Bladder function after spinal anesthesia for cesarean section: an urodynamic evaluation

BACKGROUND: This study evaluates the effects of spinal anesthesia with hyperbaric bupivacaine plus sufentanil on bladder function in women undergoing cesarean section. SUBJECTS AND METHODS: Thirty caucasian healthy pregnants scheduled for elective Cesarean section under spinal anesthesia performed with hyperbaric bupivacaine plus sufentanil were enrolled. Filling cystometry, proprioceptive bladder sensation during cystometry, rate of spontaneous voiding, post void residual volume, anocutaneous and bulbocavernosus reflex were analyzed at 4, 6 and 8 hours after spinal anesthesia. RESULTS: The proportion of women experiencing first sensation, first desire and strong desire at 4 hours was significantly different from that reported at 6 and 8 hours (p < 0.05 for first sensation and p < 0.01 for first and strong desire). Significant differences were also observed between volumes at which first sensation arose at first measurement (4 hours) and at second and third measurements (p < 0.01). There was a significant difference in rate of spontaneous micturition, with 80% of patients at 8 hours able to spontaneously void versus 40% at 6 hours, (p < 0.01). Moreover, a lower percentage of women had absent and/or light reflexes at 4 hour than at 6 and 8 hours (p < 0.01). CONCLUSIONS: Spinal anesthesia with bupivacaine plus sufentanil causes a clinically significant disturbance on bladder function in women undergoing cesarean section. Even thought recovery of proprioceptive bladder sensation is fast, a full recovery of spontaneous voiding requires a much longer time. A close monitoring of urinary function and of bladder distension is, therefore, advisable.