*PROCEDURE*: Long term oxygen therapy

[chrisjwood16]

User Requirements*

The ISARIC COVID-19 case report form collects data on patients medical history. A detailed completion guide collects data on patients medical history. A planned ISARIC validation study requires a series of SNOMED CT codelists to replicate as closely as possible the details given in the ISARIC case report form. This codelist is designed to identify patients on long term oxygen, to be used in combination with other codelists as part "Chronic pulmonary disease".

Coding system*

SNOMED CT

Sensitivity versus specificity / Relevant definitions

Identify long term oxygen therapy users only

Definition: Long‑term oxygen therapy (LTOT) - The provision of oxygen therapy for continuous use at home, usually given for at least 15 hours during the day or night. NICE

Existing relevant codelists

Nil found

Search terms / synonyms / search strategy

• Long term oxygen therapy
• LTOT
• Oxygen
• O2
• Home oxygen

Inclusion Criteria for Codes

Codes indicating patient is:

• receiving long term oxygen

Exclusion Criteria for Codes

Codes indicating:

• oxygen therapy equipment only
• ambulatory oxygen
• oxygen of unclear duration/setting - e.g. "Patient on oxygen"
• referral for/assessment/education of oxygen therapy inc home oxygen

Borderline cases

• Number of hours long-term oxygen therapy prescribed per day(883561000000101) - excluded- unlikely to be used in isolation. 20 uses in 21/22.
• "Supplier reported volume of long-term oxygen prescribed per day" (883621000000105) - excluded- unlikely to be used in isolation. Zero uses in 21/22.
• Supplier reported volume of lont-term oxygen prescribed per day (883631000000107) - excluded- unlikely to be used in isolation. Zero uses in 21/22.

Final codelist

https://www.opencodelists.org/codelist/user/chriswood/long-term-oxygen-therapy/21ad9e89/

[speed-vm]

Hi, just couple of suggestions @chrisjwood16 :

Could add in this: Definition of Long‑term oxygen therapy (LTOT) - The provision of oxygen therapy for continuous use at home, usually given for at least 15 hours during the day or night. (NICE](https://www.nice.org.uk/guidance/qs10/chapter/Quality-statement-3-Assessment-for-longterm-oxygen-therapy) - This is helpful for borderline cases, as unlikely to be doing 15 hours exercise for example.

Just need to clarify exclusions as there are codes relating to the supply of equipment and we say we have excluded codes relating to equipment.

[chrisjwood16]

Thanks Vicky - really helpful. That definition is very useful - I've added "Relevant definitions" to the template so I remember to look for these early on in future. The definition is quite narrow so I've taken out anything that doesn't indication long-term oxygen therapy. https://www.opencodelists.org/codelist/user/chriswood/long-term-oxygen-therapy/21ad9e89/

[speed-vm]

Hi @chrisjwood16 , just one thing, Ambulatory oxygen therapy is a bit of a tricky one because it is prescribed for patients on long-term oxygen therapy who need to be away from home on a regular basis BUT Patients who are not on long-term oxygen therapy can be considered for ambulatory oxygen therapy if there is evidence of exercise-induced oxygen desaturation and of improvement in blood oxygen saturation and exercise capacity with oxygen.

Since we want to be specific then have justification to rule these out. Therefore, from my perspective happy to sign off.

[chrisjwood16]

@speed-vm - thanks. Agree ambulatory oxygen can be used by those on LTOT but they should also have a code indicating LTOT if that is the case. So ambulatory oxygen codes not included in this codelist.