Effect of Preoperative Duloxetine on Opioid Consumption in Women Undergoing Abdominal Hysterectomy: A Randomized, Double-Blinded, Placebo-Controlled Trial

Postoperative acute pain management with duloxetine as compared to placebo: A systematic review with meta-analysis of randomized clinical trials

BACKGROUND

Duloxetine has been used as an adjunct in multimodal analgesia for acute postoperative pain in clinical studies. This meta-analysis aims to conclude whether oral duloxetine, when given perioperatively, is any better than a placebo in managing postoperative pain. Effects of duloxetine on postoperative pain scores, time to first rescue analgesia, postoperative rescue analgesia consumption, side effects attributable to duloxetine, and patient satisfaction profile were assessed.

METHOD

MEDLINE, Web of Science, EMBASE, Scholar Google, and the Cochrane Central Register of Controlled Trials (CENTRAL) were searched with keywords including "Duloxetine" AND "postoperative pain", "Duloxetine" AND "acute pain" and with "Duloxetine" till October 2022. This meta-analysis included randomized clinical trials in which perioperative duloxetine 60 mg per oral was administered not more than 7 days before surgery and for at least 24 after surgery but not more than 14 days after surgery. All RCTs in which the comparator is placebo and outcomes related to analgesic efficacy like pain scores, opioid consumption, and side effects of duloxetine until 48 h postoperatively were included. Data were extracted from the studies and a risk of bias summary was formed using the Cochrane Collaboration tool. Effect sizes were given as standardized mean differences for continuous outcomes and risk ratios (RR) by the Mantel-Haenszel test for the categorical outcome. Confirmation of publication bias was done by Egger's regression test (p < 0.05). If publication bias or heterogeneity was detected, the trim-and-fill method was used to calculate the adjusted effect size. Sensitivity analysis was done by leaving one out method after excluding the study with a high risk of bias. Subgroup analysis was done based on the type of surgery and gender. The study was prospectively registered in the PROSPERO under the registration number CRD42019139559.

FINDINGS

29 studies with 2043 patients met the inclusion criteria and were reviewed for this meta-analysis. Postoperative pain scores at 24 h [Std. Mean Difference (95% CI); -0.69 (-1.07, -0.32)] and at 48 h [-1.13 (-1.68, -0.58)] are significantly less with duloxetine (p-value < 0.05). Time to first rescue analgesia was significantly more in patients where duloxetine was administered [1.27 (1.10, 1.45); p-value > 0.05]. Opioid consumption up to 24 h [-1.82 (-2.46, -1.18)] and 48 h [-2.48 (-3.46, -1.50)] was significantly less (p-value < 0.05) in patients who received duloxetine. Complications and recovery profiles were similar in patients receiving either duloxetine or a placebo.

INTERPRETATION

Based on GRADE findings, we conclude that there is low to moderate evidence to advocate the use of duloxetine for managing postoperative pain. Further trials are needed to replicate or refute these results based on robust methodology.

Analgesic efficacy and safety of duloxetine premedication in patients undergoing hysterectomy - A systematic review

Background and Aims

Patients undergoing hysterectomy by open or laparoscopic approach experience moderate to severe postoperative pain. A multimodal analgesic approach is recommended for these patients. This study reviews the analgesic efficacy of duloxetine, a selective serotonin and norepinephrine reuptake inhibitor used as an adjuvant for opioid-sparing postoperative analgesia.

Methods

After registering the protocol in the international prospective register of systematic reviews (PROSPERO), databases like PubMed, Ovid, Scopus, Cochrane Library and clinicaltrials.gov were searched for randomised controlled trials using relevant keywords to find studies in which duloxetine premedication was compared to a placebo in patients undergoing hysterectomy. The revised Cochrane risk-of-bias tool for randomised trials (RoB 2) was used to assess the quality of evidence.

Results

The qualitative systematic review included five of the 88 studies identified. The overall risk of bias in the included studies was very high. In all the studies, 60 mg oral duloxetine was used, and the control group was placebo. In two studies, duloxetine premedication was administered 2 h before and 24 h after surgery. In the other three studies, a single dose of 60 mg duloxetine was only administered 2 h before surgery. A pooled meta-analysis was not performed due to fewer studies that fulfilled the inclusion criteria and even fewer studies with consistent reporting of various outcomes.

