Clinical Scenario:
A 5-year-old child is on mechanical ventilation in the PICU for severe pneumonia. He suddenly develops worsening hypoxaemia, tachycardia and an increase in peak inspiratory pressure from 24 to 38 cmH₂O. Breath sounds are markedly reduced on the right, and chest radiography confirms a right-sided pneumothorax. A chest tube is inserted with improvement in oxygenation.
The child still requires mechanical ventilation. Which ventilator strategy is most appropriate to minimize further ventilator-induced lung injury and air leak?
A. Increase tidal volume
B. Increase PEEP substantially
C. Low tidal volume with individualized PEEP
D. Increase inspiratory pressure
E. Eliminate PEEP completely
Correct answer & Explanation:
Correct answer: C. Low tidal volume with individualized PEEP
Explanation: Mechanical Ventilation in a Child with Pneumothorax
This child has a pneumothorax while receiving positive-pressure ventilation. After the pneumothorax has been decompressed with a chest tube, the ventilator strategy should aim to provide adequate gas exchange while minimizing additional ventilator-induced lung injury and promoting resolution of the air leak.
A low tidal-volume strategy reduces excessive alveolar stretch and is consistent with lung-protective ventilation. Airway pressures should also be monitored closely, particularly when there is an ongoing air leak.
PEEP should not automatically be reduced to zero. PEEP is useful for maintaining alveolar recruitment and oxygenation, but its level should be individualized according to oxygenation, respiratory-system mechanics and hemodynamic tolerance. Pediatric mechanical-ventilation consensus recommendations emphasize this individualized approach.
Why the other options are incorrect
- A. Increase tidal volume: Increases volutrauma and may aggravate the air leak.
- B. Increase PEEP substantially: Excessive PEEP can increase alveolar pressure and may worsen an air leak.
- D. Increase inspiratory pressure: Higher pressures increase the risk of further barotrauma.
- E. Eliminate PEEP completely: PEEP may still be required for alveolar recruitment and oxygenation; it should be individualized rather than routinely eliminated.
Exam Pearl
In a mechanically ventilated child with pneumothorax:
Drain the pneumothorax → use lung-protective ventilation → avoid unnecessarily high pressures/volumes → individualize PEEP.
You can practice another MCQ on Ventilation setting in status asthameticus.
References
- Kneyber MCJ, de Luca D, Calderini E, et al. Recommendations for mechanical ventilation of critically ill children from the Paediatric Mechanical Ventilation Consensus Conference (PEMVECC). Intensive Care Med. 2017;43(12):1764-1780. doi:10.1007/s00134-017-4920-z. [Read the guideline]
- Fernández A, Modesto V, Rimensberger PC, et al.; Second Pediatric Acute Lung Injury Consensus Conference (PALICC-2) of the Pediatric Acute Lung Injury and Sepsis Investigators (PALISI) Network. Invasive ventilatory support in patients with pediatric acute respiratory distress syndrome: from the Second Pediatric Acute Lung Injury Consensus Conference. Pediatr Crit Care Med. 2023;24(12 Suppl 2). doi:10.1097/PCC.0000000000003159. [Read the guideline]
