Effect of Transdermal Nitroglycerine on Postoperative Analgesia Following Orthopedic Surgery under Spinal Anesthesia with Sufentanil and Lidocaine

Abstract

Background and Objectives: Administration of intrathecal opioid is one of the postoperative analgesia management methods. Experimental data suggested that transdermal nitroglycerine can enhance analgesic effect of opioids. The study was done to assess the effect of transdermal nitroglycerine on analgesia of intrathecal sufentanil and lidocaine in patients undergoing orthopedic surgery. Materials and Methods: In this prospective, double blinded, clinical trial, 24 patients scheduled for plating of tibia or fibula were randomized into two groups. In all of the patients, spinal anesthesia was done with 100 mg lidocaine 5% and 5 g sufentanil. Twenty five minutes after injection, in 12 patients (nitroglycerine group) transdermal nitroglycerine patch and in the other 12 patients (placebo group) placebo patch was applied on the chest wall. Duration of analgesia, pain occurrence, analgesic consumption and visual analogue scale (VAS) within 24 hours after the operation was assessed. Results: The mean duration of analgesia was longer in nitroglycerine group (15.719.02 hrs) than the placebo group (5.080.93 hrs) (P=0.001). Pain occurrence in 24 hours after operation was 50% in nitroglycerine group and 100% in placebo group (P=0.01). The mean analgesic consumption (P=0.01) and VAS (P=0.03) was lower in the nitroglycerine group in 24 hours after operation. Conclusion: Transdermal nitroglycerine prolongs the duration of postoperative analgesia following intrathecal sufentanil and lidocaine, and reduces pain score and rescue analgesic consumption.