Neuroanaesthesia and Neurointensive Care

Anatomical considerations in neuroanaesthesia (Applied clinical physiology and pharmacology) Part 1

Introduction This topic provides an overview of some of the key neuroanatomical considerations that may impact on neuroanaesthesia and neurointensive care. Te topics and discussions are by no means exhaustive but serve as a platform for further exploration via standard neuroanatomical and neurosurgical texts. Applied anatomy of the cranium Anatomical considerations in planning surgical access […]

Anatomical considerations in neuroanaesthesia (Applied clinical physiology and pharmacology) Part 2

Arterial anomalies In post-mortem series, a fully developed arterial circle of Willis exists in about 96% of cadavers, although the communicating arteries will be small in some. Fig. 1.6. CT head scan showing extensive infarction (lowdensity) in the territory of the posterior cerebral artery (arrows). This was the result of compression of the vessel at […]

Anatomical considerations in neuroanaesthesia (Applied clinical physiology and pharmacology) Part 3

Parasympathetic Hie cerebrovascular parasympathetic innervation is supplied from a variety of sources, which include the sphenopalatine and otic ganglia and small clusters of ganglion cells within the cavernous plexus, Vidian and lingual nerves. Vasoactive intestinal polypeptide (VIP), a potent 28 amino acid polypeptide vasodilator that is not dependent on endothelium-derived relaxant factor, has been localized […]

The cerebral circulation (Applied clinical physiology and pharmacology) Part 1

Introduction Management strategies for the prevention of secondary brain injury are based on maintaining the cerebral perfusion pressure. Anaesthetic and surgical interventions alter cerebrovascular physiology profoundly; hence, a good understanding of these changes is crucial to limit the damage following a brain injury. he brain is unique with a high metabolic rate, and its oxygen […]

The cerebral circulation (Applied clinical physiology and pharmacology) Part 2

Flow-metabolism coupling Increases in local neuronal activity are accompanied by increases in regional cerebral metabolic rate (rCMR). Until recently, increases in rCBF and oxygen consumption produced during such functional activation were thought to be closely coupled to the CMR of utilization of oxygen (CMRO2) and glucose (CMRglu). Clinical implications for flow metabolism: functional assessment of […]

The cerebral circulation (Applied clinical physiology and pharmacology) Part 3

Pharmacological modulation of cerebral blood flow Hie importance of understanding drug effects on cere-brovascular physiology cannot be stressed enough. Drugs can exert changes in CBF, CMR and CPP, and therefore on CBV and ICP (Fig. 2.7). hese effects may either be desirable (e.g. reducing intracranial volume (ICV) and ICP) or undesirable (e.g. increasing ICV and […]

The cerebral circulation (Applied clinical physiology and pharmacology) Part 4

Head injury Severe head injury is accompanied by both direct and indirect effects on CBF and metabolism, which show both temporal and spatial variations. Cerebral blood flow may be high, normal or low soon after ictus but is typically reduced. hirty per cent of patients undergoing CBF studies within 6-8 h of a head injury […]

Mechanisms of neuronal injury and cerebral protection (Applied clinical physiology and pharmacology) Part 1

Introduction Ischaemic and traumatic brain injuries are among the most common and important causes of disability and death worldwide. he end point of all cerebral injuries, such as stroke, global cerebral ischaemia during cardiac arrest, cardiac, vascular or brain surgery or head trauma, is the inadequate supply of the brain with oxygen and/or glucose, which […]

Mechanisms of neuronal injury and cerebral protection (Applied clinical physiology and pharmacology) Part 2

General strategies Anti-excitotoxic interventions Glutamate and aspartate are known as excitatory neurotransmitters that stimulate NMDA and AMPA receptors (Ca2+ and Na+ influx, respectively). As the activation of these receptors initiates catabolic intracellular processes, blockade of NMDA and AMPA receptors may protect cerebral tissue. N- Methyl- d-aspartate receptors are generally comprised of NR1/NR2 sub-units, which are […]

Intracranial pressure (Monitoring and imaging) Part 1

Introduction To cover the brain’s metabolic demand, an adequate cerebral blood flow (CBF) is required. he brain is enclosed by the non-expandable skull and an increase in intracranial pressure (ICP) may reduce cerebral perfusion pressure (CPP), and impair CBF leading to cerebral ischaemia. Both CPP and ICP are established treatment targets in neurocritical care. Measurement […]

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