Medical ventilators often include humidifiers for increased patient comfort. This led to him developing efficient respirators and ventilators. Patients requiring ventilators were kept alive with hand-powered resuscitation bags. Most attic ventilators fitted to homes are powered off mains electricity. These oasts had louvred ventilators instead of a cowl. "Carpathia"s lower decks were well-ventilated by means of deck ventilators, supplemented by electric fans. Portable ventilators may be required to support breathing. Complex technology and equipment is often in use, particularly mechanical ventilators and patient monitoring systems. It is rigid cylindrical in shape with air and water proof zippers and ventilators. Most modern ventilators have basic monitoring tools. The machines could also be used to pump water or power ventilators in mines. Adjusting to the realities of ventilators, feeding tubes, bedsores, and muscle wasting may be difficult. Doctors can stop giving a patient life sustaining treatments such as ventilators, feeding tube etc. Positive pressure ventilators reduced mortality in bulbar patients from 90% to 20%. APRV is used by many brands and models of mechanical ventilators under different names.