# Comparison of Analgesic Efficacy of Hyperbaric Levobupivacaine With or Without Clonidine in Patients Undergoing Intramedullary Nailing for Fracture Femur Under Subarachnoid Block: A Randomised Controlled Trial

## TL;DR

Adding clonidine to levobupivacaine during spinal anesthesia for femur surgery significantly extends pain relief without major side effects.

## Contribution

Demonstrates that clonidine enhances analgesic duration in subarachnoid block for femoral fracture surgery.

## Key findings

- Clonidine extended effective analgesia by 68 minutes compared to levobupivacaine alone.
- Sensory block onset and peak were significantly delayed with clonidine.
- Minimal side effects observed, with no major complications in either group.

## Abstract

Background

Subarachnoid block is the most widely used technique for lower limb surgeries because of its cost-effectiveness, good muscle relaxation, reliability, prolonged analgesia and early ambulation. Clonidine as an adjuvant for subarachnoid block may improve analgesia. So, in this study, we propose to evaluate the analgesic efficacy of hyperbaric levobupivacaine with or without clonidine in patients undergoing surgery for femoral fractures. Secondarily, we also compared sensory and motor block characteristics and noted side effects.

Methods

Subarachnoid block was given in sitting position under all aseptic precautions at the level of L2-L3 or L3-L4 intervertebral space as per the standard protocol. Intrathecal drug was given according to the group allotted as follows: Group-LC: 15 mg of 0.5% hyperbaric levobupivacaine (3 ml) + 15 mcg of clonidine (0.1 ml); Group-LN: 15 mg of 0.5% hyperbaric levobupivacaine (3 ml) + normal saline (0.1 ml)

The total volume of intrathecal drug was 3.1 ml in both groups.

Block characteristics were assessed using loss of pinprick sensation for sensory block and Modified Bromage Scale (MBS) for motor block. Hemodynamic variables were also recorded.

Results

The demographic profiles of both groups were comparable to each other with respect to gender, American Society of Anesthesiologists (ASA) grade, weight and height of patients. The duration of effective analgesia was 166.67 ±31.72 min in group LC and 98.80 ±8.99 min in group LN (p <0.001). The difference was statistically significant. The mean time of onset of sensory block was 6.53 ±1.60 min and 4.00 ±1.69 min (p =0.001); the mean time to achieve a maximum height of the sensory block was 11.53 ±3.72 min and 6.67 ±1.45 min (p <0.001) in groups LC and LN, respectively and were statistically significant. The median maximum block height was comparable in both groups. The maximum motor block achieved and motor block at the time of rescue analgesia were comparable in both groups. Intraoperative and postoperative hemodynamic parameters (heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP)) were comparable among the groups LC and LN, except in DBP at 90 mins, where in group LC the mean was 77.00 ±6.32 min and in group LN it was 81.73 ±6.25 min, which was statistically significant. Sedation scores were comparable in both groups intraoperatively and postoperatively. None of the patients had any sedation in either of the groups, and all the patients were easily arousable in group LC and group LN, respectively. No major side effects were observed in either of the groups except one patient (6.7%) in group LC and one patient (6.7%) in group LN developed nausea, and five patients (33.3%) in group LC and three patients (20.0%) in group LN had shivering, which was managed promptly.

Conclusion

Addition of 15 mcg of clonidine to 3 mL (15 mg) of 0.5% hyperbaric levobupivacaine provides a longer duration of effective analgesia with minimal side effects.