Medical Surgical I (NURS-301 Liberty University) Test 2

What are the major differences between Type 1 and Type 2 HIV?

Type 1- more prevalent in US, Canada, and Europe and more responsive to drugs

Type 2- more prevalent in 3rd world countries and resistant to ART

When blood is the mode of transmission for HIV, what ways are most commonly seen?

Blood products before 1985

Needle sharing

Blood sharing in 3rd world countries

How does HIV pass from mother to baby?

Through placenta (typically untreated or advanced HIV)

During birth (lots of fluid exchange)

While breastfeeding

How many new cases of HIV are there a year?

~56k

What gender is more likely to have HIV?

Male

What kinds of cells are affected by CD4 (or lack thereof)?

T helper cells, lymphocytes, and monocytes

How does HIV replicate?

Reverse transcriptase that alters the cells genome that then replicates as HIV instead of a healthy cell

What are the lengths of the stages of HIV?

Acute- Occurs 1-3 weeks post infection for 1-2 weeks

Chronic asymptomatic- 2 months-8 years

Chronic symptomatic- 8-10 years

AIDS- 10+ years

What does the viral load and CD4 count do during the acute stage?

CD4 temporarily drops then returns to baseline and viral load rises quickly

What is a viral load associated with HIV?

200-500

What is a CD4 count associated with HIV?

>500

What is a CD4 count associated with AIDS?

What opportunistic infections do you very rarely see in anyone but AIDS patients?

Pneumocystis jiroveci pneumonia

Cryptococcal meningitis

Cytomegalovirus retinitis

What are signs of chronic HIV infection?

Chronic diarrhea, propensity to infection, lymphadenopathy, neurological changes, persistent night sweats and fever, candidiasis, kaposi sarcoma, and oral hairy leukoplakia

Are OraSure and OraQuick 100% indicative of a patient having HIV?

No: it shows that they have been exposed but not if they have contracted it. It requires further testing if they show positive

When is HIV detectable?

10 days after exposure

What is a CD4 count without any HIV?

800-1200

What is viral load in early chronic phase?

200-500

What does a high viral load (5k-10k) mean?

the disease is progressing

What types of drugs are used for ART?

-NRTIs - Nucleoside Reverse Transcriptase Inhibitors

-NNRTIs - Non-Nucleoside Reverse Transcriptase Inhibitors

-Protease Inhibitors

-Integrase Inhibitors

-Fusion Inhibitors

Pre exposure HIV drugs

Descovy (male only)

Truvada (both genders)

If a woman comes into the ER scared because she had sex with an HIV positive man that day what do you do? What about if it's five days ago?

Start ART meds for 28 days- tenofovir, emtricitabine, and either raltegravir or dolutegravir and test at 10 days

Test at day 10 if over 72 hours

Nursing goals for HIV

Keep viral load low

Maintain immune function

Improve quality of life

Prevent opportunistic infections

Reduce disability

What are the differences between antigens and haptens?

Antigens: toxic on it's own, produce immune responses

Haptens: Require carrier molecule, cannot produce immune response on it's own

Types of antigens

Bacteria

Viruses

Fungi

Prions

Parasites

Examples of natural (innate) immunity

Skin and mucous membranes

Is breastfeeding passive or active acquired immunity for infants?

Mostly passive but shown to have some active immunity

Example of active acquired immunity?

Having chicken pox, the common cold, stomach bugs, vaccines

Examples of passive acquired immunity?

In utero immunoglobulin transfers

Anti venom

Does passive acquired immunity last long?

No

What cells does humoral immunity use?

B cells

How long does it take humoral immunity to work when exposed to an antigen the first time? Second?

4-8 days for first response

1-3 days when re exposed

What does humoral immunity primarily protect against?

Bacteria

Respiratory pathogens

GI pathogens

Extracellular viruses

What cells does cell mediated immunity use?

T cells

How to T cells work to destroy pathologic organisms? What are their primary targets?

Produce sensitized T lymphocytes

Cancer cells, intracellular viruses, funguses, transplanted tissues

What big downsides do cell mediated responses cause?

Rejection of transplanted tissues and contact hypersensitivity reactions

Aging causes what major effects on immune systems?

Higher rate of infections and tumors and need for higher doses for vaccines to be effective (high dose flu vaccines)

What 2 main types of hypersensitivity reactions are there? Examples of each?

Type 1: IgE mediated Ex: seasonal allergies, food allergies, poison ivy

Type 2: Cytotoxic reaction Ex: blood transfusion reaction

What is the main chemical mediator associated with IgE reactions?

Histamine

Symptoms of IgE reaction

Increased secretions

Itching

Smooth muscle contraction

Increased vascular permeability

Order of operations for anaphylaxis treatment

1 Remove cause

2 Secure airway and administer oxygen

3 Epinephrine

4 Maintain circulatory volume and access

5 (longer term) Albuterol, diphenhydramine, corticosteroids

Order of operations for treating allergies

Avoid triggers

Treat symptoms

Immunotherapy

Chronic allergy medicine classes

Antihistamines

Decongestant/sympathomimetics

Corticosteroids

Topical Anti pruritics

Mast cell stabilizers

Example of topical anti pruritics

calamine lotion

Example of allergy coricosteroid

Flonase

Sympathomimetic/Decongestants most commonly used

Epinephrine (Adrenalin)

Pseudoephedrine (Sudafed)

Mast Cell stabilizing drugs most commonly used

Cromolyn (Intal, Nasalcrom, Rynacrom)

Nedocromil (Tilade)

What are the two types of latex allergy?

