Diabetes Status and Control

Diabetes mellitus is a well-known risk factor for adverse medical events. Historically, increased risk for infection is thought to result from a combination of the long-term effects of hyperglycemia (e.g., macrovascular and microvascular disease) and the poor wound healing associated with neutrophil, complement, and antibody dysfunction. However, more recent data linking long-term blood glucose control and SSI risk have been mixed. A retrospective Veterans Affairs National Surgical Quality Improvement Program (VA NSQIP) study reported that an elevated Hgb A1c (marker of long-term glucose control) is associated with increased risk of postoperative infections and that Hgb A1c less than 7% was significantly associated with increased infectious complications. However, subsequent studies using multivariable analysis suggest that perioperative hyperglycemia, as opposed to elevated Hgb A1c, is associated with decreased SSI risk. Interestingly, several studies show that perioperative hyperglycemia increases the risk of SSI in both diabetic and nondiabetic patients. These studies suggest that short-term glucose control perioperatively may be more important than long-term Hgb A1c control in preventing SSIs.

Smoking Cessation

Smoking is another well-known risk factor for postoperative infectious complications. The etiology is complex but probably mediated through three principal mechanisms: (1) tissue perfusion and oxygenation, (2) impairment of inflammatory cell functions and oxidative bactericidal mechanisms, and (3) attenuation of proliferative responses including reduced fibroblast migration and collagen synthesis and deposition. The effect of smoking is especially pronounced in cases in which foreign materials or prosthetics are implanted. The negative effect of smoking on SSI risk has been demonstrated across all surgical specialties, with current smokers carrying the highest risk followed by former smokers. The fact that former smokers have a higher risk of SSI compared with those who have never smoked demonstrates that the detrimental effect of smoking is prolonged or possibly even irreversible. Studies have shown that inflammatory cell response and bactericidal mechanisms improve after 4 weeks of abstinence from smoking, but impairment of proliferative responses may persist. Nevertheless, smoking cessation has been shown to be effective in reducing SSI risk and patients should be counseled to refrain from smoking for a minimum of 4 to 6 weeks prior to elective surgery. The effect of nicotine replacement therapy on wound microenvironment and healing is still poorly understood, but there is no evidence to suggest detrimental clinical effects on postoperative outcomes. Current opinion supports the use of nicotine replacement therapy as an aid to smoking cessation before surgery.

Malnutrition

Preoperative malnutrition is a known risk factor for poor outcomes following surgery. Nutritional factors play critical roles in regulating metabolic pathways and immune system functions. A multicenter study found that preoperative hypoalbuminemia was an independent risk factor for SSI development after abdominal surgery. This effect has also been shown in many other types of surgeries. However, there is no consistent evidence for malnutrition screening and nutritional optimization prior to surgery. One Cochrane systematic review evaluated nutritional supplementation in elderly patients recovering from hip fracture that concluded that there is overall low-quality evidence to support nutritional interventions before or soon after surgery to prevent infectious complications.

Preoperative Bathing and Showering

Preoperative antiseptic shower or bath reduces skin bacteria colonization and decreases the risk of contamination at the surgical site. In 1980, Cruse and Foord reported nearly double the SSI rates among patients who did not shower (2.3%) compared with those who showered with chlorhexidine (1.3%). Multiple subsequent studies have found that showering with chlorhexidine-containing products lowered SSI rates. However, a recent Cochrane systematic meta-analysis of randomized controlled trials comparing preoperative bathing with chlorhexidine did not find a statistically significant reduction in SSIs compared with placebo controls. The result may be in part a result of the highly variable surgical patient population and lack of standardized bathing protocols. There is some evidence to suggest that chlorhexidine needs to dry on the skin for maximal effect and repeated applications are superior to a single shower. A recent randomized study showed that a standardized protocol of two or three sequential showers with 4% chlorhexidine gluconate with a 1-minute pause before rinsing resulted in maximal skin surface concentration. Although the evidence for preoperative bathing as an independent practice is inconclusive, it is important to note that preoperative bathing as part of a larger bundle has been shown to be beneficial in reducing SSIs.

