Surgical Prophylaxis and Surgical Site Infections

Surgical Prophylaxis and Surgical Site Infections PHAR 839 | Infectious Diseases II Marc Salvatus, PharmD, BCPS West Coast University, School of Pharmacy October 23, 2024 Learning Objectives 1. Identify patient-related risk factors for development of surgical site infections 2. List the most common pathogens associated with infections at various surgical sites 3. Assess appropriateness of timing and duration of prophylactic antibiotics for surgical site infections 4. Recommend an appropriate antimicrobial prophylaxis regimen given the type of surgery 5. Recognize situations where antimicrobial therapy is indicated for surgical site infections 6. Recommend an appropriate antimicrobial regimen for treatment of surgical site infections 2 Resources • Kanji S. Antimicrobial Prophylaxis in Surgery. In: DiPiro JT, Yee GC, Haines ST, Nolin TD, Ellingrod VL, Posey L. eds. DiPiro’s Pharmacotherapy: A Pathophysiologic Approach, 12th Edition. McGraw Hill; 2023. Accessed October 08, 2023. https://accesspharmacy-mhmedicalcom.westcoastuniversity.idm.oclc.org/content.aspx?bookid=3097§ionid=26611024 • Calderwood, M., Anderson, D., Bratzler, D., et al (2023). Strategies to prevent surgical site infections in acute-care hospitals: 2022 Update. Infection Control & Hospital Epidemiology, 44(5), 695-720. doi:10.1017/ice.2023.67 • Ban KA, Minei JP, Laronga C, et al. American College of Surgeons and Surgical Infection Society: Surgical Site Infection Guidelines, 2016 Update. J Am Coll Surg. Jan 2017;224(1):59–74. 10.1016/j.jamcollsurg.2016.10.029. 27915053. • Stevens DL, Bisno AL, Chambers HF, et al. Practice Guidelines for the Diagnosis and Management of Skin and Soft Tissue Infections: 2014 Update by the Infectious Diseases Society of America. Clinical Infectious Diseases. July 2014;59(2):e10-e52. • Bratzler DW, Dellinger EP, Olsen KM, et al. Clinical practice guidelines for antimicrobial prophylaxis in surgery. Am J Health-Syst Pharm. Feb 2013;70:195-283. 3 Epidemiology • 57 million outpatient and 51 million inpatient surgical procedures are performed annually in the U.S.1 • Surgical site infections – most common complication of surgery • Occur in 3% to 6% of patients • Account for 20% of all hospital-acquired infections • Prolong hospitalization by ~7 days → annual cost of $5 billion to $10 billion • Involvement of resistant organism or prosthetic joint → >$90,000 1. National Center for Health Statistics and the National Hospital Discharge Survey 4 Introduction • Prophylactic antibiotics – administered prior to the contamination of previously sterile tissues or fluids with the goal of preventing infection • Prophylactic antibiotics are distinct from antibiotics used for treatment of a pre-existing infection • Differences in spectrum of coverage and timing • Surgical site infections (SSIs) • Occur within 30 days following surgery (within 1 year for prosthetic implantation) • Involve at least one of the following: • Purulent incisional drainage • Positive culture of aseptically obtained fluid or tissue from the superficial wound • Unless culture negative: Local signs and symptoms of pain or tenderness, swelling, and erythema after the incision is opened by the surgeon • Diagnosis by the attending surgeon or physician based on their experience and expert opinion 5 CDC Classifications of SSIs • SSIs can be categorized as incisional (e.g. cellulitis of the incision site) or organ/space (e.g. development of bacterial peritonitis after bowel surgery) 6 Intraoperative Risk Factors National Research Council (NRC) Risk Classification System* Classification Criteria Indication for Antibiotics Clean No acute inflammation or transection of GI, oropharyngeal, genitourinary, biliary, or respiratory tracts; elective case, no technique break Not indicated unless procedure involves implantation of prosthetic materials Prophylactic antibiotics indicated Clean-contaminated Controlled opening of aforementioned tracts with