2006 COURSE TITLE: Preventing Surgical Site Infections

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1 COURSE INTRODUCTION It has been approximately 150 years since Joseph Lister introduced the principles of asepsis and Louis Pasteur conducted research that confirmed the germ theory. One would think that infections resulting from surgery would be rather rare after all of this time. Unfortunately, at least 1.5 million surgical site infections occur annually in the United States. This CE course will describe surgical site infections, identify risk factors for developing surgical site infections, and provide recommendations for minimizing the risk of surgical site infections. Ver /2006 1

2 2006 COURSE TITLE: Preventing Surgical Site Infections Author: Lucia Johnson, MA Ed, CLS(NCA), MT(ASCP)SBB Director of Continuing Education National Center for Competency Testing Number of Clock Hours Credit: 3.0 Course # P.A.C.E. Approved: Yes X No Course Objectives Upon completion of this CE module, the professional will be able to: 1. Discuss the importance of surgical site infections in the United States. 2. Classify surgical site infections using the criteria from the NNIS. 3. Define superficial incisional, deep incisional and organ/space surgical site infections. 4. State the most commonly encountered microorganisms in surgical site infections. 5. List risk factors associated with the development of surgical site infections. 6. Describe recommendations to minimize the risk of surgical site infections. Disclaimer The writers for NCCT continuing education courses attempt to provide factual information based on literature review and current professional practice. However, NCCT does not guarantee that the information contained in the continuing education courses is free from all errors and omissions. 2

3 INTRODUCTION A 2003 report from the Centers for Disease Control and Prevention (CDC) states that approximately 60 million inpatient and outpatient surgical procedures are performed annually in the United States. Surgical site infections (SSIs) occur after 2.6% to 5% of these procedures, resulting in at least 1.5 million SSIs annually. Patients who develop SSIs are 60% more likely to spend time in an ICU, five times more likely to be readmitted to the hospital, and twice as likely to die. SSIs increase the length of hospital stay by seven to ten days and increase the hospital cost by an average of $25,550 per patient. The CDC s National Nosocomial Infections Surveillance (NNIS) system monitors trends in nosocomial (hospital acquired) infections. Based on their reports, SSIs are the third most frequently reported nosocomial infections, accounting for 14% to 16% of all nosocomial infections in hospitalized patients. CLASSIFICATION OF SURGICAL SITE INFECTIONS The NNIS has developed standardized criteria for defining and classifying SSIs. The classifications follow. Incisional SSIs: Up to 80% of reported SSIs are incisional. Their morbidity and mortality are usually controlled once the appropriate treatment is given. Incisional SSIs are further classified as: Superficial incisional SSIs (involves only skin and subcutaneous tissue) and Deep incisional SSIs (involves deeper soft tissues). Organ/Space SSIs: Organ/space SSIs are less frequent but more dangerous. These SSIs involve deeper infection in organs and body spaces. Some studies report that 93% of individuals who develop an organ/space SSI die because of the infection. The following diagram represents the layers exposed during an operation and the potential location of SSIs. Skin Subcutaneous tissue Deep soft tissue (fascia & muscle) Organ/Space Superficial Incisional SSI Deep incisional SSI Organ/space SSI 3

