[Intermittent self-ventilation after respirator weaning]

Weaning from the mechanical ventilator often proves to be difficult after prolonged ventilation due to excessive load or decreased capacity of the respiratory muscles. In the present retrospective study we examined the impact of the nocturnal mechanical ventilation during the "post-weaning-period" of long-term ventilated patients.

We studied 43 patients (23 men, 59.1 +/- 14.6 years) with chronic respiratory failure who were transmitted from external ICUs after a mechanical ventilation period of 57.5 +/- 60.3 days. The weaning regime consisted of an individually adapted volume-cycled ventilation. If the patients were hypercapnic (pCO2 > 48 mm Hg) after the first 24-hour-period of spontaneous breathing without supplemental oxygen nocturnal mechanical ventilation was initiated.

In a retrospective study we could show that the decision to initiate invasive or noninvasive nocturnal mechanical ventilation after successful weaning primarily depends on the question whether a chronic hypercapnic respiratory failure persisted also after weaning from long-term mechanical ventilation. In about 40% of unselected patients nocturnal mechanical ventilation stabilized the weaning success whereas 60% of the patients did not need any further nocturnal mechanical ventilation.