minimal spillage/minor technique break; clean procedures performed emergently or with major technical breaks Acute, nonpurulent inflammation present; major spillage/technique break during clean-contaminated procedure Prophylactic antibiotics indicated Obvious preexisting infection present (abscess, pus, or necrotic tissue present) Therapeutic antibiotics required Contaminated Dirty *Limitations: classification occurs intraoperatively; does not account for patient-specific factors 7 Patient-Specific Risk Factors Risk Factors Comments Age - Nutritional status (preoperative albumin <3.5 g/dL) Malnutrition contributes to impaired wound healing and prolonged hospital stay Diabetes and preoperative glycemic control - Smoking and alcohol use Nicotine impairs wound healing Obesity - Coexisting infections at distal body sites Should be resolved prior to surgery whenever possible Colonization with resistant microorganisms Decolonization of S. aureus using intranasal mupirocin and chlorhexidine Altered immune response E.g. corticosteroid use, HIV, hepatitis C Length of preoperative stay - Bacteriology • Sources of organisms involved in SSIs: • • Endogenous – from the patient’s own flora Exogenous – From contamination during the procedure • Appropriate antibiotics can be selected based on the procedure’s anatomic location and the NRC classification • Most common pathogens in surgical wound infections (NNIS): • • • • • • S. aureus (20% incidence) Coagulase-negative staphylococci (14%) Enterococci (12%) E. coli (8%) Pseudomonas aeruginosa (8%) Candida species and MRSA becoming more prevalent due to broad-spectrum antibiotics 9 10 Scheduling Antibiotic Administration • Considerations for antimicrobial surgical prophylaxis: • Antibiotics should be distributed to the surgical site prior to the initial incision • Bactericidal concentrations of antibiotics should be maintained at the surgical site throughout the surgical procedure • Antibiotic administration should be initiated within 60 minutes prior to the initial incision • Drug distribution throughout the tissues involved in surgery • Exception: vancomycin and fluoroquinolones (120 minutes prior to the initial incision) • Re-dose prophylactic antibiotic when surgery lasts longer than two half-lives of the antibiotic • 4 hours for cefazolin • Duration of prophylactic antibiotics after surgery does not typically exceed 24 hours • Increased risk for C. difficile infection and acute kidney injury 11 Classen DC, Evans RS, Pestotnik SL, et al. "The Timing of Prophylactic Administration of Antibiotics and the Risk of Surgical-Wound Infection." N Engl J Med 1992; 326:281-286. 12 Choice of Antibiotic Dependent on: • Type of surgical procedure • Most frequent pathogens associated with procedure • Safety and efficacy of antibiotic • Literature evidence • Susceptibility patterns of nosocomial pathogens within the institution • Cost 13 Choice of Antibiotic • Parenteral route preferred • Gram-positive coverage • Skin flora: S. aureus, S. epidermidis • Gram-negative and anaerobic coverage if warranted • Based on surgical site • Operation involves transection of a hollow viscous/mucous membrane that may contain resident flora • Cephalosporins most commonly prescribed • Cefazolin preferred • Cefotetan or cefoxitin for broader gram-negative and anaerobic coverage • Vancomycin or clindamycin for Type I penicillin allergy • Vancomycin for prosthetic implantation and high MRSA risk 14 Learning Check 1 During your shift in the hospital, you receive an order for cefoxitin 1 g IV “on call” for surgical prophylaxis. Upon further investigation of the patient’s chart, you see that they are scheduled to undergo an appendectomy at 1300. You look up the pharmacokinetics of cefoxitin and find that the half-life is approximately 1 hour. You then call the operating room nurse to recommend appropriate timing of cefoxitin administration. 1. When would you recommend the nurse to begin the cefoxitin infusion? 