A fibre optic oxygen sensor that detects rapid PO₂ changes under simulated conditions of cyclical atelectasis in vitro

Journal article

Two challenges in the management of Acute Respiratory Distress Syndrome are the difficulty in diagnosing cyclical atelectasis, and in individualising mechanical ventilation therapy in real-time. Commercial optical oxygen sensors can detect P_aO2 oscillations associated with cyclical atelectasis, but are not accurate at saturation levels below 90%, and contain a toxic fluorophore. We present a computer-controlled test rig, together with an in-house constructed ultra-rapid sensor to test the limitations of these sensors when exposed to rapidly changing P_O2 in blood in vitro. We tested the sensors' responses to simulated respiratory rates between 10 and 60 breaths per minute. Our sensor was able to detect the whole amplitude of the imposed P_O2 oscillations, even at the highest respiratory rate. We also examined our sensor's resistance to clot formation by continuous in vivo deployment in non-heparinised flowing animal blood for 24 h, after which no adsorption of organic material on the sensor's surface was detectable by scanning electron microscopy.

Authors: Formenti, F; Chen, R; McPeak, H; Matejovic, M; Farmery, A

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Elsevier
• Journal: Respiratory physiology and neurobiology
• Volume: 191
• Issue: 1
• Pages: 1-8
• Publication date: 2014-01-01
• DOI: 10.1016/j.resp.2013.10.006
• EISSN: 1878-1519
• ISSN: 1569-9048
• Language: English
• Keywords: Microscopy, Electron, Scanning; Biological Clocks; Analysis of Variance; Fiber Optic Technology; Blood Pressure; Animals; Computer Simulation; Blood Coagulation; Pulmonary Atelectasis; Oxygen; Partial Pressure