Nocturnal deaths among patients with chronic bronchitis and emphysema

Abstract

Patients with chronic bronchitis and emphysema may develop episodes of severe hypoxaemia with associated ventricular arrhythmias during sleep. We examined the possibility that such nocturnal abnormalities predispose such patients to sudden death. Patients, methods, and results We studied patients who died in this hospital from chronic bronchitis and emphysema during 1977-81, excluding those with coexisting lung cancer. There were 54 such patients (42 men, 12 women), whose mean (SD) age was 71 (8.7) years. We also examined two control groups matched for age and sex, consisting of 54 patients who died from non-respiratory neoplasms and 54 who died from cerebrovascular disease. For analysis the day was divided into three periods of eight hours each: 11 pm to 7 am (night), 7 am to 3 pm (day), and 3 pm to 11 pm (evening). In this hospital patients are settled down to bed between 10 30 and 11 pm and woken up around 7 am. Thus the night period approximated to the expected period of sleep. There was no significant difference in the pattern of mortality over time between the two control groups, whereas most of the patients with chronic bronchitis and emphysema died at night (p<0.05, χ2 test). The highest mortality in these patients was in the first hour of the night (seven deaths). Furthermore, 11 patients died between 4 and 7 am, whereas only two died between 7 and 10 am. Age and sex had no influence on the incidence of nocturnal deaths. Our findings indicate that patients admitted to hospital with an acute exacerbation of chronic bronchitis and emphysema should be carefully monitored at night, particularly if they have hypercapnia. The findings als emphasise the importance of controlled low flow oxygen in such patients.