Main Menu

Q.1- A 64 year-old man who develops acute renal failure while recovering from a severe acute myocardial infarction (Acute MI), Blood chemistry reveals:

Na+ 140 mEq/L, K+ 4 mEq/L, Cl115 mEq/L, CO2 5 mEq/L, pH = 7.12, PaCO2 13 mmHg, and HCO34 mEq/L. Calculate the anion gap and then choose the best answer  for acid-base status.

A) His anion gap of 14 indicates he has metabolic alkalosis

B) His anion gap of 20 is conclusive of a respiratory acidosis.

C) His anion gap of 22 strongly suggests a respiratory alkalosis

D) His anion gap of 21 is conclusive of high anion gap metabolic acidosis

E) His anion gap of 25 is conclusive of normal acid base status.

Q.2- A 48-year-old man with bronchiectasis presents to the hospital emergency room with 3 days of increasing cough, sputum, and dyspnea. About 1 month ago, his arterial blood gas analysis showed pH 7.38, PaO2 55 mmHg, PaCO2 65 mmHg, and HCO332 mEq/L. His current vital signs are BP 117/65 mmHg, Pulse 123/min, Temperature 100°F. His current ABG(Blood gas analysis) in the Emergency Room is pH 7.28, PaCO2 70 mmHg, PaO2 50 mmHg, and HCO323 mEq/L. Which of the following best characterizes the current acid-base status?

A) Compensated metabolic acidosis

B) Compensated metabolic alkalosis

C) Uncompensated metabolic acidosis

D) Uncompensated respiratory acidosis

E) Uncompensated respiratory alkalosis

Q.3- A hospital patient with AIDS has diarrhea and becomes hypovolemic within a short period of time. Which of the following laboratory results would best fit this clinical history?

A) pH: 7.15, pCO2: 55 mmHg, HCO3: 40 mEq/L

B) pH: 7.25, pCO2: 36 mmHg, HCO3: 15 mEq/L

C) pH: 7.40, pCO2: 40 mmHg, HCO3: 24 mEq/L

D) pH: 7.50, pCO2: 28 mmHg, HCO3: 24 mEq/L

E) pH: 7.35, pCO2: 40 mmHg, HCO3: 24 mEq/L.

Q.4- A 50-year-old chronic alcoholic is brought to the emergency room in a semiconscious state. Blood pressure is 100/50 mmHg, heart rate 120 beats/min, respiratory rate 35/min, and his temperature is 104F (40C).

Blood chemistry reveals : Sodium 150mEq/L (135-145), Potassium 2.5mEq/L (3.5-5.0), Chloride 107mEq/L (95-105),Bicarbonate 10mEq/L (24-26), pH 7.2 (7.35-7.45), PCO2 25mmHg (35-45), Alcohol 40mmol/L (0), Osmolality 370mOsm/L (280-295), Glucose 50mg/dl (60-110) BUN 40mg/dl (5-22). What is the acid-base status?

A) Metabolic acidosis

B) Metabolic Alkalosis

C) Respiratory acidosis

D) Respiratory alkalosis

E) Metabolic acidosis with respiratory compensation

Q.5-All of the following statements are correct about potassium balance, except:

A) Most of potassium is intracellular.

B) Three quarter of the total body potassium is found in skeletal muscle.

C) Intracellular potassium is released into extra-cellular space in response to severe injury.

D) Acidosis leads to movement of potassium from extracellular to intracellular fluid compartment.

E) Aldosterone promotes excretion of potassium and reabsorption of sodium.

Q.6- Normal anion gap metabolic acidosis is caused by all except:

A) Cholera

B) Starvation

C) Ethylene glycol poisoning.

D) Lactic acidosis

E) Methanol poisoning.

Q.7- Which of the following is more appropriate for a 17-year-old Female suffering from IDDM with the following blood chemistry report:

pH: 7.2,  PO2 : 108 mm Hg, PCO2 : 12 mmHg and HCO3 : 5 meq/L

A) Metabolic Acidosis with respiratory alkalosis

B) Respiratory Acidosis

C) Metabolic Alkalosis

D) Respiratory alkalosis

E) Metabolic alkalosis with respiratory alkalosis

Q.8- A middle-aged person collapsed on the road side and was brought to emergency, Blood chemistry revealed the following:

pH- 7.51, PCO2– 35 mm Hg, PO2- 62mm Hg and HCO3-27 meq/L.

