Comparison of Intravenous Lignocaine and Dexmedetomidine for Prevention of Propofol Injection Pain

BACKGROUND This study was conducted to compare and evaluate the efficacy and safety of prior intravenous dexmedetomidine with intravenous lignocaine as pre-treatment for prevention of propofol injection pain. METHODS In this prospective, randomised and double blinded clinical study, a total of 200 patients aged between 18 and 70 years of American Society of Anaesthesiologists (ASA) grade I or II posted for elective surgery under general anaesthesia utilising propofol as the inducing agent, were randomly allocated into two groups of 100 patients each, using computer generated random number tables. Group I received intravenous lignocaine 0.2 mg / Kg and group II received intravenous dexmedetomidine 0.5 mcg / Kg respectively prior to administration of propofol (2 mg / Kg) for induction during general anaesthesia. Pain during propofol administration was assessed for each patient using the McCririck and Hunter scale. Peri-operative haemodynamic changes and side effects were noted. Data was analysed using chi-square test and a P-value < 0.05 was considered to be statistically significant. RESULTS A total of 200 patients (100 patients in lignocaine group and 100 patients in dexmedetomidine group) were studied. Statistically significant (P < 0.05) diminution in pain score was discovered to be higher in group II (dexmedetomidine) as compared to group I (lignocaine). 80 % in the dexmedetomidine group had no pain compared to 62 % of the patients in the lignocaine group which is statistically significant. Dexmedetomidine also had a more remarkable effect on the heart rate (10 minutes after intubation) compared to lignocaine, with P = 0.054 which is statistically significant. CONCLUSIONS Intravenous dexmedetomidine is a superior pre-medication compared to intravenous lignocaine in the prevention of pain following propofol administration. It also has additional properties of sedation, analgesia, anxiolysis and sympatholytic action making it a better alternative for the anaesthesiologist and the patient.