ASA Physical Status, NPO guidelines, and the 2023 GLP-1 update

ASA I: healthy. ASA II: mild systemic disease, well controlled (controlled HTN, mild asthma, BMI 30-40, current smoker without disease). ASA III: severe systemic disease with functional limitation (BMI ≥40, poorly controlled DM/HTN, COPD, dialysis, MI >3 months ago, EF 30-39%). ASA IV: severe disease that's a constant threat to life (recent MI/CVA/stent <3 mo, severe valve disease, EF <30%, sepsis with end-organ damage). ASA V: moribund — won't survive without surgery (ruptured AAA, massive trauma). ASA VI: brain-dead organ donor. Add 'E' for emergency. ASA is about systemic disease, NOT the surgical risk of the procedure.

Clear liquids: 2 hours (water, black coffee, clear juice — no pulp, no milk). 2023 update: ASA now allows clear liquids up to 2 hours pre-op for minor procedures. Breast milk: 4 hours. Infant formula / non-human milk: 6 hours. Light meal (toast + clear liquid): 6 hours. Heavy/fatty meal: 8+ hours. Emergencies use RSI regardless of timing.

GLP-1 agonists (semaglutide / Ozempic / Wegovy, liraglutide / Saxenda, tirzepatide / Mounjaro / Zepbound) delay gastric emptying significantly. Multiple case reports of retained gastric contents at induction despite standard 8-hour NPO. ASA 2023 guidance: weekly GLP-1 → hold dose ONE WEEK before elective surgery. Daily GLP-1 → hold day of surgery. If unable to hold: gastric ultrasound, or RSI as if full stomach. Ask every patient on a weight-loss or diabetes med: 'is it a once-weekly injection?'

Risk factors that warrant RSI even with adequate NPO: pregnancy >20 weeks, bowel obstruction or ileus, diabetic gastroparesis, esophageal motility disorders, hiatal hernia with reflux, prior bariatric surgery (especially gastric bypass). Modifying meds: H2 blockers (famotidine 20 mg PO) reduce acidity. Metoclopramide 10 mg accelerates gastric emptying. Sodium citrate (Bicitra) neutralizes existing acid — preferred over particulate antacids.