outcome in studies related to pain management. This study is the first to specifically identify evidence and recommendations for interventions or clinical practice that influence PONV in AIS patients undergoing PSF. Most interventions and clinical practices have conflicting or limited data to support them, whereas others have low-level evidence as to whether the intervention/clinical practice influences the incidence of PONV. We have identified the need for expanded research using PONV as a primary outcome in patients with AIS undergoing spinal fusion surgery.

Impact of timing of preoperative gabapentin administration on postoperative somnolence

Context

Enhanced Recovery After Surgery (ERAS) is a multimodal protocol aimed to improve quality of postoperative recovery, minimize complications, and optimize overall self-regulation. Preoperative gabapentin decreases postoperative pain but can be associated with prolonged postoperative somnolence and respiratory depression risk. Although it is known that gabapentin affects the postoperative course, it is unclear if the timing of preoperative administration affects this finding.

Objectives

This study aims to assess the optimal preoperative timing for gabapentin administration in patients undergoing gynecologic surgery to minimize postoperative somnolence risk.

Methods

A retrospective cohort study evaluated patients who underwent major gynecologic surgery and received preoperative gabapentin. Patients were grouped based on timing from gabapentin administration to surgical incision (<4 h group vs. ≥4 h group). Preoperative, intraoperative, and postoperative data were abstracted and compared. Univariate associations between the timing of gabapentin administration and the patient and surgical characteristics and outcomes were tested utilizing two-sample equal-variance t-tests, linear model ANOVA, or Fisher’s exact tests. Associations between the timing of gabapentin administration and the time until the Richmond Agitation Sedation Scale (RASS) score of 0 were modeled utilizing linear regression, adjusted for age, initial postoperative anesthesia care unit (PACU), RASS score, and postoperative narcotics.

Results

Each group contained 127 patients. Demographics were similar except for age (<4 h group mean=44.2 years; ≥4 h group mean=40.5 years; p=0.021), chronic pain (<4 h group=17.6%; ≥4 h group=43.3%; p<0.001), and surgical indication (<4 h group=pelvic pain [29.1%]; ≥4 h group=pelvic pain [51.2%]; p=0.007). The <4 h group had a similar postoperative narcotic administration (<4 h group mean morphine milligram equivalents [MME]=3.667; ≥4 h group mean MME=4.833; p=0.185). The minutes from surgical closure until the patient received a RASS score of 0 and initial PACU pain score (Visual Analogue Scale [VAS]) were similar. The initial PACU oxygen administration volume, hours from surgical closure until the patient transitioned to room air, and initial PACU respiratory rate were similar. The PACU duration, admission secondary to somnolence, and initial PACU Glasgow Coma Scale (GCS) score showed no difference. Postoperative nausea/vomiting was decreased in the ≥4 h group (<4 h group=24.4%; ≥4 h group=13.4%; p-value=0.036), and urinary retention (<4 h group=14.2%; ≥4 h group=5.5%; p-value=0.033) was decreased in the ≥4 h group.

Conclusions

The timing of gabapentin administration less than or more than 4 h preoperatively in patients ≥18 years does not significantly affect postoperative somnolence or respiratory depression. Further, it does not have a significant effect on GCS scores or VAS scores.

Cardiac Enhanced Recovery After Surgery: Early Outcomes in a Community Setting

BACKGROUND

Enhanced Recovery After Surgery (ERAS) programs have demonstrated improved outcomes in non-cardiac surgery. More recently, ERAS has been applied to cardiac surgery with promising results. We have implemented cardiac ERAS at our community-based program, aiming to improve all phases of care, and now report our early results.

METHODS

We retrospectively analyzed 73 consecutive patients treated with ERAS care compared to 74 patients treated prior to implementing ERAS. Our ERAS program consisted of 6 perioperative care bundles including enhanced patient education, shortened preoperative fasting period and oral carbohydrate load, postoperative nausea prophylaxis, multimodal opioid-sparing analgesia, early extubation, and early mobilization.

RESULTS

ERAS patients required significantly less opioids captured as total milligram morphine equivalents (MME; median: 35.0 versus 75.3, P < .001), less nausea as determined by fewer total ondansetron rescue doses (median 0 versus 0.5, P = .011), and less lightheadedness (P = .028) compared with pre-ERAS patients. Postoperative mobility was significantly better (POD 4: 95% vs 81%, P = .013) and postoperative length of stay was lower for ERAS care, but did not reach statistical significance (median 4 vs 5 days, P = .06). There was no difference in pain or glucose control or in early extubation.

CONCLUSIONS

Cardiac ERAS significantly decreased opioid use, nausea, lightheadedness and improved functional outcome for cardiac surgical patients in a community hospital.

Perioperative Gabapentin in Pediatric Thoracic Surgery Patients-Randomized, Placebo-Controlled, Phase 4 Trial

OBJECTIVE

To determine whether the use of perioperative gabapentin reduces postoperative pain and anxiety, decreases ropivacaine consumption and side effects, and improves patient satisfaction.

DESIGN

Randomized, placebo-controlled, phase 4 trial.

BLINDING

Participants, care providers, investigators, data analysts.

SETTING

Department of Thoracic Surgery of the Institute of Tuberculosis and Lung Disease, Rabka Zdrój Branch, Poland.

SUBJECTS

Forty patients undergoing the Ravitch procedure.

METHODS

Patients aged nine to 17 years were randomized into a gabapentin (preoperative 15 mg/kg, treatment) or placebo group. Postoperative analgesia included gabapentin (7.5 mg/kg) or placebo two times per day for three days, epidural ropivacaine + fentanyl, paracetamol, nonsteroidal anti-inflammatory drugs, and metamizol as a "rescue drug." Pain, anxiety, analgesic consumption, side effects, and patient satisfaction were recorded.

