People display normal variability in their breathing patterns even at rest. In contrast, although a necessary medical intervention, mechanical ventilation uses some sort of fixed parameter in almost all currently available modes.
The best way to describe asynchrony is to call it poor patient-ventilator interaction. Patient-ventilator interaction is dependent upon many variables. Some of those are:
Asynchrony occurs at varying degrees depending on the patient population and the mechanical ventilation strategy employed. The most common types of asynchrony are ineffective efforts and double triggers.
Patient-ventilator asynchrony is typically uncomfortable for the patient. In addition, it may have an impact on patient outcomes. Epstein([FOOTNOTE=Sassoon C. Triggering of the ventilator in patient-ventilator interactions. Respiratory Care. 2011;56(1):39-51.],[ANCHOR=],[LINK=]) put together a list of adverse effects associated with poor patient-ventilator interaction:
Investigators have examined the relationship between patient-ventilator asynchrony and outcomes. Thille et al([FOOTNOTE=Thille AW et al. Patient-ventilator asynchrony during assisted mechanical ventilation. Intensive Care Med. 2006;32(10):1515-1522.],[ANCHOR=],[LINK=]) found patients with an asynchrony index >10% had a longer duration of mechanical ventilation and were more likely to need a tracheostomy. de Wit et al([FOOTNOTE=de Wit M. Monitoring of patient ventilator interaction at the bedside. Respiratory Care. 2011;56(1):61-68.],[ANCHOR=],[LINK=]) found that those patients who had an ineffective trigger index of >10% had a longer duration of mechanical ventilation, a worse 28-day ventilator-free survival, and a longer ICU time and hospital stay. Patients in the ineffective trigger group were less likely to be discharged to home. Varon et al([FOOTNOTE=Puritan Bennett™ 980 Ventilator Operator's Manual],[ANCHOR=],[LINK=]) found that mortality was higher in patients with an asynchrony index >30%.
You know us — and our innovations, which have been improving respiratory and monitoring care for over a century.
Puritan Bennett™ 980 Ventilator System Technical Specifications for Canada.
Explore additional resources, best practices, and insights for healthcare professionals.