Gabapentin in procedure-specific postoperative pain management - preplanned subgroup analyses from a systematic review with meta-analyses and trial sequential analyses

Enhancing analgesia in acute renal colic pain: a randomized controlled trial of gabapentin adjunct to ketorolac-based regimen

Background

Renal colic is characterized by severe pain that is highly disabling. Gabapentin, an antiepileptic medication, is often recommended as a first-line therapy for neuropathic pain. However, its effectiveness in managing somatic pain, which is defined as the result of activity by pain receptors in the deep tissues, such as renal colic pain, is not as well-established.

Method

A phase 3 randomized clinical trial was conducted to evaluate the adjuvant analgesic effects of gabapentin on acute renal colic pain. Eligible patients participated in the study via random allocation to the control or gabapentin groups using the block randomization method. All patients received a shared regimen of ketorolac and rescue morphine as the conventional analgesic treatment for renal colic pain. Gabapentin was added as an adjuvant analgesic for the gabapentin group.

Result

A total of 63 individuals with an average age of 41.35 ± 13.08, were enrolled and completed the study. At the time of admission, there were no significant differences between the baseline characteristics of two groups, with exception of weight. The gabapentin group showed a significantly higher percentage of patients with pain severity of less than 5 after 60 and 90 min, as well as a significantly lower percentage of morphine rescue requirement and total morphine intake (mg) and mg/kg.

Conclusion

In cases of acute renal colic, gabapentin significantly decreases both the amount of morphine required and the degree of pain, indicating that it may be a useful adjutant to standard analgesic regimens. Treatment regimens that include gabapentin may help individuals manage their pain and become less reliant on opioids.

Clinical Trial Registration

https://irct.behdasht.gov.ir/trial/56066, identifier: IRCT20200322046833N2.

Sixth Annual Enhanced Recovery After Surgery Symposium highlights: work in progress or standard care?

Enhanced Recovery After Surgery (ERAS) protocols have demonstrated effectiveness in accelerating patient recovery and improving outcomes. Since the systemwide implementation of ERAS protocols at Baylor Scott & White Health, an annual multidisciplinary conference has provided a review of outcomes and advancements in the ERAS program. This meeting, coined the ERAS symposium, allows providers who utilize recovery protocols to collaborate with national and international leaders in the field to improve the clinical care of patients. The sixth annual ERAS symposium was held on February 10, 2023, and provided key presentations that discussed the latest results from ERAS efforts across multiple surgical specialties along with updates in anesthesia, nursing, and nutrition. A summary of those presentations, which included perioperative glycemic control, misconceptions in pain management, and emerging ERAS protocols in different surgical specialties, is provided to document the system progress.

Regional anesthesia and acute perioperative pain management in thoracic surgery: a narrative review

Background and Objective

Thoracic surgery causes significant pain which can negatively affect pulmonary function and increase risk of postoperative complications. Effective analgesia is important to reduce splinting and atelectasis. Systemic opioids and thoracic epidural analgesia (TEA) have been used for decades and are effective at treating acute post-thoracotomy pain, although both have risks and adverse effects. The advancement of thoracoscopic surgery, a focus on multimodal and opioid-sparing analgesics, and the development of ultrasound-guided regional anesthesia techniques have greatly expanded the options for acute pain management after thoracic surgery. Despite the expansion of surgical techniques and analgesic approaches, there is no clear optimal approach to pain management. This review aims to summarize the body of literature regarding systemic and regional anesthetic techniques for thoracic surgery in both thoracotomy and minimally invasive approaches, with a goal of providing a foundation for providers to make individualized decisions for patients depending on surgical approach and patient factors, and to discuss avenues for future research.

Methods

We searched PubMed and Google Scholar databases from inception to May 2021 using the terms “thoracic surgery”, “thoracic surgery AND pain management”, “thoracic surgery AND analgesia”, “thoracic surgery AND regional anesthesia”, “thoracic surgery AND epidural”. We considered articles written in English and available to the reader.

Key Content and Findings

There is a wide variety of strategies for treating acute pain after thoracic surgery, including multimodal opioid and non-opioid systemic analgesics, regional anesthesia including TEA and paravertebral blocks (PVB), and a recent expansion in the use of novel fascial plane blocks especially for thoracoscopy. The body of literature on the effectiveness of different approaches for thoracotomy and thoracoscopy is a rapidly expanding field and area of active debate.

Conclusions

The optimal analgesic approach for thoracic surgery may depend on patient factors, surgical factors, and institutional factors. Although TEA may provide optimal analgesia after thoracotomy, PVB and emerging fascial plane blocks may offer effective alternatives. A tailored approach using multimodal systemic therapies and regional anesthesia is important, and future studies comparing techniques are necessary to further investigate the optimal approach to improve patient outcomes.

Meta-analyses of gabapentinoids for pain management after knee arthroplasty: A caveat emptor? A narrative review

The use of gabapentinoids for perioperative pain management after total knee arthroplasty has been the subject of nine systematic reviews and meta-analyses. A critical analysis of the clinical aspects of the methodology of these publications shows major flaws which limit the interpretation for the recommended use of perioperative gabapentinoids in pain management for unilateral primary total knee arthroplasty. Consequently, readers and authors of systematic reviews and meta-analyses should critically assess the clinical aspects of the included studies.

