Which intraoperative temperature monitoring site most closely tracks true core body temperature throughout general anaesthesia, including during rapid fluid shifts and thoracic surgery?
- A Distal third of the oesophagus ✓
- B Axillary skin probe
- C Forehead liquid crystal strip
- D Urinary bladder only when urine output exceeds 100 ml/hour
Correct answer: A. Distal third of the oesophagus
Explanation
B thermistor placed in the distal third of the oesophagus lies adjacent to the heart and great vessels and reliably follows core temperature, including during cardiac surgery and rapid volume changes. Axillary and forehead surface sites lag behind core temperature and are influenced by ambient conditions and peripheral perfusion. Bladder temperature approximates core temperature reasonably well in patients with good urine output but lags when output is low. Pulmonary artery blood temperature is the reference standard where a PAC is already in place.
Reference: Morgan and Mikhail's Clinical Anesthesiology, 5th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.