  We present a viable prototype of a simple mechanical ventilator intended as a
last resort to ventilate COVID-19 patients. The prototype implements the
pressure-controlled continuous mandatory ventilation mode (PC-CMV) with
settable breathing rates, inspiration/expiration time ratios and FiO2
modulation. Although safe, the design aims to minimize the use of technical
components and those used are common in industry, so its construction may be
possible in times of logistical shortage or disruption or in areas with reduced
access to technical materials and at a moderate cost, affordable to lower
income countries. Most of the device can be manufactured by modest technical
means and construction plans are provided.
