Evaluation of analgesic effect of nitroglycerine added to lignocaine in intravenous regional anesthesia

• Main Authors: Shalini Kishor Thombre, Sufala Sunil Vishwasrao, Anil Dole
• Format: Article
• Language: English
• Published: Wolters Kluwer Medknow Publications 2016-01-01
• Series: Medical Journal of Dr. D.Y. Patil University
• Subjects: Intravenous regional anesthesia; lignocaine; nitroglycerine
• Online Access: http://www.mjdrdypu.org/article.asp?issn=0975-2870;year=2016;volume=9;issue=2;spage=190;epage=194;aulast=Thombre

Background: In this study, we used nitroglycerine (NTG) as an adjuvant to lignocaine in intravenous regional anesthesia (IVRA) to enhance the analgesic property of lignocaine. Aim: To evaluate the effect of addition of NTG to lignocaine in IVRA. Objective: To find out the onset, duration, and requirement of postoperative analgesics with the addition of NTG. Materials and Methods: This was a randomized (block randomization), double-blinded, placebo-controlled study of 60 patients of the American Society of Anesthesiologists Class I and II, undergoing hand and forearm surgeries. Patients received IVRA with 3 mg/kg 2% lignocaine diluted to a total volume of 40 ml to which either 150 μg NTG or equal volume of saline was added. Intraoperatively and postoperatively, pain score was evaluated using visual analog scale. The sensory and motor block onset and recovery time and the subsequent analgesic requirement in first 24 h were recorded. Results: Motor and sensory block onset time were significantly shorter (P < 0.001), and motor and sensory block recovery time were prolonged (P < 0.001) in NTG group compared to plain lignocaine group. Intra-operatively fentanyl requirement was significantly lower and quality of sensory and motor blockade was better in study group than control group (P < 0.001). In addition, patients in NTG group required significantly less number of analgesics in the first 24 h as compared to the other group. Nitrates are potent relaxers of vascular smooth muscles and act by dilating veins, arteries, and arterioles. In IVRA, most of the anesthetic agent is absorbed into the limb tissue. Thus, the local anesthetic agent reaches to the nerves and nerve endings quickly. Thus shortens the onset time and also prolongs sensory and motor blockade and reduces total analgesic consumption in first 24 h without significant side effects. Conclusion: NTG as an adjuvant to lignocaine for IVRA reduces the total analgesic consumption in first 24 h and improves sensory and motor block without side effects.