Chapter 4 - The Oxygen Reserve Index

Pulse oximetry was one of the most quickly and widely adopted bedside monitors in the operating room and intensive care unit. Improvements to it over time have increased its reliability and extended its applications. Advanced warning of critical oxygen desaturation, especially during airway management, is a goal of a new pulse oximetry function termed “oxygen reserve index.” This function in its current state of development would alarm when the SpO2 is> 99% and predict the decrease to an SpO2 < 98% in a time frame (e.g., 30--40 seconds) that might impact management. This chapter reviews this function, the clinical investigations published thus far, and the possible benefits and difficulties in utilizing such an alarm.