Which acid-base imbalance is commonly associated with NG suction and vomiting?

Metabolic alkalosis is commonly associated with NG suction and vomiting due to the loss of gastric acid. When a patient vomits or undergoes gastric suctioning, hydrochloric acid (HCl) is expelled from the stomach. This loss of acid results in a decrease in hydrogen ion concentration in the serum, leading to an increase in the arterial blood pH, which is characteristic of metabolic alkalosis.

Additionally, the loss of potassium and chloride from the gastric contents can contribute to the alkalosis observed in these situations. The body's compensatory mechanisms may attempt to restore normal acid-base balance, but ongoing losses through vomiting or suction can perpetuate the metabolic alkalosis.

Understanding the physiology behind this helps clarify why metabolic alkalosis is the predominant acid-base disturbance seen in patients with significant gastric loss, such as from NG suction or vomiting.