Question 1

Atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) are released into the bloodstream from the ______ and are used clinically to evaluate the possibility of ______.&#10;A)heart, congestive heart failure&#10;B)brain, hydrocephalus&#10;C)heart, myocardial infarction&#10;D)brain, congestive heart failure

Accepted Answer

ANP and BNP are released from the heart in response to excessive stretching of heart muscle in the presence of increased blood volume.BNP (brain natriuretic peptide) is named as such because it was originally identified in extracts of porcine brain.In humans, BNP is found in the heart.Natriuretic peptides have their greatest clinical utility in identifying the presence of congestive heart failure.

Question 2

Given the following patient results, which statement is true?
Sodium = 136 mEq/L
Potassium = 4.3 mEq/L
Chloride = 99 mEq/L
Bicarbonate = 22 mEq/L
Measured serum osmolality = 283 mOsm/kg
Glucose = 288 mg/dL
BUN = 45 mg/dL

A)The electrolytes are in balance, and the value obtained for osmolality correlates with the other data.
B)The electrolytes are not in balance, but the value obtained for osmolality correlates with the other data.
C)The electrolytes are in balance, but the value obtained for osmolality does not correlate with the other data.
D)The electrolytes are not in balance, and the value obtained for osmolality does not correlate with the other data.

Accepted Answer

The anion gap for the data is 15 mEq/L, which indicates that the electrolytes appear to be in balance.The calculated osmolality is 285 mOsm/kg, which correlates with the measured serum osmolality.

Question 3

Which of the following describes the correct meaning of anion gap = 15 mEq/L?&#10;A)There is a 15 mEq/L gap between the major measured cations and major measured anions.&#10;B)There is a 15 mEq/L gap between the physiologically active cations in the body and the physiologically active anions in the body.&#10;C)There are 15 mEq/L more cations than anions in the plasma sample tested.&#10;D)There are 15 mEq/L more anions than cations in the plasma sample tested.

Accepted Answer

The sum of all cation charges in plasma must equal the sum of all anion charges in order to maintain electroneutrality.Of all of the cations and anions present, four ions are routinely measured in a clinical laboratory.These include sodium, potassium, chloride, and bicarbonate.Since laboratory data are usually available for these ions, the use of the concentration/activity of these four ions can be used to provide a general assessment of ionic balance in the body by calculating the anion gap.The anion gap is calculated by taking the difference between the sum of the major measured cations and the sum of the major measured anions.An anion gap of 15 mEq/L means that the major measured cations exceed the major measured anions by 15 mEq/L.Thus the unmeasured anions must exceed the unmeasured cations to maintain electroneutrality.The left-hand bar graph illustrates the normal balance between ions, along with the anion-gap calculation.The right-hand bar graph illustrates an increased anion gap.In this example, the increase in unmeasured anions causes a decrease in measured anions to maintain electroneutrality.The increase in unmeasured anions comes from the lactate anions (labeled organic acid in the figure), which is coupled with a decrease in bicarbonate (which is a measured anion included in the anion-gap calculation).

Question 4

The following data represent four consecutive serum electrolyte patterns obtained from a multichannel analyzer.What should inspection of these data (in mEq/L) suggest?&#10; &#10;A)The anion gap suggests that systematic error exists.&#10;B)A high anion gap for patient 2 is seen because of a low chloride level.&#10;C)Data show no reason for concern; results should be reported.&#10;D)Data indicate significant variation; results should not be reported until results are verified.

Accepted Answer

The concept of anion gap was initially developed as a quality control check when it was noted that the gap was typically around 7 mEq/L (using the equation that does not consider potassium).A calculated anion gap outside the range of 7 to 16 mEq/L suggests the presence of an error in measurement.For these data, all show an anion gap of 10 to 14 mEq/L.Thus the patient results should be reported.

Question 5

A sweat chloride of 70 mEq/L is indicative of which of the following diseases?&#10;A)cystic fibrosis&#10;B)myasthenia gravis&#10;C)Cushing's syndrome&#10;D)syndrome of inappropriate ADH secretion

Accepted Answer

Cystic fibrosis is associated with a change in excretions in specific areas of the body.These include the liver, lungs, and sweat glands.In cystic fibrosis, the sodium and chloride levels typically increase from a normal of approximately 40 mEq/L to approximately 70 mEq/L or greater.

