Cerebral blood flow and the injured brain: how should we monitor and manipulate it?

Abstract

Current neurocritical care management strategies are focused on the prevention and limitation of secondary brain injury where neuronal insult continues to evolve during the hours and days after the primary injury. Appropriately chosen multimodal monitoring including CBF and management measures can result in reduction in mortality and morbidity.

Circulatory and Respiratory Parameters during Acute Endovascular Stroke Therapy in Conscious Sedation or General Anesthesia

“…The method does have its limitations, such as the difficulty to define thresholds, 35 extracranial signal contamination, limited spatial capture by forehead placement, and interference by ambient lighting. 36 NIRS appeared helpful to reflect O 2 administration (CS) or ventilation settings (GA) to achieve sufficient systemic (including cerebral) oxygenation in all patients. Drastic changes as caused by malpositioning of the orotracheal tube or severe hyperventilation with subsequent cerebral vasoconstriction in single cases that did not occur in this study were directly displayed by NIRS (Hametner et al submitted).…”

Noninvasive Measurement of Cerebral Blood Flow Under Anesthesia Using Arterial Spin Labeling MRI: A Pilot Study

“…15 Other methods of CBF measurement and the perfusion include single photon emission computerized tomography imaging, xenon computerized tomography (CT), CT perfusion scan, and MR perfusion imaging. 16 Among these, CT perfusion and xenon CT provide absolute CBF measurements, whereas single photon emission computerized tomography imaging provides relative CBF measurements. However, unlike ASL-MRI, these techniques do carry a risk of radiation.…”

Near-infrared spectroscopy (NIRS) as a useful tool to evaluate the treatment efficacy of positive airways pressure therapy in patients with obstructive sleep apnea syndrome (OSAS): A pilot study

“…Several well-established neuroimaging methodologies including computed tomography (CT), functional magnetic resonance imaging (fMRI), positron emission tomography (PET), single-photon emission computed tomography (SPECT), transcranial Doppler (TCD), and near-infrared spectroscopy (NIRS) have been widely used to study cerebral autoregulation mechanism under various physiological and pathological states in both healthy subjects and patients. [12][13][14][15][16][17][18][19] Several attempts to determine cerebral hemodynamics in OSA using these techniques faced some limitations. CT, fMRI, PET and SPECT are only suitable to study the cerebral hemodynamics in OSA patients during wakefulness, [20][21][22] but not during all night sleep due to obvious reasons including safety issues, radiation, high magnetic¯elds, loud noises, motion artifacts, compatibility of CPAP device, etc.…”