HTN Flashcards
What is the FIRST medication response to HTN?
Diuretics
The biggest ways to lower BP with diet
Reduce sodium intake
how do diuretics work
Block the reabsorption of sodium, forcing it’s excretion
Lasix acts where
Loop of henle
Site of GREATEST sodium reabsorption
Thiazides act where
Acts on distal convoluted tubule
More moderate diuresis
Reason for diuretics given in HF
Decrease fluid bulidiup
drop in wt, edema, better breathingetc.
Big concerns when giving lasix
HOTN
Electrolyte depletion
Calcium channe lblockers
Prevent ca from entery muscel cells causing contraction
Limits/slows muscle contraction
- some block channels of arterioles and relax sooth muscel, decreasing BP
- Some decrease heart contractility and wt
NOT useful in HF, because they decrease heart rate and contractility
ACE inhibitors
Block the formation of angiotensin 2
Causing dilation
Blocks the reabsorption of sodium, causing fluid excretion
BP decreases
Prevents ace converting enzyme from converting ang 1 to 2
RAAS system
Renin
Angiotensin 1
ACE converting enzyme
Angiotensin 2 (Vasoconstrictor)
- Causes vasocontriction
Stimulates release of aldosterone
- Causing reabsorption of sodium
Stimulates ADH, increasing fluid retention
Angiotensin receptor blockers
Do not effect angiotensin formation
Instead, attatch to receptors that cause reaction of ADH stimulation and Aldosterone stimulation
Therefore, same effect as ACE inhibs
Beta Blockers
Selective/Non selective
Blocks the beta-anergics recetpors
Slows HR
Used w/ caution in HF
Blocks production of Renin
Decreases Blood pressure
When Beta 1 recepots ar eblocked
Heart rate is slowed - negative chronotrope
and contractility is decreased - negative inotrope
chronotrope
Heart rate
Negative chronotrope = Slows HR
Positive Chronotrope = Increases HR
Inotrope
Contractility
Negative inotrope = decreased contractility
Positive inotrope = Increased Contractility
Most common CVD
HTN
Primary/essential
BP is effected by 3 factors
Cardiac Output
Volume (More = higher BP)
Peripheral resistance - increasing resistance by narrowing BV
Pharmacotherapy for HTN always focuses on reducing one of these factors
HTN risk factors
Risk factors for HTN include:
Diet
Exercise
Age
Smoking
Genetic factors which may alter renal function, and secretion of hormones that regulate blood pressure (angiotensin II, aldosterone, ADH)
Normal BP regulation
Blood pressure is regulated through homeostatic mechanisms
If blood pressure increases, nervous and endocrine mechanisms become active that reduce blood pressure:
CO is decreased
arterioles dialet
Kidneys increase urine output
Vasomotor centre
Regulates activity of SNS
Baroreceptors/chemoreceopters alter CO
Complications of HTN
As blood pressure increases, heart must work harder to eject blood into circulation contributing to the following
Ventricular hypertrophy
Angina, MI, CVA, peripheral vascular disease
Heart failure
Kidney failure
Blindness
Local mediator of vascular tone
Vasoconstrictors (ang 2, endothelin)
Vasodialtors
-Nitorc oxide, prostoglandins
Minute to minute BP regulation
Vasomotor center
Local mediators of vascular tone
Dayu to day regulation of BP
Aldosterone
ADH alter Blood volume
Guidelines for management of HTN
First approach is lifestyle mod
If BP does not change, druags are added
- Diuretics, ACE inhibitors, Angiotensin II receptor blockers, calcium channel blockers, beta-blockers (Sometimes need more than one)
HTN diet
Low alcohol
low Sodium
Non pharm treatments for HTN
Exercise
WT reduction
Diet
Stress reduction
Smoking cessaiton
Diet for HTN
Dietary Approaches to Stop Hypertension
The DASH eating plan includes whole grains, poultry, fish, and nuts, and has low amounts of fats, red meats, sweets, and sugared beverages. It is also high in potassium, calcium, and magnesium, as well as protein and fiber. Eating foods lower in salt and sodium also can reduce blood pressure.
