Optimal Time Delay of Epinephrine Injection With "One-per-mil" Tumescent Solution

Optimal Time Delay of Epinephrine Injection With "One-per-mil" Tumescent Solution to Visualize Operation Field in Hand Surgery Without Tourniquet

The aim of this study is to know the characteristic of "one-per-mil" tumescent solution in regards of the optimal time delay to achieve optimal visualization of operation field in hand and digit surgery. Hypothesis: Epinephine in "one-per-mil" concentration by tumescent injection technique will provide faster decrease in oxygen saturation compared to normal saline solution injected by tumescent technique. Epinephrine in "one-per-mil" concentration by tumescent injection technique will provide effectiveness in vasoconstriction longer than 10 minutes as the optimal time delay. Epinephine in "one-per-mil" concentration by tumescent injection technique causes no finger necrosis as normal saline solution injected by tumescent technique.

This is a prospective, randomized, double-blind study to measure the optimal time delay of 1:1,000,000 epinephrine in saline solution injected by tumescent technique until maximum vasocontriction in the distal finger is achieved. Subjects will be injected in both his ring fingers(distal phalanges, volar side) with randomized solutions, one containing "one-per-mil" tumescent solution and the other containing only normal saline solution; information which both the injector and examiner are blinded from. Maximum vasoconstriction of the finger injected is depicted by the lowest oxygen saturation (recorded every minute until 45 minutes using pulse oxymeter).

"One-per-mil" tumescent solution containing 1:1,000,000 epinephrine concentration in saline solution, is injected to the finger.

After being injected with the solution, the ring finger is put on a continuous monitoring of pulse oxymeter, while the examiner records the decrease of oxygen saturation every minute until 45 minutes length of time. The time when lowest oxygen saturation is achieved is recorded, depicting the optimal time delay to achieve maximum vasoconstriction of the finger after injection.

Pain sensation of the finger's pulp was examined (using VAS) and recorded every 15 minutes. These data will be compared to the baseline data prior to injection.

Tactile sensation of the finger's pulp was examined (using Semmes Weinstein Touch Test) and recorded every 15 minutes after the injection. We will compare this data with the baseline data collected prior to injection.

Subjects will be observed for 6 hours after the injection to record any sign and symptoms related to the complication of the procedure (persisted pain, pallor, numbness).

After injection, temperature of fingertip is measured and recorded every 15 minutes for total time of 45 minutes. The data will be compared with baseline temperature recorded before injection

Inclusion Criteria: Willing to join the research BMI 18.5-23 Healthy individual, no history of blood or coagulation disorders Exclusion Criteria: BMI <18.5 or >23 History of blood or coagulation disorder, diabetes mellitus, heavy smoker