4 Superficial Incisional SSIs To be defined as a SSI, a superficial incisional infection must occur within 30 days after the surgery and involve only the skin or subcutaneous tissue at the site of the incision. In addition, at least one of the following must be present: The incisional site has purulent drainage, with or without laboratory confirmation of an infection. Organisms are isolated from fluid or tissue culture of fluid. Pain or tenderness, localized swelling, redness, or heat is present at the site of incision and the surgeon deliberately opens the superficial incision. NOTE: If the culture results are positive, the site does not need to be opened. The surgeon or attending physician makes a diagnosis of superficial infection. NOTE: Infected burn wounds, episiotomy, newborn circumcision, and stitch abscess are not reported as superficial incisional SSIs. Burns, episiotomy, and circumcision infections have specific reporting criteria. Deep Incisional SSIs To be defined as a deep incisional SSI, the infection must occur within 30 days after the surgery if no implant is left in place or within one year if an implant is in place and the infection appears to be related to the operation. The infection must involve the deep soft tissues (fascia and muscle) of the incision and include at least one of the following: The deep incision has purulent drainage but not from the organ/space component of the site. The incision spontaneously dehisces (breaks open) or is deliberately opened by the surgeon when the patient has at least one of the following: fever of greater than 38º C, localized pain, or tenderness. NOTE: If the culture results are positive, the site does not need to be opened. An abscess or other evidence of infection involving the deep incision is found on direct observation, during re-operation, or by histopathologic/radiologic examination. The surgeon or attending physician makes a diagnosis of deep incisional infection. NOTES Infections that involve both superficial and deep incision sites should be reported as a deep incisional SSI. An organ/space SSI that drains through the incision should be reported as a deep incisional SSI. Organ/Space Incisional SSIs To be defined as an organ/space SSIs, the infection must occur within 30 days after the surgery if no implant is left in place or within one year if implant is in place and the infection appears to be related to the operation. The infection must involve any part of the organ/space site, other than the incision, which was opened or manipulated during an operation. In addition, at least one of the following must be present: Purulent drainage from a drain that is placed through a stab wound into the organ/space. 4

5 NOTE: If the area around a stab wound becomes infected, it is not considered a SSI. It is considered a skin or soft tissue infection, depending on its depth. A culture of the site is positive. An abscess or other evidence of infection involving the organ/space is found on direct observation, during re-operation, or by histopathologic/radiologic examination. The surgeon or attending physician makes a diagnosis of an organ/space SSI. MICROBIOLOGY OF SURGICAL SITE INFECTIONS The pathogens most often isolated from SSIs are Staphylococcus aureus, coagulasenegative staphylococci, Enterococcus spp., and Escherichia coli. An increasing number of SSIs are caused by antibiotic-resistant pathogens, such as methicillin-resistant S. aureus, or by the yeast Candida albicans. The increasing proportions of SSIs caused by the resistant pathogens and Candida spp. are most likely the reflection of the growing numbers of severely ill and immunocompromised surgical patients and the use of broad-spectrum antibiotics. For most SSIs, the source of the pathogen is the patient s skin, mucous membranes, or hollow viscera. The infectious organisms are usually aerobic Gram positive cocci (e.g., staphylococci, streptococci), but can include fecal flora when incisions are made near the perineum or groin. When a gastrointestinal organ is opened in a surgical procedure, Gram negative bacilli (e.g., E. coli), Gram positive organisms (e.g., enterococci), and sometimes anaerobes (e.g., Bacillus fragilis) are the typical causes of SSIs. Outbreaks of SSIs have also been caused by unusual pathogens such as Clostridium perfringens, Legionella spp., and Pseudomonas multivorans. Yeast and fungi have also caused SSIs. Outbreaks such as these have been traced to contaminated dressings, elastic bandages, surgical personnel, tap water, and contaminated disinfectant solutions. RISK FACTORS FOR DEVELOPING SURGICAL SITE INFECTIONS There are widely accepted patient characteristics and surgical issues that may increase the risk of developing SSIs. Patient Characteristics Obesity: When the subcutaneous abdominal fat layer is greater than 3 cm (1.5 inches), the risk of developing a surgical site infection increases considerably. Reasons for the increased risk include the need for a larger incision, technical difficulty of operating through a large fat layer, and decreased circulation to the fat tissue. Infection at another site: Surgery on a patient with an infection at another site may increase the risk of spreading the infection through the bloodstream. Immunocompromised patients: Patients with HIV/AIDS, transplant patients, patients on chemotherapy, and patients using systemic corticosteroids are at a significantly greater risk of developing SSIs, as their immune system is unable to function at an optimal level. 5