2. Under what circumstance would you recommend the nurse to give another dose of cefoxitin 1 g? 15 Recommendations for Specific Types of Surgery Hepatobiliary Surgery Type of Operation / SSI Risk Cholecystectomy NRC: Clean/cleancontaminated SSI risk <5% Likely Pathogens Enteric gramnegative bacilli (E. coli, Klebsiella), enterococci Recommended Prophylaxis Regimen Cefazolin 1 g x1 Alternative for βlactam allergy Comments Clindamycin or vancomycin -plusaztreonam, AG, or FQ High-risk patients only (open biliary tract procedures, acute cholecystitis, common duct stones, previous biliary surgery, jaundice, age >60 years, obesity, diabetes) Not indicated in laparoscopic procedures 16 Laparoscopic Cholecystectomy 17 Recommendations for Specific Types of Surgery Gastrointestinal Surgery Type of Operation / SSI Risk Gastroduodenal NRC: Clean / cleancontaminated SSI risk <5% Likely Pathogens Enteric gramnegative bacilli, grampositive cocci Recommended Prophylaxis Regimen Cefazolin 1 g x1 Alternative for βlactam allergy Clindamycin or vancomycin -plusaztreonam, AG, or FQ Comments High-risk patients only (obstruction, hemorrhage, malignancy, acid suppression therapy, morbid obesity) 18 Recommendations for Specific Types of Surgery Type of Operation / SSI Risk Appendectomy NRC: Contaminated SSI rate 15-30% Likely Pathogens Enteric gramnegative bacilli, anaerobes Recommended Prophylaxis Regimen Cefotetan or cefoxitin 1 g x1 -orCefazolin 1 g x1 -plusMetronidazole 1 g x1 Alternative for βlactam allergy Clindamycin -plusaztreonam, AG, or FQ Comments Re-dose cefoxitin if procedure lasts >2 hours -orMetronidazole -plusAG or FQ 19 Recommendations for Specific Types of Surgery Type of Operation / SSI Risk Colorectal NRC: Contaminated SSI rate 15-30% Likely Pathogens Recommended Prophylaxis Regimen Alternative for β-lactam allergy Comments Enteric gramnegative bacilli, anaerobes Cefotetan or cefoxitin 1 g x1 Clindamycin -plusaztreonam, AG, or FQ Role of mechanical bowel preparation is controversial, but still widely used PO: neomycin 1 g + erythromycin base 1 g + mechanical bowel preparation (e.g. polyethylene glycol or sodium phosphate solutions) -orMetronidazole -plusAG or FQ 20 Recommendations for Specific Types of Surgery Type of Operation / SSI Risk Gastrointestinal Endoscopy Low Likely Pathogens Recommended Prophylaxis Regimen Alternative for β-lactam allergy Enteric gramnegative bacilli, grampositive cocci, oral anaerobes Cefazolin 1 g x1 or ampicillin 2 g x1 Clindamycin or vancomycin -plusaztreonam, AG, or FQ Comments High-risk patients* undergoing highrisk procedures^ *High-risk patients: prosthetic heart valves, history of endocarditis, systemic-pulmonary shunt, synthetic vascular graft <1 year old, complex cyanotic congenital heart disease, obstructed bile duct, liver cirrhosis, immunocompromised ^High-risk procedures: stricture dilation, variceal sclerotherapy, endoscopic retrograde cholangiopancreatography (ERCP) 21 Learning Check 2 Cefazolin monotherapy is an inadequate antimicrobial prophylaxis regimen for the following types of surgery (select all that apply): A. Cholecystectomy B. Gastroduodenal C. Appendectomy D. Colorectal E. Gastrointestinal endoscopy 22 Recommendations for Specific Types of Surgery Urologic Surgery Type of Operation / SSI Risk Likely Pathogens Prostate resection, shockwave lithotripsy, ureteroscopy E. coli Ciprofloxacin 500 mg PO -orBactrim DS 1 tablet PO Unknown (catheters commonly used postoperatively) Removal of external urinary catheters, cystography, urodynamic studies, simple cystourethroscopy Low Recommended Prophylaxis Regimen E. coli Alternative Comments Aminoglycoside with or without clindamycin All patients with positive preoperative urine cultures should receive a course of antibiotic treatment Clindamycin or vancomycin Consider only in patients with risk factors* Cefazolin 1 g x1 *Elderly, anatomic anomalies present, poor nutrition, external catheter, colonized endogenous/exogenous material, coexisting infection, smoker, immunocompromised, prolonged