RESULTS

There was no statistically significant difference in median pain scores (numerical rating scale < 1/10) or incidence of adverse side effects between the gabapentin group (N = 20) and the placebo group (N = 20). Postoperative anxiety scores were significantly lower than before surgery in the gabapentin group (6 [4-8] vs 7 [6-8.5], P < 0.01) and remained unchanged in the placebo group (6 [5-6.5] vs 6 [5-7], P = 0.07). Gabapentin-treated patients received a lower number of doses of ondansetron when compared with the placebo group (6 [5-6] vs 7 [6-9], P = 0.02). A significant negative association was found between patient satisfaction and postoperative state anxiety in the gabapentin group (R = -0.51, P = 0.02).

CONCLUSIONS

Perioperative administration of gabapentin resulted in a decrease of postoperative anxiety in pediatric patients undergoing the Ravitch procedure.

A Comparative Study Between Ondansetron and Gabapentin for Prevention of Postoperative Nausea and Vomiting Following Maxillofacial Surgery

Background and Aim

Gabapentin is an antiepileptic drug with antiemetic properties. We evaluated prophylactic oral gabapentin as compared with ondansetron for postoperative nausea and vomiting (PONV) in patients undergoing maxillo facial surgery.

Settings and Design

A double-blind, randomized study in a teaching hospital.

Materials and Methods

Seventy patients of ASA physical status I and II, scheduled to undergo maxillofacial surgery, were randomly assigned into two groups to receive 300 mg gabapentin or 8 mg ondansetron 1 h before surgery. Standard anaesthesia technique was used in all patients. Students' t test for difference of means between two groups was used for continuous variables. Chi square or Fisher's exact test was used for comparing proportion between two groups. Kaplan-Meier survival analysis was performed to compare the time to event observed between ondansetron and gabapentin groups. Log-rank test was performed to detect statistical significance of time to events between two groups.

Results

There was no significant difference in incidence of PONV between two groups within 2 h postoperatively. No incidence of PONV was observed in gabapentin group within 2-24 h as compared to ondansetron group in which PONV was observed in five cases.

Conclusion

Gabapentin effectively suppresses PONV in maxillo facial surgery.

Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network meta-analysis

BACKGROUND

Postoperative nausea and vomiting (PONV) is a common adverse effect of anaesthesia and surgery. Up to 80% of patients may be affected. These outcomes are a major cause of patient dissatisfaction and may lead to prolonged hospital stay and higher costs of care along with more severe complications. Many antiemetic drugs are available for prophylaxis. They have various mechanisms of action and side effects, but there is still uncertainty about which drugs are most effective with the fewest side effects.

OBJECTIVES

• To compare the efficacy and safety of different prophylactic pharmacologic interventions (antiemetic drugs) against no treatment, against placebo, or against each other (as monotherapy or combination prophylaxis) for prevention of postoperative nausea and vomiting in adults undergoing any type of surgery under general anaesthesia • To generate a clinically useful ranking of antiemetic drugs (monotherapy and combination prophylaxis) based on efficacy and safety • To identify the best dose or dose range of antiemetic drugs in terms of efficacy and safety SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP), ClinicalTrials.gov, and reference lists of relevant systematic reviews. The first search was performed in November 2017 and was updated in April 2020. In the update of the search, 39 eligible studies were found that were not included in the analysis (listed as awaiting classification).

SELECTION CRITERIA

Randomized controlled trials (RCTs) comparing effectiveness or side effects of single antiemetic drugs in any dose or combination against each other or against an inactive control in adults undergoing any type of surgery under general anaesthesia. All antiemetic drugs belonged to one of the following substance classes: 5-HT₃ receptor antagonists, D₂ receptor antagonists, NK₁ receptor antagonists, corticosteroids, antihistamines, and anticholinergics. No language restrictions were applied. Abstract publications were excluded.

DATA COLLECTION AND ANALYSIS

A review team of 11 authors independently assessed trials for inclusion and risk of bias and subsequently extracted data. We performed pair-wise meta-analyses for drugs of direct interest (amisulpride, aprepitant, casopitant, dexamethasone, dimenhydrinate, dolasetron, droperidol, fosaprepitant, granisetron, haloperidol, meclizine, methylprednisolone, metoclopramide, ondansetron, palonosetron, perphenazine, promethazine, ramosetron, rolapitant, scopolamine, and tropisetron) compared to placebo (inactive control). We performed network meta-analyses (NMAs) to estimate the relative effects and ranking (with placebo as reference) of all available single drugs and combinations. Primary outcomes were vomiting within 24 hours postoperatively, serious adverse events (SAEs), and any adverse event (AE). Secondary outcomes were drug class-specific side effects (e.g. headache), mortality, early and late vomiting, nausea, and complete response. We performed subgroup network meta-analysis with dose of drugs as a moderator variable using dose ranges based on previous consensus recommendations. We assessed certainty of evidence of NMA treatment effects for all primary outcomes and drug class-specific side effects according to GRADE (CINeMA, Confidence in Network Meta-Analysis). We restricted GRADE assessment to single drugs of direct interest compared to placebo.

