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Write a short note on Confirmation of Tracheal Tube Placement.

General Surgery · Final Professional

Importance

Confirming tracheal tube placement immediately after intubation is essential, because an unrecognised oesophageal intubation is rapidly fatal. Confirmation uses a combination of signs, of which capnography is the most reliable.

Methods

The gold standard is capnography — a sustained end-tidal CO₂ waveform over several breaths confirms tracheal placement (an oesophageal tube shows no, or only a brief, trace). Supporting signs: bilateral chest rise and equal breath sounds in both axillae, absence of sounds/gurgling over the epigastrium, misting of the tube, a normal reservoir-bag movement, and maintained oxygen saturation. Direct visualisation of the tube passing through the cords and, if needed, a fibreoptic check also confirm placement.

CLINICAL PEARL

‘No trace = wrong place.’ A sustained capnograph trace is the definitive confirmation; pulse oximetry falls only late (after preoxygenation is exhausted), so it is not an early sign of oesophageal intubation.

DANGER / REMEMBER

Auscultation and chest movement can mislead (e.g. In obesity or with an oesophageal tube), so never rely on clinical signs alone — capnography must be used, and if a trace cannot be obtained and oesophageal placement cannot be excluded, remove the tube.

Continuous Monitoring, Not a Single Check

Confirmation of placement is not a one-off event at intubation but a continuous process: capnography monitors the tube throughout the case, and a sudden loss of the waveform demands immediate evaluation for displacement, disconnection, obstruction or a fall in cardiac output. This is why continuous waveform capnography is now regarded as a minimum standard whenever a tracheal tube or supraglottic airway is used, both in the operating theatre and in the intensive care unit and during transfer.

CLINICAL PEARL

Trust the waveform, not the stethoscope: a sustained end-tidal CO₂ trace is the definitive proof of tracheal placement, oximetry falls only late, and continuous capnography then guards the tube for the rest of the case.

DANGER / REMEMBER

Clinical signs can deceive — chest movement and breath sounds may seem present with an oesophageal tube, especially in the obese — so capnography is mandatory, and a flat trace that cannot be explained means the tube is presumed misplaced and removed rather than left in on the strength of auscultation.

Sustained capnograph trace over several breaths is the gold standard.

KEY POINT

Key points TO remember

Confirm every tube — unrecognised oesophageal intubation is fatal.
Capnography (sustained end-tidal CO₂) is the gold standard: ‘no trace = wrong place’.
Support: bilateral chest rise/breath sounds, no epigastric sounds, tube misting, maintained SpO₂.
Don’t rely on clinical signs alone; SpO₂ falls late; if in doubt, take it out.

EXAM TIP

Sources: Morgan & Mikhail’s Clinical Anesthesiology; Miller’s Anesthesia; Ajay Yadav’s Short Textbook of Anaesthesia.

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