Comparison of chronic illness among children receiving mechanical ventilation in a cohort of children's hospitals in 1991 and 2001

Objective: To compare the prevalence of chronic illness and characteristics of children who underwent mechanical ventilation in a cohort of patients at large children's hospitals between 1991 and 2001. Study design: This was a retrospective, cross-sectional study using the National Association of Children's Hospitals and Related Institutions (NACHRI) case mix database to identify children who underwent mechanical ventilation and compare the prevalence of chronic illness and incidence of mechanical ventilation. Results: The proportion of children who underwent mechanical ventilation who had at least 1 chronic condition increased from 72% in 1991 to 75% in 2001. The incidence of mechanical ventilation in hospitalized children almost doubled during this decade, from 77 per 1000 hospitalizations in 1991 to 124 per 1000 in 2001. The rate of mechanical ventilation increased with increasing numbers of chronic conditions. The mortality of children who underwent mechanical ventilation decreased from 14% in 1991 to 11% in 2001. Conclusions: The increase in mechanical ventilation in hospitalized children is due to both an increased incidence of chronic illness and higher use within diagnostic categories. Unlike utilization of some services, the use of mechanical ventilation in hospitalized children may be a marker of increased severity of illness and need, because it is plausible that mechanical ventilation use is not primarily supply-sensitive.