Sympathetic ANS Flashcards
Where are Nicotinic Receptors found?
- found at the Neuromuscular Junction (NMJ)
- stimulates effectors
Where are Muscarinic Receptors found?
- Found at effectors all throughout the body
- Can stimulate or inhibit a response
Where are alpha 1 receptors found?
- arteries (Vascular smooth muscle)
- eyes
- nose (mucous membranes)
- prostate and bladder
Where are beta 1 receptors found?
- heart
- kidney (Juxtaglomerular Cells)
- eye
Where are beta 2 receptors found?
- Lungs (Bronchioles)
- Skeletal Muscle
- Uterine Smooth Muscle
- Liver
Sympathetic “E”, what does the E stand for?
- involves E activities – exercise, excitement, emergency, and embarrassment
- promotes adjustments during exercise – blood flow to organs is reduced, flow to muscles is increased
What else are adrenergic drugs called?
- Adrenergic
- Sympathetic
- Sympathomimetic
What do adrenergic drugs do?
produce effects that mimic Norepinephrine (NE) or epinephrine at the target site
What are adrenergic drugs and where are they located?
generally agonists at α or β receptors
What are some types of Vasopressors?
epinephrine and adrenaline
What are Vasopressors used for?
- INTRAVENOUS: Advanced Cardiac Life Support (ACLS)
– IV Drip – Used for Shock, hypotension, bradycardia or asystole - SUBCUTANEOUS: Added to local anesthetics
– Lidocaine w/epinephrine subcutaneously - INTRA-MUSCULAR: Anaphylaxis (The Epipen®!)
– IM injection! - INHALED: Asthma (not recommended for routine use)
– Inhaled
How does epinephrine work?
binds non-selectively to alpha and beta receptors
Where does adrenaline affect beta 1 activation?
heart
Where does adrenaline affect beta 2 activation?
lungs
- bronchodilation
Where does adrenaline affect alpha 1 activation?
Vascular Smooth Muscle
- Vasoconstriction (Increased BP)
What are the adverse effects of epinephrine?
- Due to effects on the heart = risk of cardiac complications
– tachycardia (chronotropic+)
– Cardiac Dysrhythmia - EKG abnormalities, ischemia-MI - Due to effects on the vasculature - Hypertension
– can lead to MI, stroke
What are some nursing interventions for epinephrine?
- monitor IV site to ensure proper catheter placement (prevent extravasation)
- Antidote for extravasation: Phentolamine
- Monitor Heart rate, EKG, and Blood pressure (continuously if on IV drip)
What is a selective beta 1 blocker?
metoprolol
“lol”
List some non-selective beta 1 blockers.
- propranolol
- carvedilol
- labetalol
“lol”
List some alpha 1 blockers.
- tamsulosin
- prazosin
“sin”
How do beta 1 antagonists work?
- Block Beta 1 receptors located on heart (also found in the kidneys)
– will lower the heart rate -> lowers blood pressure - Eyes (eye-drops)= miosis, lower IOP!
What is blood pressure?
- Cardiac Output x Systemic Vascular Resistance
- (Heart Rate * Blood Volume) x Artery Resistance
What is orthostatic/postural hypotension?
- defined as a fall in blood pressure brought on by moving from a supine or seated position to an upright position
- the underlying cause is the relaxation of smooth muscle in veins
- commonly seen with anti-hypertensive medications
What are some concerns/signs of orthostatic/postural hypotension?
- dizziness/lightheadedness, passing out/syncope
- huge FALL RISK with geriatric patients!
How do you manage orthostatic/postural hypotension?
Change positions SLOWLY (from sitting to standing). Hold on to something for support in case you get lightheaded. Stay seated until you know how the drug will affect you
What are some adverse effects of metoprolol tartrate (beta 1 antagonist)?
- Orthostatic Hypotension
- Bradycardia leading to decreased cardiac output
– don’t give if someone has bradycardia (<60) - Precipitation of heart failure (Exacerbation)
– decrease in HR and fluid may back up into the lungs or periphery - Mask s/s of hypoglycemia (Diabetes)
– When your blood glucose is too low, Fight or Flight kicks in!
– Adrenaline= ↑HR, anxiety/jittery, sweaty!
