Pain management after total knee arthroplasty (TKA) varies and has been widely studied in recent years. Some randomized controlled studies have carried out to evaluate the effects of gabapentin on pain relief after TKA. However, no solid result was made about it. The purpose of this Meta-Analysis of Randomized Controlled Trials (RCTs) was to estimate the overall effect of pain control of gabapentin versus placebo after a TKA.
In summary, the administration of gabapentin was effective in decreasing postoperative narcotic consumption and the incidence of pruritus. There was a high risk of selection bias and a higher heterogeneity of knee flexion range in this analysis. More high-quality large randomized controlled trials with long follow-up period are necessary for proper comparisons of the efficacy and safety of gabapentin with placebo.Systematic review registration number: No.
BACKGROUND: Pregabalin and gabapentin are the gamma-aminobutyric acid analogs used as a part of multimodal analgesic regimen. AIM: To compare the postoperative analgesic benefits of gabapentin or pregabalin as a premedication for lower limb orthopedic surgery under combined spinal-epidural techniques. SETTINGS AND DESIGN: Randomized double-blind study. MATERIALS AND METHODS: A total of 90 patients were divided into three groups: G, P, C who received gabapentin 1200 mg, pregabalin 300 mg, and placebo, respectively 1.5 h before surgery. All patients received combined spinal-epidural block with 3 ml of 0.5% intrathecal bupivacaine. Assessment of pain was made with visual analog scale (VAS). Postoperative analgesia was provided with epidural top-ups with 2.5 ml of 0.5% bupivacaine and fentanyl 25 μg when VAS >3. Rescue analgesia in the form of injection diclofenac (75 mg) intramuscularly was given if VAS >3 even after epidural top-up. A total number of epidural top-ups, rescue analgesia, pain-free interval postspinal anesthesia, and sedation score were noted. STATISTICAL ANALYSIS: This was done using SPSS version 17. Mean and standard deviation were calculated using Chi-square test and analysis of variance. RESULTS: The total postoperative analgesic time was 7.23 h in Group G, 14.80 h in Group P, and 4.17 h in Group C. A total number of epidural top-ups were 2.43 in Group G, 0.77 in Group P, and 4.43 in Group C. CONCLUSION: Pregabalin 300 mg and gabapentin 1200 mg significantly reduce the need of postoperative rescue analgesia, epidural top-ups, and increase the duration of postspinal anesthesia without altering hemodynamics with sedation as a major side effect.
KEYWORDS: Diclofenac; gabapentin; gamma-aminobutyric acid; pain; pregabalin; visual analog scale
The purpose of this systematic review and meta-analysis of randomized controlled trials (RCTs) and non-RCTs was to evaluate the efficacy and safety of gabapentin versus placebo for pain control after total knee arthroplasty (TKA).
Based on the current meta-analysis, gabapentin exerts an analgesic and opioid-sparing effect in acute postoperative pain management without increasing the rate of dizziness and pruritus.