Acid-Base Balance Physiology MCQs (for FCPS Part 1)

The MCQs in this post are taken from the book “FCPS Pretest Series – Physiology”. If you want to purchase this book, send us a personal message on our official page by clicking here.

 

 

Candidates find acid-base balance (ABGs) quite difficult; at the end of this post, you must be able to easily answer MCQs related to acid-base Physiology.
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1. Anion gap increases in:

a. Uncontrolled DM

b. Diabetes insipidus

c. Bronze diabetes

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Ans. A

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ANION GAP

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DEFINITION: The anion gap is the difference between primary measured cations (sodium Na+ and potassium K+) and the primary measured anions (chloride Cl- and bicarbonate HCO3-) in serum.

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CALCULATING ANION GAP

Anion Gap=Na+KClHCO3

Anion gap=140+410824=12

So, normally anion gap = 8 – 12

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WHY DO WE GET ANION GAP: Normally, anions (-ve chages) in plasma are equal to cations (+ve charges). So, anion gap should be zero but we get an anion gap of 8 – 12 because of unmeasured anions (especially the negatively charged proteins).

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SIGNIFICANCE OF ANION GAP: The anion gap is used to diagnose the cause of metabolic acidosis as anion gap is increased in some cases (e.g., diabetic ketoacidosis) while it is normal in others (diarrhea, renal tubular acidosis type 1 and type 2).

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Use the following mnemonics to remember elevated and non-elevated gap metabolic acidoses:

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MUDPILES (elevated gap)

HARDUP (non-elevated gap)

M: Methanol

H: Hyperchloremia (parental nutrition)

U: Uremia (kidney failure)

A: Acetazolamide

D: Diabetic ketoacidosis

R: Renal tubular acidosis

P: Paraldehyde

D: Diarrhea

I: Iron; Isoniazid

U: Ureteral diversion

L: Lactic acidosis

P: Pancreatic fistula

E: Ethylene glycol; ethanol ketoacidosis

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S: Salicylates; starvation ketoacidosis; sepsis

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WHY DM INCREASES ANION GAP: In uncontrolled DM, the body cells are unable to use glucose as an energy source due to the lack of insulin or its resistance. So, to get energy, the body breaks down lipids into fatty acids which are converted to acetyl Co.A and then to ketones in the liver. As ketones are acidic, they result in acidosis (diabetic ketoacidosis), and acidosis causes accumulation of anions (negative ions), which results in increased anion gap.

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2. Anion gap is increased in all except:

a. Lactic acidosis

b. Ketoacidosis

c. Salicylate poisoning

d. Distal renal tubular acidosis

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Ans. D. Anion gap is not elevated in those cases of metabolic acidosis where the primary disorder is “loss of HCO3”. This is because the loss of negatively charged HCO3 is replaced by increased absorption of negatively charged chloride, thus having no effect on anion gap. The two most important cases of metabolic acidosis in which anion gap is not increased are: (1) Diarrhea (2) Renal tubular acidosis (type 1 and type 2) .

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3. The following condition is not associated with an increased Anion – Gap type of metabolic acidosis:

a. Shock

b. Ingestion of ante-freeze

c. Diabetic ketoacidosis

d. COPD

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Ans. D. Increased anion gap occurs only in metabolic acidosis, while COPD causes respiratory acidosis.

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4. The anion gap is filled by the following substances except

A. Beta hydroxy butyric acid

B. Bicarbonate

C. Phosphates

D. Poly anionic plasma proteins

E. Sulfate

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Ans. A

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5. The anion gap is decreased in

A. Hypoalbuminaemia

B. Ketoacidosis

C. Lactacidosis

D. Metabolic alkalosis

E. Salicylate poisoning

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Ans. A

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6. Patient with severe vomiting presented with breathlessness, PH=7.5, HCO3=32 PCO2=55. Diagnosis is

a. Metabolic alkalosis

b. Metabolib acidosis

c. Compensatory’ etabolic alkalosis

d. Respitory alkalosis

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Ans. C

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Normal Values

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Ph = 7.35 – 7.45 (Average = 7.40)

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PCo2 = 36 – 44 (Average = 40)

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HCO3 = 22 – 26 (Average = 24)

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DIAGNOSING ACID-BASE ABNORMALITIES

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Use the 3 questions to quickly determine acid-base abnormalities.

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Question 1: What is the osis?

 

Look at pH:

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  • If pH <7.35, then it’s acidosis.
  • If pH >7.45, then it’s alkalosis.

