Effect of intraoperative positioning on postoperative neurological status in cats after perineal urethrostomy.

Objectives The aim of this study was to evaluate and quantify the changes in neurological status in cats after perineal urethrostomy performed in dorsal and ventral recumbency. Methods This was a prospective, randomised study. Twenty male castrated cats with feline lower urinary tract disease presented for perineal urethrostomy were enrolled in this study. Surgery was performed in either dorsal recumbency (group A) or ventral recumbency (group B). Motor response of patellar tendon, gastrocnemius muscle, pelvic limb withdrawal and perineal reflexes, as well as the presence of spinal pain in the lumbosacral region, motor function of the tail and faecal continence, were examined before surgery, and 24 h and 14 days after surgery. Results The animals had a mean weight of 5.07 +/- 1.08 kg, with a mean age of 6.12 +/- 1.85 years. Weight and age were not significantly different between groups A and B (both P = 0.897). All tested parameters of the neurological examination performed prior to surgery were considered normal in both groups (P = 1). The comparison between neurological examinations (perineal reflex and spinal pain) before and 24 h after surgery revealed a significantly decreased briskness of the perineal reflex and an increased occurrence of spinal pain 24 h after surgery (P = 0.043 and P = 0.031, respectively). However, the changes of aforementioned parameters were statistically insignificant (P = 0.249 and P = 0.141) between groups A and B. The other parameters (patellar tendon, pelvic limb withdrawal and gastrocnemius muscle reflexes, motor function of the tail and faecal continence) were statistically insignificant (P = 1) before surgery and 24 h after surgery, as well as between groups A and B 24 h after surgery. Results of all tested parameters were statistically insignificant (P = 1) before surgery and 14 days after surgery, as well as between groups A and B 14 days after surgery. Conclusions and relevance The briskness of the perineal reflex was significantly decreased and the occurrence of spinal pain significantly increased 24 h after surgery. A parallel with a low-grade positioning-dependent nerve injury as described in human medicine may be drawn. However, no positioning method was proven to be superior to the other.