Nervous

A blocked artery and a burst artery present identically — a CT scan splits the path, and the treatments are opposites.

The skull is a rigid box: add volume — blood, edema, tumor — and once compensation runs out, pressure climbs, perfusion falls, and the brain herniates.

Neurons fire in an abnormal, synchronized burst — and at the 5-minute mark, a seizure stops being self-limited and becomes an emergency.

Infection reaches the brain’s coverings — or the brain itself. The bacterial form kills within hours, and the CSF tells you which form you’re facing.

The injury level decides everything — breathing, movement, blood pressure, bladder — and two look-alike shocks plus one hypertensive emergency decide the exam questions.

The substantia nigra stops making dopamine, movement slows and stiffens — and in hospital, a levodopa dose given two hours late can turn a walking patient into a rigid, choking one.

Dementia is the slow, progressive loss of brain function; delirium is the sudden, fluctuating failure of attention that rides on top of it — and the one you can catch, treat, and often reverse.

The immune system strips myelin from brain, optic nerve, and spinal cord axons, so signals slow or stop — in relapses that partly recover, and eventually in a slow progressive decline.

Antibodies jam the acetylcholine receptors at the neuromuscular junction, so voluntary muscles tire with use — from a drooping eyelid to a diaphragm that can no longer breathe.

After an infection, the immune system attacks the peripheral nerves — weakness climbs from the feet, reflexes vanish, and in roughly 20–30% the breathing muscles fail. The nurse’s serial bedside breathing measurements catch it before the pulse oximeter can.

Most headaches are primary and benign — the nurse’s real skill is spotting the few that are not, and stopping the cure from becoming the cause.

The motor neurons that drive voluntary movement and breathing die in both the brain and the spinal cord, so stiffness and brisk reflexes sit beside wasting and twitching; weakness spreads from limb to limb to the throat and the diaphragm while the person usually stays aware of every loss.

Two cranial-nerve disorders of the face. Bell’s palsy is sudden one-sided facial weakness from an inflamed facial nerve (CN VII) — rule out stroke, start steroids early, protect the eye. Trigeminal neuralgia is brief, electric-shock facial pain from a compressed trigeminal nerve (CN V) — triggered by light touch, treated first with carbamazepine.

Bleeding into the space around the brain, usually from a ruptured berry aneurysm. It presents as a sudden, thunderclap “worst headache” — call 911, CT first, then lumbar puncture if the CT is negative. Rebleeding is the early killer until the aneurysm is clipped or coiled; delayed cerebral ischemia (about days 3–14), hydrocephalus and hyponatremia follow. Oral nimodipine for 21 days — never IV.

Nerve damage from years of high blood glucose and lipids. It starts in the toes and spreads upward in a “stocking-glove” pattern — numbness, tingling or burning pain worse at night — and removes the protective pain that warns of foot injury. Daily foot checks, a yearly monofilament foot exam, glucose control and fall precautions prevent ulcers and amputation.

Inflammation of the brain itself — most often viral, with herpes simplex the most common and most treatable sporadic cause, and autoimmune (anti-NMDA receptor) encephalitis now surpassing any single viral cause in young people. Fever and headache progress to confusion, behavior change, seizures and focal deficits. Start IV acyclovir immediately without waiting for results, protect the kidneys while it runs, and prevent mosquito and tick bites.

In adults, most brain tumors are metastases from cancers elsewhere, especially lung and breast; glioblastoma is the most common primary malignant tumor. Symptoms follow location plus pressure: morning headache, new adult seizures, focal deficits and personality change. Dexamethasone for edema, careful post-craniotomy monitoring and temozolomide safety are the nursing core.

An inherited, progressive brain disease caused by an expanded CAG repeat in the huntingtin gene. Each child of a parent with HD has a 50% chance of inheriting it. It causes a triad of involuntary movements (chorea), cognitive decline and psychiatric changes, and there is no cure. Swallowing problems lead to aspiration pneumonia, the most frequent cause of death; suicide is the second. The drugs that calm chorea carry a boxed warning for depression and suicidality.

Too much cerebrospinal fluid (CSF) in the brain’s ventricles, from a blocked flow path, poor absorption or, rarely, overproduction. Acute hydrocephalus raises intracranial pressure and can cause herniation — a medical emergency. Normal pressure hydrocephalus is a slow, adult form with gait trouble, urinary urgency or incontinence and cognitive decline; it is a potentially reversible cause of dementia. Most patients are treated with a shunt, and shunt malfunction or infection needs medical help immediately.