The Science Journal of the American Association for Respiratory Care

2008 OPEN FORUM Abstracts

EPIDEMIOLOGY OF NONINVASIVE MECHANICAL VENTILATION FOR ACUTE RESPIRATORY FAILURE IN OLMSTED COUNTY, MINNESOTA: A RETROSPECTIVE POPULATION-BASED STUDY

Guangxi Li1, Marija Kojicic1, Suri Harpreet1, Rodrigo Cartin-Ceba1, Ognjen Gajic1



Background: Noninvasive ventilation (NIV) has been increasingly used in treatment of acute respiratory failure (ARF) but the need for NIV in a defined community is not known. The aim of this study was to determine the utilization and outcome of NIV in the community of Olmsted County, Minnesota in 2006, where Mayo Clinic serves as the only center capable of providing intensive care services.

Methods: Retrospective cohort study was performed in adult (?18 years) Olmsted county residents admitted to any Mayo Clinic ICU during 2006. ARF was defined by the acute need of invasive mechanical ventilation (MV) support for more than 12 hours or NIV for more than 1 hour. Continuous Positive Airway Pressure (CPAP) or Bilevel Positive Airway Pressure (BiPAP) were both considered as modes of NIV. Individuals who denied research authorization and patients who use chronic NIV treatment for sleep apnea were excluded.

Results: A total of 1461 Olmsted County adult residents were admitted to the ICU, of whom 299 patients developed 342 episodes of respiratory failure and were ventilated in ICU yielding a cumulative incidence of 340 episodes per 100,000 person-years (95%CI 306~378/100,000). NIV was used in 79 patients for 91 (26.6%) episodes of respiratory failure. Median age was 70 (IQR 59-79), 49.3% were male, 88.6% Caucasians. BiPAP was applied in 73(70.2%) episodes and CPAP in 18(19.8%). NIV was used as weaning process in 20(5.8%) episodes and for initiation of ventilation in 73 (21.3%) episodes of ARF. NIV was successful in 45(54.8%) attempts. Of 33 (45.2%) patients who failed NIV, 15 died (do not resuscitate status) and 18 underwent invasive mechanical ventilation. Mortality was similar in patients initially supported with NIV vs invasive mechanical ventilation (21.9% vs 20.1%, P=0.752).

Conclusion: NIV is commonly used as initial treatment of ARF in the community. The utilization of NIV and success of treatment is higher than previously reported possibly due to referral bias.