Decreasing the pain of finger block injection: level II evidence

There is level II evidence that volunteers prefer the single subcutaneous injection in the midline of the proximal phalanx with lidocaine and epinephrine (SIMPLE) finger block over the classic two dorsal injection block technique. The purpose of this study was to possibly further decrease the pain of digital block injection by examining the effect of the duration of injection on the pain felt by volunteers receiving the SIMPLE block at two different injection rates.

Forty healthy blinded volunteers were injected 2 mL of lidocaine 1 % and epinephrine 1/100,000 in the digital palmar crease of both long fingers, one at a time. Two different rates of injection were used: 8 and 60 s. Pain scores were measured using a visual analogue scale and the volunteers were asked which of injection techniques they preferred.

The visual analogue scale results revealed less pain with the slow injection (p < 0.001). Thirty three out of 40 volunteers preferred the slow injection rate. No difference could be attributed to sex of participants or to the first hand injected.

Blinded volunteers preferred digital blocks injected over 60 s to the more rapid 8 s. Decreasing the pain of injection only takes a minute of our valuable time for finger blocks.