Postoperative analgesia of ultrasound guided rectus sheath catheters versus continuous wound catheters for colorectal surgery: A randomized clinical trial

Purpose
The purpose of this study was to evaluate the postoperative analgesia and morphine requirements of ultrasound guided rectus sheath catheters versus continuous wound catheters in midline open colorectal surgery patients.
Methods
Sixty patients of both sexes aged 40–65 years were randomized into 2 equal groups to receive postoperative analgesia through either a wound catheter continuous infusion (group I) or rectus sheath catheters (group II). The trial is registered in the Australian New Zealand Clinical Trials Registry: ACTRN12615000636550.
Results
Heart rate and mean arterial blood pressure increased significantly in group I at 12 and 24 h as compared to time 0 and 48 h ( < 0.05). There was a significant increase in heart rate and mean arterial blood pressure in group I as compared to group II at all-time intervals ( < 0.05). There was a significant decrease in Visual analogue score at rest and with movement and in group II as compared to group I at all-time intervals ( < 0.05). Concerning the need for rescue analgesia, 8 patients (26%) in group I required rescue analgesia; 7 patients of them required only one dose and one patient required two doses. In group II two patients (6.6%) required rescue analgesia, and both required one dose. The total morphine consumption was lower and the patient satisfaction was better in group II compared with group I ( = 0.005). There were no serious complications in the two groups.
Conclusion
Ultrasound-guided rectus sheath catheters provided better postoperative analgesia compared with wound catheter continuous infusion for colorectal surgery without undesirable side effects.