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Old 08-23-2012
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Question Acid-base disturbance interpretation

A 60-year-old woman complains of persistent breathing difficulties. Her laboratory studies show:
pH = 7.39
[H+] = 44 nmol/L
PaCO2 = 55 mm Hg
[HCO3-] = 32 mmol/L
Which of the following is the most likely diagnosis?

a) Primary metabolic acidosis and primary respiratory acidosis
b) Primary respiratory acidosis and primary metabolic alkalosis
c) Primary respiratory acidosis, secondary metabolic alkalosis, partial pH compensation
d) Pure metabolic acidosis without pH compensation
e) Pure respiratory acidosis
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Old 08-23-2012
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i guess it's c) primary resp.acidosis secondary met. alkalosis...with partial ph compensation...
as renal compensation is much delayed,i'm guessing it as secondary.....i'm not sure though
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Old 08-23-2012
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id go wt c too..
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Old 08-23-2012
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Default c) Primary respiratory acidosis, secondary metabolic alkalosis, partial pH compensation

Diagnosis of Acid Base Disturbance

Nice acid base question.
Have a look.
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Old 08-24-2012
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Default correct answer

The answer is b) Primary respiratory acidosis and primary metabolic alkalosis

The acid and base components are both higher than normal (normal PaCO2 = 35–45 mm Hg; normal HCO3– = 22–28 mmol/L); thus, an acid-base imbalance must exist. The pH is within normal limits (7.35–7.45). Full compensation rarely, if ever, occurs with a single acid-base disorder. Therefore, the patient most likely has a primary respiratory acidosis (PCO2 55 mm Hg) and primary metabolic alkalosis (HCO3– 32 mEq/L) causing the pH to be in the normal range. A common example of this type of blood gas is a patient with chronic bronchitis (respiratory acidosis) who is taking a loop diuretic (metabolic alkalosis) for congestive heart failure.

as for C - These laboratory studies show a primary respiratory acidosis and primary metabolic alkalosis. If partial compensation was present, the pH would not be in the normal range.
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Old 08-24-2012
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Correct Answer

pH = 7.39 Normal (range7.35-7.45)
PaCO2 = 55 mm Hg Resp acidosis (>45mmhg)
[HCO3-] = 32 mmol/L metabolic alkalosis(>28 mmol/L)

CONCLUSION
b) Primary respiratory acidosis and primary metabolic alkalosis

(p.s thank you casandra for posting awesome questions on regular basis ,i am sure we all forum members learn alot from it)
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Old 08-24-2012
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Default

Quote:
Originally Posted by offpiste View Post
pH = 7.39 Normal (range7.35-7.45)
PaCO2 = 55 mm Hg Resp acidosis (>45mmhg)
[HCO3-] = 32 mmol/L metabolic alkalosis(>28 mmol/L)

CONCLUSION
b) Primary respiratory acidosis and primary metabolic alkalosis

(p.s thank you casandra for posting awesome questions on regular basis ,i am sure we all forum members learn alot from it)
I'm glad you find it beneficial believe me, I learn a lot from those qs too
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