Are there any evidence-based ways of assessing dyspnoea (breathlessness) by telephone or video

March 23, 2020

Trish Greenhalgh, Koot Kotze and Helene-Mari Van Der Westhuizen

On behalf of the Oxford COVID-19 Evidence Service Team
Nuffield Department of Primary Care Health Sciences
University of Oxford

Correspondence to trish.greenhalgh@phc.ox.ac.uk

UPDATED April 2nd 2020


VERDICT
We found no validated tests for assessing breathlessness in an acute primary care setting. We found no evidence that attempts to measure a patient’s respiratory rate over the phone would give an accurate reading, and experts do not use this test in telephone consultations. Our search identified a test which we initially considered might have potential (the Roth score), but recent anecdotal experience with COVID-19 patients suggests the tool is not sufficiently sensitive for identifying serious illness and may falsely reassure.

Pending further research, the recommendations below are based on expert opinion. A rapid survey of 50 clinicians who regularly assess patients by phone (on 20.3.20) recommended not using the Roth score (though opinions were mixed) and gave the following advice:

  1. Ask the patient to describe the problem with their breathing in their own words, and assess the ease and comfort of their speech. Ask open-ended questions and listen to whether the patient can complete their sentences.

“How is your breathing today?”

  1. Align with NHS111 symptom checker, which asks three questions (developed through user testing but not evaluated in formal research):

“Are you so breathless that you are unable to speak more than a few words?”

“Are you breathing harder or faster than usual when doing nothing at all?”

“Are you so ill that you’ve stopped doing all of your usual daily activities?”

  1. Focus on change. A clear story of deterioration is more important than whether the patient currently feels short of breath. Ask questions like

“Is your breathing faster, slower or the same as normal?”

“What could you do yesterday that you can’t do today?”

“What makes you breathless now that didn’t make you breathless yesterday?”

  1. Interpret the breathlessness in the context of the wider history and physical signs. For example, a new, audible wheeze and a verbal report of blueness of the lips in a breathless patient are concerning.

The tools and instruments and tools identified were as follows:

  1. Roth Score. This score has only been tested in one study against pulse oximetry in healthy volunteers and hospital inpatients. It has not been validated in primary care and we have received reports of significant events in which GPs were falsely reassured by a “normal” Roth score. Ask the patient to take a deep breath and count out loud from 1 to 30 in their native language. Count the number of seconds before they take another breath. If the “counting time” is 8 seconds or less, this has a sensitivity of 78% and specificity of 71% for identifying a pulse oximeter reading of <95%. If the counting time is 5 seconds or less, sensitivity is 91%. Of 50 experts, only 6 used the Roth score (most had never heard of it). Experts were concerned that if used indiscriminately and as a substitute for holistic clinical assessment in the COVID crisis, this score could lead to harm by missing patients with serious illness and increasing the number of patients called in for physical examination.
  2. Smartphone apps for oximetry: Very limited published research. This topic has been addressed in more detail in a special technical review  Question: Should smartphone apps be used as oximeters? Answer: No
  3. Oximetry devices supplied to patients. Commonly used in respiratory medicine clinics but have not yet been evaluated in a primary care setting.

Searches and critical appraisal undertaken by Dr Koot Kotze and Dr Helene-Mari Van Der Westhuizen, and expert survey by Professor Trisha Greenhalgh from University of Oxford