MRSA Screening and Decolonization

Nasal carriage of S. aureus has been known as a risk factor for SSI for more than half a century. In 1959, Williams reported an increased risk of wound infection in patients with preoperative nasal carriage of S. aureus and Weinstein found that patients with preoperative colonization of nasal pathogens were more than twice as likely to acquire an infection than those patients with negative nasal cultures. Over the past two decades, many studies have repeatedly demonstrated the association of nasal S. aureus colonization with higher risk of both methicillin-resistant S. aureus (MRSA) and overall SSI among surgical patients. Unfortunately, in the same time frame, the prevalence of MRSA has dramatically increased with current incidence of positive MRSA screen at almost 7%.

The use of MRSA bundles, including screening, decolonization, contact precautions in the hospital, and vancomycin-containing antibiotic prophylaxis, have been shown to decrease SSI rates. Many decolonization protocols have been developed and no single protocol is considered standard and supported by literature. Although a Cochrane systematic review demonstrated that the use of nasal mupirocin alone reduces S. aureus infection, a typical decolonization protocol includes the use of 2% nasal mupirocin twice daily for 5 days and bathing with chlorhexidine gluconate at days 1, 3, and 5 preoperatively. Regardless of the exact components of the protocol, there is evidence to suggest that the decolonization must occur close to the time of surgery to be effective. Routine treatment of all patients and personnel with nasal carriage of MRSA has been carried out in some parts of Europe and Australia and has been proposed in the United States. However, several institutions have found that mupirocin resistance increased with this strategy. At this time, the American Society of Health System Pharmacists recommends screening and nasal mupirocin decolonization for all patients undergoing total joint replacement and cardiac procedures. For all other procedures, hospitals should evaluate their SSI and MRSA rates to determine whether implementation of a screening program is appropriate.

Bowel Preparations

Preoperative bowel preparations for colorectal surgery include the use of mechanical bowel preparation (MBP) alone, oral antibiotics alone, or a combination of both. Although bowel preparations have been shown to be beneficial in reducing SSIs, concern has been raised about potential physiologic derangements related to dehydration that may prolong postoperative recovery. Practice patterns with respect to bowel preparations have evolved over time, but recently they have come full circle to support the use of a combination of MBP and oral antibiotics. A 2011 Cochrane systematic review including 18 randomized studies and 5805 patients did not find statistically significant differences between MBP alone and no MBP in terms of wound infections. Similarly, oral antibiotics or IV antibiotics alone are not effective. However, multiple recent studies show that use of a combination of both mechanical and oral antibiotic bowel preparations results in lower rates of SSI, anastomotic leak, and Clostridium difficile infection.

Asepsis and Surgical Technique

Asepsis is defined as the freedom from infection and the prevention of contact with any microorganism that could cause infection. Aseptic technique refers to the practices that are used by the surgical team to prevent infection during medical procedures. The basic principles of aseptic technique prevent contamination of the open wound, isolate the operative site from the surrounding unsterile physical environment, and create and maintain a sterile field in which the surgery can be performed. Many factors come into play to affect asepsis in the OR including the surgical scrub, appropriate gowning and ungowning, gloving technique, site preparation to reduce the normal flora of the patient, hair removal if necessary, and surgical draping. Excellent surgical technique is critical to reducing the risk for SSI and encompasses preventing hypothermia, maintaining hemostasis, handling tissues correctly, preserving blood supply, avoiding entries into a hollow viscus, removing devitalized tissue, placing drains appropriately, suturing appropriately, eradicating dead space, and managing the postoperative wound.

