Cerebrоvаsсulаr Resistance in Patients with Severe Combined Traumatic Stresspoints Brain Injury

PROBLEMS OF NEUROSURGERY NAMED AFTER N.N. BURDENKO 5, 2015 One of the key aspects of any effective brain injury treatment is to maintain the optimal levels of cerebral perfusion and oxygenation [1, 2]. There are different ways to define of this optimum, including simultaneous use of modern techniques of assessment of cerebral macroand microcirculation (for example, using Doppler sonography or laser studies simultaneously with perfusion X-ray or magnetic resonance tomography) with subsequent calculation of derivative indices and values [3—7]. This approach allows non-invasive assessment of the immediate state of cerebral microvasculature [8—10], high degree of accuracy in calculation of cerebral hemodynamics indicators, in particular cerebral perfusion pressure [11, 12], as well as determination of “secondary”, derivative, parameters reflecting the condition cerebral microvasculature. One of the parameters is сerebrоvаsсulаr resistance (CVR) [13—15]. It has been demonstrated that сerebrоvаsсulаr resistance (CVR) ensures constancy of the cerebral perfusion in case of spontaneous or induced changes in hydrostatic and systemic arterial blood pressure and prevents the development vasogenic edema [16, 17]. It has been noted that such effect of сerebrоvаsсulаr resistance is achieved at an average arterial blood pressure of 40 to 140 mmHg, i.e. in the same interval in which the mechanisms of cerebral blood flow autoregulation operate. It demonstrates clear relationships between mechanisms of cerebral blood flow autoregulation and CVR maintenance [18]. CVR acts through changes in smooth muscle tone of the entire bloodstream. This process involves primarily precapillary