Spinal anesthesia with low dose bupivacaine and fentanyl for femur surgeries in elderly patients

Background and objectives: Decreasing the dose of intrathecal Bupivacaine may be useful to provide surgical anaesthesia with less hemodynamic disturbances especially in elderly patients but may be associated with inadequate anaesthesia for orthopaedic surgeries to perform. This can be overcome by adding Fentanyl to it. Materials and method: 60 elderly patients of American Society of Anaesthesiologists (ASA) grade II, scheduled for femur surgeries were randomly assigned to one of the two groups. Group B:(n=30) patients receiving Bupivacaine (0.5%) heavy 2.5ml (12.5mg) and Group BF:(n=30) patients receiving Bupivacaine (0.5%) heavy 1.5ml (7.5mg)+Fentanyl (25ug) 0.5ml+0.5 ml normal saline, total volume being 2.5ml. The characteristics of sensory and motor blockade, duration of effective analgesia, perioperative hemodynamics and complications were recorded. Results: The mean onset of sensory block and time to achieve peak sensory level was early, time to achieve regression to L1 level and duration of effective analgesia was longer in group BF ad the difference was highly significant (p<0.001). There was no significant difference in motor blockade characteristics between two groups. Incidences of hypotension were more in group B compared to group BF. Conclusion: Low dose intrathecal bupivacaine (7.5 mg) with fentanyl (25mcg) can provide adequate surgical anaesthesia and better hemodynamics and can be used in elderly patients for femur surgeries.