Hyponatremia and Blood Volume Status
40 Questions
4 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What defines hyponatremia in terms of serum/plasma sodium levels?

  • Less than 135 mmol/L (correct)
  • Less than 145 mmol/L
  • Less than 130 mmol/L
  • Less than 120 mmol/L

    • Which condition is primarily associated with increased AVP (ADH) production?

  • Congestive Heart Failure
  • Nephrotic Syndrome
  • SIADH (correct)
  • Cirrhosis

    • What lab result is most commonly implicated in pseudohyponatremia?

  • In vitro hemolysis
  • Hyperlipidemia (correct)
  • Diabetes Insipidus
  • Hyperproteinemia (correct)

    • Which of the following symptoms is associated with serum sodium levels between 125 and 130 mmol/L?

    <p>Nausea</p> Signup and view all the answers

    How does cirrhosis affect plasma proteins and colloidal osmotic pressure?

    <p>Decreases colloidal osmotic pressure</p> Signup and view all the answers

    What is a common cause of hypernatremia related to fluid loss?

    <p>Dehydration due to excessive sweating</p> Signup and view all the answers

    Which condition is associated with general edema?

    <p>Cirrhosis</p> Signup and view all the answers

    What effect does aldosterone have on sodium excretion?

    <p>Increases sodium retention</p> Signup and view all the answers

    What process describes the movement of substances from blood into the nephron?

    <p>Secretion</p> Signup and view all the answers

    What is the main function of the glomerulus?

    <p>Filter blood</p> Signup and view all the answers

    Which process primarily involves the use of energy by tubular epithelial cells?

    <p>Reabsorption</p> Signup and view all the answers

    What role does chloride (Cl-) play within the extracellular fluid?

    <p>Chief counter ion of Sodium</p> Signup and view all the answers

    How does chloride maintain electroneutrality in the body?

    <p>Through the chloride shift</p> Signup and view all the answers

    What is the volume of blood filtered per minute known as?

    <p>Glomerular filtration rate (GFR)</p> Signup and view all the answers

    What describes the movement of substances from the tubular lumen to blood?

    <p>Tubular reabsorption</p> Signup and view all the answers

    What happens during tubular secretion?

    <p>Substances move from blood to tubular lumen</p> Signup and view all the answers

    What type of electrolyte moves toward the cathode?

    <p>Cations</p> Signup and view all the answers

    Which mechanism requires energy to transport ions across membranes?

    <p>Active transport</p> Signup and view all the answers

    What is one of the primary functions associated with potassium ions?

    <p>Myocardial rhythm and contractility</p> Signup and view all the answers

    What includes the ions involved in blood coagulation?

    <p>Calcium and Magnesium</p> Signup and view all the answers

    What is the passive movement of ions across a membrane called?

    <p>Diffusion/Passive transport</p> Signup and view all the answers

    What does osmolality primarily depend on?

    <p>Concentration of solutes per kilogram of solvent</p> Signup and view all the answers

    Which electrolytes are primarily involved in acid-base balance?

    <p>Bicarbonate, Chloride, and Potassium</p> Signup and view all the answers

    What effect does increased blood osmolality have on the secretion of Arginine Vasopressin Hormone (AVP)?

    <p>Stimulates secretion</p> Signup and view all the answers

    What is the primary function of chloride ions in the body?

    <p>Maintenance of water distribution</p> Signup and view all the answers

    Hypochloremia is primarily associated with which of the following conditions?

    <p>Prolonged vomiting</p> Signup and view all the answers

    Which part of the kidney actively reabsorbs chloride ions?

    <p>Loop of Henle (thick ascending limb)</p> Signup and view all the answers

    What causes hyperchloremia?

    <p>Excess loss of bicarbonate</p> Signup and view all the answers

    Which anticoagulant is preferred for chloride ion testing?

    <p>Lithium Heparin</p> Signup and view all the answers

    What does a method using coulometric generation of silver ions help to quantify?

    <p>Chloride concentration</p> Signup and view all the answers

    Patients with metabolic alkalosis often exhibit which chloride condition?

    <p>Hypochloremia</p> Signup and view all the answers

    How does hemolysis affect chloride measurement in serum or plasma?

    <p>It causes no significant change in levels.</p> Signup and view all the answers

    Which method is most commonly used for mercurimetric titration?

    <p>Ion-Selective Electrode</p> Signup and view all the answers

    What percentage of magnesium in the human body is found in bone?

    <p>53%</p> Signup and view all the answers

    What role does magnesium play in the body?

    <p>Cofactor for over 300 enzymes</p> Signup and view all the answers

    Which of the following sources is a rich source of magnesium?

    <p>Raw nuts</p> Signup and view all the answers

    What is the renal threshold for magnesium?

    <p>0.60–0.85 mmol/L</p> Signup and view all the answers

    What percentage of magnesium serum is bound to proteins?