Hair Removal

Although the origin of the practice of removing hair from the operative site has not been clearly documented, this surgical practice dates back to at least the 1850s at Bellevue Hospital in New York City and has been an established practice since the beginning of the 20th century. Razor shaving is associated with disruption of skin integrity because of microscopic cuts and abrasions that occur on the skin surface, liberating resident dermal bacteria into the operative field, and making the skin environment more favorable to bacterial proliferation. Seropian and Reynolds conducted the first prospective randomized study to challenge this traditional practice and found that SSI rate was nearly 10 times higher when hair was removed by razors (5.6%) compared with depilatory use or no hair removal (0.6%). A landmark 10-year prospective study found that the SSI rate was higher when hair was removed by electric clippers (1.4%) and highest when hair was removed by razors (2.5%) compared with no hair removal (0.9%). As such, hair removal is only recommended when the hair will interfere with surgery and razors are no longer recommended except in the scrotal area or the scalp after traumatic injury. The timing of hair removal is also important. Hair removal immediately prior to the operation is associated with decreased SSI rates when compared with hair removal within 24 hours preoperatively. The Guideline for Prevention of Surgical Site Infection advises that if hair is to be removed, it should be done so immediately before surgery and preferably with electric hair clippers.

Skin Preparation

The primary aim of patient skin antisepsis is to kill or incapacitate microorganisms and to reduce the risk of postoperative infection. Although there is general consensus that skin preparation is necessary prior to incision, the active ingredient in the scrub solution is the subject of debate. Five commercially available antimicrobial ingredients in the United States are approved antiseptic agents for surgical site disinfection: alcohols, chlorhexidine gluconate, iodine/iodophors, parachlorometaxylenol (PCMX), and triclosan. Historically, antiseptic agents progressed from the era of alcohol and carbolic acid to hexachlorophene and PCMX, then to povidone iodine, followed by chlorhexidine gluconate agents. Chlorhexidine gluconate, iodophors (e.g., povidone-iodine), and alcohol-containing products are currently the most commonly used agents, but there have been no well-controlled studies to determine the superiority of any agent. Chlorhexidine gluconate and iodophors have broad spectra of antimicrobial activity. Compared with iodophors, chlorhexidine gluconate has a greater microflora reductive effect, greater residual activity after a single application, and is not activated by blood or serum proteins. However, most randomized trials comparing chlorhexidine-based with iodine-based antiseptics have been underpowered to detect differences in SSI rates. Current evidence suggests that alcohol-based preparations are more effective in reducing SSI than aqueous preparations. Alcohol-based solutions have the most effective and rapid-acting bactericidal effect, but this benefit is limited by its lack of persistent antimicrobial effect. Some newer antiseptic solutions attempt to prolong the bactericidal activity in alcohol-based solutions with the addition of iodine or chlorhexidine. Although there is some evidence that chlorhexidine-isopropyl alcohol is superior to iodine-containing solution plus alcohol in preoperative skin flora decontamination, no study has convincingly demonstrated its superiority with regard to SSIs. Based on current evidence, alcohol-based antiseptics should be used when available. In the absence of alcohol preparations, chlorhexidine might be superior to iodine.

Surgical Hand Scrub

Surgical hand scrubs have been known to play a vital part in preventing surgical site infections for many years, beginning with the pioneering work of Ignaz Philipp Simmelweiss and Joseph Lister in the 1860s. Six commercially available antimicrobial ingredients in the United States are approved antiseptic agents for surgical hand antisepsis: alcohols, chlorhexidine gluconate, iodine/iodophors, PCMX, hexachlorophene, and triclosan. Although the data on the efficacy of microbial killing by these antiseptics demonstrate decreased bacterial colony counts on hands, the impact of the choice of scrub agent on SSI risk has not been evaluated. Several studies have found that alcohol-based antiseptics are more effective than povidone-iodine or chlorhexidine in reducing microbial counts. Historically, they were less frequently used in the United States because of concerns about flammability and drying of skin. ¹⁰¹ However, alcohol-based preparations for surgical hand antisepsis are gaining popularity because they are waterless, involve less scrub time, have a broad spectrum of activity, and do not require brushes. Chlorhexidine gluconate is a popular choice because of the persistence of its effects. It has a strong affinity for skin and remains active for over 6 hours and is not activated by blood or serum proteins. In a study evaluating residual activity following hand disinfection, the greatest sustained activity was achieved by alcoholic chlorhexidine. A recent Cochrane systematic review found that alcohol scrubs reduce colony-forming units (CFUs) compared with aqueous scrubs and that chlorhexidine gluconate scrubs reduce CFUs compared with povidone-iodine scrubs. However, the clinical relevance of this surrogate outcome on SSI risk is unclear and there is an overall low quality of evidence to support any one antiseptic over another.