Conclusion

The evidence is insufficient to advocate routine duloxetine premedication in patients undergoing hysterectomy.

Comparison of Perioperative Pregabalin and Duloxetine for Pain Management After Total Knee Arthroplasty: A Double-Blind Clinical Trial

BACKGROUND

Chronic residual pain after total knee arthroplasty (TKA) is one of the challenges of postoperative pain management. Duloxetine, by controlling neuropathic pain, and pregabalin, by affecting nociceptors, can effectively manage postoperative pain.

OBJECTIVES

This study aimed to compare the effect of perioperative oral duloxetine and pregabalin in pain management after knee arthroplasty.

METHODS

In this clinical trial, 60 patients scheduled for TKA under spinal anesthesia were randomly assigned to one of three groups A (pregabalin 75 mg), B (duloxetine 30 mg), and C (placebo). Drugs were administered 90 minutes before, 12, and 24 hours after surgery. The visual analog scale (VAS) score for pain, the first analgesic request time, postoperative analgesic consumption (i.v. paracetamol), and WOMAC score six months after surgery were recorded.

RESULTS

The VAS score and analgesic consumption 48 hours after TKA in groups A and B significantly decreased compared to the placebo (P < 0.05). The first analgesic request time was longer in groups A and B than in group C (P < 0.05). While the differences were statistically significant, they are most likely not clinically significant. The WOMAC score before and six months after arthroplasty did not differ between the groups (P > 0.05).

CONCLUSIONS

Perioperative oral pregabalin and duloxetine similarly reduce pain and the need for analgesic consumption within 48 hours after TKA but do not affect knee mobility status.

Endogenous opiates and behavior: 2020

This paper is the forty-third consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2020 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).

Preoperative duloxetine on postoperative pain after laparoscopic gynecological surgeries: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

To evaluate the efficacy and safety of preoperative duloxetine on postoperative pain management after gynecologic laparoscopic surgeries.

METHODS

A systematic search was done in Cochrane Library, PubMed, ISI web of science, and Scopus from inception to September 2021. We selected randomized clinical trials (RCTs) that compared preoperative duloxetine (intervention group) versus placebo (control group) among women undergoing gynecologic laparoscopic surgeries. Our primary outcomes were pain scores evaluated by the Visual Analog Scale (VAS) at 2, 6, 12, and 24 h postoperatively. Our secondary outcomes were the time required for the first analgesic request in minutes, postoperative analgesic consumption in milligrams, length of hospital stay in days, and side effects.

RESULTS

Four RCTs with a total number of 244 patients were included in our systematic review and meta-analysis. We found duloxetine was linked to a significant reduction in VAS pain scores at different time intervals. The first analgesic request was significantly earlier in the placebo group than in the duloxetine group (p = 0.03). In addition, duloxetine significantly reduced the postoperative analgesic consumption compared to placebo (MD= -41.97, 95% CI [-53.23, -30.72], p<0.001). However, both groups did not differ in the length of hospital stay and side effects.

CONCLUSIONS

Duloxetine administration prior to gynecological laparoscopic surgeries is safe and effective in improving postoperative pain and analgesia.

Conolidine: A Novel Plant Extract for Chronic Pain

Pain, the most common symptom reported among patients in the primary care setting, is complex to manage. Opioids are among the most potent analgesics agents for managing pain. Since the mid-1990s, the number of opioid prescriptions for the management of chronic non-cancer pain (CNCP) has increased by more than 400%, and this increased availability has significantly contributed to opioid diversion, overdose, tolerance, dependence, and addiction. Despite the questionable effectiveness of opioids in managing CNCP and their high rates of side effects, the absence of available alternative medications and their clinical limitations and slower onset of action has led to an overreliance on opioids. Conolidine is an indole alkaloid derived from the bark of the tropical flowering shrub Tabernaemontana divaricate used in traditional Chinese, Ayurvedic, and Thai medicine. Conolidine could represent the beginning of a new era of chronic pain management. It is now being investigated for its effects on the atypical chemokine receptor (ACK3). In a rat model, it was found that a competitor molecule binding to ACKR3 resulted in inhibition of ACKR3's inhibitory activity, causing an overall increase in opiate receptor activity. Although the identification of conolidine as a potential novel analgesic agent provides an additional avenue to address the opioid crisis and manage CNCP, further studies are necessary to understand its mechanism of action and utility and efficacy in managing CNCP.

