THE EFFECTS OF 5 YEARS OF NOCTURNAL CUIRASS-ASSISTED VENTILATION IN CHEST-WALL DISEASE

We investigated the long-term effectiveness of cuirass-assisted ventil ation, and examined whether mortality and morbidity could have been pr edicted at the time of admittance. Twenty five patients were commenced on nocturnal cuirass-assisted ventilation between 1983 and 1985, 10 w ith scoliosis or kyphosis, 8 with a thoracoplasty and 7 with neuromusc ular disease. Mean pretreatment vital capacity was 30% of predicted, a nd arterial carbon dioxide tension (Paco2) was 8.2 kPa (62 mmHg). Fift een patients were alive 5 yrs later. Two had discontinued assisted ven tilation, both dying soon afterwards, and three had been changed to in termittent positive pressure ventilation. Survival could not have been predicted from age, severity of disease, tung volumes or arterial blo od gases at presentation. Paco2 in the survivors had risen from a mean of 6.1 kPa (46 mmHg) after one year to 6.8 kPa (52 mmHg) after 5 yrs (p<0.05), but remained significantly less than at presentation. There were no significant change in arterial oxygen tension (Pao2), lung vol umes, respiratory muscle strength, haemoglobin, right heart failure, e xercise tolerance, mental function and symptom scores after 5 yrs, com pared to after 1 yr. The median amount of time spent in hospital decli ned from 15 days per patient in the first year after initial discharge with cuirass-assisted ventilation, to between 3-5.5 days per patient tn subsequent years. We conclude that nocturnal cuirass-assisted venti lation has a role in long-term management of patients with neuromuscul ar and skeletal chest wall disorders. A randomized comparison with nas al intermittent positive pressure ventilation is now indicated.