MAIN RESULTS

We included 585 studies (97,516 randomized participants). Most of these studies were small (median sample size of 100); they were published between 1965 and 2017 and were primarily conducted in Asia (51%), Europe (25%), and North America (16%). Mean age of the overall population was 42 years. Most participants were women (83%), had American Society of Anesthesiologists (ASA) physical status I and II (70%), received perioperative opioids (88%), and underwent gynaecologic (32%) or gastrointestinal surgery (19%) under general anaesthesia using volatile anaesthetics (88%). In this review, 44 single drugs and 51 drug combinations were compared. Most studies investigated only single drugs (72%) and included an inactive control arm (66%). The three most investigated single drugs in this review were ondansetron (246 studies), dexamethasone (120 studies), and droperidol (97 studies). Almost all studies (89%) reported at least one efficacy outcome relevant for this review. However, only 56% reported at least one relevant safety outcome. Altogether, 157 studies (27%) were assessed as having overall low risk of bias, 101 studies (17%) overall high risk of bias, and 327 studies (56%) overall unclear risk of bias. Vomiting within 24 hours postoperatively Relative effects from NMA for vomiting within 24 hours (282 RCTs, 50,812 participants, 28 single drugs, and 36 drug combinations) suggest that 29 out of 36 drug combinations and 10 out of 28 single drugs showed a clinically important benefit (defined as the upper end of the 95% confidence interval (CI) below a risk ratio (RR) of 0.8) compared to placebo. Combinations of drugs were generally more effective than single drugs in preventing vomiting. However, single NK₁ receptor antagonists showed treatment effects similar to most of the drug combinations. High-certainty evidence suggests that the following single drugs reduce vomiting (ordered by decreasing efficacy): aprepitant (RR 0.26, 95% CI 0.18 to 0.38, high certainty, rank 3/28 of single drugs); ramosetron (RR 0.44, 95% CI 0.32 to 0.59, high certainty, rank 5/28); granisetron (RR 0.45, 95% CI 0.38 to 0.54, high certainty, rank 6/28); dexamethasone (RR 0.51, 95% CI 0.44 to 0.57, high certainty, rank 8/28); and ondansetron (RR 0.55, 95% CI 0.51 to 0.60, high certainty, rank 13/28). Moderate-certainty evidence suggests that the following single drugs probably reduce vomiting: fosaprepitant (RR 0.06, 95% CI 0.02 to 0.21, moderate certainty, rank 1/28) and droperidol (RR 0.61, 95% CI 0.54 to 0.69, moderate certainty, rank 20/28). Recommended and high doses of granisetron, dexamethasone, ondansetron, and droperidol showed clinically important benefit, but low doses showed no clinically important benefit. Aprepitant was used mainly at high doses, ramosetron at recommended doses, and fosaprepitant at doses of 150 mg (with no dose recommendation available). Frequency of SAEs Twenty-eight RCTs were included in the NMA for SAEs (10,766 participants, 13 single drugs, and eight drug combinations). The certainty of evidence for SAEs when using one of the best and most reliable anti-vomiting drugs (aprepitant, ramosetron, granisetron, dexamethasone, ondansetron, and droperidol compared to placebo) ranged from very low to low. Droperidol (RR 0.88, 95% CI 0.08 to 9.71, low certainty, rank 6/13) may reduce SAEs. We are uncertain about the effects of aprepitant (RR 1.39, 95% CI 0.26 to 7.36, very low certainty, rank 11/13), ramosetron (RR 0.89, 95% CI 0.05 to 15.74, very low certainty, rank 7/13), granisetron (RR 1.21, 95% CI 0.11 to 13.15, very low certainty, rank 10/13), dexamethasone (RR 1.16, 95% CI 0.28 to 4.85, very low certainty, rank 9/13), and ondansetron (RR 1.62, 95% CI 0.32 to 8.10, very low certainty, rank 12/13). No studies reporting SAEs were available for fosaprepitant. Frequency of any AE Sixty-one RCTs were included in the NMA for any AE (19,423 participants, 15 single drugs, and 11 drug combinations). The certainty of evidence for any AE when using one of the best and most reliable anti-vomiting drugs (aprepitant, ramosetron, granisetron, dexamethasone, ondansetron, and droperidol compared to placebo) ranged from very low to moderate. Granisetron (RR 0.92, 95% CI 0.80 to 1.05, moderate certainty, rank 7/15) probably has no or little effect on any AE. Dexamethasone (RR 0.77, 95% CI 0.55 to 1.08, low certainty, rank 2/15) and droperidol (RR 0.89, 95% CI 0.81 to 0.98, low certainty, rank 6/15) may reduce any AE. Ondansetron (RR 0.95, 95% CI 0.88 to 1.01, low certainty, rank 9/15) may have little or no effect on any AE. We are uncertain about the effects of aprepitant (RR 0.87, 95% CI 0.78 to 0.97, very low certainty, rank 3/15) and ramosetron (RR 1.00, 95% CI 0.65 to 1.54, very low certainty, rank 11/15) on any AE. No studies reporting any AE were available for fosaprepitant. Class-specific side effects For class-specific side effects (headache, constipation, wound infection, extrapyramidal symptoms, sedation, arrhythmia, and QT prolongation) of relevant substances, the certainty of evidence for the best and most reliable anti-vomiting drugs mostly ranged from very low to low. Exceptions were that ondansetron probably increases headache (RR 1.16, 95% CI 1.06 to 1.28, moderate certainty, rank 18/23) and probably reduces sedation (RR 0.87, 95% CI 0.79 to 0.96, moderate certainty, rank 5/24) compared to placebo. The latter effect is limited to recommended and high doses of ondansetron. Droperidol probably reduces headache (RR 0.76, 95% CI 0.67 to 0.86, moderate certainty, rank 5/23) compared to placebo. We have high-certainty evidence that dexamethasone (RR 1.00, 95% CI 0.91 to 1.09, high certainty, rank 16/24) has no effect on sedation compared to placebo. No studies assessed substance class-specific side effects for fosaprepitant. Direction and magnitude of network effect estimates together with level of evidence certainty are graphically summarized for all pre-defined GRADE-relevant outcomes and all drugs of direct interest compared to placebo in http://doi.org/10.5281/zenodo.4066353.

AUTHORS' CONCLUSIONS

We found high-certainty evidence that five single drugs (aprepitant, ramosetron, granisetron, dexamethasone, and ondansetron) reduce vomiting, and moderate-certainty evidence that two other single drugs (fosaprepitant and droperidol) probably reduce vomiting, compared to placebo. Four of the six substance classes (5-HT₃ receptor antagonists, D₂ receptor antagonists, NK₁ receptor antagonists, and corticosteroids) were thus represented by at least one drug with important benefit for prevention of vomiting. Combinations of drugs were generally more effective than the corresponding single drugs in preventing vomiting. NK₁ receptor antagonists were the most effective drug class and had comparable efficacy to most of the drug combinations. 5-HT₃ receptor antagonists were the best studied substance class. For most of the single drugs of direct interest, we found only very low to low certainty evidence for safety outcomes such as occurrence of SAEs, any AE, and substance class-specific side effects. Recommended and high doses of granisetron, dexamethasone, ondansetron, and droperidol were more effective than low doses for prevention of vomiting. Dose dependency of side effects was rarely found due to the limited number of studies, except for the less sedating effect of recommended and high doses of ondansetron. The results of the review are transferable mainly to patients at higher risk of nausea and vomiting (i.e. healthy women undergoing inhalational anaesthesia and receiving perioperative opioids). Overall study quality was limited, but certainty assessments of effect estimates consider this limitation. No further efficacy studies are needed as there is evidence of moderate to high certainty for seven single drugs with relevant benefit for prevention of vomiting. However, additional studies are needed to investigate potential side effects of these drugs and to examine higher-risk patient populations (e.g. individuals with diabetes and heart disease).

