Question

Chemistry Case

Ricky, a 70- year-old man with a history of chronic obstructive pulmonary disease (COPD) and respiratory infections, was admitted to the ER (just for the purposes of this case study) with a chronic cough and extreme dyspnea. He complained that he was unable to climb stairs or anything else that required any exertion. He had been a heavy smoker since his teens. The nurse noted his temperature was 101.2^oF. See Table 2A and 2B.

Table 2A: Arterial Blood Gas Results on Admission

	Ricky	Reference Range
pH	7.230	7.35-7.45
PCO2	75.0	35-45 mm Hg
PO2	28.2	83-108 mm Hg
HCO3	32.7	22-28 mEq/L
SaO2	49.6	95-98%
COHb	8.6	Nonsmokers: 0.5-1/5% Smokers: 1-2 packs/day, 4-5%. More than 2 packs/day, 8-9%

Abbreviations: COHb, carboxyhemoglobin; PCO₂, partial pressure of carbon dioxide; PO₂, partial pressure of oxygen; SaO₂, oxygen saturation, arterial

Questions

1. What are the abnormal blood gas values above and state whether they are increased or decreased?

2. What is Ricky’s acid-base status (normal, acidosis, or alkalosis)?

3. Is the condition that is responsible for the blood gases respiratory, metabolic/nonrespiratory, or mixed? Explain your answer.

4. Is the condition accurate or chronic? In other words, it is uncompensated, partially compensated, or fully compensated? Why?

5. Questions:
   1. What organ(s) is/are the primary compensatory mechanism in this acid-base disorder?
   2. List 3 processes it uses to compensate for the acid-base imbalance
   3. What other system is responsible for compensatory mechanisms in acid-base disorders? How does it compensate?
   4. why is it often inefficient in this acid-base disorder?

6. Would the oxyhemoglobin dissociation curve be shifted? If yes, what direction (right or left)? And explain why.

7. Briefly describe base excess and base deficit. Would this patient have a base excess, base deficit, or normal base?

8. Name 5 conditions which are associated with this acid-base disorder?

9. Which condition is the most likely explanation in this case?

10. What is the probable cause of the elevated temperature?

11. Briefly discuss what is meant by COPD.

Six hours later, the arterial blood gases (ABGs) in Table 2B were reported.

Table 2B: ABG results 6 hours postadmission

	Lionel R..	Reference Range
pH	7.38	7.35-7.45
PCO2	60.0	35-45 mm Hg
PO2	78.2	83-108 mm Hg
HCO3	36.2	22-28 mEq/L
SaO2	90.6	95-98%
COHb	3.6	Nonsmokers: 0.5-1/5% Smokers: 1-2 packs/day, 4-5%. More than 2 packs/day, 8-9%

12. What is Lionel’s acid-base status at this point?

Answer 1

1)What are the abnormal blood gas values above and state whether they are increased or decreased?

pH :decreased

PCO2 :increased

PO2:decreased

HCO3:increased

SaO2:decreased

COHb:increased

2)What is Ricky’s acid-base status (normal, acidosis, or alkalosis)?

acidosis, the PH is decreased

3)Is the condition that is responsible for the blood gases respiratory, metabolic/nonrespiratory, or mixed? Explain your answer.

respiratory,

4)Is the condition accurate or chronic? In other words, it is uncompensated, partially compensated, or fully compensated? Why?

it is fully compensated

full compensation has occured if the ph is in normal range of 7.35 to 7.45