Sunday, September 4, 2011

Automatic Setting of T-Low during Airway Pressure Release Ventilation: Is it Beneficial?

Setting T-Low during APRV (a.k.a. Bi-Level, Bi-Vent) can be confusing and time consuming, to make it even more complicated there are three published techniques on how to set T-Low [1].

One method is setting T-Low based on the measured peak expiratory flow rate [2, 3]. The new Draeger Evita Infinity V500 ventilator allows the operator to set an “Auto-release” based on zero (0)-to- 80% of the Peak expiratory flow. This feature is nice since the operator does not have to continually assess the waveform &titrate the T-Low setting.

Conversely, this may be the least effective way to set T-Low in regards to lung protective goals, due to the inconsistent exhaled tidal volumes & auto-PEEP created with this technique [4].


[2]. Richey, S. (2009). Optimal T-Low Settings.

[3]. Richey, S. (2010). A Quick & Easy Way to Set T-Low During Airway Pressure Ventilation.

[4]. Richey, S. (2011). Setting T-Low During Airway Pressure Release Ventilation to Achieve Lung Protective Goals.