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The authors studied the time course of changes in the parameters of the cerebral thyronergic system (total and free triiodthyronine (T3) and thyroxin (T4), thyroxine-binding globulin (TBG), thyroid-stimulating hormone (TSH) by radioimmunoassay (Immunotech, Czechia; CIS, France), proinflammatory cytokine of TNF-alpha by enzyme immunoassay (Innogenetic, Belgium) in the blood and cerebrospinal fluid (CSF) in 59 patients (37 males and 22 females whose age ranged from 21 to 64 years) in acute subarachnoidal hemorrhage due to arterial aneurysmal rupture. On admission, the condition of 47 (79.7%) was rated as grades III-VI according to the Hunt-Hess scale, which was responsible for high mortality rates (33.89% in the assessment of outcomes according to the Glasgow outcome scale). The causes of death were ischemic and hemorrhagic insults, edema of the brain, cerebral stem wedging. Laboratory findings were analyzed in relation to the clinical condition of patients, outcomes, and the degree of secondary vasospasm assessed by Doppler transcranial study by the average blood flow velocity in the middle cerebral artery. They revealed a significant depression of thyroidal metabolism with developed the total low T3 syndrome just before surgical treatment in patients with deterioration in the early postoperative period. The significant correlations found by the authors between the decreased blood T3 and TSH levels and 1) the severity of neurological disorders; 2) the degree of vasospasm, and 3) the outcome of disease, as well as negative correlations of elevated TNF-alpha levels not only in the blood, but also in CSF with the content of CT3, CT4 and with the severity of neurological symptomatology are indicative of the development of isolated syndrome in the brain, which is characterized by specific thyroidal metabolic disorders, which the author propose to call the cerebral low T3 syndrome (by taking into account the presence of the autonomic systems of thyroidal homeostatic provision).

The authors discuss the results of pharmacological protection of the brain, consisting in intraarterial or intravenous infusion of drugs (sodium thiopental, nimodipine, ketamine) during intracranial interventions in 13 patients with giant arterial aneurysms of the anterior portions of Willis' circle. In some patients drug protection of the brain prevented the development of ischemic focus in the basin of temporarily occluded vessel. Intraarterial infusion of protector drugs is preferable because it allows decreasing the doses and severity of untoward hemodynamic effects.

The relationship between lipid peroxidation products and the severity of arterial spasm was studied in 86 patients. For this, the level of radical production, the content of the end lipid peroxidation product malonic dialdehyde and the overall antioxidative activity of lumbar cerebrospinal fluid were determined during 24-hour Doppler monitoring of blood flow in the middle cerebral and internal carotid arteries. Following subarachnoidal hemorrhage, the activation of lipid peroxidation processes was shown to correlate with the severity of arterial spasm and it is likely to contribute to the development of late ischemias. Nimotop used to treat patients with significant arterial spasm caused a reduction in the rate of free radical lipid peroxidation to that characteristic for patients with moderate spasm. The findings suggest that it is expedient of including antioxidants into the combined therapy of patients with acute subarachnoidal hemorrhage.

Changes in intracranial pressure (ICP) and cerebral circulation were evaluated from Doppler transcranial ultrasound (DTU) in 29 patients with spontaneous aneurysmal hemorrhage in acute rupture. There is a tendency for the pulse wave amplitude (PWA) of ICP to increase concurrently with higher ICP values (r = 0.768, p < 0.01), the tendency being smoother in patients with severe diffuse spasm (r = 0.573, p < 0.01). There was also a linear correlation between the ICP values and the pulse index of blood flow velocity (r = 0.783, p < 0.01). Evidence is given for the possibility of indirect assessment of ICP from DTU data and for that of indirect evaluation of cerebral perfusion from ICP monitoring data. In the latter case, the authors used a ICP PWA ratio. The findings suggest that the decrease in PWA/ICP values by less than 0.2 during intracranial hypertension and severe diffuse arterial spasm corresponds to the reduction in cerebral blood filling beyond the critical values.

The clinical status, angiographic and Doppler ultrasound transcranial findings were compared in 50 patients with acute subarachnoidal hemorrhage (40 with aneurysmal hemorrhage and 10 with unknown hemorrhage). There was a correlation between the change in the linear velocity of blood flow in the cerebral arteries and the clinical manifestations of arterial spasm-induced brain ischemia. With this, Doppler signs of arterial spasm appeared as clinical manifestations 3-4 days earlier. The linear velocity of middle cerebral arterial blood flow, which is critical for the development of ischemic complications of arterial spasm was 295 +/- 6 cm/sec. The magnitude and duration of the excess critical level of the linear velocity of blood flow and the presence of arterial spasm in the contralateral hemisphere may determine whether the progressive ischemic symptoms are reversible or irreversible. A further course of arterial spasm, development of ischemic complications and their outcomes may be predicted by the increasing gradient of the linear velocity in the cerebral arteries at days 4-6 of subarachnoidal hemorrhage and the extent of spasm.

The paper deals with the specific features of using Doppler transcranial sonography in patients with subarachnoid hemorrhage. It describes the advantages and disadvantages of the method for the diagnosis of arterial spasm of various intracranial arteries. A comparison of angiographic and Doppler sonographic findings revealed that the values of the peak systolic velocity of blood flow (r = -0.875, p < 0.0001) are the most informative for the diagnosis of the extent of intracranial arterial lumenal narrowing. Patients with aneurysm ruptures in the internal carotid and middle cerebral arteries were found to have a pronounced increase in the blood flow velocity at the site of aneurysm. The intracranial arterial blood flow parameters critical for the development of brain ischemia during cerebral arterial spasm after subarachnoid hemorrhage are specified in the paper.