Table of Contents
Why does paradoxical aciduria occur?
Paradoxic aciduria can be a feature of a primary metabolic alkalosis due to vomiting or sequestration of hydrochloric acid-rich gastric contents in all species, but particularly ruminants.
Why is urine acidic in pyloric stenosis?
INFANTS WITH PYLORIC STENOSIS The excess loss of Cl depletes extracellular chloride and with the luminal loss of Hydrogen ions produces a metabolic alkalosis. The kidney tries to initially maintain blood pH by excreting an alkaline urine.
Why is bicarbonate elevated in pyloric stenosis?
This pathophysiology is understood, considering that emesis results in hydrogen and chloride ion losses. The pancreas will secrete bicarbonate when stimulated by hydrogen reaching the duodenum but without this stimulus, there results an increase in serum bicarbonate and subsequent alkalosis.
What is the electrolyte imbalance in pyloric stenosis?
The classic electrolyte imbalance of pyloric stenosis is hypochloremic, hypokalemic metabolic alkalosis. The diagnosis of pyloric stenosis is being made earlier because of earlier use of sonography so that those laboratory abnormalities are now present in less than 50% of cases.
Why does pyloric stenosis cause hyponatremia?
This prolonged vomiting causes progressive loss of fluids rich in hydrochloric acid, which causes the kidneys to retain hydrogen ions in favor of potassium. The dehydration may result in hypernatremia or hyponatremia and may result in prerenal renal failure.
What is the pathophysiology of pyloric stenosis?
The hallmark of pyloric stenosis is marked hypertrophy and hyperplasia of both the circular and longitudinal muscular layers of the pylorus. [3] This thickening leads to the narrowing of the lumen of the gastric antrum. The pyloric canal becomes lengthened. The muscles of the pylorus become thickened.
What is paradoxical alkaline urine?
This situation arises from the primary loss of gastric acid from repeated vomiting or drainage resulting in loss of chloride and potassium ions, as well as volume. Despite the metabolic alkalosis, the body still produces an acidic urine. The specific situation in this scenario is called “paradoxical aciduria”.
How does pyloric stenosis cause dehydration?
This is caused by stomach muscles trying to force food through the narrowed pylorus. Dehydration. Your baby might cry without tears or become lethargic. You might find yourself changing fewer wet diapers or diapers that aren’t as wet as you expect.
What is Hypochloremic Hypokalemic metabolic alkalosis?
Hypochloremic alkalosis results from either low chloride intake or excessive chloride wasting. Whereas low chloride intake is very uncommon, excessive chloride wasting often occurs in hospitalized children, usually as a result of diuretic therapy or nasogastric tube suctioning.
Why does pyloric stenosis cause non bilious vomiting?
Babies with pyloric stenosis usually have progressively worsening vomiting during their first weeks or months of life. The vomiting is often described as non bilious and projectile vomiting, because it is more forceful than the usual spit ups commonly seen at this age.
Why does bicarbonate increase in metabolic alkalosis?
Metabolic alkalosis involves a primary increase in serum bicarbonate (HCO3-) concentration, due to a loss of H+ from the body or a gain in HCO3-.
What causes projectile vomiting in pyloric stenosis?
Pyloric stenosis is a narrowing of the pylorus―a muscular valve at the bottom of the stomach. When it becomes too think (hypertrophied), breastmilk or formula can’t get through to the small intestines. This leads to excessive, projectile vomiting.
What is the pathophysiology of hypochloremia?
Hypochloremia is usually caused by excess use of loop diuretics, nasogastric suction, or vomiting. Metabolic alkalosis is usually present with hypochloremia. Vomiting causes loss of hydrochloric acid.
Why does pyloric stenosis cause metabolic alkalosis?
Pyloric stenosis usually results in metabolic alkalosis with associated hypochloremia and hypokalemia due to a loss of hydrogen and chloride ions from vomiting gastric contents. However, if the dehydration is severe enough, paradoxical aciduria may occur.