Setting of noninvasive pressure support in young patients with cystic fibrosis.

The aim of the current study was to compare a clinical noninvasive method of setting up noninvasive pressure support ventilation (PS-NI) in young patients with cystic fibrosis (CF), based on parameters such as breathing frequency, arterial oxygen saturation and comfort rating, with a more invasive method (PS-I) targeted at optimising unloading of the inspiratory muscles and enhancing patient-ventilator synchronisation. PS-NI and PS-I were compared in random order in 10 children with CF. PS-NI differed from PS-I with regard to the level of inspiratory pressure (n=5), rate of inspiratory pressurisation (n=1), inspiratory trigger sensitivity (n=2) and expiratory trigger sensitivity (n=5). Although both methods modified breathing pattern, improved oxygen saturation and reduced diaphragmatic pressure time product (450+/-91 cmH2O.s(-1).min(-1) during spontaneous breathing, and 129+/-125 and 104+/-75 cmH2O.s(-1).min(-1) during PS-NI and PS-I, respectively), patient-ventilator synchrony and patient comfort were enhanced more during PS-I. In young patients with cystic fibrosis, setting up pressure support using a clinical noninvasive approach based on easily measurable parameters, such as respiratory rate and comfort rating, is as effective as a more invasive technique based on unloading of the inspiratory muscles and optimising patient-ventilator synchronisation. However, whilst the standard clinical method is satisfactory in the majority of patients, more invasive measurements should be considered in patients who have difficulty synchronising with the ventilator to enhance patient tolerance and compliance.