Heart Surgery on the heart-lung machine involves, inter alia, by ischemia and reperfusion,
the release of reactive oxygen radicals and nitrogen oxide (NO), which damage DNA after
reaction with peroxynitrite, and Lipid-/Endothelmembrane Protein. The formation and
consumption of peroxynitrite can be reduced by intake of sodium selenite and the subsequent
formation of selenoprotein P. Since there is no storage for selenium, but the synthesis of
selenium-dependent enzymes is regulated by selenium resorption, the supplementation of
selenium is a potentially useful application in patients undergoing cardiac surgery.
After induction of anaesthesia and before connecting to the heart-lung machine the patients
get applied 2000μg sodium selenite (Selenase® T pro injection) intravenously (as a bolus
infusion over 30 minutes).
Furthermore, they get infused 1000μg sodium-selenite on each ICU-treatment day (also about 30
minutes). In addition, various blood values are recorded daily (including selenium levels)
within the routine blood samples. As the collection of these parameters is necessary anyway,
it constitutes no additional burden on the patient. Shortly before the transfer to general
ward there will be a final clinical examination.
In case of selenium level of 170μg per liter whole blood the employee of the laboratory
immediately informs the investigator by fax and requests a new blood sample for control
purposes (reference value for selenium in whole blood according to product information
100-144µg/ l). As long as the selenium level of the second sample is not higher than 230μg
selenium per liter whole blood, there are no further precautions necessary according to the
manufacturer`s recommendations. In case of selenium level above 230μg /l, the investigator
will be informed by fax without delay and the donation of investigational product will be
interrupted immediately. If a patient shows clinical signs of selenium toxicity (garlic-like
breath odor, fatigue, nausea, diarrhea, abdominal pain) it occurs an immediate termination of
the selenium dose, initiating symptomatic counteractive measures and further control samples.
All blood samples are taken by vascular catheters, which are already set for surgery or for
intensive care treatment, independent of the observational study.