hospital stay 23 Recommendations for Specific Types of Surgery Gynecological Surgery Type of Operation / SSI Risk Likely Pathogens Cesarean section High Hysterectomy High Enteric gramnegative bacilli, anaerobes, group B streptococci, enterococci Antibiotics are given to prevent endometritis Recommended Prophylaxis Regimen Alternative for β-lactam allergy Cefazolin* 2 g x1 and azithromycin 500 mg IV x1 Clindamycin plus AG *2g dose produces adequate concentrations to inhibit anaerobes Vaginal or abdominal: cefazolin 1 g x1 or cefotetan 1 g x1 Clindamycin or vancomycin -plusaztreonam, AG, or FQ -orMetronidazole + AG or FQ Comments Antimicrobial administration should be prior to the initial incision; decreases antibiotic exposure to neonate - Recommendations for Specific Types of Surgery Head and Neck Surgery • Prophylaxis necessary if incision is made through a mucosal layer Type of Operation / SSI Risk Likely Pathogens Maxillofacial surgery NRC: Clean to cleancontaminated Head and neck cancer resection NRC: Clean to cleancontaminated S. aureus, streptococci spp., oral anaerobes Recommended Prophylaxis Regimen Alternative for βlactam allergy Cefazolin 2 g x1 -orclindamycin 600 mg x1 Clindamycin Clindamycin 600 mg at induction and every 8 hours for 2 more doses Comments - - Add gentamicin for clean-contaminated procedures 25 Learning Check 3 Cefazolin monotherapy is an inadequate antimicrobial prophylaxis regimen for the following types of surgery (select all that apply): A. Urologic surgery involving kidney stones B. Cesarean section C. Hysterectomy D. Maxillofacial surgery E. Head and neck cancer resection 26 Recommendations for Specific Types of Surgery Cardiothoracic Surgery • Coronary artery bypass graft (CABG) surgery: 22% mortality rate at 1 year if SSI is developed after surgery (0.6% mortality if no SSI develops) • Risk factors for developing a SSI after cardiac surgery • Obesity • Renal insufficiency • Connective tissue disease • Re-exploration for bleeding • Poorly timed antibiotic administration • Decolonize patients against S. aureus with intranasal mupirocin and chlorhexidine bath for up to 5 days prior to surgery • Cefazolin usually drug of choice for cardiac surgeries • Cefuroxime superior to cefazolin for pulmonary surgeries 27 Recommendations for Specific Types of Surgery Cardiothoracic Surgery Type of Operation / SSI Risk Cardiac surgery NRC: Clean Thoracic surgery NRC: Clean Likely Pathogens S. aureus, S. epidermidis, Corynebacterium S. aureus, S. epidermidis, Corynebacterium, enteric gramnegative bacilli Recommended Prophylaxis Regimen Alternative for β-lactam allergy Cefazolin 1 g Q8H for 48 hours Intranasal mupirocin BID for 5 days preoperatively for patients colonized with S. aureus Cefuroxime 750 mg IV Q8H for 48 hours Clindamycin, vancomycin Comments Patients >80 kg should receive 2 g of cefazolin instead; consider vancomycin in areas with high prevalence of S. aureus resistance First-generation cephalosporins are inadequate 28 Recommendations for Specific Types of Surgery Orthopedic Surgery • Most orthopedic surgery is clean • Prophylactic antibiotics indicated only when prosthetic materials are implanted (e.g. pins, plates, artificial joints) • Infection can result in significant morbidity → prosthesis failure and subsequent removal • Decolonize patients against S. aureus with intranasal mupirocin and chlorhexidine bath for up to 5 days prior to surgery • Drug of choice is cefazolin • Vancomycin for penicillin allergy or high MRSA prevalence • Recommended duration of prophylaxis is 24 hours • Exception: hip fracture repair (48 hours) 29 Recommendations for Specific Types of Surgery Orthopedic Surgery Type of Operation / SSI Risk Likely Pathogens Joint replacement NRC: Clean Hip fracture repair S. aureus, S. epidermidis Recommended Prophylaxis Regimen Cefazolin 1 g x1 preoperatively, then every 8 hours x2 more doses Cefazolin 1 g x1 preoperatively, then every 8 hours for 48 hours NRC: Clean