Abstract
The ability to diagnose disease or monitor treatment response using a breath test is an attractive concept. However, despite a variety of analysis techniques, and a growing body of research, there are only a limited number of breath tests used routinely. Many of the available techniques to measure volatile compounds lack the sensitivity or ability to deal with humidity to be of real use for breath testing. Selected Ion Flow Tube- Mass Spectrometry (SIFT-MS) however can quantitate compounds in breath regardless of humidity, and has demonstrated potential for rapid, non-invasive detection of many volatile compounds. This review describes the requirements of a SIFT-MS device including hardware adaptations, adequate sensitivity, precision, and response time, for the monitoring of breath from ambulatory or intubated and ventilated patients. The second part of the development of bedside breath analysis tools is to package the SIFT-MS with appropriate clinical data so that breath volatiles can be used to monitor, inflammation, infection, cancer or metabolic diseases. To this end, challenges and considerations, such as understanding the physiology of the potential volatile marker, and how best to determine the optimal breath test for a particular compounds are described. With the continued developments to the SIFT-MS instrumentation and methodology, and the growing understanding of the associations between breath biomarkers and disease, the potential for routine monitoring of breath volatiles at the bedside may be realized.