New Treatment for Severe Frostbite Shows Promise
May 2008A new treatment for severe frostbite is showing promise for saving fingers, toes, and limbs. Using an X-ray exam of arteries and veins to determine which lack blood flow and then deliver drugs via catheter, doctors are reopening recently frozen arteries with clot-busting and anti-spasmodic drugs. This treatment was significantly successful in preventing amputation, according to a study released in March at the Society of Interventional Radiology’s 33rd Annual Scientific Meeting.
“Previously, severe frostbite was a one-way route to limb loss,” said George R. Edmonson, M.D., interventional radiologist with St. Paul Radiology in St. Paul, Minn. “This treatment is a significant improvement. We’re opening arteries that are blocked so that tissues can heal and limbs can be salvaged. We were able to reopen even the smallest arteries, saving patients’ fingers and toes.”
One issue with severe frostbite is that small clots may form in the blood vessels, thus worsening the flow of blood.
“For half our patients who received the clot-busting drug Tenectaplase, this technique worked beautifully, saving all fingers, hands, toes and feet that otherwise would have been lost,” said Edmonson, who has been treating an average of six to 10 frostbite patients each year for the past 10 years. “Overall, in about 80 percent of the cases, it significantly improved patients’ outcomes.”
Edmonson and other doctors noted that expanded trials are needed to confirm the treatment’s effectiveness.
In a similar small study, reported last June in Archives of Surgery, University of Utah researchers looked at the possibility of using tissue plasminogen activator (tPA), a drug usually used to treat clots and stroke, for aiding in frostbite cases. Six patients with frostbite who had abnormal blood flow in the affected area were given tPA within 24 hours of getting the frostbite. The team compared these patients' outcomes to 25 frostbitten patients treated without tPA, plus one patient who received tPA more than 24 hours after the injury. The Utah team found that, among the six patients who received tPA within 24 hours, about 10 percent of the affected fingers or toes required amputation, compared with more than 40 percent among people who did not receive the drug. In addition, none of the tPA-treated patients had to have part of an arm or leg amputated, while there were 14 amputations among the untreated patients.
The doctors believe that tPA stops clotting stimulated by inflammation when frostbitten tissue is rewarmed, which in turn blocks blood vessesls and causes cells to die.