The Effects of Intravenous Vitamin C on Stress Response Severity in Abdominal Hysterectomy Following Prolonged Fasting Time

Background

Inevitable prolonged fasting time before surgery leads to inflammatory reactions, surgery-related stress response, and consequently unfavorable outcomes; thus, developing strategies to mitigate these consequences is crucial.

Objectives

In this study, we evaluated the effect of ascorbic acid on stress response reduction in abdominal hysterectomy following prolonged fasting time.

Methods

Eligible women candidates for abdominal hysterectomy following prolonged fasting time were enrolled in the study and divided into 2 groups of vitamin C [group C; 1 g intravenously (IV) before surgery] and placebo (group P). Before induction of anesthesia, C-reactive protein (CRP), mean arterial pressure (MAP), heart rate (HR), and blood sugar (BS) were measured and compared between the 2 groups at 4-point times, 24 and 48 hours immediately after extubation.

Results

Finally, the data of 80 patients were included for the final analysis. A statistically significant difference was observed between the 2 groups in terms of CRP and BS values in T1 CRP serum levels; at the end of the study, CRP values were 0.5 ± 0.55 and 0.92 ± 0.69 in groups C and P, respectively (P = 0.012), and BS levels were 124.12 ± 18.11 and 152.0 ± 17.36 in groups C and P, respectively (P = 0.0001). However, this significant difference was not observed at T2 regarding CRP (P = 0.145) and BS (P = 0.135), as well as at T3 regarding CRP (P = 0.282) and BS (P = 0.213). However, according to both CRP and BS values, the trend of changes from T0 to T3 was significant in the 2 groups (P < 0.0001). Hemodynamic parameters were not significantly different between the 2 groups. No adverse event was reported in the 2 groups.

Conclusions

We found that ascorbic acid could induce short-term positive effects in abdominal hysterectomy following prolonged fasting time. Obviously, the optimal dosage, timing, and specific cases that benefit the most from this intervention should be investigated.

Selective serotonin reuptake inhibitors and serotonin-norepinephrine reuptake inhibitors as adjuncts for postoperative pain management: systematic review and meta-analysis of randomised controlled trials

BACKGROUND

We conducted a systematic review and meta-analysis to assess effects of selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs) as adjuncts for postoperative pain management.

METHODS

We searched seven databases and two trial registers from inception to February 2021 for RCTs that compared SSRIs or SNRIs with placebo or an active control for postoperative pain management.

RESULTS

We included 24 RCTs with 2197 surgical patients (21 trials for SNRIs and three trials for SSRIs). Moderate-quality evidence found that, compared with placebo, SSRIs/SNRIs (majority SNRIs) significantly reduced postoperative pain within 6 h {weighted mean difference (WMD) -0.73 cm on a 10 cm VAS (95% confidence interval [CI]: -1.04 to -0.42)}, 12 h (-0.68 cm [-1.28 to -0.07]), 24 h (-0.68 cm [-1.16 to -0.20]), 48 h (-0.73 cm [-1.22 to -0.23]), 10 days to 1 month (-0.71 cm [-1.11 to -0.31]), 3 months (-0.64 cm [-1.05 to -0.22]), and 6 months (-0.95 cm [-1.64 to -0.25]), and opioid consumption within 24 h (WMD -12 mg [95% CI: -16 to -8]) and 48 h (-10 mg [-15 to -5]), and improved patient satisfaction (WMD 0.49 point on a 1-4 Likert scale [95% CI: 0.09 to 0.89]) without significant increase in adverse events. Selective serotonin reuptake inhibitors tended to be less effective despite non-significant subgroup effects.

CONCLUSIONS

Serotonin-norepinephrine reuptake inhibitors as an adjunct to standard perioperative care probably provide small reduction in both acute and chronic postoperative pain and opioid consumption, and small improvement in patient satisfaction without increases in adverse events. The effects of SSRIs are inconclusive because of very limited evidence.