Improving the prognostic value of ∆PCO2 following cardiac surgery: a prospective pilot study

  • Philippe PortranEmail author
  • Matthias Jacquet-Lagreze
  • Remi Schweizer
  • William Fornier
  • Laurent Chardonnal
  • Matteo Pozzi
  • Marc-Olivier Fischer
  • Jean-Luc Fellahi
Original Research


Conflicting results have been published on prognostic significance of central venous to arterial PCO2 difference (∆PCO2) after cardiac surgery. We compared the prognostic value of ∆PCO2 on intensive care unit (ICU) admission to an original algorithm combining ∆PCO2, ERO2 and lactate to identify different risk profiles. Additionally, we described the evolution of ∆PCO2 and its correlations with ERO2 and lactate during the first postoperative day (POD1). In this monocentre, prospective, and pilot study, 25 patients undergoing conventional cardiac surgery were included. Central venous and arterial blood gases were collected on ICU admission and at 6, 12 and 24 h postoperatively. High ∆PCO2 (≥ 6 mmHg) on ICU admission was found to be very frequent (64% of patients). Correlations between ∆PCO2 and ERO2 or lactate for POD1 values and variations were weak or non-existent. On ICU admission, a high ∆PCO2 did not predict a prolonged ICU length of stay (LOS). Conversely, a significant increase in both ICU and hospital LOS was observed in high-risk patients identified by the algorithm: 3.5 (3.0–6.3) days versus 7.0 (6.0–8.0) days (p = 0.01) and 12.0 (8.0–15.0) versus 8.0 (8.0–9.0) days (p < 0.01), respectively. An algorithm incorporating ICU admission values of ∆PCO2, ERO2 and lactate defined a high-risk profile that predicted prolonged ICU and hospital stays better than ∆PCO2 alone.


Cardiac surgery Central venous- arterial pCO2 difference Tissue perfusion Lactic acid Oxygen extraction ratio 



The proofreading of this article was supported by the Bibliothèque Scientifique de l’Internat de Lyon and the Hospices Civils de Lyon.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Informed consent

According to the French law and because data were collected during routine care, authorization was granted to waive written informed consent. However, verbal consent was obtained from all study participants before surgery.


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Copyright information

© Springer Nature B.V. 2019

Authors and Affiliations

  1. 1.Service d’Anesthésie RéanimationHôpital Cardiovasculaire et Pneumologique Louis Pradel, Hospices Civils de LyonLyon Cedex 03France
  2. 2.Département de Chirurgie cardiaque, Hôpital Cardiovasculaire et Pneumologique Louis Pradel, Hospices Civils de LyonLyon Cedex 03France
  3. 3.Service d’Anesthésie RéanimationCHU de Caen, Avenue de la Côte de NacreCaenFrance
  4. 4.Institut Hospitalo-Universitaire Cardioprotection, INSERM U1060, Université Claude Bernard Lyon 1LyonFrance

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