WHAT IS INVOLVED: Randomization of 50 patients is balanced by experimental group; control and intervention, with an allocation sequence based on a block size of ten, generated with a computer random number generator. In the INTERVENTION group ICU Staff will use NIRS to follow a physiologically guided strategy to maintain rSO2 within 90% of baseline values. In the CONTROL group ICU Staff will provide standard of care without the use of NIRS.