NON INVASIVE MECHANICAL VENTILATION IN SEVERE CHRONIC OBSTRUCTIVE LUNG-DISEASE AND ACUTE RESPIRATORY-FAILURE - SHORT AND LONG-TERM PROGNOSIS

Objective: To evaluate the short- and long-term prognosis of patients with chronic obstructive lung disease (COLD) who had noninvasive mecha nical ventilation (NMV) for acute respiratory failure (ARF). Design: R etrospective study. Setting: Two respiratory intermediate intensive ca re units. Patients: Two groups of patients suffering from COLD and an ARF episode requiring mechanical ventilation. Group 1 (30 patients) wa s given NMV using face masks (aged 64 +/- 9 years; pH = 7.28 +/- 0.05; PaCO2 = 83 +/- 18 mmHg; PaO2/FIO2 = 141 +/- 61). Group 2 (27 patients ) was composed of control patients (aged = 65 +/- 8 years; pH = 7.26 /- 0.05; PaCO2 = 75 +/- 17 mmHg; PaO2/FIO2 = 167 +/- 41) given MV usin g endotracheal intubation (EI) when clinical and functional conditions had further deteriorated because the medical therapy failed and NMV w as not available at the time. Causes of ARF were in group 1 and 2 resp ectively: pneumonia in 8 (27%) and 11 (41%), acute exacerbation of COL D in 19 (63%) and 14 (52%) and pulmonary embolism in 3 (10%) and 2 (7% ) patients. Measurements and results: Success rate, mortality during s tay in ICU (at 3 months and at 1 year), and the need for rehospitaliza tion during the year following ARF were measured in this study. Group 1 showed a success rate of 74%, only 8/30 patients needing EI and conv entional MV. In group 2, the weaning success was 74% (20/27 patients). The mortality for group 1 was 20% in IICU, 23% at 3 months and 30% at 1 year; and 26% for group 2 in ICU, 48% at 3 months and 63% at 1 year . Within each group 1-year mortality was greater (p < 0.01) in patient s with pneumonia. The number of new ICU admissions during the follow-u p at 1 year was 0.12 versus 0.30 in groups 1 and 2 respectively (p < 0 .05). Conclusion. For patients suffering from COLD who have undergone ARF, avoiding EI by early treatment with NMV is associated with better survival in comparison to patients bound to invasive MV. Pneumonia as a cause of ARF may worsen the prognosis in both groups of patients.