A study published in the January issue of the journal Anesthesiology offers convincing evidence that even small decreases in body temperature during surgery increase blood loss significantly.
The good news here is that anesthesiologists the physicians responsible for monitoring patients’ vital signs during surgery are able to control temperature easily, at low cost, and with virtually no risk to patients.
According to lead study author Daniel I. Sessler, M.D., Chairman of Cleveland Clinic’s Department of Outcomes Research, all anesthetics interfere with the systems that naturally regulate body temperature. Consequently, body temperature decreases in surgical patients who are not actively warmed. Hypothermia (decreased body temperature) has long been known to increase the risk of heart attacks adverse myocardial events and infection, and prolongs recovery from surgery.
Past studies of the correlation between hypothermia and blood loss have offered conflicting results. Dr. Sessler’s study analyzed the results of every applicable study on hypothermia and blood loss from 1966 to 2006.
“When all the studies were evaluated together, the results clearly show that even very mild hypothermia increases blood loss and transfusion requirements by clinically important amounts,” Dr. Sessler said.
The results of his study come at a time when recent evidence is revealing that blood transfusions may present more risks than previously thought, and the study demonstrates that one simple way to reduce those risks is to reduce the need for transfusion by preventing a decrease in body temperature.
There still are circumstances in which induced hypothermia is necessary, Dr. Sessler said.
“In occasional patients, mostly those at risk for brain injury, hypothermia is perfectly appropriate,” Dr. Sessler said. “In these patients, physicians need to trade off the potential benefits and risks and choose the optimal approach for each individual.”
Founded in 1905, the American Society of Anesthesiologists is an educational, research and scientific association with 43,000 members organized to raise and maintain the standards of the medical practice of anesthesiology and improve the care of the patient.
American Society of Anesthesiologists (ASA)
520 N. Northwest Hwy.
Park Ridge, IL 60068-2573
United States
ASAhq