A 10-year study has identified several factors that are independent predictors of hospital mortality in critically ill patients with severe chronic obstructive pulmonary disease (COPD). These factors include a patient’s age, the need for mechanical ventilation, and disease severity, the study shows.
The research, titled “Factors associated with hospital mortality in critically ill patients with exacerbation of COPD,” was published in the International Journal of Chronic Obstructive Pulmonary Disease.
Scientists have long known of the association between COPD and high mortality and morbidity rates, especially after a sudden worsening of the disease. Worsening episodes of COPD frequently result in admission to intensive care units (ICU). There, in-hospital mortality rates associated with the disease range from 11 to 48 percent.
A missing piece of the puzzle is the identification of factors that can reliably predict the outcomes of patients admitted to the ICU, with conflicting data being reported by the medical community.
To help solve the puzzle, researchers from Melbourne, Australia, attempted to identify factors that are linked to hospital mortality in COPD patients admitted to the ICU with a sudden worsening of symptoms.
Patients were retrospectively identified from ICU databases at the Frankston Hospital in Melbourne, Australia, from January 2005 to June 2016. A total of 305 COPD patients with a mean age of 67.4 years were included in the study.
Results showed that 77 percent of the patients required noninvasive ventilation, while 38.7 percent required invasive mechanical ventilation (IMV). One-fifth (20.5 percent) of the patients were being managed on home oxygen before the hospital admission.
Interestingly, a higher in-hospital mortality rate was seen in patients who often required IMV. Also, those who died during hospital admission were more likely to have worse COPD symptoms and to have been on home oxygen.
Results also showed that patients with COPD spent more time in the hospital (a mean of 11.6 days) than in the ICU (4.5 days). Mortality was higher in the hospital (18.7 percent) than in the ICU (11.5 percent).
Higher levels of carbon dioxide in the blood (demonstrating poor oxygenation), more white blood cells (associated with infection), and lower blood pressure were seen in patients who died compared with those who survived, suggesting that deceased patients had a more severe form of COPD.
Overall, researchers identified factors significantly associated with in-hospital mortality in patients admitted to ICU for acute exacerbations of COPD, namely the patient’s age, the need for IMV rather than noninvasive methods, and disease severity, as measured by the Acute Physiology and Chronic Health Evaluation (APACHE)-II score and ICU/hospital length of stay.
“Mortality from COPD remains high, and exacerbations of COPD are a significant cause of hospitalization and ICU admission,” the researchers wrote.