Survival in intensive care of patients with chronic obstructive bronchopneumopathy and acute respiratory failure undergoing mechanical ventilation. Retrospective study

OBJECTIVE. To collect valuable informations for the evaluation of the patients' clinical evolution and to perform a cost-effectiveness analysis on the utilization of resources in the management of patients with chronic obstructive pulmonary disease (COPD) undergoing mechanical ventilation (MV) for acute respiratory failure (ARF). SETTING. General ICU. University Hospital. PATIENTS. 87 BPCO patients (mean age: 69.6 +/- 8.5) undergoing MV for ARF due to non surgical or traumatic events, for a total of 108 consecutive ICU admissions between January 1983 and December 1993. METHODS. Retrospective study in which the following data were collected: severity of the underlying chronic respiratory disease before the occurrence of ARF. For this aim patients have been divided into five classes (O-IV) according with ATS classification of dyspnea; causes of ARF; SAPS score; TISS score; OMEGA score; complications occurred in ICU; duration of MV; duration of stay in ICU; ICU and hospital outcome. RESULTS. In 48 cases (44.4%) clinical history was positive for a severe dyspnea (classes III-IV). Slight airway flogosis or infection were responsible of ARF in 78 cases; pneumonia was present in 24 cases while in 6 cases ARF was due to congestive heart failure. The study population was divided into two groups according with outcome. No statistically significant difference was observed in mean SAPS and TISS scores between the two groups (12.5 +/- 3 vs 13 +/- 4.8 and 18.4 +/- 2.3 vs 19 +/- 4.2). Mean OMEGA score was 155 +/- 11.7 (ES). With reference to ICU outcome the utilization rate or resources was 72.15% with a mean loss of resources of 43.2. Compli-cations were manly due to airway infection (16 cases) which was responsible in one case of the patient's death. Overall incidence of complications was relatively low and five of them led to patients' death in ICU. Mean duration of MV did not differ between the two groups (13.4 +/- 11.7 vs 14.3 +/- 11.7) but it was significantly longer in those patients whose clinical history was positive for severe dyspnea (classes III and IV) than in patients without this report (16.6 +/- 14.9 vs 10.9 +/- 6.9; p < 0.05). Mean stay in ICU did not differ significantly between survivors and non-survivors (21.4 +/- 18.6 vs 19.7 +/- 13). ICU mortality rate was 6.48% (7 patients) and hospital mortality rate was 20.3% (22 patients). CONCLUSIONS. Our results demonstrate that hospital outcome in COPD patients with ARF requiring mechanical ventilation is quite good. Prolonged mechanical ventilation and--severity of underlying chronic respiratory disease do not affect significatively the prognosis. The high costs of the treatment of these patients are counterbalanced by a good efficiency of utilization of resources and appreciable clinical results