hypertension Flashcards
Hypertension
What are some modifiable and non-modifiable risk factors for HTN
Smoking, ETOH, sedentary lifestyle, poor diet, body composition (to an extent), NSAIDS, steroids, decongestants, oral contraceptives, ETOH, stimulants
age fmhx, ethnicity
Hypertension
RAAS pathway
Volume depletion or sympathetic stimulation –> renin –> angiotensinogen –> angiotensin 1, converted to angiotensin 2 (vasoconstrictor) –> aldosterone from adrenal cortex simulates reabsorption of water and sodium and excretion of potassium in the distal convoluted tubules.
Hyperkalemia increases aldosterone.
Hpokalemia lowers aldosterone production.
Hypertension
what are some causes of secondary HTN
- Primary kidney disease
- Primary aldosteronism
- Cushing’s
- Renovascular hypertension
- OSA
- Thyroid disorders
- Coarctation of aorta
Hypertension
what are some medications that raise BP
OCP, NSAIDS, Antidepressants, Corticosteroids
Hypertension
When to investigate for 2nd HTN
- No nocturnal fall in BP during 24 hour ABPM
- New onset at especially young or old age (esp no family hx)
- Abrupt onset or abrupt changes in previously controlled HTN
- Resistant HTN
- Abdominal bruit (renovascular), low serum K+, or other clues
Hypertension
How to take a proper BP measurement
- no smoking or caffeine in last 30 min
- sit quietly for minimum 5 min before measuring
- measure BP both arms
- select arm with high reading for future measurements
- Sitting position w/ back support
- Appropriate cuff size w/ middle of cuff at heart level
- Lower edge of cuff 3 cm above elbow crease, bladder centered
- Do not talk, legs uncrossed and feet flat on the floor
- Intervals Q 1-2 minutes
- AOBP preferred > OBPM
- ABPM preferred > HBPM
Hypertension
What is considered High Risk patient per HTN Canada?
- clinical or subclinical CVD
- CKD
- FRS > 15%
- age > 75
Hypertension
What is a hypertension emergency?
Hypertensive emergency (severely elevated BP >180/120) in the presence of:
- Acute head trauma
- Neurologic symptoms (agitation, delirium, vision disturbance)
- N/V
- CP / SOB
- Acute severe back pain (?aortic dissection)
- Pregnancy
- Hyperadrenergic drugs (cocaine, amphetamines)
*BC Guidelines defines HTN emergency as > 130 diastolic
Hypertension
HTN Canada definitions and threshold for diagnosis.
Define and provide cutoff for:
AOBP
OBPM
AOBP
automated:
automated and averaged 3-6 intervals
SBP ≥135
DBP≥85
* over 3-5 visits
or if >180/110 (then may dx 1st visit)
OBPM
automated or auscultatory single readings, do 3 and discard the 1st
SBP ≥140
DBP≥90
* over 3-5 visits
or if >180/110 (then may dx 1st visit)
Hypertension
HTN Canada definitions and threshold for diagnosis.
Define and provide cutoff for:
ABPM
HBPM
ABPM
- ambulatory
- Consider for borderline/variable measurements, significant anxiety, white coat syndrome
24 -hour preferred for out of office dx
24-hour
SBP ≥130
DBP≥80
Daytime
SBP ≥135
DBP≥85
HBPM:
Home BP monitoring:
monitor 2 readings BID X 7 days, discard first day and average the rest.
SBP >135
DBP >85
Hypertension
Labs & investigations for HTN monitoring
CBC, electrolytes, BUN/Cr, TSH, non-fasting lipids, UA (hematuria), fasting glucose or A1C, urine ACR, ECG , annual
Hypertension
Desirable BP per BC Guidelines
- general guide: AOBP <135/85 desirable for adult with no comorbid conditions/DM/CKD/end organ damage
- adults 60+: desirable BP AOBP <145/85
Hypertension
How is resistant BP defined
Resistant HTN defined as BP above target that is managed by 3 or more meds at optimal doses.
Hypertension
When to consider HBPM
- Inadequately controlled
- Diabetes mellitus
- Chronic kidney disease
- Suspected non-adherence
- Demonstrated or suspected white coat effect
- BP controlled in the office but not at home (masked hypertension)
Hypertension
What are 5 common causes of resistant HTN
- Medication nonadherence
- alcohol use (>3 drinks per day)
- sleep apnea
- renal insufficiency
- mineralocorticoid excess
Hypertension
BC guidelines annual HTN visit - what to review w/ pt
- adherence and side effect to meds
- lifestyle change behaviours
- risk factors
- evidence of target organ damage
Hypertension
Follow-up for HTN per BC Guidelines
- f/u in 2 weeks after initiation: eGFR, adherence, side effects
- *review q1-2 months until BP in desired range x 2 consecutive visits
- review q3-6 months if stable
- establish minimum dose of med needed for desired BP (consider reducing/discontinuing)
- monitor kidney function when meds are adjusted
Hypertension
Who to refer for HTN
- Resistant HTN (IM or cardiology)
- pregnancy (obstetrician)
- sudden onset in elderly
- abnormal nocturnal BP differences (BP dip or increase in nocturnal BP increases risk for CVD)
- symptoms suggestive of secondary HTN
- > 15 mm Hg difference between each arm
Hypertension
What are the HTN Canada health behaviour recommendations?
