From 1972 through September, 2002, when HEMS safety research by Dr. Ira Blumen of the University of Chicago Aeromedical Network (UCAN) was completed, HEMS had flown approximately three million hours, transporting some two and three-quarter million patients. In that time, there were 166 crashes involving HEMS, with 183 fatalities. The UCAN study found that while the number of crashes each year has fluctuated, the number per 100,000 patients flown had dropped from 17.36 in 1980 to 5.5 in 2001.
The risk to patients, estimated over the years of the study, is reported as a fatality rate of 0.76/100,000 patients. Subsequent admission to a hospital carries with it a greater risk of death from complications or errors: various recent estimates range from 1.2/100,000 patents to 292/100,000 patients.
Nonetheless, any form of medical transport incurs inherent risk and in the past few years there have been increased numbers of accidents associated with the increased number of helicopters and transports. In an editorial comment in the UCAN study, a past president of the National EMS Pilot Association emphasizes that the causes of crashes haven’t changed over the years. The top three causes are “risk taking, pre-flight planning, and in-flight decisionmaking,” reflecting the unique pressure placed on crews by the condition of the patient and by the feelings of obligation to fly.
The air ambulance service community has taken significant steps, particularly in the area of aircrew resource management (a proven airline industry safety tool) to improve its safety for patients. Some HEMS prograir ambulance service are replacing aircraft, hiring pilots to fly under Instrument Flight Rules (IFR), and employing new technologies such as night vision goggles (NVG’s) and terrain avoidance warning systems (TAWS), especially important when weather conditions abruptly change mid-mission.80 Transport medicine is among the most complex arenas of medicine, and is characterized by the need to provide immediate access to time-sensitive care for critically ill and injured patients at the same time that operations are conducted in hostile environmental conditions with limited planning time. As Justice Oliver Wendell Holmes once noted: “to be safe does not mean to be risk free.” Recognizing that risk cannot be completely eliminated, it is essential both for the public served, and the pilots, nurses, paramedics, physicians, and other health care providers who deliver care, that the practice environment be as safe as possible.
To that end, the Association of Air Medical Services has already initiated Vision Zero (http://aamsvisionzero.org/) and has joined the International Helicopter Safety Team (IHST, www.ihst.org), led by the American Helicopter Society (AHS), the Helicopter Association International (HAI), the Federal Aviation Administration (FAA), and Transport Canada to reduce helicopter accidents by 80% in the next ten years.
These initiatives seek more effective methods and approaches to avoiding errors in complex systems premised on the model that providers must work collaboratively, on a voluntary basis, with regulators to identify and accelerate the implementation of best practice standards. These efforts focus on developing and implementing strategies using cost benefit analysis and evidence based best practices related to safety in order to prioritize investment and financial plans to result in a goal of zero serious injuries or fatalities.
