Version 2.80

Term Description

The arterial/alveolar oxygen tension ratio, also known as a/APO2, is a measure of gas-exchange. While it was originally believed to be less affected by the fraction of inspired oxygen (FiO2) compared to other measures such as the alveolar-arterial oxygen tension difference (PAO2-PaO2), the a/APO2 has been found to be somewhat dependent on FiO2, especially with higher degrees of pulmonary shunting. PMID: 3742320

Fully-Specified Name

Component
Oxygen.arterial/Oxygen.alveolar
Property
PPresRto
Time
Pt
System
BldA+Resp.alv
Scale
Qn
Method
Calculated

Additional Names

Long Common Name
Arterial-alveolar oxygen Partial pressure ratio
Short Name
a/A PO2 Rto

Basic Attributes

Class
PULM
Type
Clinical
First Released
Version 2.54
Last Updated
Version 2.73 (MIN)
Order vs. Observation
Both
Common Test Rank Get Info
6140

Formula (Readable)

a/APO2=PaO2/PAO2, where PaO2 is arterial partial pressure of oxygen and PAO2 in alveolar partial pressure of oxygen

Language Variants Get Info

Tag Language Translation
el-GR Greek (Greece) Οξυγόνο.αρτηριακό/Οξυγόνο.κυψελιδικό:PPresRto:Pt:Αρτηριακό+κυψελιδικό.οξυγόνο:Qn:Υπολογιζόμενο
Synonyms: PPresRto Οξυγόνο Οξυγόνο.αρτηριακό
es-MX Spanish (Mexico) Oxígeno.arterial / Oxígeno.alveolar:PPresRto:Punto temporal:BldA + Resp.alv:Cuantitativo:Calculated
fr-CA French (Canada) Oxygène.Artériel/Oxygène.Alvéolaire:PPresRatio:Temps ponctuel:Sang artériel+Système respiratoire.alvéolaire:Quantitatif:Calculé
it-IT Italian (Italy) Ossigeno.arterioso/Ossigeno.alveolare:Rapporto di pressione parziale:Pt:Sangue arterioso+sistema respiratorio alveolo:Qn:Calcolato
Synonyms: Gestione ventilazione polmonare Ossigeno arterioso Punto nel tempo (episodio) Sangue arterioso
zh-CN Chinese (China) 氧.动脉/氧.肺泡:分压比率:时间点:动脉全血+呼吸系统.肺泡:定量型:计算法
Synonyms: O2;tO2;总氧;氧气 分压（分压力、分压强、气体分压、部分压力、局部压应力）比率（比、比值、比例） 动脉全血（动脉血）+呼吸系统.肺泡 动脉血 可用数量表示的;定量性;数值型;数量型;连续数值型标尺 时刻;随机;随意;瞬间 氧（氧气）.动脉 氧（氧气）.肺泡 肺部测量指标与呼吸机管理 计算;计算型方法

Example Units

Unit Source
{ratio} Example UCUM Units

LOINC Terminology Service (API) using HL7® FHIR® Get Info

CodeSystem lookup
https://fhir.loinc.org/CodeSystem/$lookup?system=http://loinc.org&code=78354-8