Everything you ever wanted to know about operating room head coverings

In case you might want to challenge your hospital’s policy on the subject, I have gathered all of the recent research I could find on surgical head wear.

In response to a 2013 question from a reader, I blogged about the complete lack of evidence that OR staff hair caused wound infections or any other problem. After a similar question from another reader three years later, I pointed out nothing had changed.

Finally a 2017 paper in the journal Neurosurgery appeared online comparing the incidence of wound infections in clean cases for the 13 months before and the 13 months after the institution of a ban on the wearing of the traditional surgeons’ ca`p. Over 15,000 patients were included in the study which found no statistically significant difference in the rate of wound infections.

Another chapter in “Surgical Cap Wars”

No one expected the AORN [Association of periOperative Registered Nurses] to meekly accept the conclusion of the paper which found no difference in infection rates when surgeons wore surgical skullcaps or a bouffant-style head coverings.

The AORN recently fired back with a letter to Neurosurgery, the journal that published the paper. It has not yet printed the letter or a response to it by the authors of the paper. I look forward to seeing both.

Meanwhile, Becker’s Infection Control and Clinical Quality revealed some tidbits an article entitled and “AORN experts respond to study on bouffant use and SSI rates.” [SSI = surgical site infection]

The AORN claims that it never mandated the use of bouffant headgear. It merely called for “a clean surgical headcover or hood that confines all hair and completely covers the ears, scalp skin, sideburns, and nape of the neck should be worn” because “hair carries bacteria that could [emphasis mine] cause an SSI.”

Lisa Spruce, the director of evidence-based practice for the AORN, said, “It’s up to the facility to determine what’s the best way to get everyone’s hair covered.” This is rather disingenuous as everyone knows the only way to cover every single hair on the head is to wear a bouffant or a hood.

The AORN did not offer any evidence that hair causes infections. Instead Spruce and the other AORN experts chose to nitpick the Neurosurgery study by pointing out a single scatter plot that showed what they said was a decrease in SSI rates after bouffants were worn.

They claim the figure below indicates fewer infections occurred late in the 13 month period of bouffant usage because it took some time for everyone to comply with bouffant use.

Blue is skullcap. Red is bouffant. Time in months

They offer no proof that adoption of the bouffant took several months. In my experience, when hospitals go from skullcaps to bouffants, the transition is abrupt. On the day the mandate takes effect, skullcaps are no longer available. And by the AORN's logic, one could argue that the plot shows a spike in bouffant-associated SSIs at months 4 and 5 of use.

What about statistical significance? The table directly above the figure they cited clearly shows that there was no significant difference in the SSI rate between the two types of headgear for all operations in the hospital, spine cases, or craniotomy/craniectomy procedures.

Click on table to enlarge it.

In fact if you believe in trends, there were slightly more infections for overall operations and spine cases in the bouffant group.

The AORN wants all hair covered. What about the eyebrows? As I mentioned in a post back in May, an outbreak of SSIs that occurred after some plastic surgery operations in Israel was traced to an organism found in the surgeon’s eyebrows.

Bottom line: If the AORN cannot cite evidence proving that scalp or facial hair causes infections, its experts should do their own research and publish it—otherwise stop damaging the organization’s already marginal credibility.

Thanks to Artiger, a loyal reader of my blog posts, for sending me the link to the Becker's article.

Controversies in OR infection control

Like professional athletes, Skeptical Scalpel sometimes talks about himself in the third person. A recent article in Clinical Infectious Diseases [CID] confirms what Skeptical Scalpel has said about a couple of controversial topics in infection control.

The article by surgeons from the University of Washington was published online in late May of this year and gives historical context to some of the standard operating room practices we currently argue about.

Regarding operating room headgear, the authors dissect and refute the positions endorsed by the Association of periOperative Nurses (AORN) that hair and airborne bacteria cause infections. In fact, they say wearing of any kind of hat in the OR may actually disperse more bacteria due to the effect of the hat rubbing against the hair and causing an increase in bacterial shedding.

They conclude “there is little reason to support the AORN recommendations regarding head covering.”

Finally, evidence clarifies the surgical caps controversy

A study of clean surgical cases found no significant difference in wound infection rates for 13 months before and 13 months after the use of bouffant surgical caps became mandatory. Infection rates for the 7513 patients operated on when surgeons were allowed to wear traditional skullcaps, was 0.77%, and for the 8446 patients who had surgery after the bouffant cap mandate, the infection rate was 0.84%. Subgroup analyses of only patients having spine or cranial operations showed similar insignificant differences in wound infection rates.