Management strategies for the treatment and prevention of postoperative/postdischarge nausea and vomiting: an updated review

Postoperative nausea and vomiting (PONV) and postdischarge nausea and vomiting (PDNV) remain common and distressing complications following surgery. The routine use of opioid analgesics for perioperative pain management is a major contributing factor to both PONV and PDNV after surgery. PONV and PDNV can delay discharge from the hospital or surgicenter, delay the return to normal activities of daily living after discharge home, and increase medical costs. The high incidence of PONV and PDNV has persisted despite the introduction of many new antiemetic drugs (and more aggressive use of antiemetic prophylaxis) over the last two decades as a result of growth in minimally invasive ambulatory surgery and the increased emphasis on earlier mobilization and discharge after both minor and major surgical procedures (e.g. enhanced recovery protocols). Pharmacologic management of PONV should be tailored to the patient’s risk level using the validated PONV and PDNV risk-scoring systems to encourage cost-effective practices and minimize the potential for adverse side effects due to drug interactions in the perioperative period. A combination of prophylactic antiemetic drugs with different mechanisms of action should be administered to patients with moderate to high risk of developing PONV. In addition to utilizing prophylactic antiemetic drugs, the management of perioperative pain using opioid-sparing multimodal analgesic techniques is critically important for achieving an enhanced recovery after surgery. In conclusion, the utilization of strategies to reduce the baseline risk of PONV (e.g. adequate hydration and the use of nonpharmacologic antiemetic and opioid-sparing analgesic techniques) and implementing multimodal antiemetic and analgesic regimens will reduce the likelihood of patients developing PONV and PDNV after surgery.

Trends in Gabapentin Prescribing in a Commercially Insured U.S. Adult Population, 2009-2016

BACKGROUND

Gabapentin is prescribed for a variety of conditions and is often used off label. It is important to understand the prevalence of gabapentin prescribing and the characteristics of individuals who are prescribed gabapentin, given increasing concern regarding its potential for misuse.

OBJECTIVES

To (a) examine state- and region-level prevalence and trends in gabapentin prescribing from 2009 to 2016 and (b) characterize demographic and clinical characteristics of individuals prescribed gabapentin in a nationwide population of commercially insured adults.

METHODS

This retrospective, longitudinal study examined trends in gabapentin prescribing from 2009 to 2016. The study population included individuals aged 18-64 years who were enrolled in a commercial insurance plan at any point from 2009 to 2016. Individuals who were prescribed gabapentin were defined as beneficiaries with at least 1 gabapentin prescription claim in a calendar year (CY). A cross-sectional descriptive analysis was performed to examine differences in demographic and clinical characteristics of individuals prescribed or not prescribed gabapentin in CY 2016.

RESULTS

The prevalence of gabapentin prescribing nearly doubled from 2009 to 2016. During this time, gabapentin prescribing increased in every state (range: 44%-179%). State-specific prevalence rates in 2016 varied from 12.7 to 43.9 per 1,000 beneficiaries. Overall, 2.7% of beneficiaries filled ≥ 1 gabapentin prescription in 2016. Individuals prescribed gabapentin were more likely to fill opioid prescriptions (60.8% vs. 16.5%, P < 0.01); reside in the South (53.7% vs. 47%, P < 0.01); be female (62.5% vs. 52.3%, P < 0.01); and be aged 55-64 years (41.7% vs. 21.2%, P < 0.01) compared with the comparator. Individuals who were prescribed gabapentin also had significantly higher rates of seizure disorders, neuropathic pain, mental health disorders, substance use disorders, and diabetes.

CONCLUSIONS

The prevalence of gabapentin prescribing among a U.S. privately insured population has increased steadily in recent years. Additional research should examine coprescribing of gabapentin in the context of the opioid epidemic.

DISCLOSURES

The project described in this study was supported by the NIH National Center for Advancing Translational Sciences through grant number UL1TR001998. This study was also partially supported by grant number 2017-PM-BX-K026 (Data-Driven Responses to Prescription Drug Misuse in Kentucky) awarded by the Bureau of Justice Assistance. Viewpoints or opinions in this document are those of the authors and do not necessarily represent the official position or policies of the U.S. Department of Justice or the official views of the NIH. The authors do not have any conflicts of interest to report. Portions of this study have been previously presented in poster presentations at the 2019 Academy Health Annual Research Meeting; June 2-4, 2019; Washington, DC, and the 2019 University of Kentucky Substance Use Research Day; March 3, 2019; Lexington, KY.

American Society for Enhanced Recovery and Perioperative Quality Initiative Joint Consensus Statement on Perioperative Opioid Minimization in Opioid-Naïve Patients

Surgical care episodes place opioid-naïve patients at risk for transitioning to new persistent postoperative opioid use. With one of the central principles being the application of multimodal pain interventions to reduce the reliance on opioid-based medications, enhanced recovery pathways provide a framework that decreases perioperative opioid use. The fourth Perioperative Quality Initiative brought together a group of international experts representing anesthesiology, surgery, and nursing with the objective of providing consensus recommendations on this important topic. Fourth Perioperative Quality Initiative was a consensus-building conference designed around a modified Delphi process in which the group alternately convened for plenary discussion sessions in between small group discussions. The process included several iterative steps including a literature review of the topics, building consensus around the important questions related to the topic, and sequential steps of content building and refinement until agreement was achieved and a consensus document was produced. During the fourth Perioperative Quality Initiative conference and thereafter as a writing group, reference applicability to the topic was discussed in any area where there was disagreement. For this manuscript, the questions answered included (1) What are the potential strategies for preventing persistent postoperative opioid use? (2) Is opioid-free anesthesia and analgesia feasible and appropriate for routine operations? and (3) Is opioid-free (intraoperative) anesthesia associated with equivalent or superior outcomes compared to an opioid minimization in the perioperative period? We will discuss the relevant literature for each questions, emphasize what we do not know, and prioritize the areas for future research.

