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Evidence Growing Against Safety of Forced-air Patient Warming

Yet another peer-reviewed study—the third in the past five months—has been published showing that forced-air patient warming generates convection current activity in the vicinity of the surgical site, which could lead to contamination of the sterile field. The study, published by Dr. Kiran Dasari in the March issue of Anaesthesia, is more evidence that a significant patient safety issue exists.  Surgeries with implanted foreign materials, like hip and knee replacements, could be greatly compromised depending on the type of warming technology used. The researchers investigated whether the floor-to-ceiling temperatures around a draped manikin in a laminar-flow theatre differed when using forced-air [...]

Another Study Shows the Risks of Using Forced-air Patient Warming

Researchers in the UK published a study in the February, 2012, issue of the Journal of Bone and Joint Surgery-Brexamining the effects of forced-air warming on operating room airflow and surgical site sterility. Summary: “Forced-air warming resulted in a significant mean increase in the temperature (1.1°C vs 0.4°C, p<0.0001) and number of particles (1038.2 vs 224.8, p=0.0087) over the surgical site when compared with [HotDog®] warming, which raises concern as bacteria are known to require particles for transport.” Methods: The researchers studied the temperature and the number of particles over the surgical site comparing forced-air warming (Bair Hugger®), radiant warming (HotDog), [...]

Study Links Forced-air Warming to Infections: 3.8x Increase In Orthopedic Implant Cases

Previously, research studying the effects of forced-air warming on laminar flow operating theaters was limited to contamination…until now. The use of forced-air warming during orthopedic implant surgery was associated with a 3.8 times increase in deep joint infections as compared to warming patients without forced-air, according to a newly published study. The study, published in the November issue of the Journal of Bone and Joint Surgery (Br), was conducted by orthopedic surgeons at Northumbria Healthcare Trust in the United Kingdom. Reviewing hip replacement surgeries performed on 1,437 patients over 2.5 years, the study compared the incidence of deep joint infections on patients warmed [...]

FAW’s Impact on SSIs

“How can forced-air warming be unsafe when research shows that it reduces infections?” This is a common question, and the best explanation was given by Yale scientist Dr. Marc Abreu in the October 2010 Anesthesiology News Review. In the article, titled New Concepts in Perioperative Temperature Management: Monitoring and Management, Dr. Abreu wrote that, “…any potential airborne contamination caused by FAW waste heat must have a negligible effect on soft tissue SSIs. However, patients undergoing surgery involving implanted foreign materials, especially for orthopedics, may be at higher risk for infection from airborne contamination.” (emphasis added) The risk of infection with FAW, at least as established [...]

Latest Evidence of Forced-Air Contamination — Must See

Here is the latest evidence of forced-air warming units contaminating the operating room by overcoming protective laminar flow ventilation. The room temperature tracer particles and bubbles are neutrally buoyant, which is to say they follow the air currents of the room. When forced-air warming units dump 900 watts of waste heat into the operating room, it is no surprise that we can visualize the effects: heat rises. Notice the laminar flow working properly with conductive fabric warming, or with forced-air "Heat OFF" as control. Then with "Heat ON" watch the stunning evidence of forced-air waste heat mobilizing air from the dirty floor [...]

By | February 15th, 2011|0 Comments

Laminar vs. Conventional Ventilation

Common Question: “My OR doesn’t use laminar flow. Does waste hot air still matter?” Answer: Absolutely. Consider the following: What is laminar ventilation and what is conventional ventilation? Operating room air is typically introduced from the ceiling, moves towards the floor, and exits through the side vents. US standards for hospital construction require that operating room ventilation be filtered, at a minimum, to an efficiency of >90% for the removal of germ sized particles. Many ventilation systems do much better than that, by employing High Efficiency Particulate Air filtration commonly known as HEPA, which by definition removes >99.97% of germ sized particles [...]