New Normothermia Research Results in Familiar Findings

Published on: 

Patient warming methods seem to come and go, but in the process of trying to prove their worth, they inevitably compare themselves to forced-air warminga technology found in more than 80 percent of U.S. hospitals and long considered to be the industrys gold standard.

These comparisons became even more important to manufacturers of competitive warming systems when the Centers for Medicare and Medicaid Services (CMS) updated its normothermia quality measure, known as SCIPInfection-10, which mandates effective warming for anesthetized patients undergoing surgical procedures one hour or longer in duration.

The updated measure became effective for Oct. 1 discharges and includes new language that extends the definition of active warming devices to include conductive warming into the mix of forced-air warming, warmwater garments and resistive warming. When first issued in July 2009, the measure limited active warming methods to forced-air warming and warm-water garments.

As more products enter the patient warming market, they often seek to compare themselves to forced-air warming. As a result, Bair Hugger® therapy and the Bair Paws® system have recently been examined in a number of independent, comparative clinical studies.(1-6) These study results were presented during the 2010 ASA annual meeting in San Diego and further support a wealth of existing research that demonstrates the enhanced temperature management performance of forced-air warming when compared to other modalities.

Among the key findings from these abstracts:

- Bair Hugger therapy is an effective method of warming surgical patients.(1-7)


- A Full Body Bair Hugger blanket rewarmed patients two times faster than a resistive-electric full body warming blanket following major maxillary tumor surgery.(4)

- Patients warmed with resistive-electric blankets did not reach a normothermic temperature after being warmed for four hours.(4)

- The Bair Hugger Full Access Underbody blanket resulted in significantly warmer core temperature than the use of a resistive-electric mattress or no warming in post-cardiac bypass periods.(5)

- The Bair Paws system provides a significant gain in terms of temperature and thermal comfort during the perioperative period for patients undergoing elective surgery.(3)

This wider range of active patient warming modalities included in the SCIP-Inf-10 measure broadens the options available to hospitals, but comes up short in addressing the ultimate purpose of the measure, which is maintaining normothermia in patients undergoing surgery. In its current form, the measure asks hospitals to either document the use of active warming or record a body temperature of 36°C or higher near anesthesia end time. While the measure encourages the use of active patient warming, in its latest iteration it does not require the active warming modality to meet the 36°C benchmark. Allowing facilities to receive credit for the measure by simply employing an active warming modality may unintentionally undermine the goal of normothermia.

The recent change in SCIP-Inf-10 makes it more essential than ever for facilities to clearly understand the multiple options available and to be empowered with the correct tools to achieve the measures desired patient outcomes. The recent clinical abstracts presented at the ASA meeting further outline the performance gap between forced-air warming and other warming methods.

Forced-air warming meets the SCIP-Inf-10 measures goal of helping patients avoid unintended hypothermia and has been part of the active warming definition since its inception. The technologys 23-year track record of safety and efficacy is supported by its use with more than 125 million patients and over 100 published papers document its clinical benefits. It is the only warming modality with published clinical outcome data supporting effectiveness in normothermia maintenance, which helps reduce surgical site infections, and studies have found forced-air warming to be the most effective method in general for preventing and treating unintended hypothermia.(7)


1. Ouchi T, et al. Lithotomy Underbody Air Blanket Can Prevent Intraoperative Redistribution Hypothermia. ASA Abstracts 2010; A088.

2. Nguyen HH, et al. A New Underbody Resistive Warming Device vs. Forced-Air Warming to Prevent Perioperative Hypothermia. ASA Abstracts 2010; A087.

3. Gentile A, et al. Hypothermia Prevention: Assessment of a New Forced Warming Air Device. ASA Abstracts 2010; A080.

4. Plattner O, et al. Comparison of a Forced-Air and a Resistive Warming Device for Intraoperative Rewarming. ASA Abstracts 2010; A076.

5. Engelen S, et al. A Comparison of Under-Body Forced-Air and Resistive Heating During Hypothermic Bypass. ASA Abstracts 2010; A075.

6. Karnoski R, et al. Intraoperative Warming with vitalHEAT during Open Abdominal Surgery. ASA Abstracts 2010; A086.

7. Hooper V, et al. American Society of PeriAnesthesia Nurses Development Panel. Evidence-Based Clinical Practice Guideline for the Promotion of Perioperative

Normothermia. Journal of PeriAnesthesia Nursing. 2009; 24(5): 271-287.