FIG. 3: To understand the background for the HOT-HMV trial of HMV in COPD, it is important to realize the scope of the problem. COPD is a common medical problem, accounting for approximately 20% of all general medical admissions, both in the United States and in the UK; significant numbers of those patients have respiratory failure and many of these require ventilatory support.[2]

Those patients requiring ventilatory support have high rates of readmission (approximately a third at 90 days), and >80% of patients who have an admission with an exacerbation of COPD requiring ventilatory support are readmitted within the subsequent year.

There is also significant mortality associated with acute exacerbations of COPD, both acutely as an inpatient and over the following 90 and 365 days.