Roux-en-Y Gastric Bypass (RYGB)

• Drug dose adjustment for Bariatric Patients SOBA Calculator
• Obesity Surgery Mortality Risk Score MDCalc
• STOP-Bang MDCalc
• Involves MDT management with optimisation of comorbidities

Pre-Induction

• Consider high-flow nasal cannulae during pre-oxygenation
• Pre-oxygenation in ramped position
• BIS monitoring

Drugs (TCI)

• remifentanilTCI
• propofolTCI
• rocuronium0.6mg/kg

Intubation

• Videolaryngoscopy
• AirwayETT

Post-Induction

• ProcedureOrogastric Tube Insertion36Fr
• Position OG tube within oesophagus

Maintenance

• propofolTCI
• remifentanilTCI

Analgesia

• morphine0.1mg/kg or fentanyl2-3mcg/kg
• magnesium sulphate2.5g
• paracetamol1g
• diclofenac75mg or

Gastric decompression

• Reduces gastric volume, improves laparoscopic exposure, lowers aspiration risk

Gastric pouch sizing

• At surgeon's request, withdraw OG tube to just below the gastro-oesophageal junction
• Advance slowly under direct communication with surgeon to guide pouch creation
• Do not advance beyond GOJ until stomach has been divided — risk of inadvertent passage into excluded stomach

Leak testing (anastomosis)

• Abdominal cavity filled with saline solution
• At surgeon's request, oxygen insufflated at 2l/min into gastric pouch, then released
• Surgeon watches laparoscopically for bubbles

Recovery Use

• fentanylIV, 10-20mcg, PRN
• morphineIV, 1-2mg, PRN

Analgesia

• tramadolPO/IV, 50-100mg, QDS PRN
• morphinePO, 5-10mg, QDS PRN
• morphineSC, 5-10mg, QDS PRN
• Paracetamol1g QDS

Anti-emetics

• ondansetron4mg, TDS