Adult Pop Exam 2

What is HIV?

a retrovirus that attacks WBC

What are AIDS?

HIV Stage 3

CD4+ cells are less than 200

Risk factors w/ HIV

• sharing needles

• unprotected sex

• contact w/ blood

• breast feeding or birthing

Prevention for HIV

• pre-exposure prophylaxis (ARV meds)

• condoms

• HIV testing

What does HIV target within the body?

CD4+ receptors on T-lymphocytes, monocytes, dendritic cells, & brain microglia

Stage 0 of HIV

Period of Infection - Development of HIV-specific antibodies

• may not test positive

• replication occurs

• contagious

Stage 1 of HIV

Acute HIV

• detect HIV RNA & antibodies

• nonspecific symptoms (fever, rash, fatigue)

• HIV established as antibodies cannot fight off infection

• dramatic drop of CD4 T cells

When is the best time to start treating HIV?

Stage 1 to preserve the immune system

What is a viral set point?

equilibrium of HIV levels & immune response (CD4 increases to stable levels)

Stage 2 of HIV

Chronic HIV

• viral set point

• asymptomatic

Stage 3 of HIV

AIDS

• CD4 T cells < 200

• immunocompromised

• deadly w/ no treatment

Stage unknown HIV

no data & AIDS symptoms are not present

HIV Diagnostic Tests

• antibody

• antigen/antibody

• nucleic acid

• blood

Which HIV diagnostic test detects HIV?

antigen/antibody & nucleic acid

Adverse effects of ARV

• hepatoxicity

• nephrotoxicity

• osteopenia

• cardiovascular disease

Reasons for ARV drug resistance

• reg-resistant HIV at initial infection

• selective drug resistance in pts

• inconsistent adherence to HIV meds

Immune reconstitution inflammatory syndrome

an inflammatory reaction from a recovery immune system to an opportunistic infection

• occurs beginning of ARV therapy

• high morbidity

• treatment: anti-inflammatory (cortisone)

S/S of Immune reconstitution inflammatory syndrome

• fever

• respiratory & abdominal S/S

• worsening S/S of opportunistic infection

Respiratory S/S of HIV

• SOB

• dyspnea

• cough

• chest pain

• fever

Respiratory Infections from HIV

• pneumonia

• TB

• CMV

GI S/S of HIV

• loss of appetite

• N/V

• oral candidiasis

• chronic diarrhea

GI conditions from HIV

• candidiasis

• HIV wasting syndrome (severe weight loss)

What is Systemic Lupus Erythematosus (SLE)?

an inflammatory, autoimmune disorder where the body is attacking the nucleus of all cells

Risk factors of SLE

• female gender

• smoking

• alcohol

• UV rays

• medications

• stress

S/S of SLE

• fever

• fatigue

• weight loss

• discoid rashes

• joint pain & swelling

• pericarditis

• lupus nephritis (major cause of mortality)

Treatment of SLE

management of chronic conditions, pain management, nonspecific immunosuppression

Medications for SLE

• methylprednisolone - for acute autoimmune exacerbations

• acetaminophen

• hydroxychloroquine - anti malaria drug for skin lesions & flare ups

• topical cortisone

• methotrexate - common for lupus

Diagnostic for SLE

• Positive ANA

• Pancytopenia (low blood cells)

What is myasthenia gravis?

autoimmune disorder affecting the neuromuscular junction

(antibodies block ACh receptor sites —> muscle weakness)

Ocular Myasthenia gravis

only eyes are affected

• diplopia

• ptosis (drooping eyelids)

Generalized myasthenia gravis

• facial weakness (bland expressions)

• dysphonia (voice impairment)

• dysphagia

• generalized weakness

• respiratory weakness

Diagnosis of Myasthenia gravis

• Tensilon Test (admin edrophonium chloride IV —> S/S resolve)

• ice test (see if ptosis resolves)

• positive ACR antibody

Medications for Myasthenia gravis

• ACh inhibitors

• immunosuppressants

• IVIG (for myasthenic crisis)

Treatment for myasthenia gravis

• therapeutic plasma exchange (to remove antibodies)

• removing thymus

Complications of myasthenia gravis

• myasthenic crisis (exacerbation of weakness)

• neuromuscular respiratory failure

  • treatment: endotracheal intubation & mechanical ventilation

Education of myasthenia gravis

• conserve energy

  • rest before meals

• take ACh meds w/ meals to avoid aspiration

• soft foods

S/S of myasthenic crisis

• respiratory distress

• dysphagia

• dysarthria

• eyelid ptosis

• diplopia

• muscle weakness

S/S of Cholinergic crisis

Salivation & sweating

Lacrimation

Urination

Diarrhea

GI cramps

Emesis

Medications for myasthenia gravis

• methylprednisolone - for acute autoimmune exacerbation

• respiratory therapy

• pyridostigmine - to prevent cholinergic crisis

• eye patch - for double vision

What is multiple sclerosis (MS)?

A progressive disease of the CNS that attacks the myelin sheath

Risk factors of MS

• higher northern latitudes

• Vit D deficiency

• smoking

• obesity

• Epstein-Barr infection

Phenotypes of MS

• relapse-remitting

• secondary progressive

• primary progressive

Common S/S of MS

• lesions

• muscle weakness

• impaired gait/balance

• sensory loss in face or limbs

• bladder issues

• Lhermitte sign (electrical shock down back/limbs)

• visual disturbances

• fatigue

• pain

• spasticity (muscle resistance to stretch)

Diagnostic of MS

• CNS lesions

• elevated immunoglobulins in CSF

• myeline plaques in brain MRI

Medications for MS

• interferon - disease modifying therapy

• methylprednisolone - for autoimmune acute exacerbation

• amantadine - stimulant for fatigue

• eye patch - for double vision

Normal Conduction of Cardiac Cycle

1. SA node - initiates electrical impulse

2. atrial myocardium - impulse spreads & causes atrial depolarization

3. AV node - impulse slows

4. Bundle of His - impulse speeds up

5. L&R Bundle Branches - conduct impulses to ventricles

6. Purkinje fibers - distribute impulses through ventricular walls

P wave

atrial depolarization

Q wave

depolarization of interventricular septum

R wave

depolarization of ventricles

(must be present to determine regularity)

S wave

last phase of ventricular depolarization; atrial repolarization

T wave

ventricular repolarization

U wave

final ventricular repolarization

PR Interval

AV conduction

QRS complex

ventricular depolarization

ST interval

ventricles contract & pump blood; action potentials in ventricles plateau

Approx HR

Count R waves on a 6-sec strip (30 big boxes) & multiple by 10

Enhanced automaticity

cells outside SA node become hyperexcitable —> ectopic beats or tachycardia

Suppressed automaticity

SA node dysfunction can cause bradycardia or sinus arrest

Early afterdepolarizations (EAD)

occur during repolarization & can trigger torsades de pointes (tachycardia)

delayed afterdepolarizations (DAD)

occur after repolarization; can cause premature ventricular contractions

Anatomical Reentry

impulse circulates around a fixed obstacle —> atrial flutter or ventricular tachycardia

Functional Reentry

occurs without a fixed anatomical obstacle (atrial fibrillation)

Blocks

impaired impulse conduction —> heart block

Accessory pathways

bypass normal conduction routes —> pre-excitation syndromes

Fibrosis/Scarring

structural changes in the heart that can slow conduction or blockages (promote reentry)

Hypertrophy

alters cellular electrophysiology & increases arrhythmia risk

How does potassium affect the heart?

affects resting membrane potential & repolarization

How does calcium affect the heart?

influences contractility & automaticity

Sympathetic stimulation of the heart

can increase automaticity & triggered activity

Parasympathetic stimulation of the heart

can slow SA node firing & AV conduction

Ischemia & Infarctions

alter cellular electrophysiology & create slow conduction or blocks (tachy/bradyarrhythmia)

Sinus Bradycardia

<60 bpm w/ reg rhythm

Cause of Sinus Bradycardia

• increased vagal tones

• hypothyroidism meds

• sleep

Treatment for Sinus Bradycardia

• atropine (if symptomatic)

• pacemaker (if persistent)

Premature Ventricular Contractions

• early beat

• wide QRS complex

• no preceding P wave

Cause of Premature Ventricular Contractions

• caffeine

• alcohol

• stress

• electrolyte imbalance

• heart disease

Treatment for Premature Ventricular Contractions

antiarrhythmic meds, avoid triggers

Atrial Fibrillation

• irregular rate & rhythm

• absent P waves

• risk of thromboembolism d/t ineffective atrial contraction

Cause of Atrial Fibrillation

• HTN

• heart disease

• hyperthyroidism

• alcohol

Treatment for Atrial Fibrillation

• rate control (B blockers, Ca channel blockers)

• rhythm control (antiarrhythmics)

• anticogulation

Atrial Flutter

similar to atrial fibrillation; fast but regular rhythm; sawtooth P waves

Ventricular Tachycardia

• 100-250 bpm; regular rhythm

• wide WRS complex

• non-visible P waves

• potential for hemodynamic instability; can degenerate to ventricular fibrillation

Cause of Ventricular Tachycardia

• coronary artery disease

• cardiomyopathy

• electrolyte imbalance

Treatment for Ventricular Tachycardia

• antiarrhythmic meds

• cardioversion

• ICD (implantable cardioverter-defibrillator)

Ventricular Fibrillation

chaotic electrical activity; no discernable waves

Causes of Ventricular Fibrillation

• acute myocardial infarction

• electrolyte imbalance

• drug toxicity

Treatment of Ventricular Fibrillation

• CPR

• advanced cardiac life support

Asystole

no electrical activity; flat line

Cause of Asystole

• end stage of arrhythmias

• severe acidosis

Treatment of Asystole

• CPR

• epinephrine

What is stroke volume?

the amount of blood ejected from the left ventricle

How is stroke volume determined?

• preload

• contractility

• afterload

What is preload?

initial stretching of the heart muscle cells right before contraction

What is contractility?

strength of cardiac contraction

What is afterload?

pressure or resistance the ventricles must overcome to eject blood through the semilunar valves into the systemic circulation

What is Mean Arterial Pressure (MAP)?

indicator of cardiac output & tissue perfusion

Range is 70-100

What is heart failure?

When the heart is unable to pump enough blood to meet the body’s metabolic needs

Risk Factors of HF

• male

• 60+

• cigarettes

• excess weight

• poorly managed diabetes

• metabolic syndrome

What is associated with left-sided HF?

pulmonary congestion

What is associated with right-sided HF?

systemic congestion