Warming device speeds recovery.

A new warming device could cut from hours to minutes the time patients need to recover from the body-chilling effects of anesthesia, Stanford (Calif.) University researchers suggest. It also may help them avoid surgical wound infections associated with recovery and have uses outside the operating room in cases of hypothermia, or abnormally low body temperature, points out Dennis A. Grahn, a senior research scientist in the Department of Biological Sciences. "For instance, emergency medical crews might use this type of device at the site of a mountain rescue."

Recovery from anesthesia generally is uncomfortable, lengthy, and in some cases unhealthy. This is because the body's temperature-regulating mechanisms shut down when a person is anesthetized. After surgery, the anesthetic wears off in a matter of minutes. but it can take hours for temperature to return to a level that can be governed by the body's normal mechanisms. That transition usually is accompanied by prolonged shivering and blood vessel constriction. An increased incidence of surgical wound infection has been associated with postoperative blood vessel constriction because of decreased circulation to the tissues.

One way of avoiding the shivering and related reactions has been to maintain body temperature throughout surgery. Even when this is done, shivering and vessel constriction still occur in about 25% of patients because the body's temperature-regulating system...