Respiratory arrest & peri-intubation
Before and after positive pressure: find the RV, tamponade and volume problems that turn intubation into arrest.
Echo approach, step by step
Respiratory arrest (apnoea with a pulse) needs an airway and ventilation immediately [198]. The echo questions are: why did breathing fail, and will the circulation tolerate positive pressure?
- Before induction, if time allowsRV size and function (PE, PH), tamponade, LV function, volume status [3,124,149].
- Cause of respiratory failurePulmonary oedema (B-lines, low EF), PE (dilated RV), pneumonia (consolidation) [199].
- After intubationBilateral lung sliding (tube not in a bronchus; no pneumothorax) [202].
- After starting ventilationWatch the RV: acute RV dilatation, fall in VTI and septal shift show RV intolerance to PEEP [152].
- RV size and function
- Effusion
- LVEF
- Volume
- Bilateral sliding after intubation
- VTI before and after ventilation
Causes & echo clues
| Cause of respiratory failure | Echo / lung clue |
|---|---|
| Opioid or sedative overdose, neurological | Normal heart; hypoventilation |
| Pulmonary oedema | Bilateral B-lines, low EF or high E/e′ [199] |
| PE | Dilated RV [124] |
| Severe asthma or COPD | Hyperinflation; A-profile [199] |
| Neuromuscular exhaustion | Normal heart |
| Tension pneumothorax | No sliding [199] |
Clinical pathway to the diagnosis
- VentilateBag-mask, supraglottic device or intubation per ALS [198].
- Check the pulse; if absent, start CPR [198].
- Blood gas, glucose, toxicology, naloxone if opioids suspected.
- Echo and lung ultrasound[199,202].
Clinical pearls & pitfalls
Practical tipSevere RV failure (massive PE, PAH): pre-oxygenate, give a vasopressor before induction, use low PEEP and small tidal volumes, and avoid hypercapnia [124].
- A plethoric IVC in a ventilated patient means little. Use RV size and VTI instead [3].
Red flags
- Shock index >1 or hypotension before induction
- Dilated, failing RV (PE, PH) → high risk of collapse with positive pressure [124]
- Effusion with collapse → drain before intubation if possible [149]