تاثير ميزان گسترش بي حسي نخاعي هيپربار باليدوكايين 5 درصد بر روي طول مدت بلوك نخاعي

Extent of Hyperbaric Spinal Anesthetic with Lidocaine 5% Influences the Duration of Spinal Block

Introduction & Objective : Elimination of local anesthetic from subarachnoid space is probably depends on rate of local diffusional surface of anesthetic and its vascular absorption. This study was designed to evaluate the relationship between the spread of hyperbaric spinal anesthesia and duration of spinal block. Materials & Methods: To determine the effects of hyperbaric local anesthetic extension on duration of spinal block we studied 40 ASA Class I, II patients whom were candidate for elective surgery (inguinal hernia) . We randomly divided them into 2 equal groups . After performing spinal block with 2`c hyperbaric lidocaine 5% the first group was left in horizontal position and the second group in 30° torso elevated position. The patients was monitored for pulse oximetry, ECG and noninvasive BP. BP and HR were checked 5 minutes for 30 minutes and then every 15 minute until the end of study. Results: The decrease in MAP was significantly more obvious in horizontal group than 30° toros elevated group. Duration of block existing is less in horizontal group than 30° toros elevated group. Conclusion: Placing patients in 30° elevation of torso, after spinal injection, prolonged the duration of spinal block and lessen the hemodynamic changes of spinal anesthesia.