Course Name: Course Number: Infectious Diseases II PHAR 839 Asal Ardalan Active Learning: Surgical Prophylaxis and Surgical Site Infections During your shift in the hospital, you receive an order for patient MM, a 36 year-old male, for cefoxitin 1 g IV “on call” with the indication for surgical prophylaxis. Upon further investigation of the patient’s chart, you see that they have no drug allergies and 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. What are the likely pathogens for this type of surgery? Enteric gram- negative bacilli (Escherichia coli), anaerobes 2. When would you recommend the nurse to begin the cefoxitin infusion? • 3. Cefoxitin infusion should be started within 60 minutes before the initial incision, as this is the recommended time frame to ensure effective prophylaxis. Under what circumstance would you recommend the nurse to give another dose of cefoxitin? Another dose of cefoxitin should be administered if the surgery lasts more than two half-lives of the drug, which is approximately 2 hours for cefoxitin, or if there is excessive blood loss during surgery. One day post-surgery, MM develops a temperature of 39°C, with a WBC of 14 K/μL. Erythema and induration extending 3 cm from the surgical incision are noted. The patient has no history of MRSA infection or 90-day history of hospitalization with receipt of IV antibiotics. Suture removal along with incision and drainage are performed. 4. What indication(s) does this patient have for antimicrobial therapy? West Coast University PHAR 839: Infectious Diseases II—Fall 2024 Page 1 The patient shows signs of a surgical site infection, such as a temperature of 39°C, elevated WBC (14 K/μL), erythema.These are indications of a significant systemic response that warrants antimicrobial therapy. 5. What antimicrobial regimen would you recommend for this patient’s surgical site infection? For infections following appendectomy with no history of MRSA, a combination of antibiotics effective against gramnegative bacilli and anaerobes is recommended. Cefotetan or cefoxitin would be appropriate for this patient, or an alternative regimen could include cefazolin plus metronidazole. 6. What duration of antimicrobial therapy would you recommend? 24-48 hours West Coast University PHAR 839: Infectious Diseases II—Fall 2024 Page 2