Abstract
INTRODUCTION: Mitochondrial dysfunction leading to impairment of oxygen extraction, referred to as cytopathic hypoxia, contributes to morbidity in sepsis. Oxygen consumption (VO2) may be a useful measure of the severity of cytopathic hypoxia. We monitored VO2 and carbon dioxide production (VCO2) in septic patients and investigated the association with hospital survival.
METHODS: We retrospectively identified adult (≥18 years) septic patients from a larger prospective observational cohort of critically ill patients on mechanical ventilation. A gas-exchange monitor recorded continuous VO2 and VCO2 for up to 48 hours. We then tested the association of median VO2, VCO2, respiratory quotient (RQ) and the VO2: lactate ratio with survival.
RESULTS: A total of 46 septic patients were included in the analysis, of whom 28 (61%) survived. Overall median VO2 was not associated with survival (3.72 mL/kg/min [IQR: 3.39, 4.92] in survivors and 3.42 mL/kg/min [IQR: 2.97, 5.26] in non-survivors, p = 0.12). The overall median VCO2 and RQ were also not associated with survival. Adjusting for age and the presence of shock did not change these results. The VO2: lactate ratio was associated with survival (adjusted OR 2.17 [95% CI 1.12, 4.22] per unit increase in ratio, p = 0.03). The percent change in median VCO2 was 11.6% [IQR: -8.2, 28.7] in survivors compared to -8.3% [IQR: -18.0, 4.7] in non-survivors (p = 0.03). The percent changes in median VO2 and RQ were not different between groups.
CONCLUSION: The VO2: lactate ratio was significantly higher in survivors, while there was no association between median VO2 alone and survival. There was a significant difference in change in VCO2 over time between survivors and non-survivors.
Original language | English |
---|---|
Journal | Shock |
Volume | 55 |
Issue number | 6 |
Pages (from-to) | 775–781 |
Number of pages | 7 |
ISSN | 1073-2322 |
DOIs | |
Publication status | Published - Jun 2021 |