Fortiori Design LLC
Registered: 1355349061 Posts: 1,530
Here anoteh exampel fo teh fundemantl differetn use of NIRS by our group and teh classical school idea.
Monitoring skeletal muscle oxygenation during exercise by near infrared spectroscopy in chronic heart failure. Servizio di Cardiologia Riabilitativa, Istituto Lancisi, Ancona, Italy. Abstract
Patients with chronic heart failure (HF) have a reduced skeletal muscle blood flow which can in part explain reduced exercise tolerance and increased ventilation. All the techniques commonly employed to measure skeletal muscle blood flow have limitations that reduce their accuracy and clinical application. Near infrared spectroscopy (NIRS) is a noninvasive, inexpensive, and reproducible technique able to monitor muscle oxygenation both at rest and during exercise, providing information about tissue perfusion. The principle of NIRS is based on the observation that the light absorption characteristics of hemoglobin (Hb) and myoglobin (Mb) in the near infrared region (700-1000 nm) change depending on their relative saturations. In humans, NIRS has been employed to monitor skeletal muscle oxygenation during exercise and/or after cuff-induced limb ischemia in normal subjects as well as patients with chronic HF. Patients with chronic HF have a reduced Hb/Mb oxygenation at any matched work rate and a more rapid deoxygenation above the anaerobic threshold than normal subjects. More recently, NIRS has been used to determine the kinetics of muscle oxygenation in recovery after constant work rate exercise, providing evidence of an inverse relation with cardiac function as assessed by peak oxygen uptake. In conclusion, NIRS appears to be a new promising noninvasive technique for studying muscle oxygenation in a variety of experimental models. (c)1999 by CHF, Inc
blood flow have limitations that They often agree, that " blood flow' is one of the limitation. So cardiac problems have a feedback loop over blood flow as does respiration. . So by testing O2Hb and HHb we only get a feedback over utilization of O2 but not as mentioned over the potential limitation of delivery due to the cardiac limitation. So using ,as we do, a combination of tHb ( blood flow ) delivery information and SmO2 utilization information seems for us to make some sense ????