Full Stomach Considerations

Full Stomach: Risks & Recognition - Tummy Trouble Timebomb

• Definition: Presence of gastric contents posing aspiration risk.
  • Solids <6-8h, clear fluids <2h prior to anesthesia.
  • Delayed emptying: trauma, pain, opioids, pregnancy, diabetes, GERD.
• Primary Risk: Pulmonary aspiration.
  • Leads to: pneumonitis (chemical), pneumonia (bacterial).
  • ↑ Morbidity & mortality.
• Recognition:
  • History: Last oral intake (LOI).
  • Clinical: Nausea, vomiting, distension.
  • Gastric ultrasound (POCUS).
• Emergency Context: Always assume full stomach in emergencies.

  ⭐ Gastric POCUS (Perlas Grade 0, 1, 2) helps assess aspiration risk.

Pre-Anesthetic Assessment & Prep - Stomach Safeguards

• Assessment:
  • History: Last meal (nature, timing), GERD symptoms, gastroparesis.
  • Conditions delaying gastric emptying: Diabetes, trauma, pain, opioids, pregnancy, obesity, ↑ICP, bowel obstruction.
• Pharmacological Safeguards (Administer ASAP):
  • Reduce acidity:
    • Non-particulate antacid: Sodium Citrate $0.3M$ 15-30ml orally (immediate action).
    • H2-receptor antagonist: Ranitidine 50mg IV (onset 30-60 min), Famotidine 20mg IV.
    • Proton Pump Inhibitor (PPI): Pantoprazole 40mg IV (onset ~60 min).
  • Promote emptying (if no obstruction):
    • Prokinetic: Metoclopramide 10mg IV (onset 15-30 min). ⚠️ Caution: bowel obstruction, Parkinson's.
• Non-Pharmacological:
  • Consider NGT/OGT for gastric decompression (balance risk/benefit).

⭐ Sodium citrate is preferred for immediate gastric fluid pH elevation as it's non-particulate and acts on contact, unlike H2 blockers or PPIs which require absorption and time for systemic effect on acid production.

Rapid Sequence Intubation (RSI) - Airway Express Lane

Gold standard for airway in full stomach; minimizes aspiration risk. Near-simultaneous sedative & neuromuscular blocker. No Positive Pressure Ventilation (PPV) before intubation.

Key Principles & Steps:

• Preparation (SOAP ME 📌): Suction, O₂, Airway, Pharmacy, Monitors, Emergency equip.
• Preoxygenation: 3-5 min 100% O₂ or 8 Vital Capacity breaths.
• Pre-treatment (Optional 📌): Consider Lidocaine (1.5 mg/kg), Fentanyl (1-2 mcg/kg), Atropine (peds with Sux). Defasciculating dose for Sux.
• Paralysis with Induction:
  • Induction: Propofol 1.5-2.5, Etomidate 0.2-0.3, Ketamine 1-2 mg/kg.
  • Paralytic: Suxamethonium 1-1.5, Rocuronium 0.9-1.2 mg/kg.
• Protection & Positioning: Cricoid pressure (~30N post-LOC). Sniffing position.
• Placement & Proof: Intubate, confirm (EtCO₂, auscultation).
• Post-intubation: Secure ETT, ventilate.

⭐ Etomidate (0.2-0.3 mg/kg) is favored for induction in RSI for trauma or hemodynamically unstable patients due to its cardiovascular stability.

Extubation & Post-Op Care - Safe Wake-Up Call

• Extubation (Full Stomach):
  • Fully awake, alert, commands obeyed.
  • Intact airway reflexes (cough, gag).
  • Adequate respiration: TV > 5 ml/kg, RR 12-25/min, NIF < -20 cm H₂O.
  • SpO₂ > 95% (FiO₂ ≤ 0.4). TOF ratio > 0.9.
• Post-Op:
  • Semi-Fowler's/lateral position.
  • Monitor for aspiration. Antiemetics.

⭐ Awake extubation is standard for full stomach patients to reduce aspiration risk.

Aspiration: Management Protocol - Damage Control Mode

• Key Goals: Prevent further soilage, maintain oxygenation.
• Immediate Steps:
  • Position: Head down, lateral.
  • Suction: Oropharynx & trachea.
  • Airway: Intubate, 100% O2, PEEP.
• Consider: Bronchoscopy for solids.
• Avoid: Routine prophylactic antibiotics/steroids.

⭐ Aspiration pneumonitis is a chemical lung injury; antibiotics for later infection signs.

High‑Yield Points - ⚡ Biggest Takeaways

• Aspiration pneumonitis is the primary concern with a full stomach in emergency surgery.
• Rapid Sequence Intubation (RSI) is the cornerstone of airway management to minimize aspiration risk.
• Cricoid pressure (Sellick's maneuver), though controversial, is often applied until ETT cuff inflation.
• Thorough pre-oxygenation (denitrogenation) is vital to extend safe apnea time during intubation.
• Avoid or minimize positive pressure ventilation (PPV) via mask before securing the airway.
• Consider awake fiberoptic intubation (AFOI) for anticipated difficult airway with a full stomach.
• Ensure patient is fully awake with intact protective airway reflexes before extubation post-surgery.