A Randomised Controlled Trial of Infiltration versus Low Dose Subarachnoid Block in Hydrocele Surgery.

Background: Hydrocele surgery is a short surgical procedure requiring an anaesthetic technique that allows good surgical anaesthesia, short recovery time and minimal side effects. This study was designed to compare the traditionally used technique of local infiltration block and subarachnoid block using 1% lidocaine with 25mcg of fentanyl in patients undergoing hydrocele surgery. Methods: Sixty ASA grade I and II patients of 18-60 years of age, scheduled for hydrocele surgery were randomly assigned to two groups of 30 patients each. Group C patients received local infiltration using 1% lidocaine (maximum upto 5mg /kg) while Group I patients received intrathecal injection of 1% lidocaine with 25 mcg of fentanyl (1.5 ml of 2% lidocaine + 1 ml of normal saline + 0.5 ml fentanyl). The subjects were assessed in terms of physiological variables, the quality of analgesia, and incidence of side effects as compared to local infiltration technique. Results: Patients in group C required significantly more number of fentanyl boluses for pain as compared to patients in group I. The most common problem encountered in any group was backache with an incidence of 16.6% in group I and 6.6% in group C. Pruritus was reported to be 13.3% in group I but was absent in group C (P<0.05). However, it was mild and did not require any medication. 23 patients in group I regarded their experience of the perioperative period as excellent as compared to only 5 patients in group C. Time to void and to meet discharge criteria was comparable in both the groups. Conclusion: We conclude that the use of smaller dose lidocaine-fentanyl combination in spinal anaesthesia provides potent and excellent quality of analgesia with limited side effects without prolonging recovery as compared to 1% lidocaine infiltration in patients of hydrocele surgery.