6 Other: Age, race, smoking, and presence of chronic diseases such as diabetes are all risk factors for the development of SSIs. Some studies have shown that blood transfusions immediately before, during, and immediately after surgery can also increase the risk of SSIs. The mechanisms by which the risk is increased are not clearly defined for these factors. Surgical Issues Pre-surgical issues Shaving the surgical site to remove hair the day before a surgical procedure is associated with an increased risk of SSI. This is most likely due to the microscopic cuts in skin that allow bacteria easy access to the blood stream. Inadequate/inappropriate use of antiseptics on the surgical incision site or the hands/forearms of surgical team members may allow microorganisms to develop an infection in the patient. Artificial nails or long natural nails worn by surgical team members are associated with increased risk of SSIs. Surgical issues Operating room environment Ventilation: The air in the operating room may contain microbial-laden dust, skin cells, or respiratory droplets. The microbial level in the operating room is directly proportional to the number of people moving about and entering/leaving the room. Environmental surfaces: Although contaminated environmental surfaces (tables, floors, walls, ceilings, lights) in operating rooms are not often the cause of SSIs, the potential for the spread of infection exists. Instrument sterilization: Inadequate sterilization of surgical instruments has resulted in SSI outbreaks. Surgical attire and drapes Attire Surgical attire includes sterile gowns, scrub suits, masks, caps/hoods, shoe covers, and sterile gloves. Microorganisms can be shed from hair, exposed skin, and mucous membranes of surgical personnel. There have been only a few controlled studies to determine the degree of risk of SSI development from surgical attire. However, SSIs have been traced to organisms isolated from the hair and scalp of surgical team members. Surgical attire also protects surgical team members from exposure to blood or body fluids. OSHA regulations require that if a garment(s) is penetrated by blood or other potentially infectious materials, the garment(s) shall be removed immediately or as soon as possible. This requirement would include all types of surgical attire and not just gowns and scrub suits. The exception to this rule would be surgical gloves worn by those individuals performing the actual procedure. However, if a glove becomes punctured or torn, it should be changed as quickly as safety permits. 6

7 Drapes: Drapes are used to create a barrier between the surgical field and potential sources of bacteria. There is limited information on the SSI risk posed by drapes. Drapes should be impervious to blood and body fluids to provide protection of surgical team members from bloodborne pathogens. Asepsis and surgical techniques Asepsis The foundation of surgical site infection prevention is the strict adherence to the principles of asepsis by all scrubbed personnel, including anesthesiologists and nurse anesthetists. Outbreaks of SSIs have been traced to scrubbed personnel who have not followed aseptic techniques. Surgical techniques The practice of excellent surgical technique is widely thought to reduce the risk of SSI. Any foreign body, including suture material, a prosthesis, or drain, may cause inflammation at the surgical site which increases the probability of a SSI. Hypothermia (core body temperature < 36º C) in surgical patients can greatly increase the risk of SSI. Hypothermia increases vasoconstriction, decreases the delivery of oxygen to the wound space, and impairs the function of phagocytic leukocytes. Increased length of surgical procedures is associated with increased risk of SSI. MINIMIZING THE RISK OF SURGICAL SITE INFECTIONS The CDC and several surgery and infection control organizations have made the following recommendations for preventing SSIs. Pre-surgery Whenever possible, identify and treat all infections in the patient before elective surgery. Postpone an elective surgery until the patient s infection has been resolved. Do not remove hair at or around the incision site unless it will interfere with the procedure. If hair must be removed, remove it immediately before the operation with electric clippers. Avoid hyperglycemia (glucose of > 200 mg/dl) in diabetic patients immediately before, during, and immediately after the surgery. Encourage smokers to stop smoking for at least 30 days before an elective surgery. This includes cigarettes, cigars, pipes, and any other form of tobacco use. Do not withhold transfusion of blood products as a means to prevent SSIs. Require patients to shower or bathe with an antiseptic agent the night before or morning of their surgery. Thoroughly wash and clean at and around the incision site to remove gross contamination such as dirt before performing the antiseptic skin preparation. Use the appropriate antiseptic skin preparation. 7

