A patient with Mallampati class III, BMI 48 kg/m², and OSA is scheduled for a MRI-guided liver biopsy under MAC sedation at a remote location. What is the MOST important precaution for safe MAC at remote sites?
- A Use of nitrous oxide for analgesia since cylinders are portable
- B Limit procedure to <15 minutes to reduce risk
- C Ensure full anaesthesia monitoring (EtCO₂, SpO₂, NIBP, ECG), immediate access to airway equipment and reversal agents, and anaesthesia machine availability at the remote site ✓
- D Only perform MAC sedation when an anaesthesiologist is NOT required
Explanation
Remote-location anaesthesia (MRI suites, endoscopy, radiology) carries unique hazards: distance from main OR (delayed help), unfamiliar environment, and limited equipment. Standards require ASA standard monitoring including capnography (EtCO₂) — mandatory for all levels of sedation since 2011 ASA guidelines as the earliest indicator of respiratory depression. Obese OSA patients with difficult airway (Mallampati III, high BMI) are at extreme risk for airway obstruction under sedation. An anaesthesia machine and full difficult airway trolley must be immediately available. Nitrous oxide is impractical in MRI (ferromagnetic cylinders are contraindicated).
Reference: Morgan & Mikhail's Clinical Anesthesiology, 6th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.