Monitoring Transcutaneously Measured Partial Pressure of CO 2 During Intubation in Critically Ill Subjects

• Published in: Respiratory care Vol. 66; no. 6; p. 1004
• Main Authors: Frérou, Aurélien, Maamar, Adel, Rafi, Sonia, Lhommet, Claire, Phelouzat, Pierre, Pontis, Emmanuel, Reizine, Florian, Lesouhaitier, Mathieu, Camus, Christophe, Le Tulzo, Yves, Tadié, Jean-Marc, Gacouin, Arnaud
• Format: Journal Article
• Language: English
• Published: United States 01.06.2021
• Subjects: Carbon Dioxide; Critical Illness; Humans; Intubation, Intratracheal - adverse effects; Noninvasive Ventilation; Oxygen; Partial Pressure; Prospective Studies; hypotension; intubation; intensive care unit; mechanical ventilation; preoxygenation; transcutaneous blood gas monitoring
• ISSN: 1943-3654
• DOI: 10.4187/respcare.08009

The risk for severe hypoxemia during endotracheal intubation is a major concern in the ICU, but little attention has been paid to CO variability. The objective of this study was to assess transcutaneously measured partial pressure of CO ([Formula: see text]) throughout intubation in subjects in the ICU who received standard oxygen therapy, high-flow nasal cannula oxygen therapy, or noninvasive ventilation for preoxygenation. We hypothesized that the 3 methods differ in terms of ventilation and CO removal. In this single-center, prospective, observational study, we recorded [Formula: see text] from preoxygenation to 3 h after the initiation of mechanical ventilation among subjects requiring endotracheal intubation. Subjects were sorted into 3 groups according to the preoxygenation method. We then assessed the link between [Formula: see text] variability and the development of postintubation hypotension. A total of 202 subjects were included in the study. The [Formula: see text] values recorded at endotracheal intubation, at the initiation of mechanical ventilation, and after 30 min and 1 h of mechanical ventilation were significantly higher than those recorded during preoxygenation ( < .05). [Formula: see text] variability differed significantly according to the preoxygenation method ( < .001, linear mixed model). A decrease in [Formula: see text] by > 5 mm Hg within 30 min after the start of mechanical ventilation was independently associated with postintubation hypotension (odds ratio = 2.14 [95% CI 1.03-4.44], = .039) after adjustments for age, Simplified Acute Physiology Score II, COPD, cardiac comorbidity, the use of propofol for anesthetic induction, and minute ventilation at the start of mechanical ventilation. [Formula: see text] variability during intubation is significant and differs with the method of preoxygenation. A decrease in [Formula: see text] after the beginning of mechanical ventilation was associated with postintubation hypotension. (ClinicalTrials.gov registration NCT0388430.).