 

Question 2: What is the cause of the osis?

Follow the bicarbonate:

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  • If the answer to question 1 is acidosis and HCO3- is elevated, then respiratory acidosis.
  • If the answer to question 1 is acidosis and HCO3- is low, then metabolic acidosis.
  • If the answer to question 1 is alkalosis and HCO3- is low, then respiratory alkalosis.
  • If the answer to question 1 is alkalosis and HCO3- is elevated, then metabolic alkalosis.

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Question 3: Was there compensation?

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  • In metabolic disturbance, respiratory compensation occurs (i.e., Pco2 is not in the normal range)
  • In respiratory disturbance, metabolic compensation occurs (i.e., HCo3 is not in the normal rang

 

(A) METABOLIC ACIDOSIS:

If there is metabolic acidosis, and PCo2 is less than normal, then compensation has occurred. If compensation has occurred but Ph is not in the normal range, then the compensation is “partial”. If compensation has occurred and Ph is in the normal range, then it is “fully” compensated.

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(B) METABOLIC ALKALOSIS: 

 

If there is metabolic alkalosis and Pco2 is above normal, then compensation has occurred. If Ph is not in the normal range, then it is “partial” compensation. If Ph is in the normal range, it is “fully” compensated.

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(C) RESPIRATORY ACIDOSIS:

 

In respiratory acidosis, if HCo3 is above normal, then compensation has occurred. If Ph is not in normal range, it is “partial” compensation. If Ph is in normal range, it is “fully” compensated.

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(D) RESPIRATORY ALKALOSIS: 

 

In respiratory alkalosis, if HCo3 is below normal, then compensation has occurred. If Ph is not in the normal range, then compensation is “partial”. If Ph is in the normal range, then it is “fully” compensated.

 

Image result for acid base balance

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EXPLANATION OF MCQ

 

(1) Ph is ↑sed, so it is alkalosis. (2) HCO3 is ↑sed, so it is metabolic alkalosis. (3) PC02 is ↑sed, so it is compensated metabolic alkalosis. (4) Ph is not in the normal range, so it is partially (and not fully) compensated metabolic alkalosis.

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7. In chronic renal failure (equivalent to a reduction in the total Number of nephrons)

A. Anemia when it occurs tends to be of the iron deficiency type

B. Plasma Pco2 tends to be low

C. The amount of ionized calcium in the blood rises due to calcium retention

D. The specific gravity of the urine is typically high (e.g. 1030)

E. Water intake should be restricted to about 0.5 liters per day

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Ans. B. CRF causes metabolic acidosis due to retention of acids (such as phosphates, sulphates). As a compensation to metabolic acidosis, the patient has hyperventilation which decreases plasma Pco2 and increases plasma Po2. Decrease in plasma Pco2 tends to increase Ph towards normal.

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8. A year old man is admitted via the emergency room with Advanced peritonitis. His investigations include arterial blood Gas analysis. This shows Ph 7.25, HCo3 12.4 mmol/L, PCo2 33.9 mmHg, Base excess -14.3 mmol/L, Po2 82.8 mmHg. Which of the following is the most likely cause

A. Metabolic acidosis with some respiratory compensation

B. Metabolic alkalosis uncompensated

C. Normal arterial blood gases

D. Respiratory acidosis uncompensated

E. Respiratory acidosis with compensatory metabolic alkalosis

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Ans. A. (1) Ph is below normal, so it is acidosis. (2) HCo3 is below normal, so it is metabolic acidosis. (3) Pco2 is below normal, so there is respiratory compensation. (4) Ph is not in the normal range, so compensation is partial.

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9. An uncontrolled diabetic presents in emergency with Respiratory rate of 34/min. Abg’s show compensated metabolic Acidosis. The laboratory result which matches the condition is

A. Ph – 7.2, pco2 – 60, hco3 – 26

B. Ph – 7.36, pco2 – 20, hco3 – 14

C. Ph – 7.36, pco2 55, hco3 – 30

D. Ph – 7.4, pco2 – 40, hco3 – 23

E. Ph – 7.46, p002 – 28. Hco3 – 20

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Ans. B. (1) If it is metabolic acidosis, the HCo3 should be below normal (< 24). (2) If it is compensated, the PCo2 should be below normal (< 36).

