Several studies have pointed to the potential advantages of SctO2 monitoring in the peri-operative phase after cardiac or abdominal surgery in adults [1,2,3,4], as well as in children undergoing surgical corrections of congenital cardiac defects [5,6,7]. Low SctO2 values are associated with worse outcome, and correspond with data from other monitors indicating that the oxygen content of the brain at that time is insufficient. In particular, the duration of SctO2 desaturations below 55%, 60%, and 65%, is predictive for postoperative complications [8]. These studies, however, have only analyzed the use of NIRS as a tool to monitor the brain at times when it is at the highest risk, during complex surgery with a compromised circulation. Although there is no evidence that has demonstrated that decision making based on NIRS data is favorable for patient outcome, many centers use NIRS as a monitoring tool outside of the surgical environment.