Correlates of thenar near-infrared spectroscopy-derived tissue O2 saturation after cardiac surgery.

We studied the significance of near-infrared spectroscopy (NIRS), for measuring tissue oxygenation (S(t)O(2)) and perfusion adequacy, and thus for haemodynamic monitoring of patients after cardiac surgery. We compared NIRS-derived S(t)O(2) of the thenar muscle to haemodynamic variables, oxygenation indices, temperature, lactate levels and urinary output, in 23 patients in the course of time after cardiac surgery and admission into the intensive care unit. Clinical variables, global haemodynamics and NIRS% total haemoglobin (%HT) and S(t)O(2) in the thenar for up to 18-22 h after admission were measured.