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Questions and Answers
What does a reduction in SvO2 typically indicate?
What does a reduction in SvO2 typically indicate?
In which conditions is DO2 most likely to decrease?
In which conditions is DO2 most likely to decrease?
What could an increase in VO2 indicate?
What could an increase in VO2 indicate?
What could an increase in SvO2 indicate?
What could an increase in SvO2 indicate?
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What effect does a small increase in FIO2 have on SvO2 at typical PO2 values in venous blood?
What effect does a small increase in FIO2 have on SvO2 at typical PO2 values in venous blood?
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In the setting of septic shock, despite the presence of tissue hypoxia, what may SvO2 values indicate?
In the setting of septic shock, despite the presence of tissue hypoxia, what may SvO2 values indicate?
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What can be used as a surrogate for direct measurement of SvO2?
What can be used as a surrogate for direct measurement of SvO2?
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In normal physiologic conditions, what is the usual difference between SCVO2 and SvO2?
In normal physiologic conditions, what is the usual difference between SCVO2 and SvO2?
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What causes the primary difference between SCVO2 and SvO2?
What causes the primary difference between SCVO2 and SvO2?
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What can be computed using mixed venous CO2 according to the text?
What can be computed using mixed venous CO2 according to the text?
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During hemodynamic instability, how may the relationship between SvO2 and SCVO2 change?
During hemodynamic instability, how may the relationship between SvO2 and SCVO2 change?
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What does the saturation of blood at the proximal pulmonary artery reflect?
What does the saturation of blood at the proximal pulmonary artery reflect?
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What does SvO2 reflect in relation to oxygen?
What does SvO2 reflect in relation to oxygen?
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How can SCVO2 placed in the superior vena cava be characterized in terms of oxygen supply and demand?
How can SCVO2 placed in the superior vena cava be characterized in terms of oxygen supply and demand?
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What can cause falsely increased values in venous O2 saturation measurements?
What can cause falsely increased values in venous O2 saturation measurements?
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What is an advantage of using specialized venous oximetry catheters for O2 saturation monitoring?
What is an advantage of using specialized venous oximetry catheters for O2 saturation monitoring?
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What is a disadvantage of specialized venous oximetry catheters for O2 saturation monitoring?
What is a disadvantage of specialized venous oximetry catheters for O2 saturation monitoring?
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What have protocol-based interventions targeting specific values of SvO2 or SCVO2 been shown to reduce in patients undergoing major surgery and patients present with sepsis?
What have protocol-based interventions targeting specific values of SvO2 or SCVO2 been shown to reduce in patients undergoing major surgery and patients present with sepsis?
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How do other measures like lactate clearance compare to SCVO2 as endpoints in sepsis management?
How do other measures like lactate clearance compare to SCVO2 as endpoints in sepsis management?
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Goal- directed therapy based on ScvO2 has been advocated for the management of ?
Goal- directed therapy based on ScvO2 has been advocated for the management of ?
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What is a potential marker of complications after cardiac surgery according to the text?
What is a potential marker of complications after cardiac surgery according to the text?
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Why does ScvO2 may be increased in sepsis according to the text?
Why does ScvO2 may be increased in sepsis according to the text?
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What does regional oxygen balance refer to?
What does regional oxygen balance refer to?
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How does reflectance spectroscopy assess microcirculatory oxygenation?
How does reflectance spectroscopy assess microcirculatory oxygenation?
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How does light transmission through tissue in reflectance spectroscopy get affected?
How does light transmission through tissue in reflectance spectroscopy get affected?
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What does the Beer-Lambert law relate the absorption of light by tissue to?
What does the Beer-Lambert law relate the absorption of light by tissue to?
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Which of the following is the predominant tissue chromophore that affects light absorption?
Which of the following is the predominant tissue chromophore that affects light absorption?
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What does a SvO2 value of 40% indicate?
What does a SvO2 value of 40% indicate?
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How can PvO2 be derived from SvO2 values?
How can PvO2 be derived from SvO2 values?
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What is the normal value of PvO2?
What is the normal value of PvO2?
