Related Experiment Video
Updated: Jan 6, 2026

Point-of-Care Ultrasound for Peripheral Veno-Arterial Extracorporeal Membrane Oxygenation Without Left Ventricular Venting
Published on: January 17, 2025
Carbon dioxide elimination as a guide to venoarterial extracorporeal membrane oxygenation weaning: a prospective
Yazhu Yang1, Liangshan Wang1, Chenglong Li1
1Center for Cardiac Intensive Care, Beijing Anzhen Hospital, Capital Medical University, Beijing, People's Republic of China.
Background:
Despite the increasing use of venoarterial extracorporeal membrane oxygenation (VA-ECMO) in cardiogenic shock (CS), reliable predictors of successful weaning remain poorly defined. This study investigated the role of carbon dioxide elimination parameters in VA-ECMO weaning.
Methods And Results:
To assess the potential role of end-tidal carbon dioxide (EtCO2) in predicting successful VA-ECMO weaning, we conducted a prospective observational study at Anzhen Hospital between January 2023 and December 2024. The primary endpoint was the predictive performance of EtCO2 and VCO2NL ratio for successful VA-ECMO weaning. Real-time EtCO2 monitoring was performed using infrared capnography in mechanically ventilated patients, and the ratio of native lung carbon dioxide elimination (VCO2NL) to total carbon dioxide elimination (VCO2TOT) was calculated as the VCO2NL ratio. Dynamic changes in these parameters were analysed in relation to weaning outcomes. Among 294 patients receiving VA-ECMO for refractory CS during the study period, 91 were included, yielding 562 data points. Both EtCO2 (odds ratio [OR] = 1.26, 95% confidence interval [CI] 1.17-1.37, p < 0.0001) and the VCO2NL ratio (1.14, 95% CI 1.09-1.21, p < 0.0001) showed significant correlations with successful weaning. A VCO2NL ratio > 79% and EtCO2 > 34 mmHg showed strong predictive value for successful weaning (area under the receiver operating characteristics (ROC) curve values of 0.85 [95% CI 0.80-0.89] and 0.84 [95% CI 0.79-0.89], p < 0.0001).
Conclusions:
EtCO2 and the VCO2NL ratio may be valuable indicators for predicting successful VA-ECMO weaning. Higher EtCO2 and VCO2NL ratio values are associated with a greater likelihood of successful weaning.
Related Concept Videos
Assessment of Diffusion and Perfusion
The Role of Diffusion in Respiration
Diffusion is the process by which molecules move from an area of higher concentration to an area of lower concentration. In the respiratory system, this...
Mechanical Ventilation III: Noninvasive Ventilation
Noninvasive Positive-Pressure Ventilation...
Mechanical Ventilation II: Invasive Ventilation
Negative-Pressure Ventilators
Negative-pressure ventilators create a vacuum around the chest or body to draw air into the lungs, simulating breathing. This method does not require an...
Carbon Dioxide Transport in the Blood
Forms of CO2 Transport
1. Dissolved in plasma: A small percentage (7-10%) of CO2 is transported and dissolved directly in the plasma.
2. Carbaminohemoglobin: Just over 20% of CO2 is chemically bound to...
Respiratory Regulation of Acid-Base Balance
When carbon dioxide levels increase in the blood, more H+ and HCO3⁻ are...
Oxygen Delivering System II: Venturi Mask and Transtracheal Oxygen
Venturi Mask
The Venturi mask, named after the Venturi effect, is designed to deliver precise oxygen concentrations. It consists of a large tube with an oxygen inlet that narrows down, causing a pressure drop that pulls air in through adjustable side ports. The mask is a lightweight,...

