Efficacy of Wound Instillation With Bupivacaine Through a Wound Catheter for Postoperative Analgesia in Laparotomy Wounds in Comparison With Conventional Intravenous Analgesics.

Introduction A laparotomy can cause severe postoperative pain, which, if treated adequately, can result in reduced incidence of lung atelectasis and ileus promoting early mobilization and faster recovery and in turn reducing the duration of hospital stays. Hence, effective postoperative analgesia is important to reduce postoperative stress and improve early surgical outcomes. Therefore, the hypothesis is based on the fact that following a midline laparotomy, instillation of local anaesthetic agent 0.25% bupivacaine through a wound catheter placed in the subcutaneous plane may provide better analgesia compared to the conventional intravenous analgesics and improve the early surgical outcomes. Methodology A prospective, comparative, quasi-experimental study was conducted on 80 patients planned for emergency or elective midline laparotomy procedures over a period of 18 months, who were randomly distributed into two groups of 40 each. The bupivacaine group consisted of 40 patients who received 10ml of 0.25% bupivacaine instilled through a wound catheter placed in the subcutaneous plane following a midline laparotomy. This was repeated every six hours for the first 24 hours followed by every 12 hours for the next 24 hours. The conventional intravenous (IV) analgesics group involved 40 patients who received conventional IV analgesics routinely used. Pain scores were recorded every four hours for 60 hours using the visual analogue scale (VAS) and dynamic visual analogue scale (DVAS). The parameters assessed were mean VAS and DVAS scores, number of rescue analgesic demands, cumulative rescue analgesic requirement, and early surgical outcomes. Wound complications were also assessed. Results Both groups shared similar demographic characteristics in terms of age, gender, comorbidities, and duration of operation. In comparison to patients who got standard IV analgesics, those who received 0.25% bupivacaine had improved postoperative analgesia. Between the two groups, there were statistically significant results in the number of rescue analgesic demands in the first 24 hours, but in the next 24 hours, it was statistically insignificant. The study also showed that bupivacaine instillation led to a significant decrease in postoperative lung complications and the length of hospital stays; however as hypothesised, it did not improve early surgical outcomes. Conclusion This modality, the instillation of bupivacaine through a wound catheter, is an efficient and technically simple method to provide optimal postoperative analgesia. It substantially reduces the need for systemic analgesics and can potentially avoid their related side effects. Hence, the armamentarium of multimodal analgesia can therefore include this method of delivering postoperative analgesia.