Article Text
Abstract
Background Asthma is one of the most common diseases in children and despite advances in understanding of physiology, pathophysiology, diagnosis and treatment; it still represents a significant health burden. While most deaths occur in the community, the management of the life-threatening exacerbations requiring mechanical ventilation remains extremely challenging.
Aims This review aims to summarise the evidence supporting optimal management of those who have reached the point of needing mechanical ventilation.
Methods A literature review was performed on OVID Medline and Embase with the following criteria:
Asthma* AND
P?ediatric* OR child* AND Ventilat*
All articles were reviewed and further references found from manual review of bibliographies.
Results Early recognition of the need for intubation was associated with improved outcomes. Once ventilated, strategies focus on preventing dynamic hyperinflation and consequences of barotrauma and haemodynamic compromise. In initial stages, controlled modes were preferred with assisted modes facilitating weaning prior to extubation. Permissive hypercapnia with pH >7.2 was found to be well tolerated and enough PEEP to overcome or equal intrinsic PEEP was preferred. Ketamine was deemed the best sedative for its broncho-dilatory effects and neuromusclular blockade, although essential at times, should be limited to the lowest effective dose and discontinued as soon as possible to prevent myopathy.
Conclusions Overall, the mechanical ventilation strategy for children with asthma consists of permissive hypercapnia with pressure limits to prevent barotrauma and low respiratory rate to facilitate a prolonged expiratory phase. Elucidating the finer details of care requires multi-centre randomised controlled trials given the relatively low numbers. While optimising ventilation is important, prevention is more likely to impact on mortality.