Minimizing Fasting Times

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ERAS & Fasting Basics - Hunger Games Shift

  • ERAS: Evidence-based, multimodal care to reduce surgical stress & hasten recovery.
  • Traditional NPO: Prolonged fasting → dehydration, insulin resistance, patient distress.
  • ERAS Goal: Minimize fasting for:
    • Better hydration, ↓PONV.
    • Improved insulin sensitivity.
    • Enhanced patient comfort.
  • Key Pre-op Times:
    • Clear fluids: up to 2 hrs.
    • Light meal: 6 hrs.

⭐ ERAS protocols allow clear carbohydrate drinks up to 2 hours before surgery, reducing postoperative insulin resistance and improving patient comfort without increasing aspiration risk in most patients.

Current Fasting Rules - Sip, Sip, Hooray!

  • ASA/ISA Consensus (Adults & Children):
    • Clear Fluids: 2 hours (water, no-pulp juice, black tea/coffee)
    • Breast Milk: 4 hours
    • Infant Formula / Non-human Milk: 6 hours
    • Light Meal (e.g., toast): 6 hours
    • Heavy/Fried Meal: 8 hours
  • 📌 "2-4-6-8 Rule": Clear fluids → Breast milk → Formula/Light meal → Heavy meal.
  • Oral medications: Typically with sips of water up to 1 hour pre-op.
  • NPO Guidelines: Fasting Times for Various Intake Types

⭐ Preoperative oral carbohydrate drinks (e.g., maltodextrin) 2 hours before surgery can ↓PONV & ↓insulin resistance, improving patient comfort and recovery under ERAS protocols.

Physiology of Shorter Fasts - Gut Feelings & Gains

  • Shorter Fasts: Physiological Wins
    • Maintains hydration & crucial liver glycogen stores.
    • Reduces surgical stress response, ↓ catabolism.
    • ↓ Insulin resistance: Pre-op carbs (e.g., maltodextrin 2-3 hours prior) prevent starvation-induced resistance.
    • Better glycemic control: Avoids fasting hypoglycemia & stress hyperglycemia.
    • ↑ Patient comfort: Significantly less hunger, thirst, anxiety.
    • ↓ PONV: Linked to better hydration & reduced ketosis.
    • Earlier gut function return: Gentle gut stimulation.
  • Prolonged Fasts: Physiological Toll
    • Induces insulin resistance, mimics a starved state.
    • ↑ Protein breakdown, dehydration, electrolyte disturbances.

⭐ Allowing clear fluids up to 2 hours before surgery significantly reduces patient-reported thirst and anxiety, improving overall experience. ERAS Protocols: Fasting, Recovery, and Patient Comfort

Fasting in Special Groups - Tricky Tummies & Alerts

Modify ERAS fasting for special groups. Balance aspiration risk vs. minimal fasting benefits.

  • Diabetes Mellitus:
    • Risks: Hypo/hyperglycemia.
    • Mgmt: Monitor glucose. Adjust meds. Morning list preferred.
  • GERD/Gastroparesis/Hiatus Hernia/Bowel Obstruction:
    • ↑ Aspiration risk.
    • Mgmt: PPI, H2 blockers, prokinetics. RSI. Solids >6-8h, clears >2-4h (case-by-case).
  • Obesity (BMI >35 kg/m²):
    • ↑ Gastric volume & pressure.
    • Mgmt: ERAS often safe. Individualize. Consider RSI.
  • Obstetrics:
    • Elective C-Section (non-laboring): ERAS (solids 6h, clears 2h).
    • Laboring/Emergency: Assume full stomach. NPO. RSI.
    • ⭐ > Parturients in active labor are always considered to have a full stomach.
  • Emergency Surgery:
    • Assume full stomach. NPO. RSI mandatory.

Pre-Op Carb Drinks - Sweet Surge Strategy

  • Goal: Transition from fasted to fed metabolic state before surgery.
  • Key effect: ↓ postoperative insulin resistance.
  • Protocol: 50g CHO (e.g., maltodextrin) in clear liquid.
    • Given 2 hours before anesthesia induction.
  • Benefits: ↓ thirst, hunger, anxiety; ↓ PONV; preserves muscle.
  • Improves patient comfort & glycemic control.

⭐ Preoperative CHO loading can reduce postoperative insulin resistance by up to 50%.

  • Caution: Gastroparesis, severe reflux, emergency surgery.

High‑Yield Points - ⚡ Biggest Takeaways

  • Clear fluids (water, pulp-free juice) allowed up to 2 hours before surgery.
  • Solids (light meal) permitted up to 6 hours before surgery.
  • Preoperative carbohydrate drinks (e.g., maltodextrin) 2 hours preoperatively reduce insulin resistance.
  • Prolonged fasting offers no benefit; increases PONV and insulin resistance.
  • Infants: breast milk 4 hours, formula 6 hours fasting.
  • Goal: Enhance patient comfort, reduce catabolic state, improve glycemic control.

Practice Questions: Minimizing Fasting Times

Test your understanding with these related questions

What is the most appropriate insulin regimen for achieving tight control of blood sugar levels in a 20-year-old male with type 1 diabetes mellitus?

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Flashcards: Minimizing Fasting Times

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_____ is an IV anesthetic that can be used to reduce postoperative pain

TAP TO REVEAL ANSWER

_____ is an IV anesthetic that can be used to reduce postoperative pain

Ketamine

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