Pre-medication with Gabapentin is associated with significant reductions in nausea and vomiting after shoulder arthroscopy: A meta-analysis

INTRODUCTION

Arthroscopic shoulder surgery is increasingly performed as a day case procedure. Nausea, vomiting and inadequate pain control are the most frequent reasons for reattendance or failed discharge. Gabapentin is advocated as an adjunct to mitigate these symptoms and its use in shoulder arthroscopy may provide improved post-operative symptom control. The aim of this study was to perform a meta-analysis of studies evaluating the role of gabapentin in the peri-operative management of shoulder arthroscopy.

HYPOTHESIS

Gabapentin is associated with significant improvements in post-operative nausea, vomiting and pain control after shoulder arthroscopy.

MATERIAL AND METHODS

A systematic review using Medline was conducted in accordance with the PRISMA guidelines. Randomised controlled trials studies reporting on patients >15 years old receiving either preoperative gabapentin or placebo before any shoulder arthroscopic surgery were considered for eligibility. Studies were appraised against the Consolidated Standards of Reporting Trials (CONSORT) checklist. A meta-analysis was performed using Review Manager 5.3.

RESULTS

Four randomized controlled trials were identified for inclusion (n=227). Meta-analysis demonstrated a beneficial effect of gabapentin in preventing nausea and vomiting in the postoperative period (Odds Ratio 0.30, p=0.04). However, pooled data analysis did not show significant advantage in using gabapentin for postoperative pain control (p=0.11), although one study demonstrated a significant reduction in opioid consumption after gabapentin. No significant difference was reported in post-operative dizziness or sedation between the groups.

DISCUSSION

Gabapentin did not show any significant benefit in postoperative pain control but is associated with significant reductions in post-operative nausea and vomiting after shoulder arthroscopy.

LEVEL OF EVIDENCE

I, meta-analysis.

The Effect of Gabapentin on Postoperative Pain of Orthopedic Surgery of Lower Limb by Sciatic and Femoral Blockage in Children: A Clinical Trial

Background

There are meta-analyzes in adults demonstrating the benefits of using gabapentin to improve postoperative pain in orthopedic surgeries. In pediatrics, it has never been studied.

Objectives

The aim of this study was to evaluate the use of gabapentin 10 mg/kg, orally, in postoperative analgesia, hemodynamic stability and its pre/postoperative anxiolytic effect in children subjected to unilateral inferior limb surgery.

Methods

We performed a double-blinded, randomized study. 84 patients in Albert Sabin Children's Hospital were selected for elective surgery that were divided into 2 groups: gabapentin group, who received gabapentin 1 to 2 hours before the procedure and the control group. Both groups were submitted to the same general anesthesia protocol with 0.125% bupivacaine femoral and sciatic block. Patients received scheduled dipyrone and morphine was used as the rescue analgesic up to 2/2 h. Postoperative pain was assessed using a scale appropriate for age (CRIES, CHIPPS or Wong-Baker face scale). We registered hemodynamic parameters, analgesic consumption and pre/postoperative anxiolytics.

Results

A decrease in pain intensity in the 4th and 8th postoperative hours was observed in gabapentin group, both groups had the same opioid consumption. Children in the gabapentin group had an odds ratio of 25.6 for preoperative sedation and gabapentin promoted reduction of postoperative agitation. During orotracheal intubation the gabapentin group exhibited attenuation of the hemodynamic response.

Conclusions

Gabapentin was superior to placebo in reducing postoperative pain. Children who received gabapentin were more sedated in the operating room, less agitated in the postoperative period and the autonomic response to intubation was reduced.

Perioperative duloxetine for acute postoperative analgesia: a meta-analysis of randomized trials

BACKGROUND

Multimodal analgesia is a fundamental part of modern surgery and enhanced recovery pathways. Duloxetine, a serotonin and norepinephrine reuptake inhibitor, has been validated for the treatment of chronic neuropathic pain. The evidence for duloxetine as an adjunct for the treatment of acute postoperative pain remains controversial. We conducted a meta-analysis to determine the efficacy of duloxetine in the acute perioperative setting.

METHODS

A literature search was conducted in the major databases (PubMed, EMBASE and Google Scholar) for randomized controlled trials (RCTs) evaluating duloxetine compared with placebo control for acute postoperative pain. The primary outcome was postoperative pain assessed at 2, 4, 6, 24 and 48 hours time frames. Secondary outcomes included postoperative opioid administration, as well as side effects, such as postoperative nausea/vomiting (PONV), pruritus, dizziness and headache.

RESULTS

574 patients (n=9 RCTs) were included in the analysis, divided between duloxetine (n=285 patients) and placebo (n=289 patients). Duloxetine use was associated with a significant reduction in pain scores as early as 4 (mean difference (MD) -0.9, 95% CI -1.33 to -0.47) and as late as 48 (MD -0.94, 95% CI -1.56 to -0.33) hours postoperatively compared with placebo. In addition, duloxetine was associated with a significant reduction in opioid administration at 24 (standardized MD (SMD) -2.24, 95% CI -4.28 to -0.19) and 48 (SMD -2.21, 95% CI -4.13 to -0.28) hours as well as a significant reduction in PONV (risk ratio 0.69, 95% CI 0.49 to 0.95, p=0.03) compared with placebo. There was no difference between groups in other side effects.

CONCLUSION

Duloxetine, a non-opioid neuromodulator, may provide efficacy for the treatment of acute perioperative pain. Additional prospective studies are required to establish optimal perioperative dosing regimens, role in the setting of a comprehensive multimodal analgesic plan and impact on chronic postsurgical pain.

PROSPERO REGISTRATION NUMBER

CRD42019121416.

