Weaning from mechanical ventilation using assisted spontaneous breathing plus CPAP versus assisted spontaneous ventilation: our experience

Introduction

In this retrospective study, we evaluated two different modes of weaning: assisted spontaneous breathing (ASB) plus CPAP with automatic tube compensation (Evita 4, Draeger Medical, Germany) versus assisted spontaneous ventilation (ASV) (Galileo Gold, Hamilton Medical, Switzerland) in 80 patients who had undergone abdominal surgery. Our target was to assess differences in weaning times using different modes of assistance.

Methods

Forty patients were enrolled in two groups of weaning: group A was treated with ASB and CPAP, and group B was treated with ASV. Both groups after mechanical support underwent a 2-hour T-tube ventilation before extubation and were sedated with remifentanil beginning from 6 μg/kg/hour and titrated to reach the Ramsay sedation scale 3–4 without the help of other drugs; supplemental midazolam bolus was administered if the patients were still agitated. The time of weaning and other events during ASB or ASV (discomfort during ventilation, bad-adaptation) were recorded in each patient.

Results

We did not find a great statistical difference among the two groups (20 ± 10.75 vs 21.6 ± 8.46, P = 0.3). We had three cases of weaning failure with ASB and CPAP and five with ASV after 30–36 hours from extubation. If the ventilator setting was done following the patient requests, few signs of discomfort were found (agitation, tachycardia, hypertension, etc.) and a good patient–ventilator interaction can be granted using both methods of ventilatory support.

Conclusion

We did not find any statistical difference in the two groups: times for weaning were almost the same. Our data cannot suggest the use of a specific modality of weaning, because the number of patients in the study is too small. But both ways of assistance were well tolerated by the patients.