The epidemiology and outcome of medical emergency team call patients treated with non-invasive ventilation.

Introduction: Use of non-invasive ventilation (NIV) is normally limited to the Emergency Department, Intensive Care Unit (ICU), Coronary Care Unit (CCU) or High Dependency Unit (HDU). However, NIV is sometimes used by the Medical Emergency Team (MET) as respiratory support for ward patients.

Objectives: We reviewed the characteristics and outcome of ward patients treated with NIV in the setting of a MET Call and determined the clinical and prognostic significance of such treatment.

Methods: We used our MET database to assess the characteristics and outcome of patients treated with NIV and compared them to a control group of patients with similar MET diagnoses but not treated with NIV.

Results: We studied 5389 calls in 3880 patients. NIV was delivered during 483 (9.0%) calls to 426 patients (11% of the total). The four most common MET diagnoses associated with NIV were acute pulmonary edema (156 calls, 32.3%), pneumonia (84 calls, 17.4%), acute respiratory failure of unclear origin (59 calls, 12.2%) and exacerbation of chronic obstructive pulmonary disease (32 calls, 6.6%). Limitations of medical therapy (LOMT) were documented in 151 (35.4%) patients. Among NIV patients without LOMT, 115 (41.8%) were transferred to ICU and 50 (18.2%) to the coronary care or high dependency unit (CCU/HDU) compared with only 50 (18.0%) and 16 (5.8%) respectively in the control group (p<0.001). Overall, 76 NIV patients (27.6%) received endotracheal intubation (ETT) compared with 61 (21.9%) in controls. Mortality was 23.6% in the NIV group versus 18.8% in the control group.

Conclusion: One in ten MET call patients received NIV. In those without LOMT, two thirds were transferred to ICU/HDU/CCU, one in four received ETT, and one in four died. NIV use at the time of a MET call identified high risk patients for whom admission to ICU/HDU/CCU should be strongly considered.