Question 6

Acute metabolic acidosis resulting from acid with an associated anion promotes an increase in the plasma level of which electrolyte?&#10;A)sodium&#10;B)potassium&#10;C)chloride&#10;D)bicarbonate

Accepted Answer

In metabolic acidosis, as the acid (H⁺) moves into the red blood cell to be buffered by hemoglobin, potassium (K⁺) moves out of the red blood cell to maintain electroneutrality.

Question 7

Insulin release will stimulate cellular uptake of which of the following electrolytes?&#10;A)sodium&#10;B)potassium&#10;C)chloride&#10;D)bicarbonate

Accepted Answer

Insulin stimulates the cellular uptake of potassium by hepatocytes and muscle cells by inducing an increase in Na,K-ATPase activity.This action of insulin on potassium is independent of its action on glucose.

Question 8

Which of the following electrolytes is likely to be found decreased in metabolic alkalosis?&#10;A)sodium&#10;B)potassium&#10;C)chloride&#10;D)bicarbonate

Accepted Answer

Metabolic alkalosis results from an excess of bicarbonate.As bicarbonate increases, chloride will decrease to maintain electroneutrality.

Question 9

Which electrolyte is most significantly affected by hemolysis?&#10;A)sodium&#10;B)potassium&#10;C)chloride&#10;D)bicarbonate

Accepted Answer

Potassium is approximately 30 times more concentrated inside the red blood cell than in plasma.Thus the presence of visible hemolysis will be associated with a significant increase in potassium levels.

Question 10

The urine level of which electrolyte will distinguish excess diuretic use or self-induced vomiting from Barter's syndrome?&#10;A)sodium&#10;B)potassium&#10;C)chloride&#10;D)bicarbonate

Accepted Answer

With chronic diuretic use or protracted vomiting, urinary chloride levels are usually below 20 mEq/L.Patients with Barter's syndrome always have elevated urine chloride levels.

Question 11

The renin-angiotensin-aldosterone system is initiated by the release of renin from which organ?&#10;A)brain&#10;B)lungs&#10;C)liver&#10;D)kidney

Accepted Answer

The answer of The renin-angiotensin-aldosterone system is initiated by the...

Question 12

Which of the following changes will be seen in dehydration?
1)increase in aldosterone
2)increase in antidiuretic hormone
3)increase in atrial natriuretic peptide

A)1, 2, 3
B)1, 2
C)2, 3
D)1, 3

Accepted Answer

The answer of Which of the following changes will be...

Question 13

As the concentration of macromolecules such as lipids and proteins increases:&#10;A)methods that measure ions in plasma water will show an increase in the concentration/activity measured, although the physiological activity is normal.&#10;B)methods that measure ions in plasma water will show a decrease in the concentration/activity measured, although the physiological activity is normal.&#10;C)methods that measure ions in total plasma volume will show an increase in the concentration/activity measured, although the physiological activity is normal.&#10;D)methods that measure ions in total plasma volume will show a decrease in the concentration/activity measured, although the physiological activity is normal.

Accepted Answer

The answer of As the concentration of macromolecules such as...

Question 14

A normal serum osmolality is:&#10;A)150 - 350 mOsm/kg&#10;B)247 - 263 mOsm/kg&#10;C)285 - 298 mOsm/kg&#10;D)325 - 348 mOsm/kg

Accepted Answer

The answer of A normal serum osmolality is:&#10;A)150 - 350...

Question 15

Given the following laboratory data, calculate the anion gap.
Sodium = 133 mEq/L
Potassium = 4.9 mEq/L
Chloride = 98 mEq/L
Bicarbonate = 20 mEq/L

A)5 mEq/L
B)10 mEq/L
C)15 mEq/L
D)20 mEq/L

Accepted Answer

The answer of Given the following laboratory data, calculate the...

Question 16

Which of the following laboratory results will be seen with the increased release of ANP and BNP?
1)Urine sodium level will increase.
2)Antidiuretic hormone level will increase.
3)Aldosterone level will decrease.

A)1, 2, 3
B)1, 2
C)2, 3
D)1, 3

Accepted Answer

The answer of Which of the following laboratory results will...

Question 17

The combination of hyponatremia and hypo-osmolality could be caused by which of the following?&#10;A)adrenocortical insufficiency such as hypoaldosteronism&#10;B)excessive vomiting and diarrhea&#10;C)syndrome of inappropriate ADH secretion (SIADH)&#10;D)both a and c

Accepted Answer

The answer of The combination of hyponatremia and hypo-osmolality could...

Deck 28: Physiology and Pathophysiology of Body Water and Electrolytes