Representatives from ASHRAE, the Centers for Medicare & Medicaid Services (CMS), Food and Drug Administration (FDA), and The Joint Commission were among those who gathered at the Association for the Advancement of Medical Instrumentation (AAMI) headquarters on Oct. 23 to discuss the challenges associated with maintaining lower humidity rates in the operating room (OR).
Using a systems approach, meeting participants, who also included representatives from the American Hospital Association, Association of periOperative Registered Nurses (AORN), and AAMI standards committees, discussed a host of issues, such as the effects of the humidity level on product sterility.
“Our common goal is to work together to achieve the strong desire of healthcare delivery organizations (HDOs) to safely lower minimum humidity levels in the OR to 20 percent without risking compliance, functionality or patient safety issues with medical equipment and supplies,” says Mary Logan, president of AAMI.
The objectives of the meeting were to develop a shared understanding of the different perspectives and challenges of lowering humidity levels in the OR, promote joint strategies for addressing these challenges, and foster a common set of communication points and tips to help HDOs easily assess whether humidity levels can be safely lowered from both a compliance and patient safety perspective.
The meeting comes after CMS issued a categorical waiver of the Life Safety Code in April 2013 that would allow the anesthetizing locations of HDOs to operate with a relative humidity (RH) of equal to or greater than 20 percent, rather than the previous requirement of equal to or greater than 35 percent. The upper limit remained at 60 percent. The range mirrored a new national standard set by ASHRAE, which helps develop standards in the building industry.
Organizations must declare that they have elected to use the waiver at the beginning a CMS-conducted survey. CMS also requires HDOs to demonstrate compliance with the ASHRAE standard by documenting the range at which humidity levels are kept.
Not all stakeholders agree that the lower level is appropriate for certain devices used in the OR. Complicating matters is that one HDO already has been cited for applying a humidity level that was lower than that specified in the instructions for use (IFUs) for certain products used in the OR. The citation caught some in the healthcare community by surprise. In general, the medical device and supplies industry was unaware that humidity levels were being lowered in ORs until the California situation was brought to AAMI’s attention.
“This meeting was convened to prevent potential chaos in the field and help HDOs avoid being cited when they believe they are following the rules,” Logan says.
Shifting to a wider threshold that allows a minimum RH of 20 percent could mean substantial energy and cost savings for HDOs-especially those located in cold or dry climates-as it takes seasonal variations in humidity into account.
While containing costs is important, attendees agreed that delivering safe and effective patient care is paramount. Keeping RH in an acceptable range is crucial to delivering care; a level that is too high can result in damp supplies and increase the potential for mold growth, whereas a level that is too low can result in electrostatic discharge and affect sterility and maintenance.
Representatives from sterile supplies manufacturers emphasized that biological and chemical indicators (BIs and CIs) used to monitor the sterilization process require the humidity level to be at least 30 percent. If the humidity level were lower, the shelf life and proper functioning of these indicators could be compromised. They noted that RH and temperature must be controlled if BIs and CIs are to be used properly in the sterilization process.
Another issue is the integrity of product packaging, which requires a minimum level of 30 percent. Changing product packaging to withstand lower humidity would require major investments in time and money, as manufacturers would need to revisit product design and testing, revise their IFUs, and seek an FDA approval, they said.
Several participants expressed concerns about other supplies and medical devices that are used in the OR. Electrodes, for example, are sensitive to humidity, as are other devices with sensors. In addition, a vast array of electro-medical devices, especially ones that contain electronics, could malfunction as a result of the lower humidity level.
Furthermore, a large number of legacy medical devices still are in use at HDOs. Unlike many new products coming to the market, these items have not been tested in the lower humidity range. Devices with temperature controls or electronics are particularly sensitive to humidity.
Meeting attendees will work with AAMI on a set of communication points and tips that, once completed, will be shared by the participating organizations. In the meantime, HDOs that want to lower the humidity levels in the OR need to review the IFUs on all supplies and equipment used in this space, because it’s likely that many items call for humidity levels of at least 30 percent.
Source: AAMI
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