Vol. 1, Issue 8, Part A (2015)

Abstract
The study evaluated 120 adult patients of either sex belonging to ASA grade 1 and 2, aged 20 to 60 years were randomly allocated into 3 groups of 40 each. Group 1 – lignocaine (L), Group 2 – lignocaine and nitoglycerine (LN), Group 3 – lignocaine and dexamethasone (LD). Patients were premedicated with 0.07 mg/kg midazolam and 0.01 mg/kg atropine which were administered intramuscularly 45 min prior to surgical procedure. They were monitored for mean arterial blood pressure (MAP), oxygen saturation (SPO2) and heart rate (HR) in the operating room. Two venous cannulae were placed, one in dorsum of the operative hand and the other in the opposite hand for crystalloid infusion. Operative hand was exsanguinated with an esmarch bandage, a double cuffed pneumatic tourniquet was placed around the upper arm and proximal cuff was inflated to 250 mm Hg. Regional anaesthesia was in group 1 (LN) 200 microgram nitroglycerine plus 3mg/kg lignocaine 2% diluted with saline to a total of 40 ml and in group 2 (LD) 8mg of dexamethasone plus 3mg/kg lignocaine 2% in 40 ml volume of normal saline and in group 3 (L) 3 mg/kg lignocaine 2% diluted in normal saline to a total of 40ml. The solution was injected over 90 seconds. Sensory block was assessed by pin prick every 30 seconds. Motor function was assessed by asking the subject to flex and extend his/her wrist and fingers. After sensory and motor block onset, the operative tourniquet (distal cuff) was inflated to 250 mmHg and the proximal tourinquet was released and surgery was started. MAP, HR and SPO2 were monitored before and after tourniquet application and in every 5 minute interval intra-operatively and after tourniquet. Assessment of tourniquet pain scores was made on the basis of the Visual Analogue Scale (VAS) {0= no pain and 10= worst pain imaginable} measured before and after tourniquet application. The demographic data of all the groups was comparable. The percentage of males and females patients was in group 1, 80% and 20% in group 2 and 77% and 23% in group 3. The mean duration of surgery in group 1 was 44.0± 10.5 minutes, in group 2 was 41.2± 9.7 minutes and group 3 was 43.3± 9 minutes. The addition of 200microgram nitroglycerine improved the speed of onset, quality of anaesthesia, prolonged the sensory and motor block recovery time, increased the duration of post-operative analgesia. The addition of 8 mg dexamethasone improved the quality of anaesthesia but did not cause significant difference in time to first request. Based on the study, it may be said that the addition of nitroglycerine and dexamethsone to lignocaine in Intra venous regional analgesia definitely improved the quality of anaesthesia.