Unilateral paravertebral block: an alternative to conventional spinal anaesthesia for inguinal hernia repair
Background: Inguinal herniorrhaphy can be successfully performed using general, regional or local anaesthesia. Paravertebral block (PVB) has been used for unilateral procedures such as thoracotomy, breast surgery, chest wall trauma, hernia repair or renal surgery. Methods: We compared unilateral lumbar PVB with conventional spinal anaesthesia (SA) in 60 consenting ASA I and II males aged 18-65 years, scheduled for unilateral inguinal hernia repair. Patients were randomly assigned into two groups, P (n=30) or S (n=30) to receive either PVB or SA, respectively. Two patients (7%) in group P had to be converted to general anaesthesia due to block failure. During surgery, patients of both groups received intravenous infusion of propofol titrated to light sedation. Results: The time to first post-operative analgesic requirement (primary outcome measure) as 342 +/- 73 min in group P and 222 +/- 22 min in group S (P<0.0001). Time to ambulation was 234 +/- 111 min in group P and 361 +/- 32 min in group S (P<0.0001). Urinary retention requiring catheterization were found in zero (0%) patients in group P compared with five (16%) in group S (P=0.024). Conclusion: It can be concluded that unilateral PVB is more efficacious than conventional SA in terms of prolonging post-operative analgesia and reducing morbidities in patients undergoing elective unilateral inguinal hernia repair.