LOINCActiveObservation

LOINC Code 45358-9: Length of calorie fast [Time]

45358-9 is a LOINC code used to identify Length of calorie fast [Time] 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 Length of calorie fast. It is commonly used with the system or sample type ^Patient.

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 Length of calorie fast. It is commonly used with the system or sample type ^Patient.

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

What it does not mean

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

Key facts

  • Length of calorie fast
  • Number of hours patient was fasting before specimen drawn for analysis
  • Cal; Calories; Len; Length of Fast; MISC; Point in time; QNT; Quan; Quant; Quantitative; Random

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

Length of calorie fast [Time]Length of calorie fastLength of Fast Time PatientMISCTimePt^Patient

Frequently asked questions

Code details

Code45358-9
SystemLOINC
Display nameLength of calorie fast [Time]
DescriptionLength of calorie fast
Short nameLength of Fast Time Patient
ComponentLength of calorie fast
PropertyTime
TimingPt
System (specimen)^Patient
ScaleQn
ClassMISC
Example unitsH
StatusACTIVE
Order/ObservationObservation

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released2.17
Last changed2.73

Consumer names

Length of calorie fast

Part names

Length of calorie fastTimePt^PatientQnTime (e.g. seconds)Point in time (spot)

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.

LOINC Code 45358-9 | HealthAssure