Studies in developed countries have shown that between 23 and 40 % of children in the pediatric intensive care unit (PICU) receive mechanical ventilator support at some point during their PICU stay (Dahlem et al. 2003; Watson et al. 2002; Angus et al. 2001; Census 2002; Farias et al. 2006; Khemani et al. 2007). The weaning phase of mechanical ventilator support has been defined as the “transition from ventilatory support to complete spontaneous breathing while maintaining effective gas exchange” (Newth et al. 2009). Extubation is the physical removal of the endotracheal tube and is the endpoint of the weaning phase. On average, the weaning phase accounts for approximately 40 % of the total duration of mechanical ventilation in children (Newth et al. 2009; MacIntyre 2001).