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10. Acidosis occurs due to following conditions except

A. Chronic renal failure

B. Prolonged vomiting

C. Pulmonary fibrosis

D. Severe diarrhea

E. Uncontrolled diabetes mellitus

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Ans. B. Vomiting causes loss of K+ and H+, resulting in hypokalemia and metabolic alkalosis.

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11. The most important buffer in interstitial fluid is

a. H2CO3

b. Hb

c. Plasma protein

d. PO4.

Ans. A. The table below shows most important buffers (must be memorized well, as they are important).

 

Question

Answer

Most imp. Buffer of the whole body

 Bicarbonate (HCo3)

Most imp. Buffer of ECF

 Bicarbonate

Most imp. Buffer of the blood

 Bicarbonate

Most imp. Buffer of interstitial fluid

 Bicarbonate

Most imp. Buffer of ICF

 Proteins (Not Hemoglobin)

Most imp. Buffer of CSF

 Bicarbonate

Most imp. Urinary buffer

 Phosphate

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1

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12, Most important buffer of extracellular fluid and body is

a. Protein

b. Hb

c. Hco3

d. Phosphate

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Ans. C

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13. Principle buffer of interstitial fluid is

a. Haemoglobin

b. Carbonic acid

c. H2PO4

d. Other proteins

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Ans. B. Carbonic acid (H2Co3) combines with H20 to form HCo3- and H+; HCo3- is the most important buffer of interstitial fluid.

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14. Most common Intracellular buffer is

a. Haemoglobin

b. Proteins

c. Bicarbonate

d. Phosphate

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Ans. B

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15. The most important buffering system in the body is

A. Bone

B. Hco3

C. Hemoglobin

D. Phosphate

E. Plasma proteins

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Ans. B

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16. Regarding heamoglobin, true is

A. Does not carry CO2

B. Acts as a buffer

C. Contains 2 alpha and 2 gamma chains

D. Contain less iron than myoglobin

E. All are true

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Ans. B

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17. What is true about Hb.

A. Consists of alpha and gamma chains in Adults

B. Important buffer of H+

C. Not associated with CO2 transport

D. Also found in wbc

E. Also contains silver

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Ans. B

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18. A Buffer system in the body fluids;

A. Consists of a strong base and its salt

B. Consists of a strong acid and its salt

C. Is more powerful if its concentration is less.

D. Is more powerful if Pk is near to the ph of the body fluid

E. Tends to prevent completely any change in ph when an acid or base added.

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Ans. D

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19. A 54 year old man was hospitalized with congestive heart failure. The blood gas Laboratory reports revealed arterial ph 7.52, paco2 44mmhg, Hco3 34meq/L. A venous Co2 measured at the same time was 26,meq/L. What is his Most likely acid-base status

A. Carbon monoxide (CO) poisoning

B. Metabolic acidosis

C. Metabolic alkalosis

D. Respiratory acidosis

E. Respiratory alkalosis

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Ans. C

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20. Emphysema may lead to acid-base imbalance. It is characterized By

A. Fall in [hi+ ions concentration in plasma

B. Fall in plasma bicarbonate

C. Positive base excess

D. Rise in plasma Pco2

E. Rise in plasma ph

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Ans. D. Emphysema is a COPD disease. In all COPD diseases, there is obstruction to outflow. So, Co2 remains in alveoli and blood, resulting in high alveolar and blood Pco2, which in turn results in respiratory acidosis.

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21. A 45 years old woman, 4 hours after open cholecystectomy has Depressed consciousness, cynosis with respiratory rate of 8/min. Her blood gas values are ph ‘7.24, p02 75, pco2 60, hco3 24. The diagnosis for this patient is

A. Metabolic acidosis

B. Metabolic alkalosis

C. Normal acid base status

D. Respiratory acidosis

E. Respiratory alkalosis

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Ans. D

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22. An Asthmatic patient with following ABGs: Ph 7.32, PCO2 48, HCO3 25 has

a. Respiratory acidosis with metabolic compensation

b. Respiratory acidosis without metabolic compensation

c. Respiratory alkalosis without metabolic compensation

d. Respiratory alkalosis with metabolic compensation

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Ans. B. (1) Ph is ↓sed, so it is acidosis. (2) Pco2 is ↑sed, so it respiratory acidosis. (3) HCO3 is in the normal range, so it is uncompensated respiratory acidosis.

