Two researchers from the University of Buffalo have developed a new ventilator system, specifically designed for ICU care, that, by using inhalational anesthetic agents, can avoid some of the dosing issues that anesthesiologists have to deal with when sedating patients in “The Unit.” Additionally, the device may be capable of safely supporting a number of patients on the same machine, according to the University of Buffalo press release.
We contacted Medical Conservation Devices (MCD) of Buffalo, the firm working on implementing this technology, to get more information about the system. According to the documents we have received from the company, the ventilator seems to be a carefully designed closed-circuit anesthesia system, capable of delivering “balanced sedation” to ICU patients by using inhaled anesthetics as “the primary sedation and pain control regimen.”
More about the device, from the MCD’s white paper:
Medical Conservation Devices product leverages a well known concept in the medical device field known as ‘a-bag-in-a-box’ and is made up to a disposable rebreathing system (named the Universal Isolator) and non-disposable controller. This approach allows a cheaper solution to anesthetic delivery by only providing those incremental functions by leveraging the existing installed base of equipment and monitoring in the ICU. The innovative element of the MCD Universal Isolator is its ability to self-regulate oxygen and fresh gas flow in order to deal with the unique patient situation in the ICU. In anesthetic mode, this fresh gas flow would also include the amount of anesthetic gas (measured as a percentage of gas flow) to the patient.
An image of the first generation device is shown above. Future generations will incorporate all system elements in a single free standing console.
It is this automation that allows inhaled anesthetic to be practically delivered without an increase in staffing requirements. Staffing requirements are important because unlike surgery, a patient’s ICU stay is typically measured over days, if not weeks. Requiring manual adjustments of gas flow rates every time the patient develops a leak around the endotracheal tube or the critical care nurse suctions the patients would be very expensive.
Furthermore, the device works on any ventilator (even transport vents) and is clinically transparent to the ventilator. The respiratory therapist still dials in the same settings and can be assured the same alarming systems work on the ventilator with or without the MCD Universal Isolator between the patient and the ventilator.
There are several advantages for this approach. First, limited training is required. Second, when the clinician prescribed a set concentration of anesthetic on the non-disposable element, that exact percent of anesthetic is delivered to the patient. This is the traditional way of thinking of anesthetic delivery, rather than having to convert a certain infusion rate from the syringe with the competing solutions and waiting an hour until one can achieve the correct level via trial and error. This feature also provides quicker and easier titration or adjustments during continual use as the patient condition changes.
Finally, the device provides complete isolation between the patient and the environment (ventilator, ICU room, etc.) due to the use of a bag or membrane separating the patient side from the ventilator side, in addition to the series of one-way valves for fresh gas and active scavenging. This allows operating rooms and ICUs to continue to operate without worry of cross contamination during an epidemic, or contagious or immunosupressed patients as we saw in Toronto, Canada during the SARS outbreak. A second generation of the device also allows up to 8 adult patients to share a single ventilator during patient surge scenarios such as mass casualty and pandemics. This is accomplished while providing individualized respiratory settings to each patient (oxygen concentration (FiO2), tidal volume and minute ventilation, and positive end expiratory pressure (PEEP), without cross contamination.
University of Buffalo press release: UB-Designed Ventilator Can Safely Sedate ICU Patients for Less …