Retrograde catheterization of the internal jugular venous bulb is a useful technique which is becoming more widespread as it enables monitoring of cerebral blood flow and cerebral metabolism. In this study, we aimed to determine our neuroanaesthesia as an objective technique. After Ethic Committee approval, 10 patients with head trauma were included in this study. Radial arter and jugular venous cannulation were performed in operating room. Blood gases, Hb, osmolality, BUN, Na, and K were analysed. Patients were anesthetized with thiopental, atracurium, fentanyl and isoflurane. We performed normoventilation using 50 % O2-air mixture. Simultaneous arterial andjugular venous gases were obtained after skin incision, when dura opened and when dura closed. pH, pCO2, HCO3, SO2 and CntO2 values were recorded. Severe desaturation was detected in all patients. They had low arterial pCO2. Cerebral venous desaturation was corrected at higher levels of inspired O2, with mannitol and by increasing arteryel PCO2 2-3 mmHg when SjO2 below 50 %. Arteriovenous differences in pCO2, pH, and CntO2 were evaluated. All these parameters tended to decrease towards the end of the operation. These results indicated that cerebral perfusion was improved by adaptation of ventilation, osmotherapy and surgical decompression. We concluded that intraoperative monitoring of SjO2 may be beneficial in patients undergoing neurosurgical procedures. [Journal of Turgut Özal Medical Center 1997;4(3):294-297]
Key Words: Cerebral perfusion, jugular bulb, blood gas
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