Open/compound fractures Infection presumed S. aureus, S. epidermidis, gram-negative bacilli, polymicrobial Alternative for β-lactam allergy Cefazolin 1 g x1 preoperatively, then every 8 hours for a course of presumed infection Comments Intranasal mupirocin BID for 5 days preoperatively for patients colonized with S. aureus Clindamycin, vancomycin Gram-negative coverage (i.e. gentamicin) often indicated for severe open fractures 30 Recommendations for Specific Types of Surgery Neurosurgery Type of Operation / SSI Risk Likely Pathogens CSF shunt procedures S. aureus, S. epidermidis Cefazolin 1 g x1 Low Craniotomy Alternative for β-lactam allergy Cefazolin 1 g Q8H x3 doses -orceftriaxone 2 g x1 High Spinal surgery Recommended Prophylaxis Regimen Cefazolin 1 g x1 or cefotaxime 1 g x1 Comments No agents have been shown to be better than cefazolin in randomized comparative trials Clindamycin, vancomycin Limited number of clinical trials comparing different treatment regimens Vancomycin 1 g IV x1 for penicillin allergy Low 31 CSF Shunt 32 Learning Check 4 Cefazolin monotherapy is an inadequate antimicrobial prophylaxis regimen for the following type of surgery: A. Cardiac B. Thoracic C. Orthopedic D. Neurosurgery 33 Surgical Site Infections IDSA Practice Guidelines for SSTIs (2014) • All SSIs: suture removal plus incision and drainage • Antibiotics not routinely indicated; may be beneficial in conjunction with I/D and signs of significant systemic response • Short course (24-48 hours) of antibiotics • Especially in operations on the trunk, head and neck, or extremities • MSSA: • MRSA: vancomycin, linezolid, daptomycin, telavancin, ceftaroline • Gram-negatives + anaerobes: cephalosporin or FQ + metronidazole • SSIs following operations on the axilla, GI tract, perineum, or female genital tract 1st-generation cephalosporin, anti-staph penicillin Signs of Significant Systemic Response Erythema and induration extending >5 cm from the wound edge Temperature >38.5°C Heart rate >110 beats/min WBC >12K 34 Summary • Antibiotic administration should be initiated within 60 minutes prior to the initial incision • Exception: 120 minutes for vancomycin and FQs • Re-dose prophylactic antibiotic when surgery lasts longer than two half-lives of the antibiotic • Common pathogens associated with anatomical sites • Spectrum of coverage • • • • Cefazolin Cefotetan/cefoxitin Alternatives in β-lactam allergy Indications for treatment of surgical site infections 35 References 1. 2. 3. 4. 5. 6. 7. 8. 9. Hollingsworth JM, Krein SL, Ye Z, et al. Opening of ambulatory surgery centers and procedure use in elderly patients: Data from Florida. Arch Surg 2011;146:187–193. National Hospital Discharge Survey. Available at: ftp://ftp.cdc.gov/pub/Health_Statistics/NCHS/Datset_Documentation/NHDS/NHDS_2010_Documentation.p df. Berríos-Torres SI, Umscheid CA, Bratzler DW, et al. Centers for Disease Control and Prevention Guideline for the Prevention of Surgical Site Infection, 2017. JAMA Surg. Aug 1 , 2017;152(8):784–791. Hendrick TL, Anastacio MM, Sawyer RG. Prevention of surgical site infection. Expert Rev Anti Infect Ther. 2006;4:223–233. National Academy of Sciences, National Research Council. Postoperative wound infections: The influence ofultraviolet irradiation of the operating room and of various other factors. Ann Surg. 1964;160:32–135. Cruse PJE, Foord R. A five-year prospective study of 23,649 surgical wounds. Arch Surg. 1973;107:206–210. Alexander JW, Solomkin JS, Edwards MJ. Updated recommendations for control of surgical site infections. Ann Surg. 2011;253:1082–1093. NNIS.National Nosocomial Infections Surveillance (NNIS) System Report, data summary from January 1992 through June 2004 issued October 2004. Am J Infect Control. 2004;32:470–485. Classen DC, Evans RS, Pestotnik SL, et al. The timing of prophylactic administration of antibiotics and the risk of surgical wound infection. N Engl J Med. 1992;326:281–286. 36 Thank You • Active learning due at 11:59 PM on Canvas 37