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How is DO2 defined?
How is DO2 defined?
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What is the normal values of SvO2?
What is the normal values of SvO2?
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O2 extraction ratio, ERO2 formula expressed as ?
O2 extraction ratio, ERO2 formula expressed as ?
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in which of the following cases SvO2 readings ca reflect normal values despite the presence of tissue hypoxia?
in which of the following cases SvO2 readings ca reflect normal values despite the presence of tissue hypoxia?
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Current noninvasive methods for the assessment of microcirculatory oxygenation use of reflectance spectroscopy using light either in ?
Current noninvasive methods for the assessment of microcirculatory oxygenation use of reflectance spectroscopy using light either in ?
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What characteristic of VLS makes it suitable for measurements of small subsurface volumes compared to NIRS?
What characteristic of VLS makes it suitable for measurements of small subsurface volumes compared to NIRS?
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Which statement best describes the depth of penetration of light in NIRS compared to VLS according to the text?
Which statement best describes the depth of penetration of light in NIRS compared to VLS according to the text?
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What volume is included in the O2 saturation displayed by using VLS or NIRS?
What volume is included in the O2 saturation displayed by using VLS or NIRS?
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What type of measurements are VLS suitable for primarily based on its depth of penetration?
What type of measurements are VLS suitable for primarily based on its depth of penetration?
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What distinguishes the depth of tissue penetration between NIRS and VLS in terms of measurement capabilities?
What distinguishes the depth of tissue penetration between NIRS and VLS in terms of measurement capabilities?
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VLS use ?
VLS use ?
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NIRS use light with wavelengths of?
NIRS use light with wavelengths of?
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Which surgical procedure can benefit from the use of VLS ?
Which surgical procedure can benefit from the use of VLS ?
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What is the suggested threshold for intervention based on reduction of rSO2 during cerebral oximetry?
What is the suggested threshold for intervention based on reduction of rSO2 during cerebral oximetry?
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What is the range of typical values for rSO2 during cerebral oximetry?
What is the range of typical values for rSO2 during cerebral oximetry?
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What is the primary application of NIRS as mentioned in the text?
What is the primary application of NIRS as mentioned in the text?
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What does a reduction in gastrointestinal tissue saturation, measured by VLS, suggest according to the text?
What does a reduction in gastrointestinal tissue saturation, measured by VLS, suggest according to the text?
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In patients undergoing coronary artery bypass graft surgery,at what percentage interventions for rSO2 reductions from baseline has been shown to significantly reduce morbidity and mortality?
In patients undergoing coronary artery bypass graft surgery,at what percentage interventions for rSO2 reductions from baseline has been shown to significantly reduce morbidity and mortality?
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For carotid endarterectomy, what rSO2 reduction threshold of baseline are well tolerated?
For carotid endarterectomy, what rSO2 reduction threshold of baseline are well tolerated?
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In elderly patients undergoing major abdominal surgery, protocol-based intraoperative treatment of reductions in rSO2 results in ?
In elderly patients undergoing major abdominal surgery, protocol-based intraoperative treatment of reductions in rSO2 results in ?
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During single-lung ventilation in thoracic surgical procedures, cognitive dysfunction has been linked to exposure time with rSO2 less than what value?
During single-lung ventilation in thoracic surgical procedures, cognitive dysfunction has been linked to exposure time with rSO2 less than what value?
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In major trauma patients presenting with shock, what can StO2 values potentially help identify?
In major trauma patients presenting with shock, what can StO2 values potentially help identify?
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What is the recommended threshold for intervention based on reduction of rSO2 during cerebral oximetry?
What is the recommended threshold for intervention based on reduction of rSO2 during cerebral oximetry?
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Why is it challenging to compare the accuracy of different NIRS systems?
Why is it challenging to compare the accuracy of different NIRS systems?
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What is the baseline mean rSO2 value recommended to be acquired for each patient at the start of a procedure?
What is the baseline mean rSO2 value recommended to be acquired for each patient at the start of a procedure?
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What is recommended for the using of NIRS devices?
What is recommended for the using of NIRS devices?
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