LOINC
Version 2.68

91980-3Specific airway resistance by Plethysmograph body boxActive

Part Description

LP310432-2   Specific resistance.airway
Specific airway resistance (sRaw) reflects airway resistance (Raw) that has been adjusted for lung volume. It is measured by plethysmography during normal breathing (i.e., tidal breathing), does not require special maneuvers, and is independent of height and sex, so it is commonly used in pediatrics and can be used for children as young as 2. The relationship between sRaw and Raw is: sRaw = Raw * TGV, where TGV is thoracic gas volume. There are different methods used for calculating sRaw from the data gathered during plethysmography, including:
1. sRtot (total specific resistance), which uses the flow measurements at the maximum change in pressure
2. sRaw Vmax, which uses the the measurements at the maximum flow
3. sRaw0.5, which uses the measurements where the flow reaches 0.5 L/s
Specifying the method used to calculate sRaw is important for interpreting the results.
[PMID: 16002957] Source: Regenstrief LOINC

Fully-Specified Name

Component
Specific resistance.airway
Property
FldResist
Time
Stdy^mean
System
Respiratory system.airway
Scale
Qn
Method
Plethysmograph.body box

Additional Names

Short Name
sRaw Plethysmography

Basic Attributes

Class
PULM
Type
Clinical
First Released
Version 2.66
Last Updated
Version 2.67
Change Reason
Release 2.67: FORMULA: Added alternate formulas based on functional residual capacity measured by plethysmograph body box
Order vs. Observation
Both

Formula (Readable)

Multiple calculation methods: sRaw = Raw * TGV; sRaw = Raw * FRCpleth; sRaw = Raw * (FRCpleth + VT/2); where sRaw is specific airway resistance, Raw is airway resistance, TGV is thoracic gas volume, FRCpleth is functional residual capacity measured by plethysmograph body box, and VT is tidal volume.

Language Variants Get Info

zh-CNChinese (CHINA)
特异性阻力.气道:液体阻力:检查过程持续时间^平均值:呼吸系统.气道:定量型:体积描记器.体箱计
it-ITItalian (ITALY)
Resistenza specifica.vie aeree:FldResist:Studio^media:Apparato respiratorio.vie aeree:Qn:Pletismografo.body box

Example Units

Unit Source
cm[H2O].s Example UCUM Units

LOINC FHIR® API Example - CodeSystem Request Get Info

https://fhir.loinc.org/CodeSystem/$lookup?system=http://loinc.org&code=91980-3