8 Cleanse the incision site with antiseptic solution in concentric circles moving toward the edge of the site. The prepared area must be large enough to extend the incision or create new incisions or drain sites, if necessary. Patients having high-risk surgeries such as prosthetic joint replacement, cardiac pacemaker placement, coronary artery bypass, and most brain surgeries should be given prophylactic antibiotics. The development of SSIs in these patients would be catastrophic. Surgical team members Surgical team members should not wear artificial nails. Natural nails should be kept short. Clean underneath each fingernail prior to performing the first surgical scrub of the day. Perform a pre-operative surgical scrub for at least 2-5 minutes using an appropriate antiseptic. Scrub the hands and forearms up to the elbows. After the surgical scrub, keep hands up and away from the body to assure that water runs from the tips of the fingers toward the elbows. Dry hands with a sterile towel and don a sterile gown and gloves. Do not wear rings, bracelets, watches, etc. on the arms or hands. Train and encourage surgical personnel who have signs and symptoms of a transmissible infectious illness to report conditions promptly to their supervisory and occupational health service personnel. Develop specific policies about patient care responsibilities when surgery personnel have potentially infectious illnesses. The policies should address reporting responsibility, work restrictions, and return to work. Treat the patient with the appropriate antibiotic therapy following published recommendations for specific operations. Do not routinely use vancomycin for surgical antibiotic therapy due to the increase in vancomycin-resistant Enterococci. For elective colon surgery, use enemas and cathartic agents to empty the colon in addition to the appropriate antibiotic therapy. During Surgery Ventilation Maintain positive pressure ventilation in the operating room. Positive pressure prevents air from less clean areas from entering areas with cleaner air. Have at least 15 air changes per hour with at least three being fresh air. Filter all air following the American Institute of Architect s recommendations. Have air enter at ceiling level and exhaust at floor level. Keep operating room doors closed except as needed for passage of equipment, personnel, and the patient. Limit the number of personnel entering the room. Consider performing orthopedic implant surgeries in an operating room supplied with ultraclean (particle free) air. Ultraclean air is moved over the aseptic operating field, sweeping away particles in its path. Ultraclean air is obtained by using a laminar airflow where recirculated air is passed through a high efficiency particulate air filter. Do not use ultraviolet light in the operating room to prevent SSIs. 8

9 Cleaning and disinfection of environmental surfaces When surfaces and/or equipment in the operating room become visibly contaminated with blood or body fluids, use an EPA-approved hospital disinfectant to clean the affected areas before the next surgery in the room. Do not use tacky mats at the entrance of operating rooms as a means of infection control. Use a wet-vacuum and EPA-approved hospital disinfectant to clean the floor after the last operation in that room of the day. Sterilization of surgical instruments Sterilize all surgical instruments according to published guidelines. Use flash sterilization only for items that will be used immediately, e.g., to reprocess a dropped instrument. Surgical attire and drapes Assure surgical masks fully cover the mouth and nose when entering the operating room if an operation is about to begin or is in progress, or if sterile instruments are exposed. Wear a cap or hood to fully cover hair on the head and face when entering the operating room. Scrubbed surgical team members should wear sterile gloves that are put on after donning a sterile gown. Assure surgical gowns and drapes are effective barriers to liquid penetration such as blood and body fluids. Change scrub suits that are visibly contaminated or penetrated by blood or body fluids. Asepsis and surgical technique Use principles of asepsis when placing central venous catheters, spinal or epidural anesthesia catheters, or when dispensing and administering IV drugs. Assemble sterile equipment and solutions immediately before use. Practice good surgical technique. Handle tissue gently to prevent crushing that can result in tissue death. Dead tissue is more likely to become infected. Control bleeding but use electrocautery sparingly because it causes tissue death. Remove all necrotic (dead) tissue, if possible. Avoid spillage of gastrointestinal contents. Minimize dead space. Use monofilament suture material as studies have shown that these have the lowest infection rates. If drainage is needed, use a closed suction drain. Place drains through a separate incision distant from the operative incision. Remove the drain as soon as possible. If the surgeon considers the surgical site to be heavily contaminated, use delayed primary skin closure or leave an incision open to heal. 9

