by Scott W. Ketcham, Yub Raj Sedhai, H. Catherine Miller,
Thomas C. Bolig, Amy Ludwig, Ivan Co, Dru Claar, Jakob I. McSparron, Hallie C.
Prescott and Michael W. Sjoding
Critical Care volume 24,
Article number: 391 (2020)
Background
Acute hypoxemic respiratory failure (AHRF) and acute
respiratory distress syndrome (ARDS) are associated with high in-hospital
mortality. However, in cohorts of ARDS patients from the 1990s, patients more
commonly died from sepsis or multi-organ failure rather than refractory
hypoxemia. Given increased attention to lung-protective ventilation and sepsis
treatment in the past 25 years, we hypothesized that causes of death may be
different among contemporary cohorts. These differences may provide clinicians
with insight into targets for future therapeutic interventions.
Methods
We identified adult patients hospitalized at a single
tertiary care center (2016–2017) with AHRF, defined as PaO2/FiO2 ≤ 300
while receiving invasive mechanical ventilation for > 12 h, who died during
hospitalization. ARDS was adjudicated by multiple physicians using the Berlin
definition. Separate abstractors blinded to ARDS status collected data on organ
dysfunction and withdrawal of life support using a standardized tool. The primary
cause of death was defined as the organ system that most directly contributed
to death or withdrawal of life support.
Results
We identified 385 decedents with AHRF, of whom 127 (33%) had
ARDS. The most common primary causes of death were sepsis (26%), pulmonary
dysfunction (22%), and neurologic dysfunction (19%). Multi-organ failure was
present in 70% at time of death, most commonly due to sepsis (50% of all
patients), and 70% were on significant respiratory support at the time of
death. Only 2% of patients had insupportable oxygenation or ventilation.
Eighty-five percent died following withdrawal of life support. Patients with
ARDS more often had pulmonary dysfunction as the primary cause of death (28% vs
19%; p = 0.04) and were also more likely to die while requiring
significant respiratory support (82% vs 64%; p < 0.01).
Conclusions
In this contemporary cohort of patients with AHRF, the most
common primary causes of death were sepsis and pulmonary dysfunction, but few
patients had insupportable oxygenation or ventilation. The vast majority of
deaths occurred after withdrawal of life support. ARDS patients were more
likely to have pulmonary dysfunction as the primary cause of death and die
while requiring significant respiratory support compared to patients without
ARDS.
