The effects of dexmedetomidine added to spinal levobupivacaine for transurethral endoscopic surgery

Intrathecal α2 agonists prolong the duration of action of local anesthetics and reduce the required dose. Dexmedetomidine is an α2 receptor agonist and its α2/α1 selectivity is 8 times higher than that of clonidine.

In this study, we aimed to investigate the effect of adding dexmedetomidine to intrathecal levobupivacaine on the onset time and duration of motor and sensory blocks.

Randomized controlled study.

Patients were randomly assigned into two groups. Group L (n= 30) patients received 3 mL (15 mg) of 0.5% levobupivacaine +0.3 mL normal saline and Group LD (n= 30) patients received 3 mL (15 mg) of 0.5% levobupivacaine + 0.3 mL (3 μg) dexmedetomidine. Sensory block onset time, block reaching time to T10 dermatome, the most elevated dermatome level, two dermatome regression time, sensory block complete regression time as well as motor block onset time, reaching Bromage 3 and regressing to Bromage 0 were recorded.

Sensory and motor block onset times were shorter in Group LD than in Group L (p<0.001). The regression of the sensory block to S1 dermatome and Bromage 0 were longer in Group LD than Group L (p<0.001). The two dermatome regression time was longer in Group LD than Group L (p< 0.001). There were no statistically significant differences between groups in blood pressure and heart rate. There was no statistically significant difference between groups when adverse effects were compared.

We conclude that intrathecal dexmedetomidine addition to levobupivacaine for spinal anaesthesia shortens sensory and motor block onset time and prolongs block duration without any significant adverse effects.