Shout out to Taylor DeGiulio for today’s episode idea! We’re doing a pretty close reading of ACOG PB 195 if you want to follow along!
SSI represents the most common complication after GYN surgery, however definitions of this may surprise you. The National Surgical Quality Improvement Program (NSQIP) divides SSI up into three broad categories, with their definitions below:
Superficial incisional: occurs within 30 days of surgery, involving only skin or subcutaneous tissue.
Deep incisional: occurs within 30 days of surgery without an implant, or within 1 year of surgery with an implant, and involves deep soft tissues (rectus muscle, fascia).
Organ space: occurs within 30 days of surgery without an implant, or within 1 year of surgery with an implant, and involves any other area manipulated during operative procedure (i.e., osteomyelitis if bone, endometritis or vaginal cuff for GYN, etc.)
In addition to satisfying these time and location definitions, an SSI also must have one of the following characteristics present:
Purulent drainage from the area of infection.
Spontaneous dehiscence or deliberate opening of a wound by the surgeon, with organisms subsequently obtained from an aseptically collected culture; or not cultured, but the patient displays signs/symptoms) of infection (i.e., fever, localized pain or tenderness, redness, etc.).
Abscess or other evidence of infection noted on examination.
Diagnosis of infection made by surgeon or attending physician.
In GYN surgery, our threats for infection lie primarily from vaginal organisms or skin organisms; however we may also come into contact with fecal content or enteric contents as well. Thinking about the organisms we’re helping to bolster defense against will help in selecting a preventive antibiotic. Thinking about the wound class is a simple way to characterize this:
ACOG also recommends a number of perioperative considerations/techniques to reduce SSI:
Treat remote infections - this one seems pretty obvious. If there’s an infection going on, like a skin infection or a UTI, it’s likely best to postpone surgery in favor of treating the infection!
Do not shave the incision site - Preoperative shaving by patients themselves has actually been shown to be likely harmful, increasing the risk of infection by introducing a nidus for infection remote from surgery. If hair needs to be clipped, it should be done immediately pre-op with electric clippers.
Prevent preop hyperglycemia - blood glucose should be targeted to < 200 mg/dL for both non-diabetic and diabetic patients before proceeding with surgery. Performing a preoperative random blood sugar prior to major surgery is a practice our hospital has implemented to identify diabetes in our patients, and to prevent SSI.
Advise patients to shower or bathe with full body soap on at least the night before surgery -We found it fairly surprising that no particular soap is recommended over another. Many offices offer patients a chlorhexidine soap for use the night before surgery. The soap significantly reduces risk of cellulitis versus no bathing.
Use alcohol-based preop skin prep, unless contraindicated - chlorhexidine-alcohol combinations have been proven in RCTs and meta-analyses to be superior to povidine-iodine for preoperative skin preparation. For mucosal sites such as the vagina, where high alcohol concentrations should not be used due to irritation risk, povidine-iodine or chlorexidine soap solutions should be used.
Maintain appropriate aseptic technique - Of course, right? But in addition, our surgical technique does matter! Effective hemostasis while preserving vital blood supply, maintaining normothermia and reducing operative time, gentle tissue handling, avoiding inadvertent injuries, using drains when appropriate, and eradicating dead space can all help to reduce risk of SSI.
Minimize OR traffic - safety bundles that have included components to reduce opening of OR doors during cases have been shown to reduce SSI.
For hysterectomy, consider preop screening for bacterial vaginosis - prior to routine use of antibiotic prophylaxis for hysterectomy, use of metronidazole pre-op in patients who screened positive for BV reduced SSI. These studies haven’t been repeated with systematic antibiotic prophylaxis, but given the data, ACOG does state that screening is reasonable at the preop visit.
Alright, now time for the antibiotics! We dive deeper in the podcast, but PB 195 will give you the quick version here in the tables: