Quick Summary

POPES Causes

Initial Actions

MASH Assessment

Diagnostic Algorithm

Advanced Airway Management

Post-Intubation Hypoxia: Identification and Management

Critical Alert

Post-intubation hypoxia can be rapidly fatal without early intervention, which requires a structured approach to concurrently identifying and treating the underlying cause.

Causes of Post-Intubation Hypoxia (POPES)

P: Position of Tube

  • Oesophageal intubation
  • Bronchial intubation
  • Tube out of trachea

O: Obstruction

  • Obstructed tubing
  • Tracheal/bronchial obstruction
  • Bronchoconstriction

P: Patient Factors

  • Pneumothorax
  • Pulmonary embolism (PE)
  • Pulmonary oedema
  • Atelectasis
  • Bronchospasm

E: Equipment Issues

  • Incorrect kit or connections
  • Equipment failure
  • Inadequate gas flow

S: Splinting

  • Abdominal distension
  • Stomach distension
  • Poor paralysis

Structured Approach to Management

Initial Action

Disconnect the ventilator and administer high-flow 100% oxygen (FiO2 1.0) using a bag-valve-mask.

  • Disconnection allows the release of trapped air in a patient with severe bronchospasm (pushing down on the chest can also help to relieve some of the pressure)
  • If patient is easy to hand ventilate and reoxygenate, then the problem probably lies with the ventilator or circuit

Assess Patient (MASH)

M: Movement

Chest wall movement during ventilation - adequate, symmetrical, hyperexpanded

A: Arterial Saturation

Oxygen saturation and PaO2 (obtain ABG)

S: Skin Color

Assess patient's skin color for cyanosis

H: Haemodynamics

Evaluate hemodynamic stability

Diagnostic Algorithm

If the patient is difficult to manually ventilate

Determine if the problem lies with the endotracheal tube (ETT) or with the patient.

If there is little chest movement

A patient problem is still possible, but a problem with the ETT needs to be ruled out urgently:

  • Check ETCO2 and obtain chest x-ray to check position of ETT
  • Pass a suction catheter and/or bougie to ensure ETT is not obstructed
  • Check placement of the tube visually using bronchoscopy or laryngoscopy
  • Consider chest x-ray to check ETT position if hypoxaemia is not critical
  • If in doubt, and hypoxia has not been rapidly resolved, take tube out and replace it

If there is reasonable chest movement

A patient problem is most likely:

  • Perform a focused exam and urgently seek and treat the following life-threatening diagnoses:
  • Pneumothorax (look for asymmetrical chest movement)
  • Lung collapse (look for asymmetrical chest movement)
  • Pulmonary oedema
  • Bronchospasm (chest wall movement may be minimal — look for hyperexpansion)
  • Pulmonary embolism

If the bag is easy to compress during manual ventilation but there is little or no chest movement

Suspect either:

  • A circuit leak (e.g., cuff leak, disconnection or a hole in the circuit)
  • Dislodgement of the endotracheal tube (you may be ventilating the oropharynx or stomach)

If the patient is easy to manually ventilate and the hypoxemia rapidly resolves

The problem is most likely with ventilator/circuit:

  • Check for disconnection of the ventilator/circuit
  • Check ventilator settings
  • Troubleshoot equipment failure

Key Clinical Pearls

Always Verify Tube Position

Use multiple methods: auscultation, ETCO2, and visualization when possible.

Systematic Approach

Follow the structured algorithm to avoid missing critical causes.

Team Communication

Clear communication with the team is essential during airway emergencies.