Emergency Surgery After Recent Oral Intake: Aspiration Risk Mitigation Protocol

When emergency surgery is needed in a non-fasted patient, a structured protocol minimizes pulmonary aspiration risk.

Risk Stratification and Decision-Making

Urgency assessment: Can surgery wait 4–6 hrs for gastric emptying? (Elective/semi-urgent only).
Gastric volume estimation: Solid meal: 6–8 hrs; clear liquids: 2 hrs. Unknown volume → assume full stomach.

NPO immediately: Nothing by mouth upon surgical decision.
Nasogastric (NG) / Orogastric (OG) tube placement: Decompress stomach; evacuate contents. Confirm placement (aspirate pH, capnography, X-ray).
Pharmacologic prophylaxis (if time permits):
- Metoclopramide 10 mg IV (prokinetic).
- Ondansetron 4 mg IV (antiemetic).
- Ranitidine/famotidine (H2 blocker) or PPI (reduce acidity).
- Sodium citrate 30 mL 0.3M (non-particulate antacid) immediately pre-induction.
Rapid Sequence Induction (RSI):
- Preoxygenation: 3–5 min 100% O₂ (8 vital capacity breaths).
- Cricoid pressure (Sellick's maneuver): Controversial; may impair laryngoscopy; apply only if trained.
- Induction: Propofol/Etomidate/Ketamine + Succinylcholine/Rocuronium.
- No bag-mask ventilation (unless SpO₂ <90%).
- Endotracheal intubation with cuffed tube; confirm (capnography, bilateral breath sounds).
Intraoperative: Maintain slight head-up tilt if feasible; avoid light anesthesia; monitor EtCO₂, SpO₂, airway pressures.
Postoperative: NG/OG tube may remain until bowel function returns; extubate fully awake, protective reflexes intact.

Pregnancy: Increased aspiration risk (progesterone → lower LES tone, uterine compression); RSI mandatory.
Obesity: Higher gastric volume, lower FRC; ramped position, video laryngoscopy.
Bowel obstruction/ileus: NG decompression critical; consider awake fiberoptic intubation.

Team communication (surgery, anesthesia, nursing) and rehearsed protocols are essential for safe non-fasted emergency surgery.