Improved Outcomes of Enhanced Recovery After Surgery (ERAS) Protocol for Radical Cystectomy with Addition of a Multidisciplinary Care Process in a US Comprehensive Cancer Care Center

INTRODUCTION

Although enhanced recovery after surgery (ERAS) components include both anesthesia and surgical care processes, it is unclear whether a multidisciplinary approach to implementing ERAS care processes improves clinical outcomes. The addition of multidisciplinary care with anesthesiology-related components to an existing ERAS protocol for radical cystectomy at a US comprehensive cancer center provided an opportunity to compare short- and long-term outcomes.

METHODS

We retrospectively compared the outcomes of 116 consecutive patients who underwent cystectomy after implementation of a multidisciplinary ERAS protocol with those of a historical control group of 143 consecutive patients who had been treated with a surgical ERAS protocol. Length of stay, return of bowel function, rate of blood transfusion, nausea, pain, and readmission rates were examined.

RESULTS

Implementation of a multidisciplinary ERAS protocol was associated with better postsurgical symptom control, as indicated by lower rates of patient-reported nausea (P < .05). Multivariate Poisson regression analysis showed a decrease in estimated intraoperative transfusions (P ≤ .001) after adjusting for the effects of potential confounding variables. There were no statistically significant differences noted in length of stay, return of bowel function, 30- and 90-day complications, or readmissions.

CONCLUSION

This is the first study to investigate the effects of adding anesthesia ERAS components to an existing surgical ERAS protocol for radical cystectomy. We found that with the addition of anesthesia-related interventions, there was a decrease in transfusions and nausea.

Systematic Review and Meta-analysis: Sometimes Bigger Is Indeed Better

Clinicians encounter an ever increasing and frequently overwhelming amount of information, even in a narrow scope or area of interest. Given this enormous amount of scientific information published every year, systematic reviews and meta-analyses have become indispensable methods for the evaluation of medical treatments and the delivery of evidence-based best practice. The present basic statistical tutorial thus focuses on the fundamentals of a systematic review and meta-analysis, against the backdrop of practicing evidence-based medicine. Even if properly performed, a single study is no more than tentative evidence, which needs to be confirmed by additional, independent research. A systematic review summarizes the existing, published research on a particular topic, in a well-described, methodical, rigorous, and reproducible (hence "systematic") manner. A systematic review typically includes a greater range of patients than any single study, thus strengthening the external validity or generalizability of its findings and the utility to the clinician seeking to practice evidence-based medicine. A systematic review often forms the basis for a concomitant meta-analysis, in which the results from the identified series of separate studies are aggregated and statistical pooling is performed. This allows for a single best estimate of the effect or association. A conjoint systematic review and meta-analysis can provide an estimate of therapeutic efficacy, prognosis, or diagnostic test accuracy. By aggregating and pooling the data derived from a systemic review, a well-done meta-analysis essentially increases the precision and the certainty of the statistical inference. The resulting single best estimate of effect or association facilitates clinical decision making and practicing evidence-based medicine. A well-designed systematic review and meta-analysis can provide valuable information for researchers, policymakers, and clinicians. However, there are many critical caveats in performing and interpreting them, and thus, like the individual research studies on which they are based, there are many ways in which meta-analyses can yield misleading information. Creators, reviewers, and consumers alike of systematic reviews and meta-analyses would thus be well-served to observe and mitigate their associated caveats and potential pitfalls.

Guidelines for Perioperative Care in Elective Colorectal Surgery: Enhanced Recovery After Surgery (ERAS®) Society Recommendations: 2018

BACKGROUND

This is the fourth updated Enhanced Recovery After Surgery (ERAS®) Society guideline presenting a consensus for optimal perioperative care in colorectal surgery and providing graded recommendations for each ERAS item within the ERAS® protocol.

METHODS

A wide database search on English literature publications was performed. Studies on each item within the protocol were selected with particular attention paid to meta-analyses, randomised controlled trials and large prospective cohorts and examined, reviewed and graded according to Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system.

RESULTS

All recommendations on ERAS® protocol items are based on best available evidence; good-quality trials; meta-analyses of good-quality trials; or large cohort studies. The level of evidence for the use of each item is presented accordingly.

CONCLUSIONS

The evidence base and recommendation for items within the multimodal perioperative care pathway are presented by the ERAS® Society in this comprehensive consensus review.

Regulating gabapentin as a drug of abuse: A survey study of Kentucky community pharmacists

OBJECTIVES

As the number of gabapentin prescriptions has increased, so have reports of its misuse and diversion. This trend has led some states to closer monitoring of gabapentin dispensing through prescription drug monitoring programs (PDMPs). The objective of this study was to collect and analyze Kentucky community pharmacists' perceptions of gabapentin misuse and diversion, and their support or opposition to regulatory efforts to reclassify the drug as a controlled substance (CS).

METHODS

Responses were collected using an online survey sent by e-mail to all pharmacists practicing in Kentucky in August 2016. The survey collected basic demographic characteristics and pharmacists' experience with gabapentin dispensing. Descriptive statistics were calculated using question response frequencies. Pearson's chi-squared statistics were calculated to examine the distribution of support for gabapentin as a CS in Kentucky across each of the categories of the individual variables. Logistic regression was used to estimate the effects of pharmacist demographic characteristics and experiences with gabapentin on their support of gabapentin reclassification as a CS.

RESULTS

One thousand seven hundred sixty-nine surveys were collected (response rate = 34.2%). Responding community pharmacists (n = 1084) believe that the abuse and diversion of gabapentin are a problem in their communities, with 9 in 10 (89.6%) indicating that they agree or strongly agree. More than three-fourths (87.5%) indicated support for reclassifying gabapentin as a CS. Common reasons for opposition to gabapentin regulatory changes were that they would not reduce or eliminate abuse (45.8%) and that they would be an inconvenience to patients (17.0%). Pharmacists practicing in independent pharmacies and pharmacists in practice greater than 20 years were less likely to indicate support for gabapentin reclassification.

CONCLUSION

Kentucky community pharmacists express considerable concern over the possible misuse and diversion of gabapentin and widely support regulatory changes reclassifying gabapentin as a CS.

