Diaphragmatic dysfunction in mechanical ventilation.

PURPOSE OF REVIEW: It has become clear from experimental data that prolonged mechanical ventilation can induce diaphragm dysfunction, also known as ventilator-induced diaphragm dysfunction. In this article we will discuss most recent understanding on ventilator-induced diaphragm dysfunction and data on diaphragm dysfunction in patients.

RECENT FINDINGS: Over the last year several studies confirmed the existence of diaphragm dysfunction in patients. Known atrophy pathways are activated in patients undergoing prolonged conventional ventilation resulting in muscle proteolysis and a decrease in myofiber content. The loss of diaphragm force is time-dependent, but current data do not distinguish between the role played by other factors involved in diaphragm dysfunction.

SUMMARY: Diaphragm dysfunction occurs in patients, especially when ventilated with controlled modes of ventilation that minimize diaphragm activity. Time on the ventilator seems to be one of the biggest risk factors resulting in difficulties in weaning patients and prolonging time on the ventilator. Future trials should investigate whether improved patient-ventilator synchrony can reduce ventilator-induced diaphragm dysfunction and decrease weaning failure.