A new ventilator designed to meet the present-day needs of mechanical aid to ventilation in the treatment of respiratory failure

Abstract

A description is presented of an internal ventilator which has the following features: (1) patient-triggering with guaranteed minimum frequency; (2) constant volume or constant ventilation as determined by the physician; (3) continuous, automatic monitoring of expired air tidal volume; (4) optional negative phase when ventilation is maintained at constant levels; (5) control over inspiratory flow rate and air-oxygen ratios. The ventilator has been tested under laboratory conditions and in separate series of short-term and long-term applications, and has been found useful because it provides the responsiveness and flexibility of patient-triggered apparatus, the basic security of constant ventilation or guaranteed minimum ventilation, and an automated system for monitoring ventilation. The rationale for design of a ventilator with these refinements is discussed and relates to the present population of patients requiring mechanical aid to ventilation. © 1965 Canadian Anesthesiologists.