RATIONALE: The helmet is a new interface with the potential of increasing the success rate of non-invasive ventilation by improving tolerance. OBJECTIVES: To perform a physiological comparison between the helmet and the conventional facial mask in delivering non-invasive ventilation in hypercapnic patients with chronic obstructive pulmonary disease. METHODS: Prospective, controlled, randomized study with cross-over design. In 10[Symbol: see text]patients we evaluated gas exchange, inspiratory effort, patient-ventilator synchrony and patient tolerance after 30[Symbol: see text]min of non-invasive ventilation delivered either by helmet or facial mask; both trials were preceded by periods of spontaneous unassisted breathing. MEASUREMENTS: Arterial blood gases, inspiratory effort, duration of diaphragm contraction and ventilator assistance, effort-to-support delays (at the beginning and at the end of inspiration), number of ineffective efforts, and patient comfort. MAIN RESULTS: Non-invasive ventilation improved gas exchange (p<[Symbol: see text]0.05) and inspiratory effort (p<[Symbol: see text]0.01) with both interfaces. The helmet, however, was less efficient than the mask in reducing inspiratory effort (p<[Symbol: see text]0.05) and worsened the patient-ventilator synchrony, as indicated by the longer delays to trigger on (p<[Symbol: see text]0.05) and cycle off (p<[Symbol: see text]0.05) the mechanical assistance and by the number of ineffective efforts (p<[Symbol: see text]0.005). Patient comfort was no different with the two interfaces. CONCLUSIONS: Helmet and facial mask were equally tolerated and both were effective in ameliorating gas exchange and decreasing inspiratory effort. The helmet, however, was less efficient in decreasing inspiratory effort and worsened the patient-ventilator interaction.
|Number of pages||8|
|Journal||Intensive Care Medicine|
|Publication status||Published - 2006|
- Non invasive ventilation