Mesure de l’oxygénation des tissus par spectroscopie proche infrarouge chez des patients sous hémodialyse

Using this method, we can understand oxygen dynamics of organ during hemodialysis. Prior to the development of this protocol, we could not confirm changes in regional oxygen of each organ. This simple technique can evaluate regional oxygen saturation, non-invasive and in real-time.

In dialysis patients, such monitoring might detect intradyalitic hypertension or length ischemia dry during HD.This neuro system has been used in several areas. Cardiovascular and cerebrovascular surgery, neonatal, intensive care, and prehospital emergency. We hope this monitoring will be used in other areas in the future.

For example, diagnosis of cognitive impairment. Begin by preparing a near-infrared spectroscopy or NIRS device for measuring tissue oxygenation. This device has four channels and can perform measurement in up to four organs at the same time.

In addition, prepare measurement sensors for NIRS monitoring to evaluate regional oxygen saturation values in each organ, by a transmitting near-infrared light at two wavelengths of attachment. Allow the patient to rest in a supine position for at least five minutes before hemodialysis. Then attach measurement sensors to the forehead, the right hypochondrium and lower legs to evaluate regional oxygen saturation in the brain, liver, and lower leg muscles, respectively.

For cerebral regional oxygen saturation measurement, attach the sensors to the forehead of the dominant hemisphere. For hepatic measurements, measure the depth of the patient's liver from the body surface, and confirm that this measurement is within 20 to 30 millimeters. Next, attach the measurement sensors to the right hypochondrium.

To monitor muscle oxygenation, attach measurement sensors to the right or bilateral lower legs. Connect each sensor to the leads from the device. Then, turn on the device and start measuring oxygenation.

Puncture the patient's dialysis shunt to start hemodialysis therapy. Measure blood pressure using a digital blood pressure monitor equipped with the dialysis machine, and collect blood samples using syringes. After starting therapy, start monitoring the tissue oxygenation of the three organs.

In addition to the usual monitoring performed during hemodialysis, observe changes in regional oxygen saturation values of each organ and measure blood pressure regularly. Confirm the attachment area and connection between the sensors and leads. Cerebral oxygen saturation values of hemodialysis patients before hemodialysis were lower than those of healthy subjects.

The saturation values of hemodialysis patients with diabetes mellitus were lower than those in hemodialysis patients without diabetes. Although tissue oxygenation continues without a decrease of blood pressure during hemodialysis, changes in cerebral and hepatic regional oxygen saturation due to intradyalitic hypotension were observed. When attempting this protocol, it is important to compound the location measurement sensors and to apply the sensors'registry.

The new system itself is not a new technique. However, the application of this monitoring system to hemodialysis is another and it is very useful to evaluate changes in organ oxygenation during hemodialysis.