In 56 patients aged from 58 to 82 years with the III and IV degrees of risk operated upon for malignant tumors of organs of the thoracic and abdominal organs Solcoseryl was included in the complex of anesthesia measures. It was given intravenously or as inhalation in dosage of 1000 mg. It was found that using Solcoseryl considerably reduced the amount of postoperative complications in high risk patients. It led to lower level of lipid peroxidation and activation of the antioxidant system and thus may be considered as an important component of therapy at the intra- and postoperative periods.