Comparison of bupivacaine and lidocaine with epinephrine for digital nerve blocks

This study compared the efficacy in terms of pain of injection, time of onset and duration of action of digital blocks of bupivacaine 0.5% alone and lidocaine 1% with epinephrine (1:100,000).

A randomised double-blind prospective study was performed in a single self-controlled group of 12 healthy volunteers (4 women, 8 men). Each participant was randomised to receive either lidocaine 1% with epinephrine (1:100,000) or bupivacaine 0.5% in either the right or left middle finger. Pain of injection was measured as the primary outcome using a 0-100 mm visual analogue scale. The time before anaesthesia to pinpricks was recorded and the duration of anaesthesia was reported by all volunteers. Statistical analysis was conducted using the non-parametric Wilcoxon signed rank test.

Median visual analogue scale scores were significantly different between the lidocaine + epinephrine and bupivacaine groups (26.00 mm (4-52) vs 40.50 mm (10-71), p<0.05). The median time before anaesthesia to pinpricks was not significantly different between the two drugs (3.45 min (3-8) vs 3.30 min (3-8), p = 0.84). The median time needed for return of pinpricks was significantly different between the two drugs (321 min (228-463) vs 701 min (245-913), p<0.05). Follow-up was completed at 24 h.

Lidocaine (1%) with epinephrine (1:100 000) was significantly less painful and had a shorter duration of action than bupivacaine (0.5%), which had a similar onset of action for digital nerve block.

ISRCTN45121950.