Search results for "Oxygen Saturation Measurement"
showing 4 items of 4 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…
Closed-Loop Automatic Oxygen Control (CLAC) in Preterm Infants: A Randomized Controlled Trial
2014
BACKGROUND AND OBJECTIVE: In preterm infants receiving supplemental oxygen, routine manual control (RMC) of the fraction of inspired oxygen (FIO2) is often difficult and time consuming. We developed a system for closed-loop automatic control (CLAC) of the FIO2 and demonstrated its short-term safety and efficacy in a single-center study. The objective of this study was to test the hypothesis that this system is more effective than RMC alone in maintaining arterial oxygen saturation within target levels when evaluated over 24 hours under routine conditions and with different target levels. METHODS: We performed a multicenter, randomized controlled, crossover clinical trial in 34 preterm infa…
Transmission of arterial oxygen partial pressure oscillations to the cerebral microcirculation in a porcine model of acute lung injury caused by cycl…
2013
Cyclic recruitment and derecruitment (R/D) play a key role in the pathomechanism of acute lung injury (ALI) leading to respiration-dependent oscillations of arterial partial pressure of oxygen (Pa(O(2))). These Pa(O(2)) oscillations could also be forwarded to the cerebral microcirculation.In 12 pigs, partial pressure of oxygen was measured in the thoracic aorta (Pa(O(2))) and subcortical cerebral tissue (Pbr(O(2))). Cerebral cortical haemoglobin oxygen saturation (Sbr(O(2))), cerebral blood flow (CBF), and peripheral haemoglobin saturation (Sp(O(2))) were assessed by spectroscopy and laser Doppler flowmetry. Measurements at different fractions of inspired oxygen (F(I(O(2)))) were performed …