B. Kakala1,2, Z. Y. Yeh2 1University Of Sydney,General Surgery,Sydney, NSW, Australia 2Blacktown Hospital,General Surgery,Sydney, NSW, Australia
Introduction:
Post-operative pain following an open midline laparotomy is associated with significant morbidity and mortality. Multimodal analgesia aims to achieve more effective pain relief and reduce some of these adverse effects such as signficant ongoing pain, ileus, nausea and vomiting. Continuous local anaesthetic wound infusions (CLAWI) into the laparotomy wound via an indwelling wound catheter is a promising addition to a multimodal postoperative analgesic regimen. This systematic review aims to appraise and synthesise evidence from randomised controlled trials evaluating CLAWI for controlling acute postoperative pain within 24 hours following surgery.
Methods:
Medline, Embase and Central databases were searched to March 2015. References were screened by title and abstract. Full texts of trials for potential inclusion were examined. Reference lists of included trials were hand-searched for additional trials. Two authors indepedently identified trials for inclusion, assessed the quality and risk of bias of included trials, and extracted data. Any unclear or missing inforamtion was sought by contacting the corresponding authors. Where necessary, missing data was imputed according to insturctions given in the Cochrane Handbook. Meta-analysis based on a fixed effects model was performed using RevMan 5.
Results:
A total of 3537 references werwe identified. After exluding 1282 duplicates, 379 non-English references and 1847 references based on screening, 29 full texts were further examined to identify 6 trials that fulfilled the inclusion criteria. 608 participants were included for review. All except one trial had moderate to high risk of bias. Two trials compared CLAWI (n=79) to epidural analgesia (n=77). Within 24 hours, there was no significant difference between the two groups in pain (mean difference [MD] 0.13 on a 10-point scale, p=0.55). four trials compared CLAWI with local anaesthetic (LA) (n=225) versus saline (n=227). Within 24 hours, the LA group had a statistically significant reduction in both pain (MD -0.43 on a 10-point scale, p=0.05) and opioid consumption (MD -5.02mg morphine equivalent, p=0.04).
Conclusion:
CLAWI was associated with a small but statistically significant reduction in both pain and opioid consumption within 24 hours following midline laparotomy. It was non-inferior to epidural analgesia in terms of acute postoperative pain control, and is a promising alternative in situations where epidural analgesia is contraindicated, impractical, technically difficult or poorly tolerated.