Factors other than the choice of antiseptic agent influence the effectiveness of the surgical scrub, such as scrubbing technique, duration of scrub, condition of the hands, and techniques used for drying and gloving. Surgical hand antisepsis protocols have traditionally required scrubbing with a brush or sponge, but this practice is damaging to the skin and results in increased shedding of bacteria from the hands. Data now suggest that neither a brush nor a sponge is necessary to reduce bacterial counts on the hands to acceptable levels, especially when alcohol-based products are used. With regards to duration of scrub time, studies suggest that a scrub time of 2 or 3 minutes is as effective as the longer scrub time in reducing hand bacterial colony counts. Recently, waterless surgical scrub formulations have become commercially available. Studies show that waterless chlorhexidine scrub is as effective as traditional water-based scrubs and is acceptable in accordance with each product’s instructions.

Surgical Attire

Appropriate surgical attire helps contain bacterial shedding and promotes environmental control within the OR. Surgical attire typically refers to reusable scrubs consisting of pants and shirt, and sterile gowns. The term can also be extended to the disposable masks, gloves, surgical caps and hoods, and shoe covers that are utilized in the OR. Experimental data show that live microorganisms are shed from hair, exposed skin, and mucous membranes, but there are no well-controlled clinical studies evaluating the effect of surgical attire on SSI risk.

Surgical scrubs consist of pants and a shirt. Policies for laundering, wearing, covering, and changing scrubs vary greatly across institutions. Recently, many formerly acceptable practices, such as laundering scrubs at home and wearing scrubs outside the operating suite, have been called into question. However, there are no well-controlled studies evaluating these practices as an SSI risk factor. Similarly, an acceptable form of surgical caps has been a topic of controversy in recent years. The rationale for surgical caps is to reduce contamination of the surgical field by organisms shed from the hair and scalp. However, no data exists comparing cloth versus disposable hats and skull caps versus bouffant hats. In response to these debates, a task force convened by the American College of Surgeons (ACS) Board of Regents released new guidelines on surgical attire in 2016. These guidelines are based on professionalism, common sense, decorum, and available evidence. They recommend that clean and appropriate professional attire (not scrubs) be worn during all patient encounters outside the OR. OR scrubs should not be worn at any time outside the hospital perimeter. If they are worn outside the OR within the hospital, they should be covered with a clean lab coat or appropriate cover up. Scrubs and hats should be changed at least daily or after dirty or contaminated cases before subsequent cases, even if not visibly soiled. Visibly soiled scrubs from any procedure should be changed as soon as feasible and before speaking with family. Earrings and jewelry worn on the head or neck should be removed or appropriately covered during procedure and the mouth, nose, and hair should be covered during all invasive procedures.

Gowns and Drapes

The use of sterile gowns and drapes is indicated to isolate the sterile field from contamination because they provide a physical barrier between the sterile field and the surrounding sources of microbial contamination such as skin and hair. Regardless of the many materials used for gowns and drapes, the items should be impermeable to liquids and viruses. To meet the standards of the American Society for Testing Materials, the fabrics must be reinforced with films, coatings, or membranes to prevent breakthrough of fluids. Because such materials create increased body heat and may be uncomfortable, surgeons and staff must decide which materials should be selected for their practice.

