Efficacy and Safety of Gabapentin on Postoperative Pain Management After Bariatric Surgery: A Systematic Review and Meta-Analysis.

PURPOSE: Examine the efficacy and safety of perioperative gabapentin in bariatric surgical patients. DESIGN: Systematic Review and Meta-analysis. METHODS: An exhaustive search was conducted using PubMed, Cochrane Library, MEDLINE, CINAHL, Google Scholar, and other gray literature. Only randomized controlled trials evaluating the use of gabapentin in bariatric surgery were included. Risk ratio (RR) and mean difference (MD) were used to estimate outcomes with suitable effect models. Quality of evidence was assessed using the Risk of Bias and GRADE system. FINDINGS: Four trials consisting of 283 patients were analyzed. The use of gabapentin significantly lowered the cumulative pain score in the first 24 hours after surgery by an average of 1.04 (MD, -1.04; 95% CI, -1.45 to -0.63; P < .00001). Gabapentin also reduced the overall morphine equivalent consumption by 7.89 mg (MD, -7.89; 95% CI, -13.56 to -2.2; P = .006). However, gabapentin did not affect the incidence of PONV (RR, 0.61; 95% CI, 0.38-1.00; P = .05), somnolence (RR, 1.25; 95% CI, 0.57-2.73; P = .57), dizziness (RR, 1.01; 95% CI, 0.40-2.54; P = .99), and headache (RR, 0.76; 95% CI, 0.25-2.30; P = .62). Substantial heterogeneity, imprecision of the effect size, and potential publication bias were limitations of this review. CONCLUSIONS: The use of gabapentin is effective in the management of postoperative pain in bariatric surgery. However, there is limited data regarding the opioid-sparing effect and adverse effect profiles of gabapentin in the bariatric surgical population.

Ondansetron for Shivering after Spinal Anesthesia in Cesarean Delivery: A Systematic Review and Meta-analysis.

PURPOSE: Evaluate the efficacy of ondansetron in preventing shivering after spinal anesthesia in cesarean delivery. DESIGN: Systematic review and meta-analysis METHODS: Following the PRISMA statement, PubMed, CINAHL, Cochrane, EMBASE, Google scholar and other grey literature databases were searched for eligible studies. FINDINGS: The overall incidence of shivering after spinal anesthesia in cesarean delivery is 32%, with 24% in patients who received ondansetron compared to 40% in the placebo group. A total of 19 trials consisting of 1399 patients were evaluated. Compared to placebo, ondansetron is effective in reducing the incidence of shivering (RR, 0.47; 95% CI, 0.29 to 0.78; P = 0.003). The quality of evidence is low due to substantial heterogeneity, imprecision and suspected publication bias. Patients who received ondansetron are less likely to require rescue treatment for shivering (RR, 0.34; 95% CI, 0.15 to 0.76; P = 0.009). Also, ondansetron is associated with a lower incidence of hypotension necessitating vasopressor treatment, and nausea and vomiting with no effects on the incidence of bradycardia. CONCLUSION: Ondansetron is effective in mitigating shivering after spinal anesthesia in cesarean delivery.

Minimum Effective Dose (ED50 and ED95) of Intrathecal Hyperbaric Bupivacaine for Cesarean Delivery: A Systematic Review.

Lowering the dose of the local anesthesia significantly reduces the risks of spinal anesthesia-induced hypotension in an elective cesarean delivery. Determination of the mean effective dose of hyperbaric bupivacaine will aid clinicians in managing maternal hypotension. The systematic search of studies evaluating the mean effective dose of hyperbaric bupivacaine yielded 10 clinical trials reporting the minimum effective dose in 50% (ED50) and 95% (ED95) of patients. The up-down method and the random allocation design were the dose-finding strategies used in all trials included in the review. The calculated ED50 and ED95 of bupivacaine varied according to different patient subgroups. The estimated ED50 of hyperbaric bupivacaine with or without opioid ranged from 4.7 mg to 9.8 mg. The calculated ED95 ranged from 8.8 mg to 15 mg. Doses at the level of ED50 minimized spinal anesthesia-induced hypotension yet increased intraoperative pain supplementation, whereas doses at the level of ED95 provided adequate surgical anesthesia with increased risk of maternal hypotension. Furthermore, the addition of intrathecal administration of opioids reduced local anesthetic doses. In the clinical setting, low-dose spinal anesthesia should be used only in combination with the combined spinal-epidural technique.