Volume 2 No. 3, July 2007

Comparative Evaluation of Intrathecal Minidose Bupivacaine / Fentanyl vs. Conventional dose of Bupivacaine for Surgical Repair of Inguinal Hernia in Elderly Patients
Walid  Emara                                                                                                                                                                                                                                                                       Anaesthesia department, Faculty of Medicine, Tanta University
Tanta Med. Sc. J 2007; 2(3):19-29
Article type: Original article

Background/Aim: Spinal anesthesia is often used for surgical repair of inguinal hernia in the geriatric population. Intrathecal opioids enhance analgesia from subtherapeutic doses of local anesthetic and make it possible to achieve successful spinal anesthesia using otherwise inadequate doses of local anesthetic. This study was designed to investigate and compare whether a modification of the spinal anesthesia technique with addition of opioid to the injectate, combined with a reduction in the amount of bupivacaine versus conventional dose, could be effective procedure, with stable haemodynamics, maintain postoperative pain relief and reduce the recovery time, thus making spinal anesthesia more suitable for ambulatory inguinal herniorrhaphy. Patients and methods: Forty patients ASA physical status I-III were classified into 2 equal groups. Group 1 received intrathecal bupivacaine 5 mg plus fentanyl 20µg. Group2 received intrathecal bupivacaine 15 mg only. Comparison of the 2 groups was in accordance to time of onset, level of sensory blockade, duration of analgesia, mean arterial blood pressure, heart rate, degree of pain sensation using visual analogue scale, intraoperative and postoperative nausea and vomiting , total amount of vasopressor used and time to recovery and home discharge. Results: Our results showed that the time of onset of maximal blockade was slightly faster in the minidose group patients than the other group. The peak sensory level was higher in the conventional dose group patients. The conventional dose group patients were more likely to require treatment of hypotension than patients in the minidose bupivacaine-fentanyl group. Total amount of ephedrine requirements were in conventional dose group than the minidose bupivacaine-fentanyl group. Recovery and home discharge time was nonsignificantly prolonged in conventional dose group. Conclusion: Minidose of 5 mg bupivacaine in combination with 20 µg fentanyl provided spinal anesthesia for surgical repair of inguinal hernia in the elderly. The minidose combination caused dramatically less hypotension than 15 mg bupivacaine and nearly eliminated the need for vasopressor support of blood pressure.