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Semin Respir Crit Care Med 2001; 22(2): 137-152
DOI: 10.1055/s-2001-13828
Copyright © 2001 by Thieme Medical Publishers, Inc., 333 Seventh Avenue, New York, NY 10001, USA. Tel.: +1(212) 584-4662

Optimizing Patient-Ventilator Synchrony

Scott K. Epstein
  • Pulmonary and Critical Care Division, New England Medical Center, Boston, Massachusetts
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Publication History

Publication Date:
31 December 2001 (online)

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ABSTRACT

Mechanical ventilation assumes the work of breathing, improves gas exchange, and unloads the respiratory muscles, all of which require good synchronization between the patient and the ventilator. Causes for patient-ventilator dyssynchrony include both patient factors (abnormalities of respiratory drive and abnormal respiratory mechanics) and ventilator factors (triggering, flow delivery, breath termination criteria, the level and mode of ventilator support, and imposed work of breathing). Although patient-ventilator dyssynchrony can often be detected on physical exam, careful analysis of ventilator waveforms (pressure-time, flow-time) allows for more precise definition of the underlying cause. Patient-ventilator interaction can be improved by reversing patient factors that alter respiratory drive or elevate patient ventilatory requirements and by correcting factors that contribute to dynamic hyperinflation. Proper setting of the ventilator using sensitive triggering mechanisms, satisfactory flow rates, adequate delivered minute ventilation, matching machine TI to neural TI, and applying modes that overcome the imposed work of breathing, further optimize patient-ventilator synchrony.

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