Association of gabapentinoid utilization with postoperative pulmonary complications in gynecologic surgery: a retrospective cohort study

OBJECTIVE

To investigate gabapentinoid utilization and association with postoperative pulmonary complications after gynecologic surgery.

METHODS

After Institutional Review Board approval, we performed this retrospective cohort study using the Premier Healthcare Database. We used ICD-10 and charge codes to identify adults who underwent elective gynecologic surgery from 2015 to 2018 and received either gabapentin or pregabalin on the day of surgery. Our primary outcome was a composite of pulmonary complications: respiratory failure, pneumonia, reintubation, pulmonary edema, and non-invasive or invasive ventilation. Secondary outcomes included mortality, intensive care unit admission, mechanical or non-invasive ventilation, hospital length of stay, re-admission within 30 days, opioid consumption and antiemetic use. Multivariable generalized linear mixed models were utilized to examine the associations between gabapentinoids and our outcome measures, adjusted for all covariates.

RESULTS

Data from 253,013 patients were analyzed, with 19,121 (7.6%) receiving gabapentinoids. Gabapentinoid utilization increased from 3.9% in 2015 to 12.3% in 2018, and was associated with increased pulmonary complications (OR 1.19; 95% CI 1.03-1.38), non-invasive ventilation (odds ratio [OR] 1.53; 95% CI 1.29-1.81), duration of hospital stay (% change 1.75; 95% CI 0.92-2.59), daily antiemetic doses on day of surgery (mean difference [MD] 1.37; 95% CI 1.26-1.49) and subsequently (MD 1.61; 95% CI 1.30-1.99), and higher daily average (MD 4.59 mg; 95% CI 3.55-5.63) and total (MD 8.74 mg; 95% CI 6.83-10.62) parenteral morphine equivalents.

CONCLUSIONS

Gabapentinoid utilization in gynecologic surgery is increasing and is associated with postoperative pulmonary complications.

Perioperative Use of Gabapentinoids for the Management of Postoperative Acute Pain

Background

Widely used for acute pain management, the clinical benefit from perioperative use of gabapentinoids is uncertain. The aim of this systematic review was to assess the analgesic effect and adverse events with the perioperative use of gabapentinoids in adult patients.

Methods

Randomized controlled trials studying the use of gabapentinoids in adult patients undergoing surgery were included. The primary outcome was the intensity of postoperative acute pain. Secondary outcomes included the intensity of postoperative subacute pain, incidence of postoperative chronic pain, cumulative opioid use, persistent opioid use, lengths of stay, and adverse events. The clinical significance of the summary estimates was assessed based on established thresholds for minimally important differences.

Results

In total, 281 trials (N = 24,682 participants) were included in this meta-analysis. Compared with controls, gabapentinoids were associated with a lower postoperative pain intensity (100-point scale) at 6 h (mean difference, −10; 95% CI, −12 to −9), 12 h (mean difference, −9; 95% CI, −10 to −7), 24 h (mean difference, −7; 95% CI, −8 to −6), and 48 h (mean difference, −3; 95% CI, −5 to −1). This effect was not clinically significant ranging below the minimally important difference (10 points out of 100) for each time point. These results were consistent regardless of the type of drug (gabapentin or pregabalin). No effect was observed on pain intensity at 72 h, subacute and chronic pain. The use of gabapentinoids was associated with a lower risk of postoperative nausea and vomiting but with more dizziness and visual disturbance.

Conclusions

No clinically significant analgesic effect for the perioperative use of gabapentinoids was observed. There was also no effect on the prevention of postoperative chronic pain and a greater risk of adverse events. These results do not support the routine use of pregabalin or gabapentin for the management of postoperative pain in adult patients.

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Perioperative Multimodal Analgesia Reduces Opioid Use Following Skin Grafting in Nonintubated Burn Patients

Hundreds of patients are treated for burn injuries each year at University of Wisconsin School of Medicine and Public Health. Pain management is particularly challenging during dressing changes and following skin grafting procedures. We performed a retrospective chart review from January 2011 through June 2018 to evaluate the effect of nonopioid analgesic medications on opioid use in nonintubated patients. Our primary outcome was the change in opioid use following the procedure. We found that most patients (69%) report severe pain (Numeric Rating Scale ≥7) immediately after autologous skin grafting. On average, patients required an additional 52 mg of oral morphine equivalents (ME) in the 24 h after the procedure compared with the 24 h before. The use of perioperative nonopioid analgesia varied between patients (acetaminophen 29%, gabapentin 29%, ketamine 35%, and all three 8%). Patients who received either gabapentin or a combination of acetaminophen, gabapentin, and ketamine had a smaller increase in their opioid use than patients who did not receive the medications (-25 ME, 95% confidence interval [-46, -4]; P = .018 and -47 ME, [-81, -11]; P = .010, respectively). These results support using a combination of acetaminophen, gabapentin, and ketamine for perioperative analgesia in burn patients undergoing autologous skin grafting.

