Comparative study of intrathecal fentanyl and midazolam for postoperative pain relief after lower abdominal surgery

Abstract

Background: For surgeries on the lower limbs and abdomen, spinal anesthesia is recommended. Due to its lower neurotoxicity, lignocaine is the most often used local anesthetic for subarachnoid blockade. Even with high sensory block, intrathecal lignocaine may not be enough to provide sustained analgesia following surgery. Therefore, a variety of adjuvants, such as fentanyl, ketamine, midazolam, clonidine, opioids, and neostigmine, are used to extend the duration of the local anesthetic's effect. Aims and objectives 1. To evaluate and compare the efficacy, utility and safety of single bolus dose of intrathecal Fentanyl (25 μ gm) and Intrathecal midazolam (2 mg) and To compare it with Control group of Placebo (0.5 ml) of normal saline in various lower abdominal surgeries under spinal anaesthesia 2. To know the quality and duration of post-operative pain relief following intrathecal fentanyl and midazolam 3. To see the incidence and severity of side effects following intrathecal administration of midazolam and fentanyl Materials and Methods: This is a prospective, parallel group clinical trial that is randomized, observer and participant blind, and prospective. Three groups were randomly assigned to 75 ASA grade I and II patients who were scheduled for lower abdominal surgery. Conclusion: Additional of intrathecal midazolam or fentanyl provided post-operative analgesia significantly longer than lignocaine alone and duration of analgesia was comparable between midazolam and fentanyl. Quality and degree of analgesia was better and both. Additional of fentanyl does not have any significant effect on onset, duration and regression of motor block. Additional of midazolam has significant effect on onset duration and regression of motor block. The onset of motor block was earlier and duration and regression of motor block was prolonged.