Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Meta-Analysis
. 2020 Dec;48(12):1855-1861.
doi: 10.1097/CCM.0000000000004578.

The Use of Central Venous to Arterial Carbon Dioxide Tension Gap for Outcome Prediction in Critically Ill Patients: A Systematic Review and Meta-Analysis

Affiliations
Meta-Analysis

The Use of Central Venous to Arterial Carbon Dioxide Tension Gap for Outcome Prediction in Critically Ill Patients: A Systematic Review and Meta-Analysis

Zainab Al Duhailib et al. Crit Care Med. 2020 Dec.

Abstract

Objectives: In this systematic review and meta-analysis, we assessed whether a high CO2 gap predicts mortality in adult critically ill patients with circulatory shock.

Data sources: A systematic search of MEDLINE and EMBASE electronic databases from inception to October 2019.

Study selection: Studies from adult (age ≥ 18 yr) ICU patients with shock reporting CO2 gap and outcomes of interest. Case reports and conference abstracts were excluded.

Data extraction: Data extraction and study quality assessment were performed independently in duplicate.

Data synthesis: We used the Newcastle-Ottawa Scale to assess methodological study quality. Effect sizes were pooled using a random-effects model. The primary outcome was mortality (28 d and hospital). Secondary outcomes were ICU length of stay, hospital length of stay, duration of mechanical ventilation, use of renal replacement therapy, use of vasopressors and inotropes, and association with cardiac index, lactate, and central venous oxygen saturation.

Conclusions: We included 21 studies (n = 2,155 patients) from medical (n = 925), cardiovascular (n = 685), surgical (n = 483), and mixed (n = 62) ICUs. A high CO2 gap was associated with increased mortality (odds ratio, 2.22; 95% CI, 1.30-3.82; p = 0.004) in patients with shock, but only those from medical and surgical ICUs. A high CO2 gap was associated with higher lactate levels (mean difference 0.44 mmol/L; 95% CI, 0.20-0.68 mmol/L; p = 0.0004), lower cardiac index (mean difference, -0.76 L/min/m; 95% CI, -1.04 to -0.49 L/min/m; p = 0.00001), and central venous oxygen saturation (mean difference, -5.07; 95% CI, -7.78 to -2.37; p = 0.0002). A high CO2 gap was not associated with longer ICU or hospital length of stays, requirement for renal replacement therapy, longer duration of mechanical ventilation, or higher vasopressors and inotropes use. Future studies should evaluate whether resuscitation aimed at closing the CO2 gap improves mortality in shock.

PubMed Disclaimer

Comment in

References

    1. Sakr Y, Reinhart K, Vincent JL, et al.: Does dopamine administration in shock influence outcome? Results of the Sepsis Occurrence in Acutely Ill Patients (SOAP) study. Crit Care Med. 2006;34:589–597.
    1. Gustot T: Multiple organ failure in sepsis: Prognosis and role of systemic inflammatory response. Curr Opin Crit Care. 2011;17:153–159.
    1. Ruokonen E, Takala J, Kari A, et al.: Septic shock and multiple organ failure. Crit Care Med. 1991;19:1146–1151.
    1. Yealy DM, Kellum JA, Huang DT, et al.; ProCESS Investigators: A randomized trial of protocol-based care for early septic shock. N Engl J Med. 2014;370:1683–1693.
    1. Andersen LW, Mackenhauer J, Roberts JC, et al.: Etiology and therapeutic approach to elevated lactate levels. Mayo Clin Proc. 2013;88:1127–1140.

Publication types

LinkOut - more resources