A Mechanical Intermittent Abdominal Pressure Ventilator

Pneumatically driven intermittent abdominal pressure ventilators were a popular means of daytime ventilatory support until the late 1960s paradigm shift to invasive (tracheostomy) mechanical ventilation. However, although many patients still use intermittent abdominal pressure ventilators, currently available turbine-driven portable home care ventilators are not powerful enough to always successfully operate them. We describe a new mechanically driven intermittent abdominal pressure ventilator operated by a 1-pound motor that provided a depth of abdominal compression of almost 2 in in 1.05 to 1.13 secs to normalize alveolar ventilation for a 72-yr-old postpolio survivor. It increased her autonomous 200- to 320-ml tidal volumes by greater than 300 ml to normalize her respiratory rate, relieve her dyspnea, and maintain normal oxyhemoglobin saturation levels throughout daytime hours for a 9-mo period of continuous ventilatory support.