This age old myth has been taught over the generations, handed down from from medical eminence to medical students & junior doctors alike. Having been told the same thing recently by a resident in plastics, I thought I would attempt to debunk it here.
Where it Came From
Several publications of case reports in the 1940s cited digital nerve blocks with epinephrine as a cause for gangrene of the finger in the post-op period. This was further propagated in the surgical texts of the day (see references below).
It is widely accepted now (including by the authors) that the actual cause of the gangrene was thermal injury secondary to boiling hot soaks in boric acid solution post-operatively, which was recommneded practice back in the day.
Numerous reviews have examnied this - most recently this study by Chowdhry et al in the December 2010 edition of the journal of Plastic and Reconstructive Surgery :
Epinephrine in digital blocks has been condemned by traditional medical theory. The authors provide a retrospective review of 1111 cases involving digital block anesthesia with epinephrine in conjunction with an extensive literature review.
The authors conducted a retrospective review of 1111 cases involving digital and hand surgery. Observations were made concerning the location of and indication for surgery, age, sex, type of block used, type and dose of anesthetic, use of epinephrine and concentration, use of a tourniquet, follow-up, and complications. Dorsal and transthecal techniques were used exclusively. Patients with vascular compromise did not receive epinephrine and were excluded from the study.
One thousand one hundred eleven cases were reviewed, distributed among 692 male patients and 419 female patients. Sites of surgery ranged throughout the hand and all fingers for a variety of indications. Five hundred patients received injections of 1% plain lidocaine with a dosage range of 2 to 10 cc and an average of 5.7 cc. Six hundred eleven patients received injections of 1% lidocaine with epinephrine (1:100,000) in a dose range of 0.5 to 10 cc and an average dose of 4.33 cc. Nine hundred eighty-six patients (88.75 percent) followed up in the clinic. No patients suffered from digital gangrene in the epinephrine group.
After reviewing 1111 cases, there were no complications associated with the use of epinephrine in digital blocks. The authors suggest that correct application of epinephrine in digital blocks is appropriate, and defend its use.
The following caveats apply:
- digital blocks may be contraindicated in patients with disease processes involving the digital vessels at the base of the proximal phalanx
- adrenaline / epinephrine should be used cautiously in patients wth known cardiac disease, hypertension & peripheral vascular disease.
Kaufman, P. A. Gangrene following digital nerve block anesthesia. Arch. Surg. 42: 929, 1941.
McLaughlin, C. W., Jr. Postoperative gangrene of the finger following digital nerve block anesthesia. Am. J. Surg. 55: 588, 1942.
O’Neill, E. E., and Byrne, J. J. Gangrene of the finger following digital nerve block. Am. J. Surg. 64: 80, 1944.
Bunnell, S. Surgery of the Hand, 1st Ed. London: Lippin- cott, 1944. Pp. 100–105.