Effectiveness of preanesthetic administration of gabapentin on sedative action during intravenous sedation with propofol

PURPOSE

There are no sufficient evidences for the sedative effect of gabapentin during anesthesia, especially intravenous sedation (IVS). The purpose of this study was to evaluate the sedative effect of gabapentin as preanesthetic medication during the IVS with propofol.

METHODS

10 volunteer subjects joined this study. They underwent propofol IVS three times on separate days. On the first day, the IVS without gabapentin was performed as a control. On the second and the third day, gabapentin 200 mg and 400 mg were administered before the IVS, respectively. The target blood concentration (C_T) of propofol was gradually increased, and the bispectral index (BIS) value and Ramsay sedation score (RSS) were evaluated at each propofol C_T. Postanesthetic complications and influences on vital signs were also evaluated.

RESULTS

Compared to the control group, the propofol C_Ts in the gabapentin 400 mg group significantly reduced at the BIS values of 60 and 70 (p = 0.031 and p = 0.043, respectively), and at RSS 3, 4, 5 and 6 (p = 0.040, p = 0.004, p = 0.001 and p = 0.004, respectively). There was no significant difference in propofol C_Ts between the control group and the gabapentin 200 mg group. There were no abnormality and no deterioration in circulation and respiration in all groups. There were no significant increases in complications with the administration of gabapentin.

CONCLUSION

The oral administration of 400 mg dose of gabapentin reduced the propofol C_Ts for achieving an adequate sedation level on IVS.

Controlling postoperative use of i.v. acetaminophen at an academic medical center

PURPOSE

Results of an interprofessional formulary initiative to decrease postoperative prescribing of i.v. acetaminophen are reported.

SUMMARY

After a medical center added i.v. acetaminophen to its formulary, increased prescribing of the i.v. formulation and a 3-fold price increase resulted in monthly spending of more than $40,000, prompting an organizationwide effort to curtail that cost while maintaining effective pain management. The surgery, anesthesia, and pharmacy departments applied the Institute for Healthcare Improvement's Model for Improvement to implement (1) pharmacist-led enforcement of prescribing restrictions, (2) retrospective evaluation of i.v. acetaminophen's impact on rates of opioid-related adverse effects, (3) restriction of prescribing of the drug to 1 postoperative dose on select patient care services, and (4) guideline-driven pain management according to an enhanced recovery after surgery (ERAS) protocol. Monitored metrics included the monthly i.v. acetaminophen prescribing rate, the proportion of i.v. acetaminophen orders requiring pharmacist intervention to enforce prescribing restrictions, and prescribing rates for select adjunctive analgesics. Within a year of project implementation, the mean monthly i.v. acetaminophen prescribing rate decreased by 83% from baseline to about 6 doses per 100 patient-days, with a decline in the monthly drug cost to about $4,000. Documented pharmacist interventions increased 2.7-fold, and use of oral acetaminophen, ketorolac, and gabapentin in ERAS areas increased by 18% overall.

CONCLUSION

An interprofessional initiative at a large medical center reduced postoperative use of i.v. acetaminophen by more than 80% and yielded over $400,000 in annual cost savings.

Effect of Pregabalin Premedication on Emergence Agitation in Children after Sevoflurane Anesthesia: A Randomized Controlled Study

Background:

Emergence agitation (EA) is common in pediatrics after sevoflurane anesthesia.

Aims:

We intended to study the effect of preoperative pregabalin on EA in pediatrics after sevoflurane anesthesia.

Settings and Design:

This study design was a prospective randomized controlled double-blinded study.

Patients and Methods:

Sixty children with American Society of Anesthesiologists physical status Classes I–II, aged 4–10 years, prepared for adenotonsillectomy under sevoflurane anesthesia were randomized to two equal groups (control Group C and pregabalin Group P). Children received either placebo syrup (Group C) or pregabalin syrup 1.5 mg/kg (Group P) ½ h preoperatively. We recorded postoperative EA scale (EAS) (10, 20, and 30 min postoperatively), time to open the eye, time to extubate, postanesthesia care unit (PACU) duration of stay, number of paracetamol doses (15 mg/kg) given (to control postoperative pain), and complications as vomiting and dizziness on discharge.

Statistical Analysis Used:

Independent sample t-test and Chi-square test were used as appropriate.

Results:

Pregabalin Group P showed less EAS, less analgesic (paracetamol) requirement, and less vomiting with insignificant effects on time to open the eye or extubation and PACU duration of stay compared to control group.

Conclusion:

Preoperative pregabalin decreased postoperative EAS, analgesic (paracetamol) requirement, and vomiting in pediatrics after adenotonsillectomy using sevoflurane anesthesia without affecting time to open the eye or extubation and PACU duration of stay.

Combination of gabapentin and ramosetron for the prevention of postoperative nausea and vomiting after gynecologic laparoscopic surgery: a prospective randomized comparative study

Background

As a drug originally introduced for its anticonvulsant effects, gabapentin has been recently shown to be effective in the treatment of nausea and vomiting in various clinical settings. This study compared the antiemetic efficacy of oral gabapentin, intravenous ramosetron and gabapentin plus ramosetron in patients receiving fentanyl-based patient-controlled analgesia after laparoscopic gynecologic surgery.

Methods

One hundred and thirty two patients undergoing laparoscopic gynecologic surgery under general anesthesia were allocated randomly into three groups: group G received 300 mg oral gabapentin 1 h before anesthesia, group R received 0.3 mg intravenous ramosetron at the end of surgery, and group GR received a combination of 300 mg oral gabapentin 1 h before anesthesia and 0.3 mg intravenous ramosetron at the end of surgery. Postoperative nausea, retching, vomiting, rescue antiemetic drug use, pain, rescue analgesic requirements and adverse effects were assessed at 0–2, 2–24 and 24–48 h after surgery. Postoperative nausea and vomiting (PONV) was defined as the presence of nausea, retching or vomiting.

