Thora-3Di™ Respiratory Rate Validation

Summary

Respiratory rate (RR) is a vital sign used to monitor clinical condition of a patient. Various devices using different techniques are available to measure RR. One technique, capnography, uses continuous monitoring of expired gases, via a nasal cannula to assess end tidal CO2 concentration. This long-established technique is frequently used for patients in intensive care. Both RR and the shape of the capnogram waveform, which has a wave pattern marked by alternating inspiratory and expiratory phases, are used to help monitor the patient. Clinician Over-scored End Tidal C02 (COSC) waveform (whereby an expert identifies and scores each breath on the waveform and counts the number of breaths per minute) is considered to be a "gold standard" for measuring RR.

Being able to record RR, without contact or interference with the patient is appealing because it requires minimal patient co-operation, enables measurements even during acute respiratory conditions, and may be more representative of "real life" physiology. Based on a principle originally described in the 1980s, a novel instrument that uses a completely non-contact system based on structured light plethysmography (SLP) has recently been designed by Cambridge University Hospitals Foundation Trust. The device has been refined with the development of the Thora-3Di by Pneumacare Ltd, Cambridge. A grid of visible light is projected onto the thoraco-abdominal wall and two digital video cameras record changes in the grid pattern due to breathing motion. A waveform is produced by the anterior excursion of the thoraco-abdominal wall (SLPVol) over time, and a numerical output of RR is provided . The present study aims to simultaneously measure tidal breathing with the Thora-3Di and a BCI Capnograph 9004 device to compare the Thora-3Di RR output against that of the gold standard clinician over-scored end-tidal C02 (COSC) and to assess equivalence of the two devices with the aim to establishing the validity of SLP for RR measurement.

Conditions

• Pulmonary Disease

Interventions

DEVICE

Structured Light Plethysmography (Thora-3Di)

Respiratory Rate measured by Structured Light Plethysmography Thora-3Di and Clinician Over-scored End Tidal C02 (COSC) during 1 randomised minute of a 5 minute measurement period

DEVICE

BCI Capnograph 9004 (Smiths Medical)

Respiratory Rate measured by Structured Light Plethysmography Thora-3Di and Clinician Over-scored End Tidal C02 (COSC) during 1 randomised minute of a 5 minute measurement period

Sponsors & Collaborators

• Cambridge University Hospitals NHS Foundation Trust

  collaborator OTHER

• University of Cambridge

  collaborator OTHER

• Norfolk and Suffolk Primary and Community Care

  collaborator UNKNOWN

• Cambridge Clinical Research Ltd

  collaborator OTHER

• Kelly Statistical Consulting

  collaborator OTHER

• Pneumacare Ltd

  lead INDUSTRY

Principal Investigators

• Richard Iles, MD · Cambridge University Hospitals Foundation Trust

Study Design

Allocation

NA

Purpose

SUPPORTIVE_CARE

Masking

SINGLE

Model

SINGLE_GROUP

Eligibility

Min Age

18 Years

Max Age

80 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2015-02-28

Primary Completion

2015-05-31

Completion

2015-05-31

Countries

• United Kingdom

Study Locations