The clinical evaluation of the Respi-check mask: a new oxygen mask incorporating a breathing indicator

Study objective-To investigate the correlation between the Respi-check sensor and simultaneous chest auscultation in determining the respiratory rates in adults.

Random visits to a local accident and emergency (A&E) department were made and all patients wearing oxygen masks were recruited into the study. The new sensor was attached to the outside of the mask. One researcher auscultated the chest to count breaths, the other counted the sensor activity. Each was blinded to the activities of the other. Breaths were counted by each researcher simultaneously and independently over one minute. A total of 40 patients were recruited into the study. A difference of more than two breaths/min compared with chest auscultation was deemed as a sensor failure.

The respiratory rates of 40 patients were measured. There were 28 men, 12 women. Twenty six patients were wearing an Intersurgical high concentration (flow 12l/min) mask, 14 were wearing an aerosol mask with variable venturi (flow 3-12l/min) by Medicaid. Over one minute rates determined by the two methods were the same in 28 cases (70%). It was accurate to within one breath in 37 cases (93%) and to within two breaths in 39 (98%) cases and in one case (2.5%) the sensor failed. The mean difference (mean of the differences between rates obtained from auscultation and the new sensor) was -0.1282 breaths/min, with limits of agreement (d (2SD) between -1.414 to 1.157 breaths/min.

The Respi-check sensor provides an accurate method of estimating the respiratory rate in adult patients attending the A&E department.