Changes in Exhaled 13CO2/12CO2 Breath Delta Value as an Early Indicator of Infection in ICU Patients

Inclusion Criteria

• age 18 years or older
• critically ill patient admitted to trauma or surgical ICU
• expected duration of hospital stay at least 120 hours (five days) from time of study enrollment
• subject/LAR speaks a language of which the IRB has approved a consent form

Exclusion Criteria

• known infection at the time of enrollment per infection definitions in section 6.2
• known use of systemic antibiotic, antimicrobial and/or antifungal therapy within the last 7 days (See Antibiotic Use section below)
• prolonged antibiotic or antimicrobial use during the perioperative period (See Antibiotic Use section below)
• currently active cancer, or receiving treatment for cancer (including but not limited to: radiation, chemotherapy, systemic orals, etc)
• receiving high frequency ventilatory support
• if not intubated, unable to cooperate with providing a breath sample
• expected death within 24 hours of enrollment or lack of commitment to aggressive treatment by family/medical team (e.g., likely to withdraw life support measures within 24 hrs of screening)
• female who is pregnant or lactating (negative serum or urine pregnancy test results within 48 hours of enrollment or to be performed during screening)
• prisoner
• known participation in an interventional research study within 30 days prior to enrollment (note: to be eligible, any interventional treatment must have ended at least 30 days ago)
• Individuals who are directly affiliated with sponsor or study staff, or their immediate families. Immediate family is defined as spouse, domestic partner, parent, child, or sibling whether legally adopted or biological.
• Any patient that is deemed unfit for study participation, per the Investigator's discretion.