Forced Air Warming Devices — Are They Dangerous?

Forced-air warming devices, which are used in most major surgeries, have recently become subject to intense scrutiny over alleged safety concerns. Several studies have linked their use to higher risks of infections—specifically major joint infections occurring after hip or knee operations.

Why do patients need to be warmed during surgery?

One of the most common complications that arises during surgery is that the patient can become hypothermic. When patients undergo anesthesia, they become incapable of regulating their body temperature naturally, which can drop a full 35 degrees within the first 30 minutes of surgery. Aside anesthesia, temperature drops may occur as a result of IV fluids or the cold environment of the operating room. Hypothermia can increase blood loss, the chance of infection and even raise mortality rates. Therefore, it is critical that patients remain warm during surgery.

The Centers for Medicare and Medicaid Services adopted a quality measure that mandated any patient who undergoes general or neuraxial anesthesia for procedures over 60 minutes must reach a temperature of 36 degrees Celsius. If for some reason this temperature is not achieved, it must be shown a proven active warming measures was used.

How are patients warmed during surgery?

Surgical warming blankets are used to fight the onset of hypothermia and raise the patient’s dropping body temperature. These blankets, however, must not raise the temperature of the operating room. Forced Air Warming (FAW) blankets are the most common method to achieve this.

FAW blankets carry warmed air through a hose to the blanket which is draped on and around the patient. It is this forced air that ultimately makes contact with the patient to heat the patient.

By far the most commonly used surgical warming device today is called the Bair Hugger. The Bair Hugger was developed in the 1980s for Arizant by Dr. Scott Augustine. It was revolutionary for its time, and is now used in over 90% of major surgeries in the US. In 2010, Arizant was acquired by 3M, who continues to manufacture the Bair Hugger today.

Are FAW blankets safe?

Although the Bair Hugger has performed the function of warming efficiently, other safety concerns have been studied recently and the blanket and manufacturer have come under controversy as the result of several major safety studies. It has been alleged that the use of the Bair Hugger in surgeries may contributed to over 12,000 cases of orthopedic implant infections each year by introducing bacteria into the surgical site.

The main danger of exposing the patient’s surgical site to contaminants have been joint infections. Joint infections (or Septic Arthritis) is the painful inflammation of the area around an affected joint as the body attempts to fight the bacterial, viral, or fungal infection. These infections can coincide with fever-like symptoms and develop into severe medical complications.

A synopsis of the ongoing research into FAW blanket dangers can be found here.

Current lawsuits against the Bair Hugger manufacturer, 3M, claim 3M was aware of the safety risk and attempted to discredit studies which showed the link between Bair Hugger’s use and patient’s exposure and contraction of joint infections.

Are there safe and effective alternatives to FAW blankets?

There are alternatives and some alternatives present a major improvement in safety when compared to forced air blankets. A study published in Bone & Joint Journal found that air circulating over the surgical wound in the forced-air warmer contains 2000x more contaminants than the exposure of available alternative systems.

Was a FAW blanket used in my operation?

Although most individuals are unaware of what occurred during their surgery or the devices employed due to anesthesia, it is highly likely that a forced-air warming blanket was used in your surgery.

If you recently had surgery and believe you are suffering from an infection, visit your doctor for a medical diagnosis. Infections spread quickly and delays will lead to complications and potential long-term health conditions.

If you or your doctor believe your joint infection was the result of a joint surgery (specifically hip or knee replacements or exploratory surgeries) you may be entitled to compensation for your injuries. Currently, major mass tort lawsuits are being filed against 3M on behalf of individuals who are have contracted infections during joint operations. Your time to file is limited, so if you or a loved one may have been affected, you should contact an attorney immediately.