Table 1 Specifications for a minimally acceptable ventilator to treat COVID-19 patients with mild or moderate symptoms.
From: Repurposing CPAP machines as stripped-down ventilators
Ventilation variable | Description | Values |
|---|---|---|
Triggering mechanism | A method to initiate the inspiration phase | Time-triggering, flow-triggering |
Cycling mechanism | A method to end the inspiration phase | Time-cycling, flow-cycling |
Breath control variable | A parameter that describes the mechanism to assist the patient’s breathing | Pressure-control (PC) |
Breath sequence | A pattern of mandatory and/or spontaneous breaths | Intermittent mandatory ventilation (IMV) |
Targeting Scheme | A method used by the ventilator to achieve a specific ventilation pattern | Set-point (s) |
Ventilation Mode | A term to describe the set of ventilation operations based on the selected breath control variable, breath sequence and targeting scheme | PC-IMVs,s |
I:E ratio | The ratio of the inspiration (I) and the expiration (E) phase during ventilation | 1:1, 1:2 |
Respiratory rate | The number of breaths per minute (bpm). Here, it is the number of mandatory breaths per minute. The number of spontaneous breaths per minute cannot be lower than the number of mandatory breaths per minute | 8–30 bpm |
Positive end-expiratory pressure (PEEP) | The airway pressure at the end of the exhalation phase | At least 5 cmH2O |
Peak inspiratory pressure | The airway pressure set at the CPAP machine | 15–20 cmH2O |
Maximum airway pressure | The upper-pressure limit in the patient’s airways | 30 cmH2O |
