Epinephrine in digital block: color Doppler flow imaging.
BACKGROUND
Epinephrine is currently added to local anesthetics for its advantageous vasoconstrictive effects. Traditionally, however, its use is not advised for digital block anesthesia due to the risk of digital gangrene.


OBJECTIVE
To observe vasoconstrictive effect of epinephrine in digital block anesthesia.


METHODS
Digital blocking with epinephrine containing lidocaine was performed in 24 subjects undergoing surgical procedure of their finger and toes. Digital artery blood flows were studied with color Doppler ultrasonography before digital blocking and at 10th, 60th, and if needed 90th minutes after blocking. Doppler parameters such as peak systolic velocity, end diastolic velocity, and resistive index values were studied.


RESULTS
There were statistically significant decrease of blood flow rates and an increase of resistive index in all patients within 10 minutes. At the 10th minute of digital block, four patients had no measurable blood flow, which was restored within 60 or 90 minutes. Others showed diminished but persistent blood flow, which returned to normal within 60 minutes. No systemic or local complication related with epinephrine usage was observed.


CONCLUSIONS
Vasoconstrictive effect of epinephrine in local anesthetics is not persistent and resolves within 60 or 90 minutes. Its use seems to be safe in selected patients.
Altinyazar
H Cevdet
HC
Department of Dermatology, Zonguldak Karaelmas University, Faculty of Medicine, 67600 Zonguldak, Turkey. antinyazar@karaelmas.edu.tr
Ozdemir
Hüseyin
H
Koca
Rafet
R
Hoşnuter
Mübin
M
Demirel
Cengiz Bekir
CB
Gündoğdu
Sadi
S
D000328:Adult; D000772:Anesthesia, Local; D004837:Epinephrine / Q000494:pharmacology*; D005260:Female; D005385:Fingers / Q000098:blood supply* / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D012039:Regional Blood Flow / Q000187:drug effects; D014034:Toes / Q000098:blood supply* / Q000000981:diagnostic imaging; D018615:Ultrasonography, Doppler, Color; D014661:Vasoconstriction / Q000187:drug effects; D014662:Vasoconstrictor Agents / Q000494:pharmacology*
D014662:Vasoconstrictor Agents; D004837:Epinephrine