A COMPARATIVE EFFICACY STUDY OF HYPERBARIC 5-PERCENT LIDOCAINE AND 1.5-PERCENT LIDOCAINE FOR SPINAL-ANESTHESIA

We compared the clinical efficacy of 1.5% lidocaine in dextrose 7.5% i n water, which is currently available as a commercial preparation but approved for use only in obstetrical patients, with the traditional 5% lidocaine in dextrose 7.5% in water for spinal anesthesia in patients undergoing lower abdominal procedures. Fifty-one male patients schedu led to undergo inguinal herniorraphy were randomly divided into two gr oups based on the spinal anesthetic received: Group I received 1.5% li docaine in dextrose 7.5% in water, and Group II received 5% lidocaine in dextrose 7.5% in water. After intrathecal injection of the anesthet ic, each patient was evaluated for the speed of onset, the time to rec overy, and the quality of the surgical anesthesia and motor block that ensued by an anesthesiologist blinded to the technique. With the exce ption of the patients in Group I, who achieved a higher dermatome leve l of sensory analgesia, we were unable to demonstrate any significant clinical differences between the two Lidocaine solutions. Our results indicate that lidocaine 1.5% in dextrose 7.5% in water is clinically i ndistinguishable from the 5% solution as a spinal anesthetic for lower abdominal surgery. Implications: In this study, two concentrations of lidocaine are compared as spinal anesthetics in 51 male patients unde rgoing inguinal hernia repair. Patients were assessed for the onset, q uality, and duration of the spinal block. The study results indicate t hat 1.5% lidocaine is as effective as the 5% solution as a spinal anes thetic for patients undergoing inguinal hernia repair.