10 Avoid hypothermia as much as possible. Pre- and intraoperative warming, either by forced air warming blankets or heating pads, decreases the SSI rates. These practices maintain a core temperature of 36.5º C and optimize oxygen pressure at the surgical site. Postoperative incision care Protect the primarily closed incision with a sterile dressing for hours postoperatively. Wash hands before and after dressing changes and any contact with the surgical site. Use sterile techniques to change incision dressings. Educate the patient and family about proper incision care, symptoms of SSI, and importance of reporting SSI symptoms. CONCLUSION Surgical site infections are a major source of postoperative illness. A multi-faceted plan involving both patient-specific and surgery-specific issues must be initiated to reduce the unacceptable current rate of surgical site infections. Developing and monitoring the specific recommendations discussed in the article could result in the saving of lives and healthcare dollars in each and every hospital and outpatient surgery setting in the United States. 10

11 REFERENCES Physician s Weekly, LLC. Reducing the Incidence of Surgical Site Infections. Sage Products, Incorporated. Surgical Site Infections: Prevalence, Cost, & Mortality. Clinical Medicine and Research. Preventing Surgical Site Infections. Institute for Healthcare Improvement. Surgical Site Infections. Contemporary OB/GYN. Grand Rounds: Update on Preventing Surgical Site Infections. Infection Control Education Institute. Preventing and Controlling Hospital-Associated Infections: Surgical Site Infections. 11

12 TEST QUESTIONS Preventing Surgical Site Infections Course # Directions: Please answer these questions from the information in the article presented. 1. Patients who develop surgical site infections are as likely to die. a. twice b. three times c. four times d. five times 2. What percent of surgical site infections are classified as incisional? a. 50% b. 60% c. 70% d. 80% 3. Superficial incisional surgical site infections involve the layers exposed during an operation. a. deep soft tissue and organ/space b. organ/space and subcutaneous tissue c. skin and subcutaneous tissue d. subcutaneous tissue and deep soft tissue 4. If an implant is left in place, a surgical site infection can occur up to following the surgery. a. 30 days b. 60 days c. 6 months d. one year 5. The pathogens that most often cause surgical site infections come from the patient s skin, mucous membranes, or hollow viscera. 6. An increasing number of surgical site infections are caused by antibioticresistant pathogens. 12

13 7. Smokers are encouraged to stop smoking at least days before an elective surgery to minimize their chance of developing a surgical site infection. a. 10 b. 20 c. 30 d Staphylococcus aureus is a common cause of surgical site infection in patients undergoing gastrointestinal surgery. 9. Which of the following patient types would be at risk of developing a surgical site infection? a. chemotherapy b. obese c. smoker d. all answers are correct 10. To minimize the risk of surgical site infection, hair should be shaved from the incision site the day before the surgery. 11. Artificial nails worn by scrubbed surgical personnel are associated with an increased risk of surgical site infection. 12. Patients who become hypothermic during an operation are at increased risk for developing surgical site infections. 13. The greater the number of personnel entering and leaving an operating room, the greater the microbial level in the room. 13

14 14. A diabetic patient whose glucose levels during surgery range between 225 mg/dl and 280 mg/dl is at an increased risk for developing a surgical site infection. 15. Operating rooms should have at least 10 air changes per hour with at least three of them being fresh air. **End of Test** 14