What is the value of community oximetry monitoring in people with SARS-CoV-2? – A prospective, open-label clinical study

33 views • May 14, 2021


Author Name


Jane Wilcock

General Practitioner at Silverdale Medical Practice

Field of Study: Medicine , Published 4 Projects

COVID-19 SARS-CoV-2 Covid-19 Hypoxia Oximetry

Ciaran Grafton-Clarke

Clinical Education Fellow at the University Hospitals Leicester NHS Trust

Field of Study: Medicine , Published 1 Project

COVID-19 SARS-CoV-2 Hypoxia Oximetry

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In people with COVID-19, hypoxia at the time of admission is known to be related to mortality. Monitoring of oxygen saturations (SpO2) is therefore an increasingly common part of community-based care, with the aim of improving the identification of adults who are deteriorating. We set out to investigate whether rigid SpO2 triggers, or absolute change in SpO2, is more indicative of deterioration in COVID-19.


A prospective, uncontrolled, open-label study in a large UK general practice was conducted between May and November 2020. Participants recorded twice daily oximetry and symptom diary for 14 days after test-confirmed COVID-19. Primary outcomes were the proportion of people whose SpO2 dropped to ≤ 94% and ≤ 92%, the average maximum reduction in SpO2, and admission to hospital. We also investigated the relationship between MRC Dyspnoea scale, modified Roth score, and SpO2 through correlation analyses.


52 participants were recruited, following which 41 participants completed the study. The average age was 45.9 years with 63.4% identifying as female. The mean maximum reduction in SpO2 was 2.8%. The average time to maximum reduction in SpO2 was 6.4 days. Nine participants (22.0%) had a reduction in SpO2 to ≤94%. Three of these had a reduction in SpO2 to ≤92%, for which all three were admitted to hospital. Modified Roth score and SpO2 were weakly positively correlated (.31). MRC dyspnoea scale score and SpO2 were moderately negatively correlated (-.53).


A reduction in SpO2 to ≤92% was found to be highly predictive for admission to hospital. Modified Roth score or MRC dyspnoea scale scores should not be used as proxy measures for oximetry. This study contributes to the ongoing narrative around community-based oximetry and provides insight and recommendations for those currently engaging in or planning to roll out similar schemes.

Strengths and limitations of this study

  • This study is pragmatically designed to answer an important clinical question in primary care.
  • This study focused on previously published values of SpO2 for triggering escalation of care and therefore provides answers based on current clinical practice.
  • 11 of the 52 patients who were recruited into the study did not return their oximeter or oximetry diary at the end of the study period.
  • We did not validate the accuracy or reliability of the oximetry / symptom diaries, as these were self-completed by the participants themselves.
  • Other than admission to hospital and mortality within the study period, no other clinical outcomes have been recorded.

Funding statement 

This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

Competing interests 

Jane Wilcock has no competing interests to declare.

Ciaran Grafton-Clarke has no competing interests to declare.

Tessa Coulson has no competing interests to declare.

Competing Interest Statement 

The authors have declared no competing interest.

Clinical Trial

Independent UK GP research not registered. HRA IRAS project ID: 283310 Ethics review: 20/HRA/2326

Clinical Protocols 


Funding Statement 

Funded by chief investigator 

Author Declarations  

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.


The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

HRA ethics committee approval 20/HRA/2326

All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived.


I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).


I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable.


COVID-19 19 Projects
SARS-CoV-2 17 Projects
Hypoxia 1 Project
Oximetry 1 Project