Related Experiment Video
Updated: Aug 19, 2026

Determination of the Gas-phase Acidities of Oligopeptides
Published on: June 24, 2013
Determinants of plasma acid-base balance
1The CRISMA Laboratory, Department of Critical Care Medicine, University of Pittsburgh School of Medicine, 608 Scaife Hall, Pittsburgh, PA 15213-2582, USA. kellumja@ccm.upmc.edu
Abstract:
An advanced understanding of acid-base physiology is central to the practice of critical care medicine. Intensivists spend much of their time managing problems that are related to fluids, electrolytes, and blood pH. Recent advances in the understanding of acid-base physiology occurred as the result of the application of basic physical-chemical principles of aqueous solutions to blood plasma. This analysis revealed three independent variables that regulate pH in blood plasma: carbon dioxide, relative electrolyte concentrations, and total weak acid concentrations. All changes in blood pH, in health and in disease, occur through changes in these three variables. This article reviews the physical-chemical approach to acid-base balance and considers clinical implications for these findings.
Related Concept Videos
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...
Respiratory Regulation of Acid-Base Balance
When carbon dioxide levels increase in the blood, more H+ and HCO3⁻ are produced, leading to a...
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...
pH Homeostasis
Respiratory Regulation of...
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 HCO3− values are examined to...
