Optimal Time Delay of Epinephrine in One-Per-Mil Solution to Visualize Operation Field.

BACKGROUND

This study aimed to find out the optimal time delay of epinephrine in one-per-mil tumescent solution containing 1:1,000,000 epinephrine and 0.2% lidocaine to achieve optimal visualization in hand surgery.

MATERIALS AND METHODS

Twelve healthy male subjects who volunteered to join this prospective, randomized, double blind study were selected with convenient sampling technique. The subject's hand and the solution, either the one-per-mil or normal saline solution, were randomly selected. Injections were given to the ring finger's pulp, whereas the oxygen saturation (SpO) of each finger was measured with Masimo's Radical-7 Pulse Oximeter at 5 min before injection and continuously up to 45 min after injection. The device showed the SpO every 2 s. Any value of SpO was noted if it stayed the same point for at least 30 s in a row without interruption. The time of the lowest SpO was recorded and analyzed.

RESULTS

The average of SpO after injection in the epinephrine group was 96.5 (95-97), P = 0.002, whereas the normal saline group was 97.5 ± 1.168, P = 0.003. Both were statistically significant compared with their respective baseline values. The average delta SpO of the epinephrine group was 3.42 ± 0.996, whereas the normal saline group was 1.50 ± 1.567 (P = 0.001; CI 0.923-2.911). The time to achieve the lowest SpO in the epinephrine group was obtained at the average time of 13.90 ± 5.38 min after injection.

CONCLUSIONS

The optimal time delay of the epinephrine in the one-per-mil tumescent solution was 13.90 ± 5.38 min after injection.