Type 1 occurs within minutes

Type 4 is delayed by 6-48 hours

What is apheresis used for?

Blood components are separated to remove autoimmune cells

What is the difference between primary and secondary immunodeficiencies?

Primary is lack of immune cells at birth

Secondary is decreased immune calls due to illness or treatment of illness (ex: chemo, AIDS, burns, sepsis, excessive stress or obesity, etc.)

Who cannot have a live vaccine?

Immunocompromised people

Precautions for vaccines include:

Hx of anaphylatic reaction

Fever

Allergy to eggs

Immunocompromised state

Can you get the flu from the flu shot?

NO! You are just feeling malaise, myalgia, soreness, and a low grade fever

What is the direction of blood flow from the vena cava to the aorta?

Vena cava

Rt Atrium

Tricuspid valve

Rt Ventricle

Pulmonic valve

Pulmonary artery to lungs

Pulmonary vein

Left atrium

Mitral valve

Left ventricle

Aortic valve

Aorta

What is the entry point for blood flow to the coronary arteries? Where is is?

The sinuses of Valsalva which is located right above the cusps of the aortic valve

What artery is the most likely to kill you if it gets blocked? What is it's nickname?

Left anterior descending artery of the heart

The Widow maker

What is the difference between ischemia and infarction?

Ischemia is inadequate O2 to tissues that is reversible

Infarction is permanent tissue loss and blood supply loss from continued ischemia

Why is the SA node placed in the top corner of the atria and the AV node in the opposit bottom corner?

To allow for time for the atria to squeeze before the impulse reaches the ventricles

What is the function of the bundle of HIs/Purkinje fibers?

To evenly distribute the action potential for a full squeeze of the ventricles

What does the P wave represent?

atrial depolarization

What does the PR interval represent?

The time required for the impulse to travel from the atria through the AV node

What does the QRS complex represent?

ventricular depolarization

What does the T wave represent?

ventricular repolarization

What does the U wave represent?

Repolarization abnormalities of low potassium (hypokalemia)

Why do you not see the repolarization of the atria on an EKG?

Because the QRS is so large that it hides the repolarization

How many seconds is a small box on an EKG?

0.04 seconds

How many seconds is a large box on an EKG?

0.2 seconds

How many seconds is a normal P wave?

0.06-0.12 seconds

How many seconds is a normal PR interval?

0.12-0.2 seconds

How many seconds is a normal QRS complex?

0.04-0.12 seconds

How to you measure heart rate?

Top of P to top of P or R to R

Bradycardia is a heart rate of what?

What is a normal heart rate?

60-100

Tachycardia is a heart rate of what?

>100

Sinus tachycardia, sinus bradycardia, and normal sinus rhythm have what in common?

Their R to R is the same for the entire strip

Atrial flutter is how fast of a rate?

Could be a normal QRS rate but has 250-400 firings of the atria per minute

What is the key visual aspect that makes atrial flutter easy to spot?

Many P waves before QRS complexes start aka a sawtooth pattern

Can atrial flutter be regular?

Yes! They may have consistently three P waves before a QRS but they also may be irregular and not have a discernable pattern

When Atrial fibrillation is occurring what is going on in the atria?

The atria are quivering since more than just the SA node is firing therefore not allowing the atria to fully depolarize and empty as consistently

When you look at an A fib EKG strip what do you see?

An irregular rate with no discernable P wave

Can A fib be controlled? If so what dictates it being under control?

Yes! If the rate is

What does ventricular tachycardia look like on an EKG?

No visible P wave

No visible T wave

A QRS complex that does not look like a QRS, it looks more like rounded waves

Is usually a regular rate

What does ventricular fibrillation look like?

No discernable anything, looks like squiggles

What does ST depression indicate?

Myocardial ischemia

What does ST elevation indicate?

Myocardial infarction that has a complete blockage of a vessel

Can you still be having a heart attack if there is no ST elevation?

Yes! There may still be a blockage but it does not occlude the entire vessel

What is the equation for cardiac output?

Heat rate x stroke volume

What is a normal cardiac output?

4-8L/min

What can you do to increase Cardiac output?

increase heart rate or stroke volume or both

What is the most important term to associate with preload?

Volume

What is preload?

The amount of blood left in the ventricles at the end of diastole and before the next contraction

What increases preload?

Fluid overload (hypervolemia)

Valve regurgitation

Pump failure (CHF)

What decreases preload?

Dehydration (low blood volume)

Bleeding

Shock

What words should you associate with afterload?

Vascular resistance

What causes increased afterload?

Vasoconstriction

Hypertension

Medicines that cause vasoconstriction

What causes decreased afterload?

vasodilation

hypotension

shock

What word should you associate with contractility?

Squeeze

What increases contractility?

Sympathetic nervous system (fight or flight/norepinephrine)

Positive inotropes

Digoxin

What decreases contractility?

Heart failure (too much fluid to properly squeeze)

Age

Increasing preload, afterload, or contractility increases ________of the heart and increases the need for ______

the workload

oxygen