Validation of Respiration Rate Algorithms

Sponsor

Guy's and St Thomas' NHS Foundation Trust (Other)

Overall Status

Completed

CT.gov ID

NCT01472133

Collaborator

Engineering and Physical Sciences Research Council, UK (Other), University of Oxford (Other)

130

Enrollment

Location

Duration (Months)

6.5

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

Continuous accurate unobtrusive respiratory rate monitoring may lead to improved patient outcomes, as respiratory rate is thought to be a sensitive marker of patient deterioration. Currently systems are not suitable for long term monitoring, particularly in ambulant patients as they are too restrictive. To ensure that our algorithms are suitable for use in a clinical context we need to demonstrate their performance not only in the optimal situation, healthy volunteers at rest, but also in more challenging situations such as where the person being monitored is moving and also in patients who have conditions which may affect their physiology in such a way that the accuracy of the respiration rate estimation may be affected.

No previous study has systematically tested algorithms deriving respiratory rate from either the ECG or the photoplethysmography (PPG) waveforms in a real -world setting.

The algorithms work by looking for changes in intervals between heartbeats and also changes in the sizes of the ECG and PPG waveforms, both of which may be caused by respiration. These changes tend to diminish with increasing age and also conditions which alter the chest movement and cardiac reflexes. Thus it is important to test our algorithms' accuracy in participants exhibiting these conditions. It is also important to ensure that the calculations of respiratory rate are accurate across a range of heart rates and respiratory rates. Our testing covers all these variables.

Condition or Disease	Intervention/Treatment	Phase
Respiratory Rate Pulse Oximetry	Other: Recording of 12 lead ECG Other: Recording of lying and standing blood pressure Other: Recording of chest wall movement Other: Recording of heart rate variability Other: Recording of ECG and Pulse oximeter waveform at rest Other: Recording of ECG and Pulse oximeter waveform during exercise

Study Design

Study Type:

Observational

Anticipated Enrollment :

130 participants

Observational Model:

Cohort

Time Perspective:

Prospective

Official Title:

Validation of Respiration Rate Algorithms

Study Start Date :

Jun 1, 2012

Actual Primary Completion Date :

Feb 1, 2014

Actual Study Completion Date :

Feb 1, 2014

Arms and Interventions

Arm	Intervention/Treatment
Young Healthy Volunteers Healthy volunteers under the age of 40	Other: Recording of 12 lead ECG Recording of 12 lead ECG Other: Recording of lying and standing blood pressure Recording of lying and standing blood pressure Other: Recording of chest wall movement Recording of chest wall movement Other: Recording of heart rate variability Done during deep breathing and a valsalva manoeuvre Other: Recording of ECG and Pulse oximeter waveform at rest For 10 mins Other: Recording of ECG and Pulse oximeter waveform during exercise Recording of ECG and Pulse oximeter waveform during exercise
Older healthy volunteers Healthy volunteers over the age of 70	Other: Recording of 12 lead ECG Recording of 12 lead ECG Other: Recording of lying and standing blood pressure Recording of lying and standing blood pressure Other: Recording of chest wall movement Recording of chest wall movement Other: Recording of heart rate variability Done during deep breathing and a valsalva manoeuvre Other: Recording of ECG and Pulse oximeter waveform at rest For 10 mins
Patients with atrial fibrillation Patients with permanent AF	Other: Recording of 12 lead ECG Recording of 12 lead ECG Other: Recording of lying and standing blood pressure Recording of lying and standing blood pressure Other: Recording of chest wall movement Recording of chest wall movement Other: Recording of heart rate variability Done during deep breathing and a valsalva manoeuvre Other: Recording of ECG and Pulse oximeter waveform at rest For 10 mins
Patients with a pacemaker Patients who have an implanted pacemaker that is continually pacing	Other: Recording of 12 lead ECG Recording of 12 lead ECG Other: Recording of lying and standing blood pressure Recording of lying and standing blood pressure Other: Recording of chest wall movement Recording of chest wall movement Other: Recording of heart rate variability Done during deep breathing and a valsalva manoeuvre Other: Recording of ECG and Pulse oximeter waveform at rest For 10 mins
Patients with restricted chest movement Patients whose chest expansion is less than 2.5cm	Other: Recording of 12 lead ECG Recording of 12 lead ECG Other: Recording of lying and standing blood pressure Recording of lying and standing blood pressure Other: Recording of heart rate variability Done during deep breathing and a valsalva manoeuvre Other: Recording of ECG and Pulse oximeter waveform at rest For 10 mins

