The use of non-invasive ventilation (NIV) for acute respiratory failure outside the intensive care unit (ICU) is common in some hospitals. This study aims to evaluate the outcomes of episodes of acute respiratory failure (ARF) treated by NIV in a dedicated “sub-ICU” unit in comparison to the treatment of such cases in general wards (GW) of the hospital.
We assessed the severity of disease and the rates of NIV success of 121 patients with ARF treated in the non-invasive ventilation unit (NIVU) and compared these with 46 historical controls treated in the GW. The NIVU is a 4-bedded unit with a 1:4 nurse:patient ratio largely devoted to NIV treatment of ARF, that was opened in 2001 in response to increasing frequency of NIV treatment in GW due to unavailability of intensive care beds. GW nurses with minimal previous training in NIV flexibly staffed the NIVU and were supported by respiratory therapists.
The commonest causes of ARF treated in the NIVU were decompensated COPD (67.5%), obesity-hypoventilation syndrome (6.7%), bronchiectasis (5.8%), and pneumonia (9.2%). There was no significant difference between the mean baseline pH among cases treated in NIVU and controls (7.27 vs 7.27; P=0.811). However, the mean baseline PaCO2 was significantly higher in NIVU cases than controls (86.4mmHg vs 68.3mmHg respectively; P=0.028). The rate of NIV success in the NIVU was significantly higher than controls (82.9% vs 52.2% respectively; P<0.001). There were 21 cases of deaths (17.4%) in the NIVU compared to 19 (41.3%) among the controls (P=0.002).
Outside the ICU, the rate of success with NIV treatment of ARF in a dedicated unit can be significantly higher compared to isolated cases treated in general wards.
With the increasing practice of NIV outside the ICU in some hospitals, consideration should be made to concentrate medical, nursing and equipment resources in a dedicated unit as this may lead to significant improvement in outcomes with minimal additional expenditure.
K.C. Ong, None.