Antimicrobial Prophylaxis

Antimicrobial prophylaxis refers to a short course of an antibiotic administered prior to the surgery. The goal of antimicrobial prophylaxis is to reduce the number of organisms that could contaminate the operative site to a level that will not overwhelm host defenses. As early as 1961, it was shown that contaminants, including S. aureus , can be recovered from the operative site prior to closure. Burke demonstrated that prevention of SSI required that antibiotics be at an effective concentration in the tissue at the time of contamination. In 1969, Polk and Lopez-Mayor showed decreased rates of wound and intra-abdominal sepsis among patients who received antimicrobial prophylaxis prior to elective gastrointestinal tract surgery. Systemic antibiotics given after the contaminating event had no appreciable effect on the natural history of infection. For antimicrobial prophylaxis to be fully effective, an appropriate antimicrobial agent should be selected based on the type of surgery and the most common SSI pathogens for that surgery. Optimal prophylaxis depends on adequate concentrations being present in the serum, tissue, and wound during the entire time that the incision is open and at risk of contamination. The agent should be active against all potential contaminants and should have the least effect on the normal flora of the body.

There are limited published data on the optimal dosing of antimicrobial prophylaxis. Agents should be administered based on the patient’s weight. In a study of obese patients undergoing gastroplasty, patients who received 1 g of cefazolin had blood and tissue levels of cefazolin consistently below the minimum inhibitory concentration for gram-positive and gram-negative organisms and had higher incidence of SSI compared with patients who received 2 g. Studies also support redosing with antibiotics during surgery to maintain adequate tissue levels based on the agent’s half-life or for every 1500 mL estimated blood loss.

The initial dose of antibiotic should be infused so that its bactericidal concentration is established in serum and tissues by the time the skin is incised and so that it remains at a therapeutic concentration until the incision is closed. Classen found that SSI rates ranged from 0.6% to 3.8% depending on the timing of the infusion. The highest rates were seen when antibiotics were infused more than 2 hours before and again 3 hours after the incision. Rates were lowest at 0.6% among patients who were infused within 2 hours prior to incision. A more recent trial demonstrated similar results where SSI risks were lower with shorter interval between antibiotic infusion and surgical incision. However, other studies indicate that no statistically significant differences in SSI with strict administration windows. In 2003, the Medicare National Surgical Infection Prevention Project (SIPP) committee reviewed all published surgical antimicrobial prophylaxis guidelines and concluded that the infusion of the first antimicrobial dose should begin within 1 hour before incision or within 2 hours for fluoroquinolones or vancomycin. There was no consensus that the infusion must be completed before incision.

Wound Protectors

The concept of using a physical barrier to cover the surgical wound edges has been well-studied over the decades. However, data linking wound protectors with reductions in SSI are mixed. The ROSSINI (Reduction of Surgical Site Infection Using a Novel Intervention) trial was a large, multicenter randomized trial evaluating wound protector use in patients undergoing laparotomy for any emergency or elective procedures and failed to demonstrate significant benefit in SSI reduction. However, many other prospective, randomized trials have demonstrated substantial reductions in SSI rate with the use of plastic wound edge protectors. One meta-analysis pooled data from six RCTs and reported a significant decrease in SSI rates with wound protector use. Although the evidence for wound protector use is mixed, their use is generally supported and their benefit may be more pronounced in more defined patient populations, such as patients undergoing elective colorectal surgery.

Antibiotic Sutures

Inflammation of the surgical site because of the presence of a foreign body, whether it be a prosthesis, a drain, or suture material, can increase the risk of infection. Extensive research compares different types of suture material and infection risk. In general, monofilament sutures are associated with the lowest infection rates. Recently, numerous studies have evaluated the effect of antibiotic sutures on SSI and have found decreased SSI rates with use of triclosan antibiotic sutures compared with standard sutures. These findings are confirmed by systematic review and meta-analysis on the subject.

Wound Closure

As previously described, all wounds can be classified into four major categories: clean, clean/contaminated, contaminated, and dirty/infected. This classification of the degree of contamination in the surgical site has become the traditional system for predicting infection risk and for recommending the type of closure. Classically, primary closure is recommended for clean and clean/contaminated wounds and delayed primary closure or open wound management are recommended for contaminated and dirty wounds. A prospective randomized trial that compared primary closure with delayed primary closure reported lower wound infection rate in the delayed primary closure group. However, a systematic review evaluating eight randomized clinical trials comparing primary closure with delayed primary closure concluded that all studies were at high risk of bias with marked deficiencies in study design and outcome assessment. Although the studies reported reduced SSI risk with delayed primary closure, the effect was no longer significant after accounting for heterogeneity. In the setting of damage-control laparotomy, one study found that primary closure was associated with an increased risk of intra-abdominal SSI compared with open wound management; however, they also found that 85% of primary closure patients did not develop an SSI and were spared the morbidity of managing an open wound.

