A Portable Emergency Ventilator (PEV) is a device that provides ventilation to a person who is incapable of breathing on his or her own. The device’s ability to provide air to a patient’s lungs could potentially save a patient’s life in an emergency situation if the device is working properly. However, the human respiratory system is sensitive and can easily be damaged by such a device. The size and strength of a person’s lung is dependent on the person’s age and health. Therefore, if the device is not correctly calibrated or designed, it could over-inflate the lungs of a patient or allow the lungs to collapse.
In the early 1990’s Jeff Gutterman and Roman Press developed a PEV called the MEDIRESP III. When the MEDIRESP III was designed, its competitors were able to perform under three different modes: constant mandatory ventilation, manual mode, and assist mode. The MEDIRESP III added a CPR mode. Also, unlike its competitors, the MEDIRESP III did not require an oxygen tank but instead provided air from the surrounding environment. Over a decade later, Rochester Institute of Technology multidisciplinary senior design teams 13026 and 13027 were tasked with incorporating modern technology and making it more user friendly. This would make the newer generations of the MEDIRESP lighter, more efficient, and easier to use.
Rochester Institute of Technology multidisciplinary senior design team 14026 was then tasked with building a system to characterize the MEDIRESP. The testing system models the human respiratory system and collects flow and pressure readings. The testing systm is made up of an orifice plate subassembly that is representative of the human trachea. The resistance can be altered by switching which orifice plate is being used. Based on the resistance, flow rate, and pressure measurements that the testing system reads in through LabView the team can determine what type of person the PEV can safely be used on. It is important that the team can characterize these results because the respiratory system changes for person to person based on age, height, and health. If the PEV is used on the wrong type of person the person’s lungs could be over-inflated or collapse.
In addition to characterizing the type of person a PEV can be used on, the testing system also has a subassembly that simulates if the PEV would respond to a person gasping for breath in assist mode. The MEDIRESP is designed to recognize a person’s attempt to inhale. An inhale causes a negative pressure in the system that will trigger the PEV to provide a breath. The testing system uses a syringe and linear actuator to create a measurable inhale. The team can then determine what range of negative pressure the PEV is able to detect. This testing system would be able to be used to characterize any portable emergency ventilator.