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23. Renal main compensation in respiratory alkalosis is

a. Decrease production of ammonia

b Increase NaHCO3 secretion

c. Increased acid secretion

d. lncreased Hco3 absorption

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Ans. B. (A) ↑HCO3 EXCRETION: Inside the renal tubular cells, Co2 and H20 combine to form H2Co3, which then splits into H+ and HCO3; H+ is secreted into the tubular fluid (and then excreted) while HCO3 is absorbed into the circulation.

In respiratory alkalosis, CO2 ↓ses, less CO2 is available for H2CO3 production, so less H2CO3 is formed in tubular cells, which results in ↓ed production of H+ and HCO3. This results in ↓ed excretion of H+ and ↓ed reabsorption of HCO3 (↑HCO3 excretion), thus ↓ing body PH. The opposite is true for respiratory acidosis.

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(B) ↑Na EXCRETION: In late DCT and collecting ducts, Aldosterone reabsorbs Na and secretes K+ and H+.

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In alkalosis, the ↑sed Ph ↓ses H+ ions. As a compensatory mechanism, positively charged H+ comes out into the blood from the cells to decrease Ph of the body. As a result, the positively charged K+ moves into the cells from the blood to maintain electrical neutrality. So, the plasma K+ level decreases, resulting in hypokalemia. In hypokalemia, aldosterone secretion decreases, so less Na is reabsorbed (more Na excreted), and so less H+ and K+ is secreted (and excreted), thus ↓ing body Ph. The opposite events occur in respiratory acidosis.

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24. A person has Ph 7.48, CO2 66 and HCO3 27 . What is the diagnosis

a. Acute respiratory acidosis

b. Acute metabolic acidosis

c. Partially compensated respiratory acidosis

d. Partially compensated metabolic acidosis

e. Partially compensated metabolic alkalosis

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Ans. E. (1) Ph is ↑ed, so it is alkalosis. (2) HCO3 is ↑ed, so it is metabolic alkalosis. (3) Pco2 is ↑ed, so it is compensated metabolic alkalosis.

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25. ABG analysis of a patient on ventilator shows decreased pC02, normal Po2, Ph 7.5. Diagnosis is:

a. Respiratory acidosis

b. Metabolic alkalosis

c. Respiratory alkalosis

d. Metabolic acidosis

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Ans. C. (1) Ph is increased, so it is alkalosis. (2) Pco2 is decreased, so it is respiratory alkalosis.

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26. 1n metabolic acidosis which of the following changes are seen

a. Increased K+ excretion

b. Increased K+ reabsorption from tubules

c. Increased Na+ excretion

d. Increased Na+ reabsorption

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Ans. D. [Option A] – K+ and H+ compete with each other for secretion in late DCT, and collecting ducts. In acidosis, H+ increases, so more H+ is secreted, and hence less K+ is secreted.

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[Option B] – As a compensatory mechanism, the positively charged H+ from the blood enter the cells to decrease body Ph, so the positively charged K+ move out from the cells into the blood to maintain electrical neutrality in the cell. So, the plasma level of K+ increases, leading to hyperkalemia. So, as a compensatory mechanism, K+ reabsorption in the kidneys decreases.

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[Option C+D] – Acidosis results in hyperkalemia, and hyperkalemia is the most potent stimulus for aldosterone secretion. Aldosterone reabsorbs Na+, and secretes K+ and H+ in late DCT, and collecting ducts.

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27.A patient having head injury with shallow breathing and his respiratory rate and pulse were 11/min and 96/min respectively. What would be the likely finding in his arterial blood gases.

a. Decreased pH, decreased 02, decreased CO2

b. Decreased pH, decreased 02, increased CO2, increased HCO3

c. Decreased pH decreased 02, increased CO2

d. Increased Ph ,decreased 02,increased CO2

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Ans. C. (1) Ph and Co2: Normal respiratory rate is 15/min. This patient’s respiratory rate is less than normal. So, he is having hypoventilation. In hypoventilation, all the CO2 in the blood can not be exhaled, so Pco2 increases in the blood. As CO2 is acidic, ↑Co2 results in ↓body Ph.

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(2) Oxygen: Due to hypoventilation, less oxygen comes to alveoli, and hence, less oxygen comes to the blood. So, the oxygen level decreases in the blood.

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28. Arterlal blood gases of patient show Ph=7.1, Pco2=44, HCO3=12(Normal values are pH = 7.36 — 7.44, PCO2 = 36-44 mmHg, HCO3 = 22-26 mEq/L). What is the most likely diagnosis:

a. Metabolic acidosis

b. Respiratory alkalosis

c. Partially compensated metabolic acidosis

d. Respiratory acidosis

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Ans. A. (A) Ph is decreased, so it is acidosis. (2) HCO3 is decreased, so it is metabolic acidosis. (3) Pco2 is normal, so it is uncompensated metabolic acidosis.

