ICU Utilization for Patients With Acute Exacerbation of Chronic Obstructive Pulmonary Disease Receiving Noninvasive Ventilation

Abstract

Objectives: We investigated whether patients with chronic obstructive pulmonary disease could safely receive noninvasive ventilation outside of the ICU.

Design: Retrospective cohort study.

Setting: Twelve states with ICU utilization flag from the State Inpatient Database from 2014.

Patients: Patients greater than or equal to 18 years old with primary diagnosis of acute exacerbation of chronic obstructive pulmonary disease and secondary diagnosis of respiratory failure who received noninvasive ventilation.

Interventions: None.

Measurements and main results: Multilevel logistic regression models were used to obtain hospital-level ICU utilization rates. We risk-adjusted using both patient/hospital characteristics. The primary outcome was in-hospital mortality; secondary outcomes were invasive monitoring (arterial/central catheters), hospital length of stay, and cost. We examined 5,081 hospitalizations from 424 hospitals with ICU utilization ranging from 0.05 to 0.98. The overall median in-hospital mortality was 2.62% (interquartile range, 1.72-3.88%). ICU utilization was not significantly associated with in-hospital mortality (β = 0.01; p = 0.05) or length of stay (β = 0.18; p = 0.41), which was confirmed by Spearman correlation (ρ = 0.06; p = 0.20 and ρ = 0.02; p = 0.64, respectively). However, lower ICU utilization was associated with lower rates of invasive monitor placement by linear regression (β = 0.05; p < 0.001) and Spearman correlation (ρ = 0.28; p < 0.001). Lower ICU utilization was also associated with significantly lower cost by linear regression (β = 14.91; p = 0.02) but not by Spearman correlation (ρ = 0.09; p = 0.07).

Conclusions: There is wide variability in the rate of ICU utilization for noninvasive ventilation across hospitals. Chronic obstructive pulmonary disease patients receiving noninvasive ventilation had similar in-hospital mortality across the ICU utilization spectrum but a lower rate of receiving invasive monitors and probably lower cost when treated in lower ICU-utilizing hospitals. Although the results suggest that noninvasive ventilation can be delivered safely outside of the ICU, we advocate for hospital-specific risk assessment if a hospital were considering changing its noninvasive ventilation delivery policy.

Figure 1.

Loess plot of adjusted hospital-level ICU utilization and hospital mortality.

Figure 2.

Loess plots of adjusted hospital-level ICU utilization and (A) invasive monitoring, (B) length of stay, and (C) cost. Invasive monitoring includes both central and arterial catheters. Cost is per hospitalization.