IntroductionThe aim of this systematic review was to document efficacy, safety and quality of evidence of analgesic interventions after total knee arthroplasty (TKA).MethodsThis PRISMA-compliant and PROSPERO-registered review includes all-language randomized controlled trials of medication-based analgesic interventions after TKA. Bias was evaluated according to Cochrane methodology. Outcomes were opioid consumption (primary), pain scores at rest and during mobilization, adverse events, and length of stay. Interventions investigated in three or more trials were meta-analysed. Outcomes were evaluated using forest plots, Grading of Recommendations Assessment, Development and Evaluation (GRADE), L’Abbe Plots and trial sequential analysis.ResultsThe included 113 trials, investigating 37 different analgesic interventions, were characterized by unclear/high risk of bias, low assay sensitivity and considerable differences in pain assessment tools, basic analgesic regimens, and reporting of adverse events. In meta-analyses single and continuous femoral nerve block (FNB), intrathecal morphine, local infiltration analgesia, intraarticular injection of local anaesthetics, non-steroidal anti-inflammatory drugs, and gabapentinoids demonstrated significant analgesic effects. The 24-hour morphine-sparing effects ranged from 4.2 mg (CI: 1.3, 7.2; intraarticular local anaesthetics), to 16.6 mg (CI: 11.2, 22; single FNB). Pain relieving effects at rest at 6 hours ranged from 4 mm (CI: -10, 2; gabapentinoids), to 19 mm (CI: 8, 31; single FNB), and at 24 hours from 3 mm (CI: -2, 8; gabapentinoids), to 16 mm (CI: 8, 23; continuous FNB). GRADE-rated quality of evidence was generally low.ConclusionA low quality of evidence, small sample sizes and heterogeneity of trial designs prohibit designation of an optimal procedure-specific analgesic regimen after TKA.

Gabapentin reduced opioid requirements in the first 24 h after tonsillectomy. The benefits of the reduced opioid intake may be overshadowed by the drawbacks of side-effects.

O. (2016). Gabapentin for postoperative pain management-a systematic review with meta-analyses and trial sequential analyses. This article included Trial Sequential Analyses (TSA) of the random-effects models used to adjust the confidence intervals (CI) for possible sparse data and repetitive testing. Unfortunately, due to a bug in the TSA program, the required information size (RIS) for continuous outcomes were calculated twice the correct value. There was no error in the calculations of RIS for dichotomous outcomes. However, even with an upgrade of the GRADE evaluation of the effect on the co-primary outcome of 24 hrs morphine consumption from 'very low' to 'low' the conclusions still hold and should not be changed. Accordingly, the authors present corrections for the following passages in the article: In the Abstract, Results section: