Medical and Diagnostic Terms: Physical Exam, Blood Tests, Electrocardiography, Electroencephalography, and Seizures

Inspection

General observation of appearance, speech, aptitude, abilities, and overall behavior during a physical exam.

Auscultation

Listening to body sounds with the ears or a stethoscope.

Palpation

Using hands and fingers to feel structures beneath the skin.

Percussion

Tapping the body to assess underlying structures.

Physical Examination

Order includes inspection, auscultation, palpation, and percussion.

Plasma

Liquid portion of blood obtained after adding anticoagulant and centrifugation; contains clotting factors.

Serum

Liquid remaining after blood clots and is centrifuged; lacks fibrinogen and clotting factors.

Urinalysis

Test used to detect kidney disease, diabetes, UTI, and other conditions using urine.

Foamy Urine

Suggests protein is present in the urine.

ECG (Electrocardiogram)

Recording of the heart's electrical activity.

P Wave

Atrial depolarization; indicates sinus rhythm is present.

No P Wave

No sinus rhythm.

QRS Complex

Ventricular depolarization.

T Wave

Ventricular repolarization.

Chest X-ray

Fast imaging test used to evaluate lungs, heart, and chest structures.

Hyponatremia

Abnormally low plasma sodium concentration.

Hypernatremia

Abnormally high plasma sodium concentration.

Cause of Hyponatremia

Too much water relative to sodium.

Cause of Hypernatremia

Too little water relative to sodium.

Hyponatremia ECF Osmolarity

Decreased.

Hyponatremia Water Movement

Water moves from ECF into cells.

Hyponatremia Cell Volume

Cells swell.

Major Concern in Hyponatremia

Cerebral edema.

Symptoms of Hyponatremic Encephalopathy

Confusion, seizures, coma, increased intracranial pressure, myoclonus.

Acute Hyponatremia

Rapid development with significant brain swelling and little time for adaptation.

Chronic Hyponatremia

Develops over days to weeks with partial brain adaptation.

Hypertonic Solution Effect

Water moves from ICF to ECF; cells shrink.

Hypotonic Solution Effect

Water moves from ECF to ICF; cells swell.

Isotonic Solution Effect

No net water movement; cell volume unchanged.

Intracellular Fluid (ICF)

Fluid inside cells; high potassium and low sodium.

Extracellular Fluid (ECF)

Fluid outside cells; high sodium and chloride.

Major Intracellular Cation

Potassium (K+).

Major Extracellular Cation

Sodium (Na+).

Water Movement Rule

Water moves toward the compartment with higher osmolarity.

EEG

Recording of summed electrical activity of the cerebral cortex.

Major Source of EEG Signal

Synaptic potentials.

EEG Amplitude Determined By

Number of active synapses and synchrony of activity.

Synchronized EEG

High amplitude, slower waves.

Desynchronized EEG

Low amplitude, faster waves.

Awake EEG

Fast, low-amplitude, desynchronized activity.

Deep Sleep EEG

Slow, high-amplitude, synchronized activity.

Generalized Seizure

Involves both sides of the brain from onset.

Focal Seizure

Begins in a localized brain region.

Jacksonian March

Spread of seizure symptoms from one body part to another as activity spreads through cortex.

Convulsive Seizure

Seizure with prominent involuntary muscle contractions.

Nonconvulsive Seizure

Abnormal brain activity without major convulsions.

Petit Mal Seizure

Generalized nonconvulsive seizure causing brief staring spells.

Grand Mal Seizure

Generalized tonic-clonic seizure with widespread brain involvement.

Tonic Phase

Muscles become stiff and contract continuously.

Clonic Phase

Repetitive jerking contractions and relaxations.

Action Potential

Rapid temporary change in membrane voltage used for signaling.

Synaptic Potential

Change in postsynaptic membrane voltage caused by neurotransmitters.

Epilepsy

Chronic disorder characterized by recurrent seizures.

Paroxysmal

Sudden attack or sharp worsening of symptoms.

Motor Seizure

Abnormal movement caused by abnormal electrical activity.

Atrial Fibrillation

Irregular and often rapid rhythm originating in atria.

Normal Cerebral Blood Flow Receives

About 15% of cardiac output.

Brain Oxygen Consumption

About 20% of the body's oxygen.

Brain Glucose Consumption

About 25% of the body's glucose.

Generalized Seizure CBF

Can increase to 45-60% of cardiac output.

Ischemic Stroke

Blockage of a blood vessel reducing cerebral blood flow.

Thrombotic Stroke

Clot forms and remains at site of obstruction.

Embolic Stroke

Clot forms elsewhere and travels to brain.

Hemorrhagic Stroke

Rupture of blood vessel causing bleeding.

Hypoxia

Inadequate oxygen reaching tissue.

Ischemia

Inadequate blood flow causing low oxygen and low glucose delivery.

Why Ischemia Worse Than Hypoxia

Tissue loses delivery of both oxygen and glucose.

EEG Suppression in Ischemia

Synaptic transmission fails early due to energy failure.

ATP Decrease Effect

Failure of ATP-dependent ion pumps.

Ischemic Depolarization

Collapse of ion gradients causing membrane potential to approach 0 mV.

Ion Changes in Ischemia

Na+ enters, Ca2+ enters, K+ leaves.

Cytotoxic Edema

Cell swelling caused by water following sodium into cells.

Ischemic Core

Central region with irreversible injury and severe blood flow reduction.

Penumbra

Surrounding tissue that is impaired but potentially salvageable.

Spreading Depression

Slowly propagating wave of neuronal depolarization.

Peri-Infarct Depolarization

Repeated spreading depolarizations in ischemic penumbra.

Selective Vulnerability

Some neurons are more sensitive to ischemia than others.

Delayed Neuronal Death

Neurons may die days after ischemic injury.

Major Ischemic Cascade

Energy failure, depolarization, calcium influx, swelling, cell death.

Major Regulators of Cerebral Blood Flow

CO2, H+, adenosine, extracellular K+.

Increased CO2 Effect on CBF

Increases cerebral blood flow.

Decreased CO2 Effect on CBF

Decreases cerebral blood flow.

Mr. Murmur Diagnosis

Myocardial infarction progressing to impaired cardiac function.

ST-Segment Elevation Cause

Transmural myocardial ischemia causing electrical differences between healthy and injured myocardium.

Troponin-I Elevation

Marker of cardiomyocyte damage.

CPK-MB Elevation

Marker of myocardial damage.

Myoglobin Elevation

Marker of muscle injury including myocardial infarction.

Holosystolic Murmur After MI

Suggests ventricular septal rupture.

Ventricular Septal Rupture

Left-to-right shunt causing harsh holosystolic murmur.

William Short Diagnosis

Viral dilated cardiomyopathy causing congestive heart failure.

Dilated Cardiomyopathy

Large chambers, thin walls, decreased contractility, reduced ejection fraction.

Cardiac Hypertrophy

Thickened heart muscle with relatively preserved ejection fraction.

Orthopnea

Shortness of breath when lying flat.

Paroxysmal Nocturnal Dyspnea

Sudden nighttime episodes of severe shortness of breath.

S3 Gallop

Sign of volume overload and systolic heart failure.

Displaced PMI

Indicates enlarged or dilated heart.

Bibasilar Crackles

Sign of pulmonary congestion in heart failure.

Elevated JVP

Sign of systemic venous congestion.

Ankle Edema

Peripheral edema caused by increased venous pressure.

CHF Pathway

Viral illness → myocarditis → dilated cardiomyopathy → decreased contractility → reduced ejection fraction → congestive heart failure.