Supraclavicular Brachial Plexus Block: Comparison of Varying Doses of Butorphanol Combined with Levobupivacaine - A Double-Blind Prospective Randomized Trial.

BACKGROUND

The ideal dose of butorphanol for brachial plexus block is not well known.

AIMS

This study was carried out to evaluate 1 mg and 2 mg of butorphanol added to 0.375% levobupivacaine, with regard to the duration of analgesia. Our study also sought to assess the onset and duration of sensorimotor blockade, hemodynamic effects, sedation, and adverse effects.

SETTINGS AND DESIGN

This study was a prospective, randomized, double-blinded, and comparative study.

METHODS

Eighty adult patients of either sex undergoing upper limb surgeries under supraclavicular brachial plexus block were randomly allocated into two groups. Group LB1 received 29 ml of 0.375% levobupivacaine plus 1 mg of butorphanol diluted in 1 ml of normal saline. Group LB2 received 29 ml of 0.375% levobupivacaine plus 2 mg of butorphanol diluted in 1 ml of normal saline. The onset and duration of sensorimotor blockade, level of sedation, duration of analgesia, and adverse effects were assessed.

STATISTICAL ANALYSIS

The data were analyzed with Student's -test and Chi-square test.

RESULTS

The onset of sensory ( = 0.032) and motor block ( = 0.026) was earlier in Group LB2 than in Group LB1. The duration of analgesia was significantly prolonged in Group LB2 (643.55 ± 131.6 vs. 511.73 ± 128.6 min; = 0.001). The incidence of sedation was observed in more number of patients in Group LB2 ( = 0.01). Furthermore, the incidence of nausea, vomiting, and pruritus were observed in more number of patients in Group LB2 ( < 0.05).

CONCLUSION

Higher dose of butorphanol in brachial plexus block hastens the onset and prolongs the duration of sensorimotor blockade and analgesia but is associated with a higher incidence of sedation which requires intense monitoring.