What does this LOINC code represent?

This LOINC code identifies a lab observation, measurement, question, or clinical concept in a standardized format.

Is this enough to understand my test result?

No. The code identifies the test or observation, but the interpretation depends on the actual result, reference range, and clinical context.

LOINCActiveObservation

LOINC Code 20280-4: Pressure half time by US+Calculated

Name: LOINC Code 20280-4: Pressure half time by US+Calculated
Creator: HealthAssure Clinical Team
Published: 2026-05-21T11:17:28.846Z

20280-4 is a LOINC code used to identify Pressure half time by US+Calculated in laboratory and clinical observation data. You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges. LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Pressure half time.XXX. It is commonly used with the system or sample type Circulatory system.XXX.

Reviewed by HealthAssure Clinical TeamUpdated 21 May 2026

What is this code?

LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Pressure half time.XXX. It is commonly used with the system or sample type Circulatory system.XXX.

When is it used?

Used in lab systems, EHRs, and clinical data exchange.
May identify a test, observation, survey item, or clinical document request rather than a diagnosis.
Status: ACTIVE
Order vs observation: Observation
Method: US+Calculated

What it does not mean

The code identifies the observation or test, not the actual result.

Key facts

Pressure half time by US+Calculated
Pressure half time.XXX
Calc; Calculation; CARD.US; Cardio; Cardiology; Circ; Circ sys; Echography; Heart Disease; Misc; Miscellaneous; Other; P1/2T; PHT; Point in time; QNT; Quan; Quant; Quantitative; Random; Sonogram; Sonograph; Sonography; Spec; T1/2; To be specified in another part of the message; ULS; Ultrasound; Unspecified; US Calc

Where you may see this code

You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges.

Common synonyms

Pressure half time by US+CalculatedPHT US+CalcPressure half time.XXXCARD.USTimePtCirculatory system.XXX

Frequently asked questions

Code details

Code20280-4

SystemLOINC

Display namePressure half time by US+Calculated

DescriptionPressure half time.XXX

Short namePHT US+Calc

ComponentPressure half time.XXX

PropertyTime

TimingPt

System (specimen)Circulatory system.XXX

ScaleQn

MethodUS+Calculated

ClassCARD.US

Example unitsms

StatusACTIVE

Order/ObservationObservation

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released1.0m

Last changed2.54

Part names

Pressure half time.XXXTimePtCirculatory system.XXXQnUS+CalculatedTime (e.g. seconds)Point in time (spot)Circulatory system XXX

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from LOINC. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.