Lactate Arterial-Central Venous Gradient among COVID-19 Patients in ICU: A Potential Tool in the Clinical Practice

Giuseppe Nardi; Gianfranco Sanson; Lucia Tassinari; Giovanna Guiotto; Antonella Potalivo; Jonathan Montomoli; Fernando Schiraldi

doi:10.1155/2020/4743904

Lactate Arterial-Central Venous Gradient among COVID-19 Patients in ICU: A Potential Tool in the Clinical Practice

Crit Care Res Pract. 2020 Sep 25:2020:4743904. doi: 10.1155/2020/4743904. eCollection 2020.

Authors

Giuseppe Nardi¹, Gianfranco Sanson², Lucia Tassinari¹, Giovanna Guiotto³, Antonella Potalivo¹, Jonathan Montomoli¹, Fernando Schiraldi⁴

Affiliations

¹ Dept. of Anaesthesia and Intensive Care, Infermi Hospital, Viale Settembrini 2, 47921 Rimini, Italy.
² Clinical Dept. of Medical, Surgical and Health Sciences, University of Trieste, Strada Di Fiume 447, 34149 Trieste, Italy.
³ Dept of Emergency Medicine, AORN San Pio, Via Pacevecchia 53, 82100 Benevento, Italy.
⁴ Emergency Dept San Paolo Hospital, Via Terracina, 80125 Naples, Italy.

Abstract

Objective: In physiological conditions, arterial blood lactate concentration is equal to or lower than central venous blood lactate concentration. A reversal in this rate (i.e., higher lactate concentration in central venous blood), which could reflect a derangement in the mitochondrial metabolism of lung cells induced by inflammation, has been previously reported in patients with ARDS but has been never explored in COVID-19 patients. The aim of this study was to explore if the COVID-19-induced lung cell damage was mirrored by an arterial lactatemia higher than the central venous one; then if the administration of anti-inflammatory therapy (i.e., canakinumab 300 mg subcutaneous) could normalize such abnormal lactate a-cv difference.

Methods: A prospective cohort study was conducted, started on March 25, 2020, for a duration of 10 days, enrolling 21 patients affected by severe COVID-19 pneumonia undergoing mechanical ventilation consecutively admitted to the ICU of the Rimini Hospital, Italy. Arterial and central venous blood samples were contemporarily collected to calculate the difference between arterial and central venous lactate (Delta a-cv lactate) concentrations within 24 h from tracheal intubation (T ₀) and 24 hours after canakinumab administration (T ₁).

Results: At T ₀, 19 of 21 (90.5%) patients showed a pathologic Delta a-cv lactate (median 0.15 mmol/L; IQR 0.07-0.25). In the 13 patients undergoing canakinumab administration, at T ₁, Delta a-cv lactate decreased in 92.3% of cases, the decrease being statistically significant (T ₀: median 0.24, IQR 0.09-0.31 mmol/L; T ₁: median -0.01, IQR -0.08-0.04 mmol/L; p=0.002).

Conclusion: A reversed Delta a-cv lactate might be interpreted as one of the effects of COVID-19-related cytokine storm, which could reflect a derangement in the mitochondrial metabolism of lung cells induced by severe inflammation or other uncoupling mediators. In addition, Delta a-cv lactate decrease might also reflect the anti-inflammatory activity of canakinumab. Our preliminary findings need to be confirmed by larger outcome studies.