Perioperative Normothermia

Hypothermia causes numerous adverse outcomes, including morbid myocardial events, coagulopathy with increased blood loss and transfusion requirement, postoperative wound infections, and prolonged hospitalization. The primary connection between thermoregulation and postsurgical resistance to infection is that hypothermia triggers thermoregulatory vasoconstriction, which, in turn, decreases tissue oxygenation. This effect was demonstrated as early as 1996 in a randomized, double-blind, controlled trial, which showed that warming patients for at least 30 minutes preoperatively significantly reduced SSI rates in colorectal surgery. The benefit of perioperative warming has been replicated in multiple randomized controlled trials in both short and long surgical cases. For longer cases, ongoing temperature monitoring and warming measures intra- and postoperatively are indicated.

Perioperative Supplemental Oxygen

There is general support for the use of supplemental oxygen in the perioperative setting in patients with normal pulmonary function. Although some randomized trials have found no benefit or even potentially deleterious effects of supplemental oxygen, most demonstrate that use of supplemental oxygen with 80% FiO ₂ (fraction of inspired oxygen) during and after general anesthesia is beneficial compared with 30% FiO ₂ . These findings were confirmed in a meta-analysis that concluded that supplemental oxygen led to a significant reduction in SSI risk.

Perioperative Glycemic Control

Although many of the long-term effects of diabetes cannot be reversed, evidence suggests that improving glucose control can improve immunologic function and postoperative outcomes. In fact, short-term glycemic control in the perioperative setting is arguably more important than long-term diabetic control in preventing SSIs. There appears to be a dose-response relationship between serum glucose level and SSIs, with patients with serum glucose of less than 130 mg/dL with the lowest SSI rate. Interestingly, although diabetic patients had higher rates of adverse events compared with nondiabetic patients in general, perioperative hyperglycemia posed a greater risk of adverse events in nondiabetic patients compared with diabetic patients. The authors hypothesized that this paradoxical effect may be a result of the underuse of insulin in nondiabetic patients and the higher level of tolerance of hyperglycemia in diabetic patients. Multiple randomized trials also demonstrated that strict glycemic control with glucose targets in the 100 to 150 mg/dL range is superior to liberal glycemic control. However, target rates below 110 mg/dL are associated with adverse outcomes, probably related to hypoglycemic episodes, without incremental benefit in reducing SSI risk. In general, perioperative management of glycemic control to maintain glucose levels between 110 and 150 mg/dL is considered acceptable for SSI prevention.

Ventilation

Microorganisms in the air of the OR can be a potential source of surgical wound contamination. Multiple case studies have traced local epidemics of streptococcal SSIs to airborne transmission from OR personnel. Accordingly, the American Institute of Architects (AIA) has published guidelines for suggested ventilation parameters, including maintenance of temperature between 68°F (20°C) and 73°F (23°C), relative humidity between 30% and 60%, and 20 to 25 total air exchanges per hour (of which three must include fresh air). The CDC additionally recommends that airflow is directed and balanced to maintain positive pressure in the OR rooms with respect to corridors and adjacent areas, that air be introduced at the ceiling and exhausted near the floor, and that all HVAC systems have two filter beds in series.

