Impedance threshold device

An inspiratory impedance threshold device is a valve used in cardiopulmonary resuscitation (CPR) to decrease intrathoracic pressure and improve venous return to the heart. The valve is a part of a mask or other breathing device such as an endotracheal tube, and may open at high or low pressures (called "cracking pressures") == Overview == ITDs are still in the early phases of clinical use, but preliminary investigational studies have suggested a potential benefit in achieving return of spontaneous circulation (ROSC) and early improvement after cardiopulmonary arrest in humans.

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