The Use of Local Anaesthetic Wound Catheter Infiltration for Post-Operative Pain after Hepatic Surgery: A Systematic Review and Meta-analysis

Abstract

Introduction: The gold standard regime for analgesia following liver resection remains under debate. Studies have suggested that local anaesthetic (LA) infiltration via a wound catheter may provide analgesic benefits. The aim of this study was to analyse whether LA wound catheter infiltration (LA-WCI) as an adjunct to intravenous patient-controlled analgesia (IV-PCA) provides superior analgesic outcomes compared to IV-PCA alone. Methods: A systematic literature search and meta-analysis was conducted according to PRISMA guidelines. Randomised control trials (RCTs) comparing LA-WCI with IV-PCA versus IV-PCA alone were included. Primary outcomes were total opioid use in the first 48 hours and pain scores at multiple time points at rest and on exertion. Secondary outcomes were length of hospital stay, length of intensive care unit (ICU) stay, time to ambulation, time to first bowel movement, incidence of surgical site infections and incidence of nausea and vomiting. Results: Of 958 articles screened, six RCTs with a total of 440 patients were included in the meta-analysis. In all studies, IV-PCA with LA-WCI (LA-WCI group) was compared to IV-PCA alone (IV-PCA group). Total opioid use (mg morphine equivalent) via IV-PCA in the initial 48 hours post-operatively was significantly less in the LA-WCI group compared to the IV-PCA group [MD -21.27mg (-39.39, -3.15), I2 = 98%, p=0.02]. Pain scores were significantly lower in the LA-WCI group at rest at POD0 (post-operative day 0) 6-8hrs (p=0.0009), POD1 AM (p=0.01), POD 1 PM (p=0.02) and POD2 (p=0.0006), and on exertion at POD0 0-2hrs (p=0.05), POD1 AM (p=0.03), POD1 PM (p=0.03), POD2 (p=0.03) and POD3 (p=0.01), but similar at all other time points. The LA-WCI group had significantly reduced length of hospital stay [MD -1.32 days (-2.23, -0.40), I2 = 0%, p=0.005], time to ambulation [MD -5.94 hours (-8.47, -3.42), I2 = 0%, p=0.00001] and incidence of nausea and vomiting [OR 0.16 (0.06, 0.42), I2 = 0%, p=0.0002]. No significant differences were observed in length of ICU stay, time to first bowel movement and incidence of wound infection. Conclusions: LA-WCI as an adjunct to opiate IV-PCA post-hepatectomy reduces opioid use in the post-operative period, pain scores at multiple time points at rest and exertion, length of hospital stay, time to ambulation and incidence of nausea and vomiting. However, LA-WCI use does not alter length of ICU stay, time to first bowel movement and incidence of wound infection.