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29. A plumber comes to emergency center with shortness of breath. His blood testing reveals Po2 = 62 mmHg, Pco2 = 31 mmHg, HCO3 = 19mEq/L, Ph = 7.4. What is the most likely diagnosis

a. Compensated respiratory alkalosis

b. Compensated metabolic alkalosis

c. Metabolic alkalosis

d. Respiratory alkalosis

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Ans. A. (1) Ph is in the normal range, so it is either normal or compensated. (2) Pco2 is decreased, so it respiratory alkalosis. (3) HCO3 is decreased, so it is compensated respiratory alkalosis.

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30. Male patient was brought to the ER with critical condition. ABGs showed PH 7.25 .PCO2 65 and HCO3 24.

a. Acute Respiratory Acidosis

b. Respiratory alkalosis

c. Partially Compensated Respiratory Acidosis

d. Partially Compensated Respiratory Alkalosis

e. Respiratory and metabolic Acidosis

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Ans. A. (1) Ph is decreased, so it is acidosis. (2) PCo2 is increased, so it is respiratory acidosis. (3) HCO3 is normal, so it is uncompensated respiratory acidosis.

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31. A 30 year old man was brought to the hospital with the history Of drug intake. His respiratory rate was 6 breaths per minute. His Arterial ph was 7.3. The most likely change expected in arterial Blood analysis is

A. Changed H2C03/HCO3- ratio

B. Decreased HCO3- level

C. Increased Po2

D. Normal HCO3- level

E. Normal Pco2

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Ans. A

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32. Diagnostic feature of metabolic alkalosis in arterial blood is

A. Hco3 greater than 24 meq/L

B. Increased serum carbonic anhydrase

C. P002 less than 24 meq/L

D. P02 less than 60

E. Ph less than 7.4

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Ans. A. Metabolic alkalosis results from ↑Hco3 (Hco3 > 26).

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33. Metabolic alkalosis is a serious threat to homeostasis. The diagnostic feature of metabolic alkalosis is

A. Hco3 > 24 meq/L in blood (arterial)

B. Increased serum carbonic anhydrase

C. Pco2 < 24 meq/L in blood (arterial)

D. Vomitus having high alkaline contents

E. Ph < 7.4 of blood

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Ans. A

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34. A 50 year old smoker presented with cough and breathlessness. He is drowsy. Labs show pH 7.2, pCO2 60, pO2 55, bicarb 27, Na 134, K 3.8. Most likely diagnosis is
a. Compensatory respiratory acidosis
b. Metabolic acidosis
c. Respiratory acidosis and metabolic alkalosis
d. Respiratory alkalosis and metabolic acidosis
e. Uncompansated respiratory acidosis

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Ans. E

35. Patient presented in ER with dyspnea; Ph =6 7.13. Cot = 55 mm hg, hco3 = 26 mmol/l, po2 = 49 mm hg; He is k/c of COPD, what is most likely diagnosis?

A. Respiratory acidosis

B. Respiratory alkalosis

C. Respiratory acidosis with type-1 respiratory failure

D. Fully compensated respiratory acidosis

E. Respiratory acidosis with type-2 respiratory failure

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Ans. E

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36. In uncompensated metabolic alkalosis
A. the plasma pH, the plasma HCO3– concentration, and the arterial Pco2 are all low.
B. the plasma pH is high and the plasma HCO3– concentration and arterial P co2 are low.
C. the plasma pH and the plasma HCO3– concentration are low and the arterial P co2 is normal.
D. the plasma pH and the plasma HCO3– concentration are high and the arterial P co2 is normal.
E. the plasma pH is low, the plasma HCO3– concentration is high, and the arterial P co2 is normal.

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Ans. D. (1) In alkalosis, Ph is always high. (2) In alkalosis is “metabolic”, HCo3 will always be higher than normal (> 26). (3) If respiratory compensation has not occurred in metabolic acidosis/metabolic alkalosis, it means that there is normal ventilation and hence, Po2 and Pco2 will be normal.

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37. In a patient with a plasma pH of 7.10, the [HCO3– ]/[H2 CO3 ] ratio in plasma is
A.20.
B.10.
C.2.
D.1.
E. 0.1.

