[Spinal anesthesia with bupivacaine for transurethral resection of prostate: effects of specific gravity, volume and...

The investigation was carried out in 80 patients scheduled for transurethral resection of prostate (TUR-P). All patients were ASA I or II, and received no premedication. Before anesthesia, elastic bandages were applied to both lower extremities and 6 mL/kg of G/S (5% Glucose in 0.9% saline solution) was administered by intravenous infusion. The patient was placed in the lateral position and dural puncture was performed at the L3-4 interspace using a standard midline approach with a 23 gauge spinal needle. The patients were allocated randomly to four groups, each group consisting of 20 patients. Three mL of 0.5% Bupivacaine was administered in group A; 3 mL of 0.5% Bupivacaine with 1 mL 10% G/W (Glucose water) in group B; 2 mL of 0.5% Bupivacaine with 1 mL 10% G/W in group C and 3 mL of 0.5% Bupivacaine in 8% glucose in group D. Assessment of the sensory and motor blockade and measurement of arterial pressure and heart rate were performed after injection. All data were analyzed by ANOVA. A p value of less than 0.05 was considered statistically significant. The results showed that the duration of analgesia with plain Bupivacaine was shorter than with hyperbaric Bupivacaine (2.59 +/- 0.81 h vs 3.12 +/- 0.72 h, P less than 0.05). The maximum cephalad spread of analgesia was lower with plain Bupivacaine (T 9 +/- 2 vs T 7 +/- 2, P less than 0.05). Patients receiving either 3 mL or 4 mL of hyperbaric bupivacaine were similar in regard to duration and maximum cephalad spread of analgesia, but the effect on the cardiovascular system was more severe in the group receiving 4 mL.(ABSTRACT TRUNCATED AT 250 WORDS)