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OR Sterility + Anesthesia Infection Control
TEXTGeneral Principles · 7 min read
Your hands, your stopcocks, your laryngoscope handle. Anesthesia is the #1 vector for OR pathogen transmission — and the #1 lever for SSI reduction.
After this lesson you can
2 min read6 sections- Practice OR sterile technique.
- Apply the SSI bundle.
- Identify blood-borne pathogen exposure response.
- Recall pre-op antibiotic timing.
Hand hygiene — the foundation
15 sec contact minimum.
Soap + water if visibly soiled or post-C. diff (alcohol doesn't kill spores).
Anesthesia compliance rates in observational studies: 2-18%.
Direct correlation between anesthesia hand hygiene and SSI rate.
Use the stopcock-handle-injection-port chain as the highest-risk surfaces.
IV/injection port disinfection
5-15 sec with alcohol pad, dry, then access.Every access, every time.
Propofol contamination — single-vial single-patient use within 6 hr (Diprivan EDTA formulation), discard syringes between patients even if drug remains.
Multi-dose vials only with strict aseptic technique + dating.
Never re-enter a syringe to a vial.
Surgical site infection (SSI) prevention bundle
Re-dose at 2× drug half-life (typically cefazolin q4h) or after 1500 mL EBL.
Weight-based: cefazolin 2 g <120 kg, 3 g ≥120 kg.
Normothermia (≥36°C) — every 1°C below cuts neutrophil function.
Glycemic control (target 110-180 mg/dL intra-op, avoid <110 → hypoglycemia).
Supplemental O2 (controversial — WHO's 2016 recommendation of 80% FiO2 intra/post-op was qualified/walked back in subsequent 2018-2020 updates citing weak evidence + oxygen-toxicity concerns; current guidance is more nuanced and titration-based).
Anesthesia equipment between cases
Handles previously thought 'low risk' — now classified semi-critical, require disinfection.
Reusable ETT/LMAs — high-level disinfection (e.g., Cidex OPA).
Anesthesia workstation surfaces — quaternary ammonium wipe between cases.
Circle system — internal contamination rare with HME viral filter at Y-piece (change between patients; circuit can stay 1-7 days per institution).
Standard + transmission-based precautions
Contact (MRSA, VRE, C. diff): gown + gloves.
Droplet (influenza, meningitis): surgical mask within 6 ft.
Airborne (TB, varicella, measles, COVID aerosol): N95 + negative-pressure room.
Intubation generates aerosols — N95 + face shield for any suspected airborne.
Don/doff sequence drills reduce self-contamination.
Bloodborne pathogen exposure response
- wash with soap + water immediately
- document
- report to employee health within hours
Source-patient testing for HIV/HBV/HCV.
HIV PEP within 2 hr ideally, ≤72 hr window — 28-day tenofovir/emtricitabine + dolutegravir.
HBV: confirm immunity (anti-HBs ≥10), HBIG + booster if non-immune.
- never recap
- blunt-fill needles for drug draw
- safety syringes
⚠ Common pitfalls
- Pre-op antibiotic >60 min before incision — efficacy drops; redose intraop if case > drug half-life × 2.
- Skipping hub disinfection on IV ports — bloodstream infection source.
- Reaching across the sterile field — break in sterile technique.
- Treating needlestick exposure with delay — HIV prophylaxis effective ≤72 hr.
💎 Clinical pearls
- Standard pre-op antibiotic: cefazolin 2 g (3 g if >120 kg) within 60 min of incision.
- Redose at half-life × 2 (cefazolin q-4h, vancomycin q-12h) or if EBL >1500 mL.
- Glucose control intra-op: <180 mg/dL reduces SSI in colorectal + cardiac surgery.
- Maintain normothermia (>36 °C) — SSI risk doubles when hypothermic per Kurz 1996.
Recap
- Standard pre-op antibiotic: cefazolin 2 g (3 g if >120 kg) within 60 min of incision.
- Redose at half-life × 2 (cefazolin q-4h, vancomycin q-12h) or if EBL >1500 mL.
- Glucose control intra-op: <180 mg/dL reduces SSI in colorectal + cardiac surgery.
- Maintain normothermia (>36 °C) — SSI risk doubles when hypothermic per Kurz 1996.
Mark each section done to complete the module.