1. Field of the Invention
The present invention relates to ventilation systems used to treat respiratory disorders or diseases. Ventilation systems includes invasive and non-invasive ventilation, Continuous Positive Airway Pressure (CPAP), Bilevel therapy and treatment for sleep disordered breathing (SDB) conditions such as Obstructive Sleep Apnea (OSA), and for various other respiratory disorders and diseases. The ventilation system can be used in emergency situations to provide rapid invasive or non-invasive respiratory ventilator assistance, or in general to provide non-invasive ventilator assistance.
2. Description of Related Art
Ventilation of a patient involves the delivery of a breathable gas (typically ambient air to which a complementary gas such as oxygen can be added) pressurised above atmospheric pressure to a patient via a conduit, and a mask or tracheotomy tube. The main aim of mechanical ventilation is to simply assist with breathing.
There are many conditions that require assisted and/or controlled ventilation of the patient. It is common to use ventilator devices for diseases where mechanical ventilation is needed, for example in neuromuscular disease where volume controlled ventilation is required. These devices may also be used for other respiratory diseases or disorders, such as for the continuous positive airway pressure (CPAP) treatment of obstructive sleep apnea.
For either application of assisted and/or controlled ventilation, the pressure of the gas delivered to patients can be constant level, bi-level (in synchronism with patient breathing) or auto-adjusting in level. Further, some troubles require feeding the patient with a controlled volume of breathable gas, such as for neuromuscular patients. Throughout this specification reference to ventilation system is intended to incorporate a reference to any one of, or combinations of, these forms of pressurised gas supply.
Ventilation is commonly used in emergency situations to provide effective respiratory assistance to people in respiratory distress. For example to victims in car accidents, heart attacks, drug overdoses or other distressing situations. Under emergency conditions medical paramedics commonly provide ventilation using manual ventilation devices such as a bag valve mask. A bag valve ventilation technique functions in a similar manner to the well known mouth-to-mouth resuscitation technique except the air being blown into patients lungs comes from the bag rather than an individuals lungs. In contrast a mechanical ventilator uses a machine to blow the air into a patients lung. Mechanical ventilators are rarely used in emergency situations due to their larger size, complexity and time required to set-up such devices.
Ventilation can be provided as invasive ventilation or non-invasive ventilation. Invasive ventilation typically includes the use of a Laryngeal mask; endotracheal tube or intubation or Cricothyroidotomy whilst non-invasive ventilation generally includes the use of a mask or nasal prongs.
During emergency situations it has been proven that the sooner medical treatment is initiated the higher the rate of survival. Many countries now employ a rapid response emergency paramedic, particularly motorcycle paramedics, to provide quicker emergency support than that provided by current ambulance services. A rapid response emergency paramedic commonly operates as a single man unit. Thus, size, weight and time to set-up ventilation are critical to the successful treatment and ultimate survival of the victim.
Mechanical ventilators are predominantly used in hospitals or for long term care as they are generally large and complex. However, there have been some portable mechanical ventilators developed. U.S. Pat. No. 4,651,731 Vicenzi et al. 1987 discloses a portable fully self contained single patient ventilator/resuscitator device that has minimal features and modes of ventilation to reduce the cost and complexity so that minimally trained personnel can operate the device. Another such device is the Smiths Medical—Pneupac VR1, a compact design that is very simple.
U.S. Pat. No. 6,848,444 Smith et al. 2005 discloses a patient ventilator integrated with state-of the-art commercial off the shelf physiologic sensors and a digitally controlled feedback system for automated monitoring and regulation for use by the first responder to provide on-scene critical life-saving support through more advanced levels of care during the critical minutes after an injury and during evacuation.
There still remains a need for smaller, lighter, more portable like support devices that are easy to use and quick to set up so they can be operated in emergency type situations where time is very important.
None of these prior art devices provides an entirely satisfactory solution to the provision of emergency ventilation to the patient, nor to ease of construction and use requirements required under such emergency or rapid response conditions.