In the manual from modern positions, theoretical and practical issues of treatment of critical conditions in intensive care and resuscitation departments are considered. The causes, development and clinical manifestations of acute respiratory and cardiovascular failure, various types of shock, imbalance of water and electrolytes, violations of the acid-base condition, pain syndrome and coma. are analyzed. Methods of respiratory and cardiovascular support, correction of homeostasis shifts, infusion therapy, parenteral nutrition . are described in detail Algorithms of resuscitation measures for various forms of cardiac arrest, methods of first aid at the prehospital stage are given For doctors specializing in anesthesiology, resuscitation and intensive care, emergency physicians, surgeons, therapists.