Wednesday, October 12, 2005

Acid-Base Disorders
Price: Pathophysiology, 6th Edition
Study Questions Chapter 22

1.
Acid-base balance in the human body is maintained by controlling the concentration of:
A.Blood
B.Hydrogen ions
C.Carbon dioxide
D.Oxygen

2.
An acid can best be explained as:
A.An anion
B.A cation
C.A chemical that is able to donate a H+ ion
D.A chemical that combines with a hydrogen ion to form an acid

3.
The normal pH of the blood serum indicates that the serum is:
A.Neutral
B.Slightly acid
C.Slightly alkaline
D.None of the above

4.
Normally the pH of human blood serum is:
A.7.38 to 7.42
B.7.31 to 7.42
C.7.35 to 7.48
D.7.35 to 7.55

5.
The normal [H+] of the blood is:
A.16 mEq/L
B.35 mEq/L
C.40 mEq/L
D.63 mEq/L

6.
The Henderson-Hasselbalch equation reveals that maintaining a normal pH requires that the ratio of base bicarbonate to carbonic acid must be:
A.20:1
B.1:20
C.2:20
D.30:2

7.
Three body systems act to maintain the blood pH near 7.4 and defend against large deviations. Choose the series below that lists these three systems in order, from the fastest acting to the slowest acting.
A.Kidneys, lungs, blood buffers
B.Blood buffers, lungs, kidneys
C.Blood buffers, kidneys, lungs
D.Lungs, blood buffers, kidneys

8.
The lowest limit of blood pH at which a person can live more than a few minutes is approximately:
A.6.0
B.6.8
C.7.2
D.7.3

9.
The first step in the assessment of the acid-base status is:
A.Review the clinical history for disease processes that might lead to an acid-base disturbance
B.Examine the PaCO2
C.Examine at the laboratory report of the base excess because it always leads to the right conclusion about acid-base disturbances
D.Calculate the anion gap

10.
The rapid or prolonged administration of normal saline may cause:
A.Metabolic alkalosis
B.Metabolic (Cl-) acidosis
C.Dehydration
D.Hypoventilation

11.
Diarrhea from a colostomy will cause metabolic acidosis. The primary reason that this acid-base imbalance occurs is a:
A.Primary HCO-3 deficit
B.Primary HCO-3 excess
C.Primary H2CO3 excess
D.Primary H2CO3 deficit

12.
The primary defect in respiratory acidosis is:
A.Primary HCO-3 deficit
B.Primary HCO-3 excess
C.Primary H2CO3 excess
D.Primary H2CO3 deficit

13.
A person who has a condition in which the production of endogenous organic acids (e.g., diabetic ketoacidosis) is increased above the normal level will develop:
A.Respiratory acidosis
B.Respiratory alkalosis
C.Metabolic alkalosis
D.Normal anion gap metabolic acidosis
E.High anion gap metabolic acidosis

14.
A not uncommon method of providing a feeling of euphoria, often expressed as "being high," is to deliberately hyperventilate. Hyperventilation causes an acid-base imbalance called:
A.Respiratory acidosis
B.Respiratory alkalosis
C.Metabolic acidosis
D.Metabolic alkalosis

15.
Indiscriminate administration of oxygen can be deadly for the patient with COPD (chronic bronchitis and emphysema). Which of the following sequences describes the progression of adverse effects? 1. Hypoventilation 2. Depression of the respiratory center 3. CO2 retention 4. CO2 narcosis (coma)
A.1 → 2 → 3 → 4
B.2 → 1 → 3 → 4
C.3 → 4 → 2 → 1
D.4 → 3 → 1 → 2

16.
To reduce the risk of metabolic alkalosis, nasogastric suction tubes should be irrigated with:
A.Tap water
B.Normal saline

17.
A 31-year-old man was admitted to the hospital in a coma with a diagnosis of brain tumor. A tracheostomy was performed on the day of admission and pressure-controlled mechanical ventilation given continuously. His temperature has ranged between 102° and 103.4° F. On the fifth day after admission, you note that he has carpopedal spasms of the hands when you check his blood pressure. Which of the following statements best explains this phenomenon?
A.The patient's elevated temperature has induced a neuromuscular irritability and a febrile convulsion is imminent.
B.Serum pH has decreased because of respiratory acidosis produced by hypoventilation. The decreased pH in turn caused irritability of the nervous system.
C.Serum pH has increased because of respiratory alkalosis produced by hyperventilation. The alkalosis directly stimulates the nervous system and also causes a decrease in ionized serum Ca++. Consequently, hyperirritability of the nervous system occurred.
D.Total serum calcium has decreased because of the patient's immobility and its consequent loss in the urine.

