Bilateral vs. unilateral spinal anesthesia for varicose vein surgery in hypertensive patients

Background and Purpose: Cardiovascular system may be affected by spinal anaesthesia due to unavoidable sympathetic blockade. One of the most common side effect is hypotension. Hypertensive patients are particularly prone to developing hypotension during spinal anesthesia. The use of unilateral spinal anesthesia may restrict sympathetic block and avoid the undesired cardiovascular effects. The aim of this prospective, randomized study was to compare unilateral with bilateral spinal anesthesia in hypertensive patients undergoing surgery for varicose veins according to hemodynamic change. Material and Methods: Forty ASA II hypertensive patients scheduled for surgical repair of varicose veins were randomly allocated into two groups to receive bilateral (n=20) and unilateral (n=20) spinal anesthesia. Group S patients received bilateral spinal anesthesia with 3 ml isobaric 0.5% levobupivacaine (15 mg) and group US patients received unilateral spinal anesthesia with hyperbaric spinal solution (0.5% levobupivacaine 5 mg plus fentanyl 50 μg and 1ml of 10% glucose).We measured noninvasive mean arterial blood pressure and heart rate before spinal blockade and then after 5, 15, 30, and 45minutes.We also recorded the onset of motor and sensory blockade and side-effects. Results: There were no significant differences between two groups with respect to age, gender, weight, height and duration of surgery. In group S, 15 minutes after the initiation of the spinal block a statistically significant drop in the systolic and diastolic blood pressure from the baseline value was observed (p<0.05). Comparing systolic and diastolic blood pressure among groups, a statistically significant difference was also found 15 minutes after spinal injections (p