- Physical activity 30-60 minutes, moderate intensity (walking, cycling, swimming), 4-7 days/week
- Weight reduction (recommended ‘normal’ BMI [18.5-24.9] and waist circumference [<102 m or < 88 f)
- Alcohol: no safe limit. Recommend < 2 drinks/day
- Diet: DASH, dietary potassium
- Salt: <2000 mg/day (previously was less than 1500 mg)
- Relaxation (individualized CBT)
Smoking cessation
Hypertension
HTN Canada: when to initiate therapy
High risk:
SBP > 129
DM
SBP > 129
DBP > 79
Moderate risk
SBP > 139
DBP > 89
Low risk
SBP > 159
DBP > 99
Hypertension
BC Guidelines on initiation of therapy for low to moderate risk (FRS < 15%)
> 179/109
Hypertension
what does HTN canada recommend for pregnancy?
nifidipine XL
can also use BB
Hypertension
What are 5 first-line therapy options for per HTN Canada (without compelling indications for specific agents)
- Thiazide-like diuretic (less costly)
- ACE-I or ARB
- CCB (long-acting only)
- BB (not for < 60 yoa)
Hypertension
Conditions w/ specific HTN Canada recommendations
○ Isolated diastolic HTN (rule out hypothyroid), or Isolated systolic HTN (rule out hyperthyroid)
○ DM & DM with microalbuminuria or renal disease
○ CAD, recent MI, HF, LVH, CVA/TIA, PAD
○ CKD with proteinuria (without DM)
○Preconception, lactation, pregnancy
Hypertension
Hydrochlorothiazide
Generic: hydrochlorothiazide
Trade:
Classification: Thiazide-like diuretic
Therapeutic Indication:HTN, edema, HF. *first line diabetes WITHOUT complications/CV risk factors (alternative to ACE-I/ARB)
Used in combination with other medications for SBP >160 and/or DBP >100.
MOA: Inhibits sodium reabsorption primarily in distal convoluted tubule. Causes excretion of sodium, water, potassium and hydrogen ions, and increased urine production. Results in decreased extracellular fluid volume and reduced afterload and cardiac output.
Dosing:
Initial 12.5-25 mg once daily
Titrate dose based on response. Doses >25 mg/day not recommended.
Adverse S/E:
- Electrolyte disturbances
- gout or renal calculi from hyperuricemia
- glucose intolerance
- transient hyperlipidemia
- hypersensitivity reactions
- ocular effects
- Photosensitivity (advise re: sun safety)
- skin cancer (4x risk of non-melanoma skin cancer eg SCC and BCC)
Contraindicated: anuria, hypersensitivity
Precautions: pre-existing electrolyte abnormalities, hepatic dysfunction, glucose intolerance, predisposed to gout, renal impairment or arrhythmia. Replace thiazide diuretics with loop diuretics when GFR <30 mL/minute.
Monitoring: Na, K, BUN, creatinine, glucose. Therapeutic effect: Hypotension and decreased extracellular volume. Approximately 4 weeks for optimal effect.
BEER’s Criteria:
Geriatric considerations:caution in use > 65 (may trigger SIADH)
Hypertension
Ramipril
Generic: ramipril
Trade:
Classification: ACE-I
Therapeutic Indication:HTN, HF
*first line DM with or without microalbuminuria/CKD/CVD/CVD risk factors; non-diabetic CKD; CAD; CVD; HF
MOA: prevents the conversion of angiotensin I to angiotensin II
Dosing: Oral: Initial: 2.5 mg QD; titrate dose based on patient response after 2 to 4 weeks up to 20 mg daily in 1 or 2 divided doses.
Adverse S/E:
Serious
Angioedema (0.2%), cholestatic jaundice, hematologic effects (neutropenia, thrombocytopenia, anemia), hypersensitivity reaction (severe anaphylactoid reaction), hypotension/syncope, renal function deterioration.
Common: HA, dizziness, cough (7-12%), hypotension
Contraindications: hypersensitivity, pregnancy , hx angioedema, bilateral renal artery stenosis
Precautions: electrolyte imbalance, severe renal impairment
Monitoring:
- Obtain serum creatinine and potassium before initiation of therapy, after the first week of therapy, monthly during the first 3 months, and when increasing the dose.
- Liver function tests (LFTs) should be performed prior to initiating therapy.
- For patients with renal impairment assess urine protein prior to initiation, every 2-4 weeks for the first 3 months of therapy, and regularly thereafter for up to 1 year.
WBC count with differential should be monitored prior to initiation of therapy, monthly for the first 3-6 months, and periodically for up to 1 year for patients at risk for neutropenia (renal impairment, collagen vascular disease, high doses).
Hypