[Noninvasive ventilation in acute respiratory insufficiency]

Abstract

Background and aim: Noninvasive positive pressure ventilation (NPPV) via face mask offers in comparison to endotracheal intubation in treating patients with acute respiratory failure (ARF) advantages like allowing swallowing and coughing. We report our experiences and try to verify the indications and the efficacy of NPPV.

Patients and methods: In the period of January 1991 until August 1996 109 patients (30 female, 79 male, mean age 61 +/- 12 years) received mechanical ventilation with NPPV representing 25% of all MVs in this term. As baseline capillary blood gases (CBG) were found: pH: 7.30 +/- 0, 10; pCO2: 64 +/- 19; pO2: 60 +/- 19 (all patients received supplemental oxygen). Success of NPPV was determined by an improvement of the baseline CBG.

Results: NPPV was successful in 77 (71%) patients. Considering the kind of respiratory insufficiency the patient population was divided into 4 groups 1. acute hypoxemic respiratory failure, 2. acute hypercapnic ventilatory failure, 3. acute decompensation of chronic respiratory insufficiency (CRI) and 4. combined failure. Considering these subgroups we obtained the best results in the group of patients with hypercapnic disturbances. In patients with hypoxemic RF we observed a success of NPPV if the improvement of CBG occurred in the early stage (< or = 12 hours) of NPPV.

Conclusion: Our data indicate that application of NPPV is an effective and safe alternative to endotracheal intubation in many patients with hypercapnic ventilatory failure. NPPV is also successful in patients with hypoxemic RF with a milder course.