Results

The incidence of complete response (no PONV and no rescue antiemetics up to 48 h postoperatively) was significantly higher in group GR (26/40, 65%) than group G (16/40, 40%; P = 0.025) and group R (18/44, 41%; P = 0.027), whereas there was no significant difference between group G and group R (P = 0.932). There were no significant between-group differences in the incidence of emetic episodes, use of rescue antiemetics, severe emesis, use of rescue analgesics or any adverse effects. Postoperative pain scores were also similar among groups.

Conclusions

The combination with gabapentin and ramosetron is superior to either drug alone for prevention of PONV after laparoscopic gynecologic surgery.

Trial registration

ClinicalTrials.gov NCT02617121, registered November 25, 2015.

Postoperative nausea and vomiting: physiopathology, risk factors, prophylaxis and treatment

Recognising the importance of the prevention and early treatment of postoperative nausea and vomiting (PONV) is essential to avoid postoperative complications, improve patient satisfaction and enable the development of major outpatient surgery and fast-track surgery. The topic of PONV might seem to have become stagnant, but we are moving forward. New concepts and problems like post-discharge nausea and vomiting, new risk factors and new drugs are appearing. However, there continue to be mistaken notions about PONV, such as the association between PONV and post-anaesthesia care unit stays, or assuming that it is a risk factore characteristic of the patient, anaesthesia or surgery when it is not. Perhaps, now is the moment to tackle PONV in a different manner, implementing guidelines and going for more aggressive prophylaxis in some groups of patients. We present an extensive review of this topic.

Newest Drugs for Chronic Unexplained Nausea and Vomiting

OPINION STATEMENT

Chronic unexplained nausea and vomiting (CUNV) refers to a symptom complex defined by nausea and/or vomiting with normal diagnostic testing, including anatomic assessments (including upper endoscopy) and measures of upper gut function (e.g., gastric emptying testing). Nausea and vomiting in this condition are postulated to result from aberrant peripheral or central neurohumoral activity. A substantial subset of patients satisfies this diagnosis as more than half of individuals referred for scintigraphic testing exhibit normal gastric emptying rates. No randomized, placebo-controlled trials of any medication treatment have been performed in CUNV. However, agents with potential therapeutic benefits in CUNV include antiemetic drugs, neuromodulatory treatments which are proposed to act by reducing gastric sensitivity, and medications with prokinetic action to stimulate upper gut propulsion. Recently approved drugs with antiemetic capability include serotonin antagonists with novel modes of delivery and neurokinin antagonists with or without additional serotonergic blocking capabilities. Existing neuroleptics and pain-modifying neuromodulatory therapies with fortuitous antiemetic benefits are being considered for their benefits in this disorder. Furthermore, current investigations will define potential therapeutic actions of agents that stimulate gastric emptying via action on gastroduodenal serotonin, motilin, and ghrelin receptors. This current research may broaden the treatment options for refractory cases of unexplained nausea and vomiting.

Central Aspects of Nausea and Vomiting in GI Disorders

OPINION STATEMENT

Nausea and vomiting result from continuous interactions among gastrointestinal, central nervous system, and autonomic nervous system. Despite being closely associated, central pathways of nausea and vomiting appear to be at least partly different and nausea is no longer considered only a penultimate step of vomiting. Although our understanding of central pathways of nausea has improved over the last one decade, it is still very basic. Afferent pathways from gastrointestinal tract via vagus, vestibular system, and chemoreceptor trigger zone project to nucleus tractus solitarius which, in turn, relays the signal to central pattern generator initiating multiple downstream pathways. This central nausea pathway appears to be under constant modulation by autonomic nervous system and cerebral cortex. There is also some evidence that central pathway of chronic nausea is different from that of acute nausea and closely resembles that of neuropathic pain. This improved understanding has modified the way we can approach the treatment of acute and chronic nausea. While conventional therapies such as antiemetics (antiserotoninergic, antihistaminic, antidopaminergic) and prokinetics are commonly used to manage acute nausea, they are not as effective in improving chronic nausea. Recently, neuromodulators such as tricyclic antidepressants, gabapentin, olanzapine, benzodiazepines, and cannabinoids have been shown to have antinausea effect. There is a need to study the utility of these drugs in managing chronic functional nausea. Improving our understanding of central and peripheral circuitry of nausea will allow us to better utilize the currently available drugs and develop new therapeutic options.

Use of preoperative gabapentin significantly reduces postoperative opioid consumption: a meta-analysis

OBJECTIVES

Effective postoperative pain management is crucial in the care of surgical patients. Opioids, which are commonly used in managing postoperative pain, have a potential for tolerance and addiction, along with sedating side effects. Gabapentin's use as a multimodal analgesic regimen to treat neuropathic pain has been documented as having favorable side effects. This meta-analysis examined the use of preoperative gabapentin and its impact on postoperative opioid consumption.

MATERIALS AND METHODS

A comprehensive literature search was conducted to identify randomized control trials that evaluated preoperative gabapentin on postoperative opioid consumption. The outcomes of interest were cumulative opioid consumption following the surgery and the incidence of vomiting, somnolence, and nausea.

RESULTS

A total of 1,793 patients involved in 17 randomized control trials formed the final analysis for this study. Postoperative opioid consumption was reduced when using gabapentin within the initial 24 hours following surgery (standard mean difference -1.35, 95% confidence interval [CI]: -1.96 to -0.73; P<0.001). There was a significant reduction in morphine, fentanyl, and tramadol consumption (P<0.05). While a significant increase in postoperative somnolence incidence was observed (relative risk 1.30, 95% CI: 1.10-1.54, P<0.05), there were no significant effects on postoperative vomiting and nausea.

CONCLUSION

The administration of preoperative gabapentin reduced the consumption of opioids during the initial 24 hours following surgery. The reduction in postoperative opioids with preoperative gabapentin increased postoperative somnolence, but no significant differences were observed in nausea and vomiting incidences. The results from this study demonstrate that gabapentin is more beneficial in mastectomy and spinal, abdominal, and thyroid surgeries. Gabapentin is an effective analgesic adjunct, and clinicians should consider its use in multimodal treatment plans among patients undergoing elective surgery.