What is the calculated pH for a patient sample if the measured bicarbonate concentration is 22 mEq/L and the pCO₂ is 57 mmHg?

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Quizplus · Accepted Answer

The pH can be calculated using the Henderson-Hasselbalch equation for the bicarbonate buffer system in blood: pH = pKa + log([HCO3-]/(0.03 * pCO2)). Assuming a pKa of 6.1 for carbonic acid (H2CO3) and using the given values ([HCO3-] = 22 mEq/L and pCO2 = 57 mmHg), the calculation would approximate to a pH of 7.2. This simplifies the understanding that a bicarbonate level within the normal range (22-26 mEq/L) and a slightly elevated pCO2 would result in a pH that is slightly lower than normal but still closer to the neutral pH of 7.4, making 7.2 a reasonable estimate.

What Is the Calculated PH for a Patient Sample If