Characteristics of children intubated and mechanically ventilated in 16 PICUs

Abstract

Background: When designing multicenter clinical trials, it is important to understand the characteristics of children who have received ventilation in PICUs.

Methods: This study involved the secondary analysis of an existing data set of all children intubated and mechanically ventilated from 16 US PICUs who were initially screened for a multicenter clinical trial on pediatric acute lung injury (ALI).

Results: A total of 12,213 children between 2 weeks and 18 years of age who were intubated and mechanically ventilated were included, representing 30% of PICU admissions (center range, 20 to 64%). Of the children who received ventilation, 22% had cyanotic congenital heart disease; 26% had respiratory failure but not bilateral pulmonary infiltrates on chest radiograph; 8% had chronic respiratory disease; 7% had upper airway obstruction; and 5% had reactive airway disease. At least 1,457 patients (15%) with respiratory failure lacked an arterial line. Of these patients, 97% had a positive end-expiratory pressure <or= 8 cm H(2)O, and 80% were supported on an Fio(2) of <or= 0.40. Moreover, 104 of 904 patients (12%) with pulse oximetric saturation (Spo(2)) and Fio(2) measurements available would have met the oxygenation criteria for ALI according to Spo(2)/Fio(2) ratio criteria.

Conclusions: At least 30% of children in a cross-section of US PICUs are endotracheally intubated, and 25% of those with respiratory failure do not fulfill the radiographic criteria for ALI. Although few patients without an indwelling arterial line require more than modest ventilator support, many may still meet the oxygenation criteria for ALI. These findings will facilitate sample size calculations and help to determine feasibility for future trials on pediatric mechanical ventilation.

Figure 1

Overall proportion of patients receiving mechanical ventilation by center. Of note, the proportion was calculated as the number of patients screened per the total number of PICU admissions over the given time period.

Figure 2

Top: distribution of PEEP for patients without arterial lines. Note that 97% of patients without arterial lines are managed with PEEP < 8. Bottom: distribution of PEEP by center. Note the similarity in median PEEP among all centers. For centers 1 to 5, 10, 11, and 15, the interquartile range values for PEEP were identical to the median values. Variability from analysis of variance (*) is predominantly due to mean ranks between centers 6 and 8 based on results of a Scheffé test for multiple comparisons.

Figure 3

Top: distribution of Fio₂ for patients without arterial lines. Note that 96% of patients are managed with Fio₂ < 0.5. Bottom: Fio₂ distribution by center. Note the similarity in median Fio₂ among all centers. Variability from analysis of variance (*) is predominantly due to mean ranks between centers 4 and 5 based on the results of a Scheffé test for multiple comparisons.