Which of the following is the most appropriate acid base imbalance in the above said condition?

A) Metabolic acidosis

B) Metabolic alkalosis with respiratory acidosis

C) Respiratory alkalosis with metabolic compensation

D) Respiratory acidosis

E) Metabolic alkalosis with respiratory alkalosis.

Q.9- A 24 –year female reported to the emergency with difficulty in breathing. History revealed that she had ingested some unknown drug. The blood chemistry revealed the following:

PH-7.1; PCO2– 55 mm Hg; PO2-42 mm Hg and HCO317 meq/L

Which of the following is the most appropriate acid base imbalance in the above said condition?

A) Metabolic acidosis with respiratory acidosis

B) Respiratory acidosis

C) Respiratory Alkalosis

D) Metabolic alkalosis

E) None of the above.

Q.10- Which of the following is incorrect about minimum excretory volume?

A) The exact quantity depends on the concentrating power of the kidney

B) The exact quantity depends on the quantity of the solute load

C) The urinary volume is approximately 500 to 600 ml in 24 hrs

D) It is the minimum volume of urine excreted to eliminate the “waste products” of metabolism.

E) It is the amount of urine excreted per day in normal health.

Q.11- The anion gap is calculated as follows: 

A) [K+] + [HCO3– + Cl]

B) [Na+] + [Cl + HCO3]
C) [Na+] – [HCO3– + Cl]

D) [Na+] + [K+]-[Cl- + HCO3]

E) None of the above.

Q.12- ADH release is stimulated by any of the following except:

A) Increased serum osmolality

B) Increased blood volume

C) Decreased Blood pressure

D) Stress

E) Hyponatremia

Q.13- Which of the following is not a cause of pure salt depletion?

A) In mental patients who refuse to drink

B) Excessive sweating

C) Renal failure

D) Mineralocorticoid deficiency

E) Chronic diarrhea

Q.14- Hypokalemia is serum K concentration < 3.5 mEq/L and is caused by:

A) Renal losses

B) GI losses

C) Diuretics

D) Insulin administration

E) All of the above.

Q.15- – Hyponatremia is decrease in serum Na concentration < 136 mEq/L and is caused by :

A) Diuretic use

B) Crush injuries

C) Hemolysis

D) High fever

E) None of the above.

Q.16- Serum sodium concentration is regulated by:

A) Stimulation of thirst,

B) Secretion of ADH,

C) Renin-angiotensin-aldosterone system,

D) Variations in renal handling of filtered sodium

E) All of the above.

Q.17- Factors that shift Potassium in or out of cells include the following:

A) Blood glucose concentration

B) Blood volume

C) Acid-base status

D) Serum Sodium concentration

E) All of the above.

Q.18- Which of the following is not a cause of hyperkalemia?

A) Acute renal failure

B)  Trauma

C) Metabolic acidosis

D) Respiratory alkalosis

E) Intake of bananas.

Q.19- The Henderson-Hassel Balch equation is represented as-

A) pH = pKa + log (A/HA)

B) pH = pKa + log (HA/A)

C) pH = pKa – log(A/HA)

D) pH = pKa – log(HA/A)

E) pH = pKa + log(H+/HA)

Q.20- All are true for renal handling of acids in metabolic alkalosis except

A) Hydrogen ion secretion is decreased

B) Bicarbonate reabsorption is decreased

C) Urinary acidity is decreased

D) Urinary ammonia is decreased

E) Renal Glutaminase activity is increased.


Key to answers

1)- D, 2)- D, 3)-B, 4)- E, 5)-D, 6)-A, 7)- A, 8)-E, 9)-A, 10)-E, 11)-C, 12)- B, 13)-A,14)-E, 15)- A, 16)- E, 17)- E, 18)- D, 19)- A, 20)-E.


Please help "Biochemistry for Medics" by CLICKING ON THE ADVERTISEMENTS above!