Laminar airflow with high-efficiency particulate air (HEPA) filters has been shown to be useful primarily in orthopedic and implant surgery, where infection rates have been significantly reduced. Laminar airflow is designed to move particle-free air (ultraclean) over the sterile field at a uniform velocity of 0.3 to 0.5 μm/sec. The ultraclean recirculated air passes through HEPA filters and can be directed vertically or horizontally in the room. A large prospective, randomized multicenter study compared ultraclean air, antimicrobial prophylaxis, and ultraclean air combined with antimicrobial prophylaxis in total hip and knee replacement procedures. Although the results show that SSI rates decreased significantly with combination of antimicrobial prophylaxis and ultraclean air, similar effects were seen with only antimicrobial prophylaxis. A smaller study in spine surgery found a significant difference in SSI rates between ultraclean air and conventional groups even with use of prophylactic antibiotics. However, there is a minimal amount of data to support the use of ultraclean air in other nonorthopedic surgical areas.

Traffic Control

Traffic within the operating suite must be controlled to ensure that only authorized personnel are entering restricted zones, to maintain the separation of clean from dirty areas, and to segregate clean equipment areas from contaminated workrooms. Surgical attire is required for moving around in semirestricted zones such as hallways, offices, or supply rooms that are adjacent to an OR, and a face mask is required when entering a room while a procedure is in progress. Attempts are made to limit the number of personnel in an OR during a procedure. Although there is evidence to suggest that the level of contamination is proportional to the number of personnel in the OR, it is unclear whether there is a link between increased number of personnel and increased SSI risk. Nevertheless, OR traffic should be controlled to decrease the bacterial load of the room by negating both air turbulence and bacterial shedding by personnel in the room.

Cleaning Environmental Surfaces

Environmental surfaces are not routinely implicated in surgical site infections. A randomized study compared cleaning ORs with Wet-Vac routinely between cases and only after contaminated cases and found significant differences in surface contamination but not in postoperative wound infections. However, OR telephones have been identified to be a potential reservoir for SSI-causing bacteria. In general, it is important to maintain a hygienic work environment in the OR. Routine cleaning of environmental surfaces should be performed between cases and at the end of the workday by hospital housekeeping staff trained in the proper techniques of OR cleaning. The decontamination process should begin at the highest level in the room (light tracks, ceiling fixtures) and progress downward to the level of shelves, tables, kickstands, and the floor. The Occupational Safety and Health Administration (OSHA) requires the environmental cleaning of all surfaces that have come in contact with blood or body fluids.

Microbiologic Sampling

According to the CDC Guideline for the Prevention of Surgical Site Infections, there are no standardized parameters for the evaluation and comparison of microbial counts from air sampling or environmental cultures in ORs. Therefore, routine culturing of the OR environment is not recommended. Microbiologic sampling of the environment should take place only if an epidemiologic investigation is being conducted that implicates some areas as a potential source of an outbreak or a cluster of infections.

Sterilization of Surgical Instruments

Nondisposable surgical instruments must undergo physical cleaning followed by sterilization. Sterilization methods included steam under pressure, hydrogen peroxide gas plasma, vaporized hydrogen peroxide, ethylene oxide, or some other ethylene oxide-containing mixture. The most critical issue in instrument reprocessing is the required monitoring of the functional parameters (time, temperature, and pressure) of the sterilization process. Microbiologic and chemical testing of sterilization methods must be performed on a scheduled basis. Protection of the sterility of surgical instruments from time of sterilization until the time of use is critical. Sterilized equipment is generally wrapped in sterile coverings, which are routinely inspected for holes to identify inappropriately sterilized or contaminated contents. However, a study found that holes smaller than 1 cm were often missed by visual inspection, suggesting that more a rigorous technique may be required.

Flash Sterilization

Flash sterilization is the processing of patient care items by steam sterilization when the item is intended for immediate use in a patient procedure. This situation arises when a critical instrument has been inadvertently dropped or another necessary piece of equipment is urgently needed. Flash sterilization is not appropriate for implantable items and it is not to be considered for the convenience or time-saving of the OR schedule. The problems with flash sterilization include a lack of biologic monitoring, an absence of protective packaging, an increased possibility of contamination, and shortened or minimal sterilization cycles. In steam sterilization, the parameters of time, temperature, and pressure are critical for adequately reprocessing a surgical instrument. The use of rapid biologic and chemical indicators has been evaluated and found to be acceptable. It is advisable, however, that flash sterilization be restricted to specific times and events.