Neurology and Renal/Urology Practice Flashcards

Cerebrovascular Accident (CVA)

A sudden loss of brain function caused by disrupted blood supply, classified into two types: Ischemic ($90\%$ of cases) and Hemorrhagic ($10\%$ of cases).

Thrombotic Ischemic Stroke

A type of stroke where a blood clot (thrombus) forms in a cerebral artery, often due to atherosclerosis, obstructing blood flow and leadings to ischemia and brain tissue death.

Intracranial Pressure (ICP)

The pressure exerted by the brain tissue, blood, and cerebrospinal fluid inside the skull; the normal range is $5-15\,mmHg$.

Monro-Kellie Doctrine

A principle stating the skull is a fixed box where an increase in volume of one component (brain, blood, or CSF) must be compensated by the others, or intracranial pressure will rise.

Cerebral Perfusion Pressure (CPP)

The net pressure gradient causing blood flow to the brain, calculated by the formula: $CPP = MAP - ICP$. The normal range is $60-100\,mmHg$.

Brain Ischemia Threshold (CPP)

When $CPP$ drops below $50\,mmHg$, neurons lack O2/glucose, leading to failure of $Na/K$ pumps, cytotoxic edema, and irreversible cell death.

Brain Arterial Systems

The anterior circulation involves the internal carotid arteries, while the posterior circulation involves the vertebral, basilar, and posterior cerebral arteries.

Watershed Infarct

Ischemic damage occurring in the border zones between major cerebral artery territories during periods of systemic hypotension or hypoperfusion.

Cerebrospinal Fluid (CSF)

Clear fluid within the ventricles and subarachnoid space that cushions the CNS, removes waste, provides buoyancy, and maintains the chemical environment.

Bacterial Meningitis Pathophysiology

Bacteria in the subarachnoid space trigger inflammation, increasing Blood-Brain Barrier permeability, neutrophil infiltration, and exudate formation, leading to increased ICP.

Glasgow Coma Scale (GCS)

A clinical scale measuring level of consciousness based on eye opening, verbal response, and motor response, with scores ranging from $3$ to $15$.

GCS score of 3

Indicates severe diffuse brain injury or brainstem dysfunction, characterized by deep coma and failure of the ascending reticular activating system and cortical function.

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