Aa Gradient

A-a Gradient Calculator

Patient age* :
(*Will be used to calculate normal A-a gradient based on age)
PB (Local barometric pressure) in mmHg: mmHg
PaO2 (partial pressure of arterial O2) from ABG: mmHg
PaCO2 (partial pressure of arterial CO2) from ABG: mmHg
FiO2 (fraction of inspired oxygen):

 Program Information


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Story DA. Alveolar oxygen partial pressure, alveolar carbon dioxide partial pressure, and the alveolar gas equation.
Anesthesiology. 1996 Apr;84(4):1011. 

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All calculations must be confirmed before use. The authors make no claims of the accuracy of the information contained herein; and these suggested doses are not a substitute for clinical judgement. Neither GlobalRPh Inc. nor any other party involved in the preparation of this program shall be liable for any special, consequential, or exemplary damages resulting in whole or part from any user's use of or reliance upon this material.PLEASE READ THE DISCLAIMER CAREFULLY BEFORE ACCESSING OR USING THIS SITE. BY ACCESSING OR USING THIS SITE, YOU AGREE TO BE BOUND BY THE TERMS AND CONDITIONS SET FORTH IN THE DISCLAIMER.   Read the disclaimer
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