Bariatric Surgery Anesthesia Protocol


Acetaminophen 1000 mg

Gabapentin 600 mg


1. Standard anesthetic management:

a. Avoid nitrous oxide

b. Avoid long acting opioids

c. Check with regional anesthesia for preop TAP Block for intra and postop analgesia

d. Use Bispectral Index for titration of anesthetic agent

e. Use forced air warming on every patient to prevent hypothermia

Induction: Propofol (titrate to effect) , lidocaine (1 mg/kg), esmolol (0.5mg/kg), ketamine (20mg) Rocuronium (0.6 mg/kg)

IV Fluid: 1 L Lactated Ringers bolus at induction

Maintenance: TIVA (using propofol) for >3 on the Apfel PONV risk score

Magnesium 30 mg/kg over 10 min, then 10 mg/kg/h

Ketamine 20 mg/h (infuiosn or divided hourly doses; stop at a total dose of 0.8 mg/kg)

Ibuprofen IV 800 mg at incision

Fentanyl only if objective sign of nociception present

PONV prophylaxis: For all patients: Dexamethasone (4mg IV) at incision, Ondansetron (4mg IV) at skin closure; for >2 risk factors, scopolamine patch (on arrival to hospital), and for >3 risk factor TIVA as maintenance

Intraoperative Ventilation Strategies: Use 6-8ml/kg tidal volumes (prevents volutrauma and lung inflammation); maintain normocapnia (avoid etCO2 < 38 mmHg)

NMB Reversal using appropriate dose of Sugammadex (achieves a full and quick reversal with minimal risk of recurarization while avoids the use of potentially emetogenic neostigmine)


Acetaminophen IV 1000g (when >6 hours after previous dose)

Hydromorphone 0.4 mg IV q15min for pain 3-5

Hydromorphone 0.8 mg IV q15min for pain 6-8

Fentanyl 100 mcg IV q10min for pain 9-10

APFEL Scoring for PONV

(1 point for each)

  • Female gender

  • No smoking status

  • Anticipated use of opioids after Sx

  • h/o PONV or motion sickness

0-2 = Dexamethasone + Ondansetron

3 = + Scopolamine

4 = + propofol infusion or TIVA