Monitoring nutrition in critically-ill patients
PI: Grant Ritchie
When long term patients are in an Intenstive Care Unit (ICU) and are being helped to breathe mechanically through ventilation, assessing their nutritional needs becomes imperative. Ideally this should be done by a non-invasive measure of whether or not they are using ingested nutrients or deleteriously converting body mass into energy, and Dr Ritchie’s group proposes to do this by measuring the fraction of acetone in their breath. It is known that acetone levels increase when body fat (rather than ingested carbohydrate) is used as metabolic fuel, and the group has a portable instrument which can measure the appropriate levels of acetone in samples provided by a sentient patient. The proposal is to modify this instrument so that it can be incorporated into an ICU ventilation machine, and to partner with a leading medical company (already identified) which is providing an increasing fraction of such machines worldwide, currently at 20% of the market. The new method will be compared with the recommended (but rarely used) indicator of metabolic activity, namely the measurement of oxygen consumption and carbon dioxide production, which Prof Ritchie’s group can now do with unprecedented precision using its (patented) Molecular Flow Sensor: the acetone analyser will be far simpler and less expensive to construct.
On successful completion of the tasks at the end of this project the instrument will be tested on ventilated ICU patients.