pituitrin and Hyperkalemia

Osmotic demyelination of the brain (ODS) is a dreaded complication that typically occurs several days after aggressive therapy for chronic hyponatraemia, but is eminently avoidable. In this teaching exercise, Professor McCance, an imaginary consultant, is asked to explain how he would have treated a 28-year-old female who had hyperkalaemia, hypoglycaemia, hypotension and hyponatraemia (118 mM) to prevent the development of ODS. He begins with a review of the physiology, including his own landmark work on chronic hyponatraemia associated with a contracted extracellular fluid volume. Adding quantitative analysis, the cause of the excessive rise in plasma sodium concentration is revealed, and a better plan for therapy is proposed.

Topics: Addison Disease; Adult; Brain Diseases; Demyelinating Diseases; Female; Humans; Hyperkalemia; Hypoglycemia; Hyponatremia; Hypotension; Renal Agents; Syndrome; Vasopressins; Water-Electrolyte Imbalance

Topics: Acidosis; Acute Kidney Injury; Alkalosis; Amyloidosis; Hodgkin Disease; Humans; Hyperkalemia; Hypernatremia; Hypertension, Renal; Hypokalemia; Kidney; Kidney Concentrating Ability; Kidney Diseases; Multiple Myeloma; Neoplasms; Nephritis; Nephrotic Syndrome; Osmolar Concentration; Urine; Vasopressins; Water-Electrolyte Balance

Topics: Bloodletting; Carbonic Anhydrase Inhibitors; Chlorides; Diet, Sodium-Restricted; Digitalis Glycosides; Diuresis; Diuretics; Ethacrynic Acid; Furosemide; Heart Failure; Humans; Hyperkalemia; Hypokalemia; Hyponatremia; Kidney Glomerulus; Kidney Tubules; Mineralocorticoid Receptor Antagonists; Organomercury Compounds; Spironolactone; Steroids; Thiazines; Triamterene; Uracil; Vasopressins; Water-Electrolyte Balance; Xanthenes

Topics: Extracellular Space; Humans; Hypercalcemia; Hyperkalemia; Hypernatremia; Hyperparathyroidism; Hypokalemia; Kidney; Magnesium; Vasopressins; Water-Electrolyte Balance

Topics: Accidents, Traffic; Adult; Brain Edema; Brain Injuries; Catecholamines; Fatal Outcome; Glasgow Coma Scale; Hematoma, Subdural; Humans; Hyperglycemia; Hyperkalemia; Hypokalemia; Hypothermia; Insulin; Intracranial Hypertension; Male; Mannitol; Norepinephrine; Potassium; Vasopressins

The effect of haemorrhage on plasma potassium concentration was studied in Sprague-Dawley rats, Brattleboro (BDI) rats and the parent strain Long-Evans (LE) rats. Haemorrhage induced an increase in plasma potassium within 10 min in all rats studied; 20 and 30 min later, plasma potassium was back to prehaemorrhage level. Changes in plasma sodium concentration were not statistically significant. When haemorrhage (1.0% of body weight) was repeated in the same animal preparation, there was a further significant increase in plasma potassium, but a fall in plasma sodium concentration. When vasopressin was injected intravenously, plasma potassium concentration did not change significantly (-0.21 +/- 0.21 mmol/l) in LE rats, whilst it increased significantly (0.69 +/- 0.20 mmol/l, p less than 0.001; paired t-test) in the BDI rats. The results suggest that haemorrhage-induced hyperkalaemia is unrelated to vasopressin, despite the fact that it increases plasma potassium concentration in the BDI rats when injected.

Topics: Animals; Hemodynamics; Hemorrhage; Hyperkalemia; Male; Potassium; Rats; Rats, Brattleboro; Rats, Inbred Strains; Sodium; Species Specificity; Vasopressins

Topics: Acetazolamide; Acid-Base Imbalance; Biological Transport; Diuretics; Drug Resistance; Ethacrynic Acid; Furosemide; Humans; Hydrochlorothiazide; Hyperkalemia; Hypernatremia; Hypokalemia; Hyponatremia; Indapamide; Kidney Tubules, Distal; Kidney Tubules, Proximal; Loop of Henle; Metolazone; Osmolar Concentration; Spironolactone; Triamterene; Vasopressins

Dogs infused with 2 meq KCl/kg per h exhibit electrocardiographic evidence of prelethal cardiotoxicity in about 3 h when serum potassium reaches a level between 10.2-10.5 meq/liter. During this time, their urine output of 30 ml/h is equal to the volume of KCl infused. Studies of the potassium distribution in these animals indicate that 20 percent of the infused ion is added to the extracellular fluid and red blood cell mass, 20 percent is excreted in the urine, while the remaining 60 percent is unaccounted for and presumably transferred to intracellular fluid. Dogs treated with moderately large doses of antidiuretic hormone intramuscularly before and during KCl infusion delay development of prelethal cardiotoxicity for about 5 h, with serum potassium levels comparable to those of untreated dogs. In addition, treated animals display a considerable diuresis and kaluresis with urine volumes nearly 4 times that of the volume infused. The potassium ion distribution in animals given antidiuretic hormone is much different from that of untreated dogs, with 55 percent of the infused ion found in the urine, about 15 percent in extracellular fluid and red blood cell mass, and only 30 percent presumably transferred to intracellular fluid. Transfer of potassium to intracellular fluid was calculated to be 3.1 plus or minus 0.7 meq/kg in antidiuretic-hormone-treated animals and 3.8 plus or minus 0.7 meq/kg in untreated (control) animals. Since these values are, within experimental error, quite comparable, it is possible that antidiuretic-hormone-induced kaluresis and diuresis are involved in protecting some animals from the effects of hyperkalemia by delaying the attainment of cardiotoxic blood levels.

Topics: Animals; Diuresis; Dogs; Erythrocytes; Extracellular Space; Female; Heart; Hyperkalemia; Intracellular Fluid; Kidney; Male; Nephrectomy; Potassium; Time Factors; Vasopressins

Topics: Acid-Base Equilibrium; Acidosis, Respiratory; Chlorides; Diuretics; Electrolytes; Glucose; Humans; Hyperkalemia; Hypokalemia; Hyponatremia; Respiratory Insufficiency; Respiratory Tract Diseases; Vasopressins; Water-Electrolyte Balance

Topics: Adrenal Cortex Hormones; Alkalosis; Blood Urea Nitrogen; Blood Volume; Diuretics; Edema; Ethacrynic Acid; Furosemide; Glomerular Filtration Rate; Humans; Hyperaldosteronism; Hyperkalemia; Hypokalemia; Hyponatremia; Kidney Failure, Chronic; Kidney Tubules; Liver Cirrhosis; Spironolactone; Triamterene; Vasopressins

Topics: Blood Urea Nitrogen; Craniocerebral Trauma; Hematocrit; Humans; Hyperkalemia; Hypernatremia; Hypokalemia; Hyponatremia; Natriuresis; Osmosis; Potassium; Sodium; Vasopressins; Water-Electrolyte Balance

Topics: Aldosterone; Extracellular Space; Humans; Hyperkalemia; Hypernatremia; Hyponatremia; Potassium; Preoperative Care; Sodium; Vasopressins; Water-Electrolyte Balance