Effect of Ketamine in Reducing Pain after Intravenous Injection of Propofol

Background: Propofol is frequently associated with pain during intravenous injection ;which reported to occurs in 28-90% of patients , usage of ketamine as a pre-treatment with rubber tourniquet for one minute before propofol intravenous administration, significantly reduce the severity and incidence of propofol induced pain. Aims: first to evaluate the effect of pre-treatment with small dose of ketamine with venous occlusion on reducing the pain of propofol injection in adult patients, and second to find alternative to lidocaine pretreatment. Patients and methods: Informed consents were taken from ninety unpremeditated adult patients aged 20-60 years with ASA physical status classes 1 and 2; who were scheduled for elective surgery. Patients were assigned in to three equal groups each of 30 (1st Group -received intravenously 2mls normal saline, 2nd - 2mls of 1% I.V. lignocaine, 3rd - 2mls of ketamine 10 mg (i .v). Results: there was no significant differences in age ,sex or weight .The incidence of pain was 33.3% in the ketamine group as compared to 30% in the lidocaine group and 63.3% in the normal saline group , The difference between the two proportions is :63.3 - 30= 33.3 is significant because the difference is more than twice the SE ( P). (b)Saline Vs Ketamine: S E (P) = √ (63.3× 36.6)/30+ (33, 3× 66, 6)/30=12.3. The difference between two proportions =33.3 (Statistically significant) c) lidocaine Vs ketamine: S E (P) = √ (30× 70)/30+ (33, 3× 66, 6)/30 =12.00 Difference = 3.3 (no significant difference) There was no significant difference in pain score among lidocaine and ketamine groups. Although there was significant difference between group of normal saline other two groups The overall incidence and severity of pain during injection of propofol in the various groups    .The incidence of pain in saline group was 63.3% as compared to 30% and 33.3% in the lidocaine group and ketamine groups respectively. None of patients had any side effects like erythema, itching, and bradycardia. There is no significant difference in the incidence of pain between the lidocaine (30%) and ketamine (33.3%) groups. Severe pain occurred in two patients (6%) in the saline group as compared to (0 %) in both lidocaine and ketamine groups. No pain was 36.63%   in the saline group, 70% in the lidocaine group and 66.6 % in the ketamine group. Conclusion: the current study confirmed that pretreatment with intravenous 10mg ketamine with one minute venous occlusion by tourniquet reduced the incidence and severity of propofol (i.v) injection pain, and this can be an alternative for lidocaine.