The Effect of Clusters of Double Triggering and Ineffective Efforts in Critically Ill Patients

Abstract

OBJECTIVES: 

To characterize clusters of double triggering and ineffective inspiratory efforts throughout mechanical ventilation and investigate their associations with mortality and duration of ICU stay and mechanical ventilation.

DESIGN: 

Registry-based, real-world study.

Background: 

Asynchronies during invasive mechanical ventilation can occur as isolated events or in clusters and might be related to clinical outcomes.

Subjects: 

Adults requiring mechanical ventilation greater than 24 hours for whom greater than or equal to 70% of ventilator waveforms were available.

INTERVENTIONS: 

We identified clusters of double triggering and ineffective inspiratory efforts and determined their power and duration. We used Fine-Gray’s competing risk model to analyze their effects on mortality and generalized linear models to analyze their effects on duration of mechanical ventilation and ICU stay.

MEASUREMENTS AND MAIN RESULTS: 

We analyzed 58,625,796 breaths from 180 patients. All patients had clusters (mean/d, 8.2 [5.4–10.6]; mean power, 54.5 [29.6–111.4]; mean duration, 20.3 min [12.2–34.9 min]). Clusters were less frequent during the first 48 hours (5.5 [2.5–10] vs 7.6 [4.4–9.9] in the remaining period [p = 0.027]). Total number of clusters/d was positively associated with the probability of being discharged alive considering the total period of mechanical ventilation (p = 0.001). Power and duration were similar in the two periods. Power was associated with the probability of being discharged dead (p = 0.03), longer mechanical ventilation (p < 0.001), and longer ICU stay (p = 0.035); cluster duration was associated with longer ICU stay (p = 0.027).

CONCLUSIONS: 

Clusters of double triggering and ineffective inspiratory efforts are common. Although higher numbers of clusters might indicate better chances of survival, clusters with greater power and duration indicate a risk of worse clinical outcomes.