The nurse practitioner is rounding in the intensive care uni…

The nurse practitioner is rounding in the intensive care unit. A nurse stops the practitioner to discuss some results on a patient and to get further recommendations for care. The patient was admitted for hypotension, acute anemia with on going blood loss secondary to a GI bleed. The patient was on warfarin for history of Protein S Deficiency and it is now on hold. The patient is intubated though vital signs have normalized. The patient is more obtunded off of sedation today. The patient has a pulmonary artery catheter and a SvO2 (mixed venous o2 saturation). The results are 55% (Normal is 60-80%). What is the likely cause?