Acute asphyxial
asthma (AAA) is well described in adult patients and is characterized by a sudden onset that may rapidly progress to a near-arrest state. Despite the initial severity of AAA,
mechanical ventilation often restores gas exchange promptly, resulting in shorter durations of ventilation. We believe that AAA can occur in children and can lead to
respiratory failure that requires
mechanical ventilation. Furthermore, children with rapid-onset
respiratory failure that requires intubation in the emergency department (ED) are more likely to have AAA and a shorter duration of
mechanical ventilation than those intubated in the pediatric intensive care unit (PICU).
METHODS: During the study period, 33 (11.4%) of 290 PICU admissions for
status asthmaticus required
mechanical ventilation. Thirteen children presented with rapid
respiratory failure en route, on arrival, or within 30 minutes of arrival to the ED versus 20 children who progressed to
respiratory failure later in their ED course or in the PICU. Mean duration of
mechanical ventilation was significantly shorter in the children who presented with rapid
respiratory failure versus those with progressive
respiratory failure (29 +/- 43 hours vs 88 +/- 72 hours). Children with rapid
respiratory failure had greater improvements in ventilation and oxygenation than those with progressive
respiratory failure as measured by pre- and postintubation changes in arterial
carbon dioxide pressure, arterial
oxygen pressure/fraction of inspired
oxygen ratio, and alveolar-arterial gradient. According to site of intubation, 23 children required intubation in the ED, whereas 10 were intubated later in the PICU. Mean duration of
mechanical ventilation was significantly shorter in the ED group versus the PICU group (42 +/- 63 hours vs 118 +/- 46 hours). There were significantly greater improvements in ventilation and oxygenation in the ED group versus the PICU group as measured by pre- and postintubation changes in arterial
carbon dioxide pressure and arterial
oxygen pressure/fraction of inspired
oxygen ratio.
CONCLUSIONS: AAA occurs in children and shares characteristics seen in adult counterparts. Need for early intubation is a marker for AAA and may not represent a failure to maximize preintubation
therapies. AAA represents a distinct form of life-threatening
asthma and requires additional study in children.