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Ans. B

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38. To obtain a reasonable idea of the acid-base state of a Patient’s blood, you would need to know serum levels of

A. Paco2 and Hco3

B. Paco2 and pa02

C. Paco2 and Sa02

D. Ph and Pa02

E. Ph and Sa02

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Ans. A. Paco2 tells about respiratory acidosis/alkalosis while Hco3 tells about metabolic acidosis/alkalosis.

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39. The finding which is not likely to be present in metabolic Acidosis is

A. Acidic urine

B. Hyperkalemia

C. Increased plasma bicarbonate

D. Increased pulmonary ventilation

E. Low Ph of the blood

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Ans. C. Plasma Hco3- decreases in respiratory as well as metabolic acidosis, and increases in respiratory as well as metabolic alkalosis.

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40. You are presented with a patient in whom you suspect Compensated metabolic acidosis. Which of the lab data Given below confirm your suspicion: Hco3 Pco2 Ph

A. 17 30 7.3

B. 19 19 7.5

C. 20 40 7.3

D. 24 45 7.4

E. 34 30 7.6

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Ans. A. (1) Ph is 7.3, which means that it is not in the normal range, so it is “partially” compensated (THE STEM IS TRICKY HERE). (2) HCo3 is less than normal (17), so it is metabolic acidosis. (3) Pco2 is less than normal (30), so respiratory compensation has occurred.

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41. A 65 year old male was brought to the emergency in critically ill condition. His acid-base profile revealed: ph 7.08 (7.35-7.45), Pco2 (mmhg) 66 (35-45), Hco3 (mmol/l) 18 (23-29). What is the most Likely biochemical diagnosis

A. Metabolic acidosis

B. Metabolic acidosis with respiratory acidosis

C. Partially compensated metabolic acidosis

D. Partially compensated respiratory acidosis

E. Respiratory acidosis

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Ans. B. (1) Ph is less than normal, so it is acidosis. (2) HCo3 is less than normal, and Pco2 is above normal, so it is mixed respiratory + metabolic acidosis.

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42. A 65 year old female had chronic obstructive airway disease. She develops fever and later on septicemia due to salmonella Infection. Her acid-base profile revealed Ph 7.37 (7.35-7.45), pco2 (mmhg) 48 (35-45) HCo3 (mmol/l) 30 (23-29). The most likely Biochemical diagnosis is

A. Fully compensated respiratory acidosis

B. Metabolic acidosis with metabolic alkalosis

C. Metabolic acidosis with respiratory alkalosis

D. Respiratory acidosis with metabolic alkalosis

E. Respiratory acidosis with respiratory alkalosis

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Ans. D

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43. A 26 year old young man reports in OPD of DHQ skardu, who Happen to be a high lander. Patient complains of shortness of Breath, rapid breathing, blueness of fingers and confusion. On Investigations, it revealed RBC count=6.4 millions/dl, PCV=55%, Arterial Pco2=20mmhg, plasma Hco3=25meq/l. He is most likely Suffering from

A. Acute bronchial asthma

B. Metabolic alkalosis

C. Respiratory alkalosis

D. Respiratory distress syndrome

E. Secondary polycythemia

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Ans. C

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44. A 65 year old male was brought to the emergency in Critically ill condition. His acid base profile revealed: ph 7.08 (normal 7.35 – 7.45) pco2 66 (normal 35 – 45 mmhg) hco3 18 (normal 23 – 29 mmol/l). What is the most likely biochemical Diagnosis?

A. Metabolic acidosis and respiratory acidosis

B. Non compensated metabolic acidosis

C. Non compensated respiratory acidosis

D. Partially compensated metabolic acidosis

E. Partially compensated respiratory acidosis

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Ans. A

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45. In chronic renal failure, which of the statements is correct?

A. Anemia when it occurs tends to be of the iron deficiency type

B. Plasma Pco2 tends to be low

C. The amount of ionised calcium in the blood rises due to calcium retention

D. The specific gravity of the urine is typically high

E. Water intake should be restricted to about 0.5 litre per day

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Ans. B. CRF causes metabolic acidosis. As a compensatory mechanism, hyperventilation occurs which results in ↑Po2 and ↓PCo2.

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46. The anion gap is filled by the following substances except

A. Beta hydroxy butyric acid

B. Bicarbonate

C. Phosphates

D. Poly anionic plasma proteins

E. Sulfate

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Ans. A

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