The study, from a group in Buffalo, New York, was published online in the journal Neurosurgery.

At the 2017 Americas Hernia Society meeting, Dr. Michael Rosen, director of the Cleveland Clinic Comprehensive Hernia Center, presented the results of a survey of 86 surgeon members of the society's quality collaborative.

Ventral hernia repairs were done in 6210 patients with a 4.1% incidence of wound infection. Risk factors for surgical site infection were obesity, hypertension, width of hernia, operation duration greater than two hours, and female sex. The type of cap worn was not associated with the occurrence of a wound infection or any other surgical site complication such as seroma, wound dehiscence, or enterocutaneous fistula.

Of the 79% of surgeons who responded, 48% said they wore disposable skullcaps, 9% wore cloth skullcaps, 29% wore bouffant caps with ears exposed, and 16% wore bouffant caps covering their ears.

[I know that adds up to 102%, but that's what the General Surgery News article about the paper said.]

The report mentioned a series of postoperative infections caused by a mycobacterium at an Israeli hospital in 2004. At the time, a newspaper account of the 15 breast plastic surgery patients said an investigation found the source was a surgeon whose hair and eyebrows were colonized from his home Jacuzzi.

In 2016, the surgeon published a paper about the incident. The organism had never been identified before and was christened M. jacuzzii. Several patients suffered persistent infections and required removal of implants. In the paper, the surgeon revealed he wore a standard paper cap [presumably a skullcap] and the organism was also found on his facial skin.

While some might suggest this paper justifies the use of bouffant caps, the surgeon could still have contaminated the operative field with organisms from his facial skin or eyebrows. Other than with a space helmet, complete coverage of the eyebrows and facial skin is impossible.

The paper from Buffalo had some limitations. It was from a single hospital and was not a randomized trial. However, it was sufficiently powered to detect a difference in infection rates.

The hernia study was not as scientifically rigorous as the Buffalo study, but enough procedures were analyzed to detect a difference in infection rates had one been present.

In the GSN story, the Association of periOperative Registered Nurses (AORN) response to the American College of Surgeons statement supporting the use of skullcaps was quoted. “Wearing a particular head covering based on its symbolism is not evidence-based [nor is the AORN's bouffant cap rule] and should not be a basis for a nationwide practice recommendation.”

Now that we have evidence that skullcaps are not linked to increased infection rates, will the AORN at last get over its obsession with bouffant caps?

My previous posts on this topic can be found here and here.

OR head covering controversy: ACS vs. AORN

In early August, the American College of Surgeons (ACS) issued a statement on operating room attire. Much to my surprise and delight, it said this about headgear:

The skullcap is symbolic of the surgical profession. The skullcap can be worn when close to the totality of hair is covered by it and only a limited amount of hair on the nape of the neck or a modest sideburn remains uncovered. Like OR scrubs, cloth skullcaps should be cleaned and changed daily. Paper skull caps should be disposed of daily and following every dirty or contaminated case.

The Association of periOperative Registered Nurses (AORN) responded with a statement of its own:

Several types of evidence exist that support recommendations that perioperative personnel cover their head and ears in the OR. This evidence includes the fact that human skin and hair is naturally colonized with many bacteria, and perioperative personnel shed microorganisms into the air around them. We know airborne bacteria in the OR can fall into the operative field, contribute to the overall air contamination of the OR, and place patients at risk of surgical site infections. Completely covering the hair can reduce the number of bacteria introduced into OR air by perioperative personnel.

Unfortunately, the "evidence" cited by the AORN is all circumstantial. Yes, human hair and skin may be colonized with bacteria. There is no proof whatsoever that a single surgical patient has ever been infected by a hair or skin droppings from OR personnel. If you want to extend this logic to its inevitable conclusion, the entire neck and face should be covered too. Eyebrows and eyelashes could be deadly. Maybe all OR personnel, including circulating nurses and anesthesia, should wear helmets like those used by astronauts or deep-sea divers.

Some say it is impossible to do a study about this, but one of my Twitter followers came up with a perfectly reasonable suggestion. Simply have several teams of operating room personnel, some of whom are wearing bouffant caps and some wearing skullcaps, stand over an OR table. Instead of a patient, culture media could be placed in strategic locations. The OR teams should move about in scripted ways for an hour or two. Let's see whether there's any difference in the amount of bacteria grown in the cultures.

Perhaps the AORN should get its own house in order first. Many of the OR nurses and techs that I have worked with over the years wear their supposedly fully covering headgear like this: