Search results for "Cerebral oxygen"
showing 9 items of 9 documents
Cerebral oxygen saturation and cardiac output during anaesthesia in sitting position for neurosurgical procedures: a prospective observational study.
2016
Abstract Background Neurosurgical operations in the dorsal cranium often require the patient to be positioned in a sitting position. This can be associated with decreased cardiac output and cerebral hypoperfusion, and possibly, inadequate cerebral oxygenation. In the present study, cerebral oxygen saturation was measured during neurosurgery in the sitting position and correlated with cardiac output. Methods Perioperative cerebral oxygen saturation was measured continuously with two different monitors, INVOS® and FORE-SIGHT®. Cardiac output was measured at eight predefined time points using transoesophageal echocardiography. Results Forty patients were enrolled, but only 35 (20 female) were …
Human cerebral microcirculation and oxygen saturation during propofol-induced reduction of bispectral index †
2011
† This study investigates the effects of propofol-induced changes in bispectral index (BIS) on cerebral microcirculation and oxygenation during craniotomies. † In 2 mm cerebral depth, an increase in propofol dosage resulted in increased oxygen saturation (srvO2 )w ithout reduction of capillary venous blood flow (rvCBF). † Difference in oxygen content (avDO2) and approximated cerebralmetabolicrateofoxygen (aCMRO2) decreased with an increase in propofol dosage in 2 mm cerebral depth. † Alterations in BIS showed no effect on rvCBF, srvO2 ,a nd haemoglobin amount (rvHb) or on avDO2 or aCMRO2 in 8 mm cerebral depth. † These findings suggest that the CBF/CMRO2 ratio is altered by propofol in a re…
Influence of Beach Chair Position on Cerebral Oxygen Saturation
2013
Although beach chair position (BCP) is frequently used for shoulder surgery, a potentially detrimental influence on cerebral oxygenation is discussed. Therefore, the present study investigated changes in regional cerebral oxygen saturation (rSO2/StO2) during BCP comparing 2 different devices for near-infrared spectroscopy measurement.Data were collected in 35 patients undergoing shoulder surgery in BCP and compared with a control group of 35 awake volunteers. The rSO2/StO2 was assessed using INVOS and FORE-SIGHT monitors. Mean arterial blood pressure (MAP), peripheral oxygen saturation (SpO2), PeCO2, FiO2, end-tidal sevoflurane concentration, and rSO2/StO2 were measured before positioning, …
Changes in cerebral oxygen saturation following prone positioning for orthopaedic surgery under general anaesthesia: a prospective observational stud…
2015
Prone positioning is often necessary in orthopaedic surgery. The prone position, however, may result in impaired cerebral venous drainage with a subsequent reduction in cerebral perfusion. As a consequence, cerebral hypoxia may occur with the potential for neurological impairment.We assessed the changes in cerebral oxygen saturation with near-infrared spectroscopy using two different monitors after positioning the patient from supine to prone.Prospective observational study.Primary Care University Hospital, from May 2010 to February 2011.Forty patients undergoing general anaesthetic procedures, of which 35 completed the investigation. Similar measurements were done in 35 volunteers, who wer…
Cerebral Oxygen Supply in Brain Edema and During Ventriculo-Cisternal Perfusion
1976
Numerous brain injuries and brain tumors lead to edema in brain tissue which can have consequences for the oxygen supply to the damaged tissue as well as to adjacent tissue areas. In studies made of the blood flow and oxygen supply in perifocal edematous tissue of brain tumors and lesions in patients undergoing various brain operations a direct relationship between the regional blood flow and the water content could be demonstrated (3). As the water content of the tissue increased, the blood flow through it diminished. In many cases, the reduction of the blood flow in the brain tissue induced an insufficient oxygen supply. In the tissue samples under investigation, the CrP and ATP concentra…
The Influence of Oxygen Affinity of Blood and Cerebral Blood Flow on Cerebral Oxygen Supply
1969
The quantity of oxygen transported, per unit of time, by the blood to the brain, is determined by the blood flow, the oxygen capacity, and the oxygen affinity of the blood. The O2-exchange between the blood and the tissue cells depends mainly on the oxygen transport characteristics of the blood and the O2 diffusion conditions in the blood and tissue.
Peripheral Intravenous Access in Preterm Neonates during Postnatal Stabilization: Feasibility and Safety
2017
Background Current European Guideline for resuscitation recommends a centrally positioned umbilical venous catheter as the best option for administering necessary drugs. Especially in preterm infants, a frequently used alternative is the peripheral venous catheter. Methods Two randomized controlled studies were conducted at the Division of Neonatology, Medical University of Graz. During neonatal resuscitation, a standardized protocol was filled out by an uninvolved observer including time points after birth of all attempts of venous puncture, time point of successful venous puncture, and total number of needed attempts. Arterial oxygen saturation (SpO2) and heart rate (HR) were measured usi…
Lung Injury Is a Predictor of Cerebral Hypoxia and Mortality in Traumatic Brain Injury
2020
Background: A major contributor to unfavorable outcome after traumatic brain injury (TBI) is secondary brain injury. Low brain tissue oxygen tension (PbtO2) has shown to be an independent predictor of unfavorable outcome. Although PbtO2 provides clinicians with an understanding of the ischemic and non-ischemic derangements of brain physiology, its value does not take into consideration systemic oxygenation that can influence patients' outcomes. This study analyses brain and systemic oxygenation and a number of related indices in TBI patients: PbtO2, partial arterial oxygenation pressure (PaO2), PbtO2/PaO2, ratio of PbtO2 to fraction of inspired oxygen (FiO2), and PaO2/FiO2. The primary aim …
Intensive Care Management of Head-Injured Patient
2019
Traumatic brain injury (TBI) plays an important role for the prognosis of multiple injured patients. Severely injured patients require intensive care treatment to support organ function and to maintain normal brain physiology. Optimal treatment is a cornerstone for good outcome. Therefore, in addition to general principles and concepts of modern intensive care medicine, special brain-specific aspects need to be addressed in these patients. Essential aspects of physiological regulation of cerebral perfusion and intracranial pressure as well as recent publications are reviewed as basis for current trends in the management of TBI patients. Focusing on single parameters such as intracranial pre…