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9 Posts

mitty
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Topics: 52
Posts: 376

08/11/06 - 10:38 AM

A 26-year-old woman is brought to the emergency department suffering from anxiety, tachypnea, and light-headedness. She has numbness and tingling of her hands, feet, and the circumoral area. Her arterial blood values show a pH of 7.49, PCO2 of 20 mm Hg, and HCO3¯ concentration of 19 mEq/L. The numbness and tingling sensations are most likely due to which of the following disorders?

A. Decreased serum ionized Ca2+
B. Decreased serum K+
C. Decreased serum Na+
D. Increased serum Ca2+
E. Increased serum K+

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drpkaur
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Topics: 195
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08/11/06 - 11:20 AM

Perioral tingling and parasthesia, 'pins and needles' sensation over the extremities of hands and feet. This is the earliest symptom of hypocalcemia. so is it A.

vallia
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08/11/06 - 11:29 AM

agree

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pseudomonas
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Topics: 0
Posts: 6

09/03/06 - 01:22 AM

agree, answer is A
this patient is probably normocalcemic and as pH rises not total serum Ca++ but only serum ionized Ca++ decreases as Ca++ dissocotaion decreases

Leopard
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09/03/06 - 05:21 PM

pseudomonas wrote:
agree, answer is A
this patient is probably normocalcemic and as pH rises not total serum Ca++ but only serum ionized Ca++ decreases as Ca++ dissocotaion decreases

Absolutely correct Pseudomonas

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young_doc
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09/05/06 - 03:30 PM

The sign & symptoms are non-specific, and can pretty much occur with any electrolyte imbalance.

The decrease in H (increase in pH) can also directly causes a decrease in K (due to the H/K antiports...).

Why not Hypokalemia? (which, like i said, can also present with neuropathies...). Anyone?

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Leopard
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09/05/06 - 04:57 PM

Hypokalemia causes paresthesias ?????????????

Reference please

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jole
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Topics: 12
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09/05/06 - 05:55 PM

This woman has a respiratory alkalosis and in this condition the decreased H+ conc leads decreased binding of this cation to negatively charged plasma proteins therefore Ca2+ binds to these plasma proteins thus decreasing the conc of ionized calcium and causing hypocalcemia and the symptoms associtaed with it.Correct me if am wrong please.

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new_n_lost
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09/05/06 - 06:45 PM

Yes the woman has Respiratory Alkalosis the ans is A

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