Troubleshooting Severe Airflow Obstruction With a Pressure-Limited Transport Ventilator: Lessons From Two Cases

Presentations of status asthmaticus or severe chronic obstructive pulmonary disease exacerbation can present a formidable challenge to effective invasive ventilation. The optimal ventilation strategy targets low respiratory rates and high inspiratory flow rates to prolong the expiratory time and minimize dynamic hyperinflation. Although the resulting high peak pressures can usually be accommodated by ICU ventilators, some ventilators have a relatively limited peak pressure capacity as determined by the turbine. Here, we describe two cases of severe airflow obstruction where the desired ventilation strategy required a peak pressure over the capacity of the Hamilton T1 transport ventilator. Changing to a pressure regulated strategy, maximizing the driving pressure, and titrating the inspiratory time overcame the limitation. But, this strategy comes at a cost. Clinicians should be made aware of the possibility of a pressure limitation in their ventilator and understand how to adjust their ventilation strategy appropriately during transitions.