Acute Experimental Pain Responses in Methadone- and Buprenorphine/Naloxone-Maintained Patients Administered Additional Opioid or Gabapentin: A Double-Blind Crossover Pilot Study

Objective

The study objective was to identify the analgesic efficacy of three different pharmacological strategies in patients receiving methadone or buprenorphine as opioid agonist treatment (OAT). The three pharmacological approaches, a) increasing maintenance methadone/buprenorphine dose by 30%, b) adding oxycodone, or c) adding a single dose of gabapentin, were compared with a control condition of the participant’s usual OAT dose.

Design

A randomized, controlled, double-blinded, double-dummy, within-subject crossover study.

Subjects

Nine participants on stable doses of methadone and eight participants on stable doses of buprenorphine were recruited.

Setting

An outpatient opioid treatment clinic in inner city Sydney, Australia.

Methods

The cold pressor tolerance test was used to examine experimental pain threshold and tolerance. Ratings of subjective drug effects and safety measures (physiological and cognitive) were assessed.

Results

There was no difference in the primary outcome measures of pain thresholds or tolerance between the conditions examined. Interindividual variability was evident. Differences in some subjective measures were identified, including lower pain recall, lower “bad effects,” and higher global satisfaction in the additional methadone condition. In the buprenorphine arm, increased drug liking and “bad effects” were detected with oxycodone administration, while increased subjective intoxication was identified with gabapentin.

Conclusions

There was no evidence of an objective improvement in analgesia with any condition compared with control. Further research is required to optimize pain management strategies in this population.

Perioperative use of gabapentinoids for the management of postoperative acute pain: protocol of a systematic review and meta-analysis

BACKGROUND

Opioids are commonly used for the management of postoperative pain, but their use is limited by important adverse events, such as respiratory depression and the potential for addiction. Multimodal opioid-sparing analgesia regimens can be effectively employed to manage postoperative pain and reduce exposure to opioids. Gabapentinoids (pregabalin and gabapentin) represent an attractive class of drugs for use in multimodal regimens. The American Pain Society recommends the use of gabapentinoids during the perioperative period; however, evidence to inform such a recommendation is unclear.

METHODS

We will conduct a systematic review and meta-analysis of randomized clinical trials evaluating the use of systemic gabapentinoids, in comparison to other analgesic regimens or placebo in adult patients undergoing surgery. We will search MEDLINE, Embase, the Cochrane Central Register of Controlled Trials (CENTRAL), the Web of Science, and ClinicalTrials.gov databases for relevant citations. Our primary outcome will be intensity of postoperative acute pain (12 h). Our secondary outcomes will be postoperative pain intensity at 6, 24, 48 h, and 72 h, cumulative dose of opioids administered within 24, 48, and 72 h following surgery, the length of stay, chronic pain, and adverse events. Two investigators will independently select trials and extract data. We will evaluate the risk of bias of included trials using the Cochrane risk of bias tools. We will represent pooled continuous data as weighted mean differences and pooled dichotomous data as risk ratios with a 95% confidence interval. We will use random effect models and assess statistical heterogeneity with the I2 index.

DISCUSSION

Our study will provide the best level of evidence to inform the effect of gabapentinoids in the management of postoperative acute pain.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42017067029.

Dose-related beneficial and harmful effects of gabapentin in postoperative pain management - post hoc analyses from a systematic review with meta-analyses and trial sequential analyses

Background

During the last 15 years, gabapentin has become an established component of postoperative pain treatment. Gabapentin has been employed in a wide range of doses, but little is known about the optimal dose, providing the best balance between benefit and harm. This systematic review with meta-analyses aimed to explore the beneficial and harmful effects of various doses of gabapentin administered to surgical patients.

Materials and methods

Data in this paper were derived from an original review, and the subgroup analyses were predefined in an International Prospective Register of Systematic Reviews published protocol: PROSPERO (ID: CRD42013006538). The methods followed Cochrane guidelines. The Cochrane Library’s CENTRAL, PubMed, EMBASE, Science Citation Index Expanded, Google Scholar, and FDA database were searched for relevant trials. Randomized clinical trials comparing gabapentin versus placebo were included. Four different dose intervals were investigated: 0–350, 351–700, 701–1050, and >1050 mg. Primary co-outcomes were 24-hour morphine consumption and serious adverse events (SAEs), with emphasis put on trials with low risk of bias.

Results

One hundred and twenty-two randomized clinical trials, with 8466 patients, were included. Sixteen were overall low risk of bias. No consistent increase in morphine-sparing effect was observed with increasing doses of gabapentin from the trials with low risk of bias. Analyzing all trials, the smallest and the highest dose subgroups demonstrated numerically the most prominent reduction in morphine consumption. Twenty-seven trials reported 72 SAEs, of which 83% were reported in the >1050 mg subgroup. No systematic increase in SAEs was observed with increasing doses of gabapentin.

Conclusion

Data were sparse, and the small number of trials with low risk of bias is a major limitation for firm conclusions. Taking these limitations into account, we were not able to demonstrate a clear relationship between the dosage of gabapentin and opioid-sparing or harmful effects. These subgroup analyses are exploratory and hypothesis-generating for future trialists.