Critical Care |

End-Tidal Carbon Dioxide (EtCO2) as a Surrogate for PaCO2 During Spontaneous Breathing Trial FREE TO VIEW

Deepa Bhanot, MD; Steven Simpson; stites mindy; Heath Latham; Akiko Kubu
Author and Funding Information

KU School of Medicine, Kansas City, Mission, KS

Chest. 2015;148(4_MeetingAbstracts):302A. doi:10.1378/chest.2279773
Text Size: A A A
Published online


SESSION TITLE: Mechanical Ventilation and Respiratory Failure Posters

SESSION TYPE: Original Investigation Poster

PRESENTED ON: Wednesday, October 28, 2015 at 01:30 PM - 02:30 PM

PURPOSE: The use of capnography is expanding from operating rooms and procedural areas to emergency rooms and intensive care units. EtCO2 has been suggested as a non-invasive surrogate for the estimation of PaCO2 in mechanically ventilated adults. The aim of this study was to evaluate the relationship of PaCO2 and EtCO2 in mechanically ventilated patients during spontaneous breathing trials. Our secondary aim was to evaluate the ability of EtCO2 to predict the outcome of the spontaneous breathing trial

METHODS: We performed a prospective, observational study in adult patients receiving mechanical ventilation in a medical intensive care unit. We collected demographic information including age, gender, BMI, primary admission diagnosis, cause of respiratory failure, history of baseline hypercarbia or obstructive lung disease, or pregnancy. EtCO2, PaCO2, tidal volume, respiratory rate, heart rate, blood pressure were collected before and during the trial. We also collected Rapid Shallow Breathing Index, Negative Inspiratory Force, trial outcome (pass/fail), reason for failure of trial. We calculated the PaCO2-EtCO2 gradient before and during the trial and compared the measures using a paired t-test. We then divided patient into 2 groups based on the results of breathing trial and compared gradients before and during the trial using Fisher’s exact test.

RESULTS: There was no difference in the EtCO2-PaCO2 gradient before and during the trial (p=0.1738, 95% CI 4.111- 0.8176). In this small trial we found no differences among gradients before and during weaning, whether patients passed (p 0.3429) or failed (p 0.4472) the weaning trial.

CONCLUSIONS: The consistent relationship of EtCO2 to PaCO2 during spontaneous ventilator trials suggests that the values can be used interchangeably for decision making during weaning.

CLINICAL IMPLICATIONS: The results of this study will result in less arterial blood draws in mechanically ventilated patients.

DISCLOSURE: The following authors have nothing to disclose: Deepa Bhanot, Steven Simpson, stites mindy, Heath Latham, Akiko kubo

No Product/Research Disclosure Information




Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging & repositioning the boxes below.

Find Similar Articles
CHEST Journal Articles
  • CHEST Journal
    Print ISSN: 0012-3692
    Online ISSN: 1931-3543