Importance of different working principles

The influence of the different working principles of pressure support ventilation on respiratory muscle unloading should be considered. Different forms of inspiratory flow ramp, cycling criteria, and the flow-impeding characteristics of expiratory circuits induce important clinical changes in the external work of breathing. A ventilator algorithm providing a rapidly ascending inspiratory flow, thus generating a rapid velocity of pressurization, with a cycling criteria at 25 per cent of peak inspiratory flow has been proved more useful in terms of respiratory muscle unloading than those ventilator algorithms which provide a slowly increasing inspiratory flow ramp with cycling criteria near zero flow (Mancebo..et..al 1995). To provide an optimal reduction in inspiratory muscle effort, high inspiratory airflow rates should probably be mandatory to match adequately the patient's demands for flow.

Many factors related to pressure support ventilation tend to improve the synchrony between the patient's effort and ventilator support. However, this aspect is far from optimal; episodes of dyssynchrony have also been described. These include ineffective efforts at high levels of support, dyssynchrony at the end of inspiration, or insufficient flow during inspiration.

Sleep Apnea

Sleep Apnea

Have You Been Told Over And Over Again That You Snore A Lot, But You Choose To Ignore It? Have you been experiencing lack of sleep at night and find yourself waking up in the wee hours of the morning to find yourself gasping for air?

Get My Free Ebook


Post a comment