A new study finds that while increased use of noninvasive positive-pressure ventilation (NIPPV) nationwide has helped decrease mortality rates among patients hospitalized with chronic obstructive pulmonary disease (COPD), a small group of patients requiring subsequent treatment with invasive mechanical ventilation (IMV) have a significantly higher risk of death than those placed directly on IMV. The findings appear in the American Thoracic Society’s American Journal of Respiratory and Critical Care Medicine.

Analyzing clinical patient data gathered by the Healthcare Cost and Utilization Project Nationwide Impatient Sample (HCUP-NIS) database between 1998 and 2008, the researchers examined changes in frequency of NIPPV and IMV use and compared patient demographics, income status, payor type, hospital region and hospital type among patients who initially received NIPPV, IMV, or no respiratory support after hospital admission. They also examined in-hospital mortality, length-of-stay, and total hospitalization charges, and compared those outcomes among patient groups.

The researchers found that although the annual number of hospitalizations for acute exacerbations remained relatively constant during the 10-year period, there was a progressive increase in the use of NIPPV and a progressive decrease in use of IMV. During the entire study period, there was a fourfold increase in the use of NIPPV, which had grown to overtake IMV as the most frequently used form of respiratory support for patients hospitalized with acute exacerbations in the United States.

They also found that despite a steady decline in mortality among most patients studied, patients who used NIPPV and were then transitioned to IMV had significantly higher mortality rates than other patients, and that the mortality rate in these transitioned patients increased during the study period while mortality rates of other groups declines. Patients in this group also experienced the greatest increase in hospital charges and longest length-of-stay.

“The concerning finding in our analysis was the high mortality in the group of patients who, despite initial treatment with NIPPV, required subsequent placement on IMV,” said Fernando Holguin, MD, MPH, assistant professor of medicine at the University of Pittsburgh School of Medicine. “It is notable that this finding is contrary to that found in the carefully monitored patient environment of clinical trials, where those transitioned from NIPPV to IMV did not have higher mortality than patients placed on IMV from the beginning.”

Holguin added that the overall trend toward greater use of NIPPV was likely due to several factors, including clinical trials linking NIPPV with a decrease in hospital mortality, increased confidence in using NIPPV, and the ability to use NIPPV outside of the intensive care unit.

“These results suggest that healthcare providers should continue to be aggressive with the use of noninvasive ventilation for patients with acute exacerbations, but definitely should intensively monitor sick patients, intervene early in the absence of improvement, and carefully examine if transitioning to IMV is in the interest of a patient with a poor prognosis,” he said.

Source: American Thoracic Society