Outcome Measures

Primary Outcome Measures

The coefficient of variation for each respiration rate algorithm [5-6 months]
The algorithms to be tested are: one which calculates respiration rate (RR) from ECG only, one which calculates RR from PPG only, one which calculates RR from simultaneous ECG and PPG

Secondary Outcome Measures

The coefficient of variation for the respiration rate calculated from a second pulse oximeter [5-6 months]
Participants will wear two different PPG monitors to assess whether PPG monitors from different manufacturers introduce artefactual changes to the PPG morphology

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Months and Older

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Yes

Inclusion Criteria:

Young Healthy Volunteers
Participant is willing and able to give informed consent for participation in the study.
Male or Female, aged between 18 and 40 years old.
Older Healthy Volunteers
Participant is willing and able to give informed consent for participation in the study.
Male or Female, aged 70 years or above.
Patients
Participant is willing and able to give informed consent for participation in the study.
Male or Female, aged 18-70 years old.
Participant has one of the following conditions:
Atrial fibrillation
A permanent pacemaker that is continuously active
Reduced chest wall movement

Exclusion Criteria:

Young Healthy Volunteers
Any condition which might increase the risk of exercise testing
Any history of ischaemic heart disease
Any history of heart failure
Any structural heart disease (eg: valvular lesions, hypertrophic obstructive cardiomyopathy)
Any abnormalities on a resting ECG
Deep vein thrombosis diagnosed within the last 6 months or under active treatment
Uncontrolled hypertension (systolic blood pressure >220 mm Hg, diastolic >120 mm Hg)
Aortic aneurysm
Aortic or cardiovascular surgery within 6 months of recruitment
A family history of sudden cardiac death, congenital arrhythmia syndromes or cardiomyopathy
Autonomic dysfunction, either previously diagnosed or upon testing by the research team
Any condition involving the brain or spinal cord
Diabetes
Alcohol consumption > 21 units/week for women and 28 units/week for men or a history of previous alcohol dependence.
Acute kidney injury
Chronic kidney disease stage 4 or 5
Any condition causing hepatic dysfunction
Presence of a permanent pacemaker (these participants would be eligible for the pacemaker group)
Reduced chest wall movement (these participants would be eligible for the reduced chest movement group)
Any acute infection requiring antibiotic treatment within 3 months of recruitment
Any other surgery or illness requiring hospitalisation within 3 months of recruitment
Currently taking any medication with the exception of analgesics or the oral contraceptive pill.
Any wound or skin condition affecting the torso which may be affected by the application of adhesive ECG dots to the skin
Pregnancy
Inability to give informed consent
Older Healthy Volunteers
Any diagnosed condition primarily affecting the cardiovascular or respiratory systems
Symptomatic autonomic dysfunction
Orthostatic hypotension
Any condition involving the brain or spinal cord
Diabetes
Alcohol consumption > 21 units/week for women and 28 units/week for men or a history of previous alcohol dependence.
Acute kidney injury
Chronic kidney disease stage 4 or 5
Any condition causing hepatic dysfunction
Presence of a permanent pacemaker
Chronic Obstructive Pulmonary Disease (COPD).
Any muscular dystrophy
Kyphosis
Scoliosis
Pectus excavatum
Any disease involving the lungs or pleura
Any acute infection requiring antibiotic treatment within 3 months of recruitment
Any other surgery or illness requiring hospitalisation within 3 months of recruitment
Currently taking any medication with the exception of analgesics or the oral contraceptive pill.
Any wound or skin condition affecting the torso which may be affected by the application of adhesive ECG dots to the skin
Pregnancy
Inability to give informed consent
Patients
Any infection which would require isolation or barrier nursing according to the hospital's infection control policy
Any wound or skin condition affecting the torso which may be affected by the application of adhesive ECG dots to the skin
Requirement for any form of artificial ventilatory support, including oxygen therapy
More than one of the inclusion criteria. (ie: a patient may not have both atrial fibrillation and reduced chest wall movement and be eligible for this study)
Inability to give informed consent