Leak management—the ResMed approach
ResMed’s vented therapy solutions offer a range of intelligent leak management technologies. Together these work to minimize, monitor and compensate for leak and maintain patient–ventilator synchrony. This is the key to effective noninvasive ventilation:
- Circuit tests and settings ensure effective therapy with accurate monitoring of leak and patient volumes.
- Interface Selection features help the ventilator respond to mask vent flow; that is intentional leak.
- Vsync technology monitors and compensates for unintentional leak and works with TiControl™ to optimize synchrony.
To estimate patient respiratory flow, ResMed devices start with known values of pressure and total flow measured at the device. Based on these known values, along with knowledge of circuit impedance, mask pressure is deduced. Using the deduced mask pressure and information regarding interface selection, the device determines vent flow (or intentional leak).
ResMed’s leak compensation algorithm, Vsync, estimates unintentional leak based on mask pressure and flow. The ventilator subtracts intentional and unintentional leak from the total flow to estimate the patient respiratory flow. It then uses the patient respiratory flow to trigger and cycle breaths in sync with the patient. Thus ResMed’s advanced leak management technologies contribute directly to comfortable and effective noninvasive positive pressure ventilation.
Circuit impedance compensation
Impedance in the circuit varies based on circuit components, including filters, humidifiers, tubing and other accessories. Unknown circuit impedance can lead to errors in pressure delivered at the mask and inaccurate monitoring, impacting the effective delivery of therapy.
ResMed’s therapy solutions are designed to overcome impedance in various ways, depending on the device. The most common way to evaluate circuit impedance is through the use of the Learn Circuit feature.
Interface selection
ResMed offers an exceptional selection of vented masks designed to ensure adequate washout of carbon dioxide while minimizing leak and maintaining patient comfort. All of these benefits are extremely important for patients utilizing NIV therapy.
Many ResMed devices offer an interface selection menu. Selecting the suitable interface enables the device to factor in the intentional leak emitting from the mask vent, which allows for more accurate unintentional leak reporting and alarm accuracy.