Related Experiment Video
Updated: Apr 17, 2026

Veno-Venous Extracorporeal Membrane Oxygenation in a Mouse
Published on: October 24, 2018
The effect of bicarbonate administration via continuous venovenous hemofiltration on acid-base parameters in
Andrew S Allegretti1, Jennifer E Flythe2, Vinod Benda3
1Division of Nephrology, Department of Medicine, Massachusetts General Hospital, 7 Whittier Place, Suite 106, Boston, MA 02114, USA.
Background:
Acute kidney injury (AKI) and metabolic acidosis are common in the intensive care unit. The effect of bicarbonate administration on acid-base parameters is unclear in those receiving continuous venovenous hemofiltration (CVVH) and mechanical ventilatory support.
Methods:
Metabolic and ventilatory parameters were prospectively examined in 19 ventilated subjects for up to 96 hours following CVVH initiation for AKI at an academic tertiary care center. Mixed linear regression modeling was performed to measure changes in pH, partial pressure of carbon dioxide (pCO2), serum bicarbonate, and base excess over time.
Results:
During the 96-hour study period, pCO2 levels remained stable overall (initial pCO2 42.0±14.6 versus end-study pCO2 43.8±16.1 mmHg; P=0.13 for interaction with time), for those with initial pCO2≤40 mmHg (31.3±5.7 versus 35.0±4.8; P=0.06) and for those with initial pCO2>40 mmHg (52.7±12.8 versus 53.4±19.2; P=0.57). pCO2 decreased during the immediate hours following CVVH initiation (42.0±14.6 versus 37.3±12.6 mmHg), though this change was nonsignificant (P=0.052).
Conclusions:
We did not detect a significant increase in pCO2 in response to the administration of bicarbonate via CVVH in a ventilated population. Additional studies of larger populations are needed to confirm this finding.
Related Concept Videos
Bicarbonate-Carbonic Acid Buffer
Respiratory Regulation of Acid-Base Balance
When carbon dioxide levels increase in the blood, more H+ and HCO3⁻ are...
Diagnosing Acidosis and Alkalosis
First, the pH level is assessed to determine whether the blood pH is normal (7.35–7.45), low (acidosis), or high (alkalosis).
Next, the PCO2 and...
Disorders of Acid-Base Balance
Respiratory Acidosis and Alkalosis
Respiratory acidosis occurs due to an increase in the partial pressure of carbon dioxide PCO2 in the blood. It often arises from shallow breathing or impaired gas exchange caused by...
Acid-Base Balance
When the pH of arterial blood rises above 7.45, it results in a condition called alkalosis. Conversely, a drop below 7.35 leads to...
Renal Regulation of Acid-Base Balance
In the kidneys, cells within the proximal convoluted tubules (PCT) and the collecting ducts secrete hydrogen ions (H+) into the tubular fluid. Specifically, in the PCT, Na+/H+ antiporters secrete H+ while reabsorbing Na+.
However, the intercalated cells in...

