Transdermal nitroglycerine as a coadjuvant to intrathecalnalbuphine with bupivacaine in lower abdominal surgery

BackgroundThe purpose of this study was to evaluate the effect of transdermal nitroglycerine patch as a coadjuvant to intrathecal nalbuphine with bupivacaine in patients undergoing lower abdominal surgery.Patients and methodsA total of 120 patients (ASA I or II) were randomized into two equal groups in this double-blind, placebo-controlled trial. The control group (group C) received intrathecal 0.5% hyperbaric bupivacaine 15 mg (3 ml) plus 0.8 mg (0.4 ml) preservative-free nalbuphine plus transdermal placebo patch, and the study group (group NG) received intrathecal 0.5% hyperbaric bupivacaine 15 mg (3 ml) plus 0.8 mg (0.4 ml) preservative-free nalbuphine plus transdermal nitroglycerine patch (5 mg). The transdermal patch (either nitroglycerine or placebo) was applied on the chest 20 min after spinal injection. Pain intensity, hemodynamics, and adverse effects were evaluated.ResultsPatients in group NG had longer duration of effective analgesia with subsequent longer time for the first rescue analgesic (482.6 ± 16.3 min) compared with group C (334.2 ± 15.6 min) (P 0.05). Moreover, group NG required less rescue analgesics in 24 h compared with group C (P 0.05) and had lesser overall 24-h pain visual analogue scale scores. The incidence of perioperative adverse effects was similar between the two groups (P 0.05).ConclusionTransdermal nitroglycerine (5 mg) significantly prolonged the analgesic effect of intrathecalnalbuphine and provided effective postoperative analgesia after lower abdominal surgery.