These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: End-Tidal-to-Arterial PCO2 Ratio as Signifier for Physiologic Dead-Space Ratio and Oxygenation Dysfunction in Acute Respiratory Distress Syndrome.
    Author: Kallet RH, Lipnick MS.
    Journal: Respir Care; 2021 Feb; 66(2):263-268. PubMed ID: 32636278.
    Abstract:
    BACKGROUND: The ratio of end-tidal CO2 pressure to arterial partial pressure of CO2 ([Formula: see text]) was recently suggested for monitoring pulmonary gas exchange in patients with ARDS associated with COVID-19, yet no evidence was offered supporting that claim. Therefore, we evaluated whether [Formula: see text] might be relevant in assessing ARDS not associated with COVID-19. METHODS: We evaluated the correspondence between [Formula: see text] and the ratio of dead space to tidal volume (VD/VT) measured in 561 subjects with ARDS from a previous study in whom [Formula: see text] data were also available. Subjects also were analyzed according to 4 ranges of [Formula: see text] representing increasing illness severity (≥ 0.80, 0.6-0.79, 0.50-0.59, and < 0.50). Correlation was assessed by either Pearson or Spearman tests, grouped comparisons were assessed using either ANOVA or Kruskal-Wallis tests and dichotomous variables assessed by Fisher Exact tests. Normally distributed data are presented as mean and standard deviation(SD) and non-normal data are presented as median and inter-quartile range (IQR). Overall mortality risk was assessed with multivariate logistic regression. Alpha was set at 0.05. RESULTS: [Formula: see text] correlated strongly with VD/VT (r = -0.87 [95% CI -0.89 to -0.85], P < .001). Decreasing [Formula: see text] was associated with increased VD/VT and hospital mortality between all groups. In the univariate analysis, for every 0.01 decrease in [Formula: see text], mortality risk increased by ∼1% (odds ratio 0.009, 95% CI 0.003-0.029, P < .001) and maintained a strong independent association with mortality risk when adjusted for other variables (odds ratio 0.19, 95% CI 0.04-0.91, P = .039). [Formula: see text] < 0.50 was characterized by very high mean ± SD value for VD/VT (0.82 ± 0.05, P < .001) and high hospital mortality (70%). CONCLUSIONS: Using [Formula: see text] as a surrogate for VD/VT may be a useful and practical measurement for both management and ongoing research into the nature of ARDS.
    [Abstract] [Full Text] [Related] [New Search]