The skin is the first and most effective line of defense against infection. When that line is breached - whether it's the purposeful cutting of a patient for surgery, or the unwittingly cracked, dry skin of the surgical staff - microorganisms have a chance to enter the body. Personal protective equipment and surgical drapes shield your clinical team from bloodborne pathogens, but also serve as important barriers against the transfer of potentially harmful microbes to the patient. The use of barrier protection is standard practice, but here are some evidence-based tips and facts that will reinforce the importance of ensuring the safety of your patients.

Hidden dangers
All of us, both patients and clinical staff, carry microorganisms on our skin and in various areas of our bodies. Our normal microbial flora is harmless to us as long as it is in those areas where it normally resides. However, if these microorganisms get into an area of the body that should be sterile, then the microbes have the potential to cause an infection. Surgical incisions break the body's barrier between the microbially populated outside world and sterile sites in the body, thereby putting patients at increased risk for infections.

The most frequent pathogens causing nosocomial infections are the bacteria staphylococci (including MRSA), enterococci (including VRE), Escherichia coli, Pseudomonas aeruginosa, streptococci, Enterobacter species, Klebsiella species, Acinetobacter species and Serratia species; and the yeast Candida albicans. Any of these microorganisms could be part of a person's normal skin, respiratory tract or gastrointestinal tract flora. And many can also be found in the environment with some bacteria, such as the staphylococci and Acinetobacter species surviving for long periods on dry surfaces, while others, such as Pseudomonas prefer a wet habitat.1,2

In a study published in the journal Infection Control and Hospital Epidemiology, researchers examined 1,022 outbreaks of nosocomial infections in a hospital setting.3 These outbreaks ranged from surgical site infections to bloodstream infections. The most common mode of microbial transmission (45.3 percent) was by contact. This study provides a nice overview of the epidemiology of outbreaks, and enumerates a number of means of improving safe contact between clinicians and patients.

Many studies have examined the survival of gram-positive bacteria on hospital surfaces such as countertops, bed rails and glass. Fewer have inspected the lifespan of bacteria on fabrics common to clinical areas. Some of my own research attempted to do just that. I looked at the ability of enterococci and staphylococci to survive on hospital fabrics and plastic - two surfaces that are predominant in today's clinical areas.

The resulting study was published in the Journal of Clinical Microbiology, and examined the survival of 22 gram-positive bacteria on five common materials: smooth 100 percent cotton (clothing), 100 percent cotton terry (towels), a 60-40 polyester blend (scrub suits), 100 percent polyester (privacy drapes) and 100 percent polypropylene plastic (splash aprons).2 We stopped testing after 90 days, and some microorganisms were still present on these materials. Others lasted only a few days, which is certainly long enough for them to be picked up by unsuspecting staff and transferred to patients. We concluded that the long survival of bacteria on commonly used hospital fabrics should be emphasized to staff so that they can understand the importance of following proper contact control protocols, primarily in the area of barrier protection and good hand hygiene.

Clinical tips
A colleague of mine, Charles E. Edmiston Jr., PhD, professor of surgery, pathology and otolaryngology and hospital epidemiologist with the University of Wisconsin in Milwaukee, and a team of researchers studied the airborne transmission of bacteria in the OR and its relation to surgical site infections. They found coagulase-negative staphylococci in the surgical wound area in half of the 70 reconstructive vascular procedures studied, and Staphylococcus aureus in 39 percent of cases.4

Dr. Edmiston and his team identified nasopharyngeal shedding as the source of much of the bacteria, and discovered that surgical masks reduced the amount of shedding by nearly half during the first 90 minutes of surgery. They concluded that the traditional link between patient contact and increased infections needs to be expanded upon, and the potential harm of airborne pathogens must be considered.

The results make sense. We carry organisms as part of our normal nasopharyngeal environment. These organisms get expelled on minute droplets of moisture every time we speak or breathe. During surgery, masks capture these droplets. After a time - about 90 minutes, according to Dr. Edmiston - the surgical mask becomes moistened due to normal humidity levels in the human breath. This moistening gradually reduces the effectiveness of the mask in containing the microorganisms we exhale.

While it's impossible to eliminate the masks' moistening during normal breathing, Dr. Edmiston's research shows the importance of this barrier protection. And to that end, a few common misuses of the mask must be addressed. I've seen a great number of clinicians untie the tops of their masks while leaving the bottom strings tethered, letting the masks flop down on the upper chest as they leave the OR to consult with the perioperative staff or the patient's family. That looks good on TV, especially when done by Dr. McDreamy, but is a practice that fosters the spread of bacteria.

Removing the mask - and all other PPEs, really - in the clinical area where it was used is proper practice. Train staff to untie the mask's bottom before the top. This will eliminate the mask's flopping onto the scrub top or the small area of skin showing through the scrub's V-neck. Remember, in addition to the clinician's microorganisms captured on the mask's inside, the patient's bacteria collect on the outside with every inhaled breath. Letting the mask hang contaminates either the scrub top or the clinician, making them carriers of potentially harmful organisms. So remove masks properly and wash hands before leaving the OR area.

Clinical staff are clearly familiar with the proper way to open and don sterile gloves, taking care to handle them by the cuff. But what about the non-sterile gloves used in pre-op or PACU areas? Most non-sterile gloves are packaged in boxes with an oval opening on top. We've tested the gloves as soon as the boxes are opened and they're amazingly clean.5 However, staff reaching through the oval opening to pull a pair of gloves often touch a part of the glove that will come in contact with the patient. Eliminate this possibility by removing the tops of the boxes. The gloves, lying flat, can then be grabbed using the cuff, as they would if being donned in the sterile OR environment. Why not use the safer practice any time gloves will be touching a patient?

Draping and sterile gowns limit the patient's exposure to potential contamination. Even though surgeons and nurses scrub in and don gloves, limiting their contact to the surgical site, sleeves may inadvertently rub against the patient or bedding, creating another vector for transferring bacteria. Sterile gowns and draping minimize this transfer risk.

Stay vigilant
The hardest type of practices to monitor and change are those that are behavioral. Proper use of protective equipment hinges on changing and reinforcing the behaviors of the clinical staff, as each nurse, surgeon and tech must wear adequate protection every time, all the time. The importance of proper barrier protection in the OR is obvious, but reminders of even the obvious are sometimes needed.

References
1. Neely AN. "A Survey of Gram-Negative Bacterial Survival on Hospital Fabrics and Plastics." J Burn Care Rehabil. 21, 2000: 523-7.
2. Neely AN, and Maley MP. "Survival of Enterococci and Staphylococci on Hospital Fabrics and Plastic." J Clin Microbiol. 38, 2000: 724-726.
3. Gastmeier P, Stamm-Balderjahn S, Hansen S, et al. "How Outbreaks Can Contribute to Prevention of Nonsocomial Infection: Analysis of 1,022 Outbreaks." Infect Control Hosp Epidemiol. Vol. 26, No.4, 2005: 357-361.
4. Edmiston CE Jr, Seabrook GR, Cambria RA, et al. "Molecular epidemiology of microbial contamination in the operating room environment: Is there a risk for infection?" Surgery. 138, 2005: 573-579.
5. Maley MP. "Compliance with Hand Washing." Infect Control Hosp Epidemiol. 21:4, 2000.