Recent Studies Reject Idea That Bouffant Caps Are Better At Preventing Infection
Organizations representing surgeons, anesthesiologists and nurses will gather in early 2018 to review evidence on the controversial issue of operating room attire, after a series of recent studies showed bouffant caps do not appear to be associated with a reduced risk for surgical site infections compared with traditional surgical caps.
“We are going to reconvene an evidence-based review process sometime after the first of the year to try to come to consensus,” said David B. Hoyt, MD, executive director of the American College of Surgeons.
“There’s been a disagreement about the literature. We’re going to try to get people to review it together and come to a consensus. There’s been new literature added … that will enrich that discussion, but it’s too early to say what will come out of it.”
Representatives of the Association of periOperative Registered Nurses said they have not received a formal proposal from the ACS.
However, AORN does plan to update its guideline on surgical attire next year. In light of the new research, the organization will begin its review of the literature in January, said Lisa Spruce, RN, DNP, director of evidence-based perioperative practice at AORN.
The organization typically updates its guidelines every three to five years. Its most recent guideline was published in 2016 following a 2014 literature review.
“We do think that enough [evidence] has been coming out that we will start looking at this guideline again in 2018.”
New recommendations could be available electronically halfway through next year, she said.
AORN will review the literature before deciding whether to change its stance that operating room staff must cover hair, ears and the nape of the neck. In the 2012 and 2016 versions of its guideline, AORN cited studies that concluded hair can be a source of bacterial organisms and highlighted outbreaks of postoperative wound infections that were linked to personnel carrying Staphylococcus aureusin their hair.
AORN’s guidelines have influenced both Centers for Medicare & Medicaid Services and the Joint Commission, which have given citations to hospitals where OR staff do not fully cover their hair and ears. As a result, many hospitals no longer permit use of traditional surgical caps in the OR to the frustration of many surgeons.
Between 2012 and 2014, AORN advocated banning the surgical cap and promoted bouffant-style hats instead. In its 2016 guideline, AORN does not specifically oppose the surgical cap but advocates head attire that covers all hair and the ears.
Representatives of AORN say this is not to prohibit use of the cap. “I have seen skullcaps do a perfectly fine job of covering the ears, as long as it’s not folded upwards,” Dr. Spruce said.
Last year, the ACS issued a statement on appropriate attire for surgeons, both in the OR and interacting with the public outside. It states that surgeons should cover their mouth, nose and hair during invasive procedures, but notes “there is no evidence that leaving ears, a limited amount of hair on the nape of the neck or a modest sideburn uncovered contributes to wound infections.”
Recent studies suggest bouffant-style caps do not reduce the risk for SSIs compared with other caps.
Among the studies presented at the ACS Clinical Congress, one showed cloth skullcaps were more effective than bouffant-style disposable caps at preventing airborne contamination in the OR.
Researchers tested three common styles of commercially available surgical headwear: disposable bouffant hats, disposable skullcaps with paper sides, and home-laundered and reusable cloth skullcaps. Airborne contamination testing was done in an OR as a team performed a one-hour mock operation that included gowning and gloving, passing surgical instruments, leaving and re-entering the OR, and performing electrocautery on a piece of raw steak to generate particles that were discharged into the air. Each hat style underwent testing four times, twice at each of the two different hospitals.
During the mock operations, bouffant hats and disposable surgical skullcaps had similar airborne particle counts. However, cloth skullcaps, which do not have a porous crown like their disposable counterparts, outperformed the bouffant hats, showing lower particle counts and significantly less microbial shedding at the sterile field.
The researchers also tested the fabric of each hat style for airflow, permeability and porosity. The analysis revealed that the bouffant hats had greater permeability than either type of skullcap.
“Some organizations and hospitals have suggested that all OR personnel wear disposable bouffant-type hats, but we found no apparent infection-control reason to disallow disposable skullcaps in the OR,” said lead author Troy A. Markel, MD, assistant professor of pediatric surgery at Riley Hospital for Children at Indiana University Health, in Indianapolis, in a statement.
The results have the potential to influence the OR attire policies of hospitals and health care regulatory bodies, he said.
“Based on these experiments, surgeons should be allowed to wear either a bouffant hat or a skullcap, although cloth skullcaps are the thickest and have the lowest permeability of the three types we tested.”
Two other studies presented at the ACS Clinical Congress examined the effect of surgeons’ headwear on SSIs in patients who’d undergone surgery.
Researchers from the University of Rochester analyzed SSI rates at two tertiary care teaching hospitals that had imposed strict regulations on OR attire in 2015. Although the policies were similar at the two institutions, one of the two hospitals was more stringent in its regulation of these policies. The researchers studied SSI rates for nine-month periods before and after the policy change at each hospital.
With the new policy in place, SSI rates increased from 0.7% to 0.8% at the hospital with a more stringent approach to OR attire. There was no change in infection rates at the hospital with a more lenient approach. Overall, the investigators concluded that a surgeon’s choice of cap did not harm patients.
“After a year with rigorous implementation of this widely unpopular measure, there was no reduction in SSIs at the two hospitals,” said the study’s senior author Jacob Moalem, MD, associate professor at the University of Rochester Medical Center, in New York.
The factors that predicted a high SSI rate included preoperative infection, operative time, an open wound, a contaminated wound and surgery at the hospital that had the more rigorous approach to OR attire.
As a result of the study, the hospitals have revised their policies, allowing for the wearing of skullcaps as long as the majority of hair is covered, Dr. Moalem noted.
He said the recent studies should settle any concerns about skullcaps as a potential risk factor for infection.
“This intervention is so unpopular with surgeons, and in certain circumstances is physically uncomfortable (such as when wearing loupes is required, for example), that I think the distractions caused by these restrictions are far more likely to contribute to harm to the patients than they are to help.”
Shanu N. Kothari, MD, a minimally invasive and bariatric surgeon at Gundersen Health System, in La Crosse, Wis., and his colleagues reanalyzed data collected during a single-center, randomized, prospective trial conducted between 2009 and 2015. In the trial, 1,543 patients were randomly assigned to having hair left on their abdomen or having their hair clipped; the investigators concluded that having hair left had no effect on SSI rates. Two certified nurses independently assessed every wound in the trial.
When investigators returned to the data to look for any effects of surgeon headwear, they found SSIs occurred more commonly among patients where the attending surgeon of record wore a bouffant cap compared with a skullcap, at a rate of 8.1% to 5%.
In an interview, Dr. Kothari said he believes personal preference and comfort should be the driving force on choice of OR headwear.
“Personally, I believe the culmination of all these studies on this topic has definitively answered the question that compliance with the current AORN OR attire policy does not impact SSI rates,” he said.
A study from the Texas Alliance for Surgical Quality Collaborative Project, published online in JAMA (2017; in press), showed no correlation of OR attire with SSI rates at 20 hospitals.
Dr. Spruce noted that AORN’s guidelines meet the criteria of the National Guideline Clearinghouse, a publicly available database produced by the Agency for Healthcare Research and Quality, in partnership with the American Medical Association and the American Association of Health Plans. To meet those criteria, AORN’s guideline writers must consider benefits and harm to patients, she said.
“We think we have enough evidence to say we feel like our patients are at increased risk when they are being exposed to health care workers’ hair and skin. In order to decrease that risk, no matter how small, it’s up to us to decrease our risk and keep our patients safe.”