Week 8 Cerebral Pulse Flashcards
What is Cerebral Oximetry?
Monitors for adequacy of brain oxygenation. It uses Near-Infrared Spectrometry (NIRS) and pads applied to the patient’s forehead with a light source that measures light attenuation.
What are the clinical indications for Cerebral Oximetry?
Cardiac surgery, carotid endarterectomy, neonates, provider’s preference, neuro intensive care patients / SAH sp coil.
What is the goal of Cerebral Oximetry during procedures?
Avoiding cerebral desaturation during these procedures is believed to reduce complications relating to cerebral ischemia.
How should readings be interpreted in Cerebral Oximetry?
Obtain the patient’s pre-induction baseline. No ‘abnormal’ level suggestive of cerebral ischemia. The goal is to maintain a value minimum of 75% of the baseline and set alarm limits to goal.
What are common causes of desaturation in Cerebral Oximetry?
Oxygen delivery is impaired, anemia, decreased arterial oxygen saturation, diminished cardiac output, vasospasm.
Which of the following modalities is used to monitor the level of oxygenation in the
brain?
A) Pulse oximetry
B) BIS monitoring
C) Cerebral oximetry
D) Cerebral capnometry
Answer: C) Cerebral oximetry
Cerebral oximetry. Monitoring for adequacy of oxygenation specific to the brain
Reference: Nagelhout, J. J., Elisha, S., & Heiner, J. S. (2023). Nurse Anesthesia (7th
What type of technology does the cerebral oximeter use?
A) Bispectral Index
B) Termal infrared imaging
C) Termal infrared sensing
D) Near-infrared spectroscopy
Answer: D) Near-infrared spectroscopy
Monitoring for adequacy of oxygenation specific to the brain has been demonstrated through the
use of near infrared spectroscopy (NIRS) in monitoring, which is referred to as cerebral
oximetry.
How does a cerebral oximeter function in monitoring brain oxygenation?
A) By measuring electrical activity of the brain through EEG signals
B) By detecting changes in blood pressure using arterial waveforms
C) By measuring light attenuation from an emitting light source using emitter/sensor pads on
the forehead
D) By analyzing exhaled gases to determine oxygen and carbon dioxide levels
Answer: C) By measuring light attenuation from an emitting light source using emitter/sensor
pads on the forehead
Cerebral oximeters utilize emitter/sensor pads similar to reflectance pads applied to the forehead,
which measure light attenuation from the emitting light source.
What is the primary goal of cerebral oximetry monitoring?
A) To ensure NIRS values remain at least 75% of the baseline reading and avoid cerebral
desaturation
B) To accurately measure cerebral blowflow
C) To measure arterial oxygen saturation (SpO₂) continuously
D) To monitor dept of anesthesia
Answer: A
The goal of supportive intervention is to maintain the NIRS value at a minimum of 75% of the
baseline reading.
Cerebral oximetry is most frequently used in which of the following clinical
scenarios? (Select 3)
A) Neonatology
B) Cardiac surgery
C) Carotid endarterectomy
D) Routine outpatient blood pressure monitoring
E) Management of chronic obstructive pulmonary disease (COPD)
Answer: A, B, C
Currently the most frequent uses of NIRS are in neonatology, during cardiac surgery, and during
carotid endarterectomy.
Reference: Nagelhout, J. J.,
Which of the following conditions can decrease the accuracy of information
obtained by Near-Infrared Spectroscopy (NIRS)? (Select 5)
A) Changes in blood pressure
B) Partial pressure of carbon dioxide in arterial blood (PaCO₂)
C) Regional blood volume variations
D) Hemoglobin concentration differences
E) Individual variability, such as differences in extracranial tissue
F) Core body temperature changes
Answer: A, B, C, D, E
As in any monitoring modality there are conditions that can decrease the accuracy of the
information obtained. Changes in blood pressure, partial pressure of carbon dioxide in arterial
blood (PacOi), regional blood volume, hemoglobin concentration, and individual variability (e.g„
differences in extracranial tissue) all effect NIRS readings.
Reference: Nagelhout, J. J., Elisha, S., & Heiner, J. S. (2023).