Alcohol Consumption reccomendation
Should be limited to 2 drinks or fewer per day.
Should not exceed 9 drinks per week for women 14 for men.
Why are diuretics often first choice
Bc of few side effects
Adverse effects of diuretics
Electrolyte depletion
Fall risk
3 categories of Ca channel blockers
Areteiole selective durgs
Cardioselective drugs (ie. diltiazem)
Non-selective drugs (ie. Verapamil)
Adverse effects of Ca channel blockers
Adverse effects
Dizziness, flushing, hypotension
Reflex tachycardia (with nifedipine)
Peripheral edema (Bc vasodilation and lower BP)
Dysrhythmias
Exacerbation of heart failure why?
they have a negative inotropic effect (reducing the heart’s strength of contraction) and can slow heart rate
Reflex tachycardia
When BP drops suddenly
HR increases
Prototype Drug Nifedipine (Adalat) (2 of 2)
A Ca channel blocker
Used for HTN and Chronic stable or variant angina
Selectively blocks calcium channels in myocardial and vascular smooth muscle,(including the coronary arteries) causing vasodilation which reduces resistance and blood pressure
Adverse effects
HOTN, flushing, headaches, dizziness, peripheral edema, Hepatotoxicity
Paradoxical angina
Severe hypotension
Exacerbation of heart failure
Nursing considerations for pts recieving calcium channel blockers
Obtain complete health history including allergies and drug history
Obtain baseline vital signs, and ECG
Assess for pulmonary and peripheral edema
Assess neurological status and level of consciousness (LOC)
Planning
Patient to exhibit reduced systolic and diastolic blood pressure
Nursing interventions (What to monitor) for Ca Channel blockers
Monitor :
BP
HR (Reflex tachycardia)
Signs of Ortho HOTN
Signs of HF (Fluid overload0
Monitor wt
I&O
Liver function
Kidney functions
Ace inhibs adverse effects
Persistant cough
HOTN
Hyperkalemia
Angioedema (Hypersensitivity rxn) -constricts airway
What to monitor for pts on ACE inhibs
Obtain complete health history including allergies and drug history
Obtain baseline ECG and vital signs
Assess neurological status and level of consciousness (LOC)
Obtain blood and urine samples for laboratory testing
Monitor Potassium and Sodium
Interventions ACE Inhib
When giving the first dose, monitor for first dose phenomenon syncope
Pbserve for hypersensitivity
Monitor
INterventions for Ace inhibi
Dizziness
S/S of bruising (Can effect platlets)
Monitor for persistant cough
Monitor electrolyte levels
Monitor liver and kidney function
Prototype: Enalapril (Vasotec)
ACE inhib
Has prolonged half life which permits administration once or twice a day.
uses
Adrenregic antogonists
Block Alpha 1 receptors resulting in vasodialtion
Can cause Nausea, tachycardia, palpitations
Beta adrenergic antagonist
Indicated for
Hypertension, dysrhythmias, angina
Mech of action
Decrease CO and HR
Mask signs of Hypoglycemia
Nonspecficic can also act on resp system causing bronchioconstriction
Take BG regularal
Direct acting vasodialtors
Pretty severe adverse effects, only indicated for severe HTN
Relax arteriol smooth muscle causing vasodialtion
Causing reflex tachycardia
Prototype Drug Hydralazine (Apresoline) (1 of 2)
Used in HTN emergencies
Moderate to severe hypertension
Hypertensive emergencies
Acute heart failure
Causes
Causes peripheral vasodilation of arterioles, reducing peripheral resistance and pressure
Adverse effects
Lupus-lke syndromes
What should nurses monitor for vasodilatlors
BP, carefully with titration
Dizziness and LOC
If a drug ends in Lol
Beta Blocker
If it ends in pril
Ace inhibitor
