Ventilation Rates and Pediatric In-Hospital Cardiac Arrest Survival Outcomes

Abstract

Objectives: The objective of this study was to associate ventilation rates during in-hospital cardiopulmonary resuscitation with 1) arterial blood pressure during cardiopulmonary resuscitation and 2) survival outcomes.

Design: Prospective, multicenter observational study.

Setting: Pediatric and pediatric cardiac ICUs of the Collaborative Pediatric Critical Care Research Network.

Patients: Intubated children (≥ 37 wk gestation and < 19 yr old) who received at least 1 minute of cardiopulmonary resuscitation.

Interventions: None.

Measurements and main results: Arterial blood pressure and ventilation rate (breaths/min) were manually extracted from arterial line and capnogram waveforms. Guideline rate was defined as 10 ± 2 breaths/min; high ventilation rate as greater than or equal to 30 breaths/min in children less than 1 year old, and greater than or equal to 25 breaths/min in older children. The primary outcome was survival to hospital discharge. Regression models using Firth penalized likelihood assessed the association between ventilation rates and outcomes. Ventilation rates were available for 52 events (47 patients). More than half of patients (30/47; 64%) were less than 1 year old. Eighteen patients (38%) survived to discharge. Median event-level average ventilation rate was 29.8 breaths/min (interquartile range, 23.8-35.7). No event-level average ventilation rate was within guidelines; 30 events (58%) had high ventilation rates. The only significant association between ventilation rate and arterial blood pressure occurred in children 1 year old or older and was present for systolic blood pressure only (-17.8 mm Hg/10 breaths/min; 95% CI, -27.6 to -8.1; p < 0.01). High ventilation rates were associated with a higher odds of survival to discharge (odds ratio, 4.73; p = 0.029). This association was stable after individually controlling for location (adjusted odds ratio, 5.97; p = 0.022), initial rhythm (adjusted odds ratio, 3.87; p = 0.066), and time of day (adjusted odds ratio, 4.12; p = 0.049).

Conclusions: In this multicenter cohort, ventilation rates exceeding guidelines were common. Among the range of rates delivered, higher rates were associated with improved survival to hospital discharge.

Figure 1.

Scatterplot of minute-level average ventilation rates versus diastolic (A and B) and systolic (C and D) blood pressures (BPs). Children less than 1 yr old (A and C), and older children greater than or equal to 1 yr old (B and D). Estimates for slope represent change in BP for each 10 breaths/min (bpm) increase in ventilation rate. All estimates from generalized estimating equations to control for minutes within a cardiopulmonary resuscitation event for the same patient.

Figure 2.

Evaluation of optimal ventilation rates using receiver operating characteristic area under the curve (AUC; A and B) and cubic spline analysis (C and D). Children less than 1 yr old (A and C), and older children greater than or equal to 1 yr old (B and D). Solid line in AUC analysis signifies the predicted survival rate, whereas the dotted line represents the 95% CI. bpm = breaths/min, Cut = optimal cut point, Sens = sensitivity, Spec = specificity.