Vomiting Effects: Biochemical Abnormality Explained

Repeated vomiting leads to significant loss of gastric fluids. These fluids contain hydrochloric acid ($HCl$), a strong acid.

Mechanism of Alkalosis:

• Loss of $HCl$ from the stomach results in a net loss of hydrogen ions ($H^+$) from the body fluids.
• This loss of acid causes the body's acid-base balance to shift towards alkalinity, increasing the blood pH.
• The kidneys compensate by retaining bicarbonate ($HCO_3^-$) and excreting more acid, further contributing to the alkalotic state. This condition is known as metabolic alkalosis.

Why other options are incorrect:

• Uraemia: Associated with kidney failure and impaired waste product excretion, not directly caused by vomiting.
• Ketosis: Occurs when the body breaks down fat for energy, often seen in starvation or uncontrolled diabetes. While severe vomiting can lead to starvation, ketosis is not the primary immediate consequence.
• Metabolic acidosis: Involves a decrease in blood pH due to acid accumulation or bicarbonate loss, the opposite of what happens when stomach acid is lost via vomiting.

Therefore, the primary biochemical abnormality produced by repeated vomiting is metabolic alkalosis.