18.
The IV fluid of choice to treat a patient with metabolic alkalosis and a fluid volume deficit secondary to vomiting over several days is:
A.Lactated Ringer's solution (metabolized to HCO-3)
B.D5W
C.Normal saline
D.Normal saline with added KCl

19.
A 60-year-old widow has been in the hospital for several days for a complete medical checkup. She is worried that she may have cancer, although all tests have been negative. Her physician has diagnosed her case as an anxiety reaction following the death of her husband (from cancer). In the middle of the night, she calls the nurse into her room and complains of muscle cramps in her feet and a prickling sensation in her fingers and toes. The nurse notes that she sighs frequently. Her hands are cold and clammy to the touch and she has a slight tremor. The probable difficulty is:
A.Respiratory alkalosis
B.Respiratory acidosis
C.Metabolic acidosis
D.Metabolic alkalosis

20.
Intervention(s) that might help relieve the symptoms of the patient in question #19 include: (More than one answer may be correct.)
A.Offering her the antacid of her choice
B.Elevating the head of her bed to improve ventilation
C.Having her breathe into a paper bag
D.Offering her reassurance and allowing her to discuss her fears

21.
The clues to a mixed acid-base disturbance are: (More than one answer may be correct.)
A.Undercompensation or overcompensation of a primary acid-base disorder
B.Failure to balance the expected compensation formula
C.The change in the anion gap does not equal the change in the HCO-3
D.A large anion gap

22.
Which of the following are classified as blood buffers? (More than one answer may be correct.)
A.Bicarbonate-carbonic acid system
B.Hemoglobin
C.Phosphate
D.Protein

23.
Factors that contribute to the maintenance of metabolic alkalosis include: (More than one answer may be correct.)
A.K+ depletion
B.Na+ excess
C.Cl- depletion
D.Fluid volume deficit and secondary hyperaldosteronism

24.
Cl--responsive metabolic alkalosis is caused most often by vomiting or diuretics, and urine Cl- is less than 10 mEq/L.
True False

25.
HCO-3 and Cl- have a direct relationship: when HCO-3 increases Cl- also increase.
True False

26.
The basic cause of respiratory acidosis is hyperventilation.
True False

27.
Laboratory values alone are usually sufficient to recognize acid-base disturbances.
True False

28.
Kussmaul breathing in a patient with metabolic acidosis indicates that the lungs are attempting to compensate for the disturbance.
True False

29.
Match the cause(s) of acid-base disturbance with the type of primary acid-base disturbance.
1.High anion gap metabolic acidosis
2.Respiratory alkalosis
3.Chronic respiratory acidosis
4.Acute respiratory acidosis
5.Hyperchloremic metabolic acidosis
6.Metabolic alkalosis

1 2 3 4 5 6
A.Diarrhea

1 2 3 4 5 6
B.Renal failure; Uncontrolled diabetes; Starvation; Salicylate poisoning

1 2 3 4 5 6
C.Nasogastric suction or vomiting; Loop or thiazide diuretic; Secondary hyperaldosteronism

1 2 3 4 5 6
D.Laryngospasm

1 2 3 4 5 6
E.COPD

1 2 3 4 5 6
F.Emotional stress; Mechanical ventilation

30.
Match the likely cause(s) of mixed acid-base disturbance with the type of mixed acid-base disturbance.
1.Metabolic acidosis and respiratory alkalosis
2.Acute-on-chronic respiratory acidosis
3.Metabolic acidosis and respiratory acidosis
4.Metabolic alkalosis and respiratory acidosis
5.Metabolic alkalosis and respiratory alkalosis

1 2 3 4 5
A.Cardiopulmonary arrest

1 2 3 4 5
B.Hyperventilating chronic heart failure patient treated with diuretics; COPD patient placed on mechanical ventilator

1 2 3 4 5
C.Salicylate intoxication

1 2 3 4 5
D.COPD patient receiving nasogastric suction

1 2 3 4 5
E.COPD patient who develops pneumonia

1 comment:

Bonnie Boss said...

1b, 2c, 3c, 4a, 5c, 6a, 7b, 8b, 9a, 10b, 11a, 12c, 13e, 14b, 15b, 16b, 17c, 18d, 19a, 20cd, 21abc, 22abcd, 23acd, 24T, 25F, 26F, 27F, 28T, 29 a5 b1 c6 d4 e3 f2, 30 a3 b5 c1 d4 e2