Background: The level of arterial carbon dioxide partial tension (PaCO2) is a sine qua non for the determination of the adequacy of ventilation. The aim of this study was to assess the usefulness of SenTec Digital Monitor System in measuring transcutaneous arterial carbon dioxide partial tension (PCO2) non-invasively for the management of chronic respiratory failure.
Methods: Three ICU patients suffering from chronic respiratory failure were enrolled. We recorded the data of PCO2 measured by a transcutaneous ear sensor (V-Sign : SenTec Inc.) and the data of PaCO2 (GASTAT-603ie Techno Medica Co., Ltd., Japan) obtained from arterial blood gas analysis.
Results: The mean PCO2 was 67.2 mmHg (min. 65.9 mmHg, max. 80.2 mmHg, n = 10), and the mean PaCO2 was 71.2 mmHg (min. 67.2 mmHg, max. 79.0 mmHg, n = 10). Regression analysis showed good correlation between PCO2 and PaCO2 (PCO2 = .95 x PaCO2-0.18 mmHg; R = 0.74). Bland-Altman analysis of PCO2 yields a bias of d = 3.9 mmHg with limits of agreement (1SD) -0.4 mmHg, +8.2 mmHg.
Conclusions: SenTec Digital Monitor System enables non-invasive and reliable trend monitoring of PCO2 levels in patients with chronic respiratory failure.