– Beta-Blockers mask the HR, anxiety - Cross BBB
– may affect mood (depression, sleep, sexual desire, etc.) - Decrease blood pressure
– Sexual dysfunction (erectile dysfunction, vaginal dryness)
– Decreased libido (impotence)
What do non-selective beta-blockers treat?
- Current or hx of MI (Heart attacks)
- Hypertension, Angina (chest pain)
- Dysrhythmias, Heart failure
- Symptoms of Hyperthyroidism/Thyroid Storm/Thyrotoxicosis
- Anxiety
What do each of the non-selective beta-blockers do?
Timolol: Glaucoma Eye Drops (Tim has glaucoma)
Propranolol: Commonly used by Professionals
Carvedilol: Mainly used in Cardiac Conditions
Labetalol: Commonly used in Labor and Delivery (HTN management in pregnant patients)
Where are each of the non-selective beta-blocker receptors located?
- Block Beta 1 receptors located on the heart
- May Block Beta 2 receptors in the lungs, skeletal muscle, liver
- May Block alpha 1 receptors- relax vascular smooth muscle (arteries)
What are the two types of Glaucoma?
Open and Narrow-Angle
What is Glaucoma?
- increased Intra-Ocular Pressure (IOP) aqueous humor in the eye
- is a CHRONIC CONDITION, treat for life
How do pupils affect Glaucoma?
- IF pupil dilation occurs (mydriasis) this increases IOP
– WORSENS GLAUCOMA - IF pupil constriction occurs (miosis) this decreases IOP
– HELPS TREAT GLAUCOMA
What does Timolol do?
Beta Blocker eye drops block adrenaline in the eye
What are the adverse effects of non-selective β blockers in β1?
- Bradycardia leading to decreased CO
- Hypotension
- Precipitation of heart failure (fluid retention)
- Mask the S/S of hypoglycemia in diabetes
– Tremor/palpitations
What are the adverse effects of non-selective β blockers in β2?
- Bronchoconstriction (bad for Asthma/COPD)
- Prevent glycogenolysis in the liver (further complicates hypoglycemia)
What is the contraindication of non-selective β blockers?
Asthma/COPD
What is Tamsulosin used to treat?
- MAIN USE #1: Benign prostatic hyperplasia (BPH)
- MAIN USE # 2: Bladder Outlet Obstruction (kidney stones)
What is Prazosin used to treat?
- Main use Hypertension
– Note: Guidelines no longer recommend these as 1st line
What do α1 antagonists “blockers” do?
- prevents activation of α1 receptors (antagonist)
- there are subtype α1 receptors
Where are α1 antagonists “blockers” located?
- some are found in peripheral vascular smooth muscle (arteries)
- some are found in Bladder/Urethra/Prostate
What does it mean that α1 blockers are selective for or non-selective?
a drug that targets the bladder may also lower someone’s blood pressure
What is reflex tachycardia commonly seen with?
Commonly seen with Anti-hypertensive drugs that DON’T WORK DIRECTLY ON THE HEART
What causes reflex tachycardia?
dilation of arteries/veins (sudden drop in BP)
Why is reflex tachycardia undesirable?
- Tachycardia can put an unacceptable burden on the heart
- If the vasodilator were given to reduce blood pressure, tachycardia would raise pressure and thereby negate the desired effect
How can you treat reflex tachycardia?
To help prevent vasodilator-induced reflex tachycardia, patients can be pretreated with a beta-blocker (ex: propranolol), which blocks sympathetic stimulation of the heart
What is a common adverse effect of α1 antagonists “blockers”?
- First dose Orthostatic/postural hypotension
– Almost always happens with the first dose
» Medical textbooks call this, the “First Dose Phenomenon”
– IMPORTANT COUNSELLING POINT
» We don’t want our patients to fall!
» Sometimes patients take it at night to reduce the risk
What is a rare adverse effect of α1 antagonists “blockers”?
Reflex tachycardia (resulting from the sudden drop in blood pressure)
What are some other adverse effects of α1 antagonists “blockers”?
- Sexual dysfunction may occur in patients with all anti-hypertensive medications
– This drug class is noted to cause retrograde or inhibited ejaculation - Rebound hypertension can occur if any anti-hypertensive is stopped suddenly (never stop a blood pressure medication suddenly)
– Think of the Beta-Blocker Boxed Warning
When should α1 antagonists “blockers” be given?
at bedtime to reduce risk for postural/orthostatic hypotension
