X3.2 Non-invasive positive pressure ventilation

Non-invasive ventilation reduces mortality and intubation rates in acute hypercapnic ventilatory failure (Osadnik 2017) [evidence level I]

Non-invasive ventilation (NIV) should be strongly considered in patients with an exacerbation of COPD who present with hypercapnic respiratory failure as defined on an arterial blood gas with a PaCO2 above 45mmHg and a pH less than 7.35 (Osadnik 2017) [evidence level I].

NIV is an effective and safe means of treatment of ventilatory failure. Its use allows preservation of cough, physiological air warming and humidification, and normal swallowing, feeding and speech. Applying NIV in addition to conven­tional therapy reduces the risk of mortality by 46% (risk ratio (RR) 0.54, 95% confidence interval (CI) 0.38 to 0.76); NNT 12 and decreases the risk of needing endotracheal intubation by 65% (RR 0.36, 95% CI 0.28 to 0.46; NNT 5) (Osadnik 2017). This benefit is similar for patients with mild acidosis (pH 7.30 to 7.35) versus a more severe nature (pH < 7.30), and when NIV is applied in a ward or intensive care unit (Osadnik 2017). The use of NIV reduces hospital length of stay mean difference -3.39 days (95% CI -5.93 to -0.85) (Osadnik 2017).

A local prospective observational cohort study demonstrated that ward-based NIV (managed by respiratory medical and nursing staff) compared with high dependency unit (HDU) and ICU-based NIV achieved equivalent clinical outcomes and was substantially more cost-effective (Parker 2018).  The optimal location for provision of NIV should be determined by local experience and availability of expertise.