Introduction. Cerebral infarction is more and more frequently present by massive participation and high percentage of mortality even in young population. It is notified as very hard, vitally endangered disease. Objective. To prove whether there is a difference in the gas analyses of the arterial and cerebral venous blood between the patients with the cerebral infarction of the left and right hemisphere and why it is significant for the treatment of those patients. Material and methods. Sixty-five (65) patients of both sexes who were diagnosed by CT as: cerebral infarction, cerebral multiinfarctions and cerebral haemorrhagic infarctions were investigated. Under the same conditions their radial artery and left and right internal jugular vein were tapped - on the fourth, eighth and tenth day of their disease. Gas analysis, calculation of oxygen content and statistical comparison of testing results were performed from the samples of arterial and venous blood. Results. By continuous monitoring of gas analysis parameters of arterial and cerebral venous blood from internal jugular vein, we can follow up the phases of disease, the velocity of changes of gas analysis parameters and adequacy of brain circulation and to correct therapy adequately for the purpose of preventing basic disease complications and to estimate the results of treatment. Conclusion. There is a significant difference between the results of gas analysis of arteries and the internal jugular vein, in patients with infarctions of the left and right hemisphere of the brain.Uvod. Infarkti mozga su sve češće zastupljeni i kod mlađe populacije. Praćeni su visokim procentom mortaliteta. Zato ih svrstavamo u teška, vitalno ugrožavajuća oboljenja. Cilj rada. Dokazati da li postoji terapijski značajna razlika u gasnim analizama arterijske i venske krvi (unutrašnje jugularne vene), kod infarkta leve i desne hemisfere mozga. Metod rada. Ispitivano je 65 bolesnika, oba pola, koji su imali dijagnozu verifikovanu kompjuterizovanom tomografijom (CT): infarkt, multiinfarkti i hemoragijski infarkti mozga. Pod jednakim uslovima punktirane su im: arteria radialis, leva i desna unutrašnja jugularna vena - četvrtog, osmog i desetog dana bolesti. Iz uzoraka arterijske i venske krvi rađene su gasne analize i izračunavan sadržaj kiseonika. Rezultati su međusobno upoređivani i obrađivani odgovarajućim statističkim metodama. Rezultati. Kontinuiranim praćenjem parametara gasnih analiza arterijske i venske krvi (unutrašnje jugularne vene) uočene su različite faze bolesti, brzina promene parametara gasnih analiza, stepen adekvatnosti moždane cirkulacije - to sve pomaže u korigovanju terapije, prevenciji komplikacija osnovne bolesti i procenjivanju ishoda lečenja. Zaključak. U gasnim analizama arterija i unutrašnje jugularne vene kod bolesnika sa infarktom leve i desne hemisfere mozga postoji značajna razlika