Chapter 3 Safe Epinephrine in the Finger Means No Tourniquet

10.1055/b-0037-142174

Chapter 3 Safe Epinephrine in the Finger Means No Tourniquet

Donald H. Lalonde

THE RISE AND FALL OF THE MYTH OF THE DANGER OF INJECTING EPINEPHRINE IN THE FINGER

In the period before 1950, the belief developed among surgeons that epinephrine causes finger necrosis. This dogma became entrenched in medical school teachings, where we were told that we should not inject epinephrine into “fingers, nose, penis, and toes.” Evidence-based medicine has now altered that misconception. This chapter tells the story of how it happened.

Clip 3-1 History of the rise and fall of the epinephrine danger myth.

THE LONG HISTORY OF SAFE USE OF EPINEPHRINE IN THE FINGER BY CANADIAN SURGEONS

When I was a medical student at Queen′s University in Kingston, Ontario, from 1975 to 1979, there was an excellent hand surgeon, Dr. Pat Shoemaker, who used epinephrine in the finger all of the time. He did wide awake flexor tendon repair with field sterility in the emergency department and got good results. Some of his colleagues were skeptical and taught medical students the traditional view that epinephrine in the finger was dangerous and could cause finger necrosis as a result of vasoconstriction. Only Dr. Shoemaker was “allowed” to do it, because he was a hand surgeon who did not have trouble—“yet!” He never did get into trouble, and has long since retired and passed away.
Dr. Bob MacFarlane of London, Ontario, past president of the American Society for Surgery of the Hand, became famous for his Dupuytren′s research. He regularly performed wide awake Dupuytren′s surgery with lidocaine and epinephrine hemostasis.
Dr. John Fielding, the first plastic surgeon in Ottawa, pioneered use of wide awake hand surgery with epinephrine hemostasis in that city. Many Ottawa surgeons followed his lead and used the technique routinely long before I did.
Many other Canadian hand surgeons in other cities adopted the same technique.

Clip 3-2 How to reverse epinephrine vasoconstriction with phentolamine injection in the finger.

SIX THINGS STIMULATED MY INTEREST IN BEGINNING ROUTINE ELECTIVE EPINEPHRINE HEMOSTASIS USE IN THE FINGER FOR EVERY CASE IN 2001

I knew of well over 100 surgeon-years of clinical safety in the practices of Drs. Shoemaker, MacFarlane, Fielding, and others who routinely injected epinephrine in fingers. These were good surgeons. I trusted and respected their clinical judgment.
I knew I could use phentolamine as an epinephrine vasoconstriction rescue agent if I needed it.
I had been using epinephrine for carpal tunnel, flexor sheath ganglion, and trigger finger procedures for many years with no problems.
I had used epinephrine in the finger many times before 2001, but not routinely, and I had not encountered any problems.
We had great difficulty getting the main operating room for our hand trauma cases because of a chronic shortage of anesthesiologists in Saint John. Epinephrine hemostasis meant no tourniquet was required. It also meant we could operate on a patient with a traumatic hand injury outside the main operating room at our convenience, Monday through Friday, 9 to 5, without having to admit patients or wait for an anesthesiologist.
Dr. Keith Denkler published his landmark paper in 2001.1 Dr. Denkler painstakingly reviewed 120 years of literature from 1880 to 2000, most of it by hand through Index Medicus volumes, and did not find one case of lidocaine with epinephrine finger necrosis in the world literature. This was my tipping point. After reading his paper, I decided to use epinephrine in every finger with good capillary refill on fingertip pulp palpation until I needed phentolamine rescue.

FOUR MAIN CONCEPTS THAT SUPPORT THE FALL OF THE MYTH

We can reliably reverse epinephrine vasoconstriction with phentolamine in the human finger.2
There were no lost fingers and not one case required phentolamine rescue in a prospective study of 3110 consecutive cases of elective epinephrine injection in the finger and hand by nine surgeons in six cities, called the Dalhousie Project clinical phase. 3 A similar study of over 1111 fingers injected with epinephrine in 2010 by another group of surgeons yielded similar results.4
More than 100 cases of high-dose 1:1000 epinephrine5,6 revealed that not one finger injected with a dosage 100 times the concentration of epinephrine that we use clinically actually died. If 1:1000 epinephrine does not kill fingers, it is highly unlikely that 1:100,000 will ever kill a finger.
The source of the epinephrine myth, created between 1920 and 1945, stemmed from the use of procaine (Novocaine).7 It was the “new caine,” invented in 1903 to add to existing cocaine. It was the only safely injectable local anesthetic until the introduction of lidocaine in 1948. More fingers died from procaine injection alone than from procaine plus epinephrine injection. Procaine started with a pH of 3.6 and became more acidic as it sat on the shelf.8,9 The U.S. Food and Drug Administration (FDA) instituted mandatory expiration dates on injectable medicines in 1979.10 The “smoking gun” paper that established that procaine was the actual cause of finger deaths that had been blamed on epinephrine was a 1948 FDA warning published in the Journal of the American Medical Association that found batches of procaine with a pH of 1 destined for injection into humans!11

How to Reverse Epinephrine Vasoconstriction in the Human Finger With Phentolamine

I have now injected more than 2000 fingers with epinephrine. I have not needed phentolamine rescue once. I also have been treating patients with morphine for over 30 years and have not had to rescue one with naloxone. That does not mean I will not in the future, and I know how to use it if I need it.
I have demonstrated phentolamine rescue to many visiting surgeons. I recommend that all hand surgeons try it at least once. This will help them and their nursing colleagues dissolve their epinephrine fear.
What is phentolamine? Phentolamine is an alpha-adrenergic blocking agent introduced in 1957 as an antihypertensive agent in pheochromocytoma management.
Phentolamine manufacturers recommend a dosage of phentolamine of 5 mg intravenously to lower blood pressure.12 The dosage to reverse adrenaline vasoconstriction in the finger is to inject 1 mg of phentolamine in 1 ml or more of saline solution into the subcutaneous fat wherever there is severe epinephrine pallor in the skin. This small extravascular dose will not affect blood pressure. The finger will pink up within an hour or two.