A-a Gradient

Pulmonary & Critical Care

Patient Ageyrs

Arterial PaCO2mmHg

Arterial PaO2mmHg

Inspired O2 (FiO2)%

Ready to Analyze

Enter arterial blood gas (ABG) values and patient age to calculate oxygenation efficiency across the alveolar membrane.

Guidelines & Evidence

Verified

Last Review: 2026-07-17

Last Comprehensive Review: 2026-07-17

WHO NewsJul 2, 2026

Clinical Context

We think this has broad domain relevance to Aa Gradient.

BJOGJun 25, 2026

Clinical Context

We think this has broad domain relevance to Aa Gradient.