    <p>1/3</p> Signup and view all the answers

    Which hormone increases the renal reabsorption of magnesium?

    <p>Parathyroid hormone (PTH)</p> Signup and view all the answers

    What is the end product of the mercurimetric titration using diphenylcarbazone?

    <p>HgCl2</p> Signup and view all the answers

    Study Notes

    Blood Volume Status

    • Affects sodium excretion through aldosterone, angiotensin II, and ANP.
    • Hyponatremia - loss of sodium due to an increase in water volume.

    Hyponatremia

    • One of the most common electrolyte disorders.
    • Can be assessed by the cause of the decrease or the osmolality level.
    • Defined as a serum/plasma sodium level less than 135 mmol/L.
    • Levels below 130 mmol/L are clinically significant.

    Causes of Hyponatremia

    • Dilutional:
      • SIADH (Syndrome of Inappropriate Anti-diuretic Hormone Secretion)
      • General Edema (Congestive Heart Failure, Cirrhosis, Nephrotic Syndrome)
      • Hyperglycemia
    • Artifactual:
      • Pseudohyponatremia, caused by analytical errors.
      • Hyperlipidemia
      • Hyperproteinemia
      • In vitro hemolysis

    Chloride (Cl-)

    • Major extracellular anion.
    • The only anion to serve as an enzyme activator.
    • Chief counter ion of Sodium in the extracellular fluid.
    • Concentration:
      • 103 mmol/L with median plasma and interstitial fluid concentrations.
      • 154 mmol/L inorganic anion concentration.
      • Erythrocytes (RBC): 45 to 54 mmol/L
      • Other Tissue Cells: only -1 mmol/L

    Functions of Chloride

    • Maintenance of water distribution.
    • Osmotic Pressure.
    • Anion-Cation Balance in the ECF.
    • Maintains electrical neutrality.

    Chloride Absorption

    • Chloride ions in food are almost completely absorbed from the intestinal tract.

    Chloride in Glomeruli

    • Filtered and passively absorbed with Sodium.

    Chloride in Loop of Henle (thick ascending limb)

    • Actively reabsorbed by the chloride pump.
    • Promotes passive reabsorption of Sodium.

    Hypochloremia

    • Decreased plasma concentration of Chloride.
    • Occurs with:
      • Excessive loss of Chloride from prolonged vomiting, diabetic ketoacidosis, aldosterone deficiency, or salt losing renal diseases such as pyelonephritis.
      • High serum bicarbonate concentration.
      • Compensated respiratory acidosis or metabolic alkalosis.

    Hyperchloremia

    • Increased plasma concentration of Chloride.
    • Occurs with excess loss of bicarbonate as a result of:
      • GI losses
      • Renal tubular acidosis (RTA)
      • Metabolic acidosis

    Determination of Chloride

    • Specimen: Serum or Plasma
      • Lithium Heparin: the anticoagulant of choice.
      • Whole blood samples: Consult the instrument's operation manual for acceptability.
      • Urine Analysis: 24-hour collection is the specimen of choice due to large diurnal variation.

    Chloride Methods

    • Ion-Selective Electrode (ISE):
      • Most commonly used.
      • An ion-exchange membrane selectively binds Chloride ions.
    • Amperometric-coulometric Titration:
      • Coulometric generation of silver ions (Ag+), which combine with Chloride to quantitate the Chloride concentration.
    • Mercurimetric Titration (Schales and Schales Method):
      • Indicator: diphenylcarbazone.
      • End product: HgCl2.
    • Whitehorn Titration Method:
      • Reagent: diphenylcarbazone.
      • End Product: reddish complex.

    Magnesium (Mg2+)

    • Fourth most abundant cation in the body and second most abundant intracellular ion.
    • Average human body (70 kg) contains 1 mole (24g) of Mg2+.
    • Distribution:
      • 53% in Bone
      • 46% in muscle and other organs and Soft Tissue
      • Less than 1% is present in Serum and Red Blood Cells
    • Essential cofactor of more than 300 enzymes.
      • 1/3 of serum Mg2+ is bound to a protein (Albumin).
      • Remaining 2/3:
        • 61% exists in the free or ionized state (physiologically active).
        • 5% is complexed with other ions (PO4- and citrate).

    Regulation of Magnesium

    • Absorption: Rich sources of Mg2+: raw nuts, dry cereal, “hard” drinking water, vegetables, meats.
    • Renal Threshold: ~0.60–0.85 mmol/L.
    • Factors Affecting Mg2+ levels:
      • Parathyroid hormone (PTH): Increases renal reabsorption of Mg2+ and enhances absorption in the intestine.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    Electrolytes and Fluid Balance PDF

    Description

    This quiz covers key concepts related to blood volume status and hyponatremia. Learn about how sodium excretion is influenced by various factors, the definitions and causes of hyponatremia, and the role of chloride as an extracellular anion. Understand the clinical significance of sodium levels and potential diagnostic considerations.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser