Figure 4.

Clinical instrumentation based on planar optical sensors for oxygen. A: Bypass system to monitor oxygen (and pH and CO₂) in blood that is guided through an extracorporeal system during cardiac surgery (© Terumo; www.terumo-cvs.com/). The cassette with blue ports shown at the bottom left is connected to the extracorporeal blood loop during a bypass operation, for example. It contains sensors for oxygen (and pH and CO₂) and is optically interrogated by the instrument via fiber optic cables. B: Disposable microfluidic chip (six sensor spots in total) to determine O₂ (and pH, CO₂, Na⁺, K⁺, and chloride or glucose) in an up to 120‐μL blood sample. The disposable chip is placed under the lid of a portable analyzer (C) called OPTI® R Blood Gas and Electrolyte Analyzer (OptiMedical; www.optimedical.com/).