Medical Ventilator

Overview

A critical-care ventilator supports or replaces a patient's breathing by delivering a controlled mixture of oxygen and air to the lungs at set volumes, pressures, and rates. It can take over breathing entirely for a paralyzed or sedated patient or assist a patient's own efforts, synchronizing with them through a range of modes. Precise control of delivered volume and pressure, and continuous monitoring of the result, protect the lungs from injury.

Breath delivery is the job of the Gas Delivery Unit unit. An internal turbine blower pressurizes the breathing gas, an inspiratory flow-control valve shapes each delivered breath, and an expiratory valve with PEEP control holds residual pressure at end-exhalation to keep alveoli open. Oxygen and air are blended to the set FiO2 by the Gas Mixing Module module, fed through the Pneumatic Manifold of regulators and filters.

How it works

Every breath is closed-loop controlled from the Sensor Suite, whose flow and pressure sensors at the airway measure delivered volume and pressure breath by breath, letting the controller hit a volume or pressure target and detect the patient's inspiratory effort to trigger assisted breaths. Gas reaches the patient through the Breathing Circuit, heated and humidified inspiratory and expiratory limbs with a patient-side wye.

Control is split for safety: the Main Control Board runs the breath delivery and modes, while an Independent Monitoring Board independently watches airway pressure and volume and raises alarms or opens to ambient if the primary controller fails. The clinician sets mode, volume, rate, PEEP, and FiO2 on the User Interface Panel, and the Power System runs the ventilator from mains with an internal battery that sustains ventilation through power loss and transport.