Covariates
Demographic and patient characteristics that might influence 3-year respiratory support needs, decannulation, and death were obtained from the EMR including age, sex, race, ethnicity, insurance type, comorbid diagnoses, and home ventilator use. Sex, race, and ethnicity were included as covariates to describe the population and were not treated as biologic constructs. Encounter-level diagnoses were pooled across each child’s encounters over time and coded to identify complex chronic conditions (CCCs) using previously-defined ICD-9 and -10 codes.22 Home ventilator use was defined at the time of first Pulmonary visit after hospital discharge as the requirement, when well, for mechanical ventilation for any portion of the day/night and for any duration after initial discharge with tracheostomy until 3 years after placement. Initial hospital discharge typically occurs several months after tracheostomy placement at our institution.