Study: Contamination Increased 2000x With Bair Hugger Warming

Share Article

The heat from Bair Hugger patient warming creates a vortex that captures particles from below the surgical table, depositing them on the surgical site, according to a recently published study. 2,000 times more contaminant particles were found in the air over the wound with Bair Hugger warming than with air-free HotDog conductive warming.

With Bair Hugger warming, the particle count was 2,174,000 per cubic meter, an increase of 217,300%.

The use of Bair Hugger forced-air warmers during surgery creates convection currents that capture particles below the surgical table, lifting them into the sterile surgical field, according to research recently published by orthopedic surgeons. The waste heat radiating through the surgical drape induced the formation of tornado-like vortexes of rapidly spinning air near the surgical site. The vortexes sucked contaminated air from the operating room floor and deposited it over the surgical wound.

2,000 times more contaminant particles were found in the air over the wound with Bair Hugger warming than with air-free HotDog conductive warming. With HotDog patient warming, only 1,000 particles per cubic meter of air were present. With Bair Hugger warming, the particle count was 2,174,000 per cubic meter, an increase of 217,300%.

Concerned by convection currents produced by hot-air warming devices, orthopedic surgeons A.J. Legg and A.J. Hamer from Northern General Hospital in Sheffield, United Kingdom, compared the torso-style disposable blankets of 3M’s Bair Hugger system with the reusable, air-free HotDog conductive warming system. The surgeons released particles below the surgical table and then measured how many were transported to the surgical site. Neither surgeon has any financial relationship with either of the products studied.

The study was published in the February issue of The Bone and Joint Journal and entitled “Forced-air patient warming blankets disrupt unidirectional airflow.”

Dr. Scott Augustine, inventor of both products studied, stated, “Such a massive increase in airborne contamination is obviously a safety issue in contamination-sensitive surgeries. In joint replacement surgery, for example, a single airborne bacterium can cause a deep joint infection.”

Periprosethetic joint infections are often catastrophic: immense pain and suffering, permanent disability and an enormous cost to the hospital.

“Every joint infection is a disaster—both for the patient and the system,” said Dr. Augustine. “The process is horrific: ex-plant the joint, prolonged hospitalization, 6-8 weeks of IV antibiotics and then—assuming no amputation—re-implant the joint. The average cost is around $100,000.” More than 12,000 of these infections occur each year in the US, a rate that some see as a significant public health problem.

A study conducted by other orthopedic surgeons and published in November 2011 in the Journal of Bone & Joint Surgery positively linked Bair Hugger warming to increased joint replacement infections. The surgeons showed that their deep joint infection rate dropped 74% when Bair Hugger warming was discontinued.

“While Bair Hugger has served most surgical patients well for the past 25 years,” said Dr. Augustine, “these two studies along with three others recently published clearly show that hot-air warming has unintended consequences and should never be used during total joint replacement surgery. Contamination of the sterile surgical field is a serious risk to patient safety.”

The BJJ article follows several other recently published, peer-reviewed studies in the Journal of Bone & Joint Surgery (Br), the American Journal of Infection Control, Anaesthesia, Orthopedic Review and Anaesthesia & Analgesia relating to the potential contamination of surgical sites by forced-air warming devices.

The BJJ study may be found at;95-B/3/407&related-urls=yes&legid=jbjsbr;95-B/3/407.

Citations to other studies mentioned in this article:

Albrecht M, Leaper D et al. Forced-air warming blowers: An evaluation of filtration adequacy and airborne contamination emissions in the operating room. Am J Infect Control 2011;39:321-8.

Leaper D et al. Forced-air warming: a source of airborne contamination in the operating room? Orthopedic Rev. 2009;1(2):e28.

McGovern et al. Forced-air warming and ultra-clean ventilation do not mix. J Bone and Joint Surg-Br. 2011;93(11):1537-1544.

Legg et al. Do forced air patient-warming devices disrupt unidirectional downward airflow? J Bone and Joint Surg-Br. 2012;94-B:254-6.

Belani et al. Patient warming excess heat: The effects on orthopedic operating room ventilation     performance. Anesthesia & Analgesia July 2012 (prepublished online).

Dasari et al. Effect of forced air warming on the performance of operating theatre laminar flow ventilation. Anaesthesia 2012;67:244-249.

About HotDog® Patient Warming
The HotDog patient warming system is a state-of-the-art, conductive fabric temperature management solution that prevents and treats perioperative hypothermia. Used in some of the most prestigious hospitals in the world, HotDog patient warming is an air-free system that is effective and safe even in ultra-clean surgeries.

Dr. Scott Augustine invented the patient warming field, when he pioneered forced-air warming 25 years ago. Since then, hundreds of millions of patients have received the benefits of normothermia during surgery. Due to concerns with patient safety in ultra-clean surgeries, Dr. Augustine and his team of engineers sought to create an alternative warming solution to meet the needs of the healthcare community. HotDog is produced by Augustine Temperature Management.

Share article on social media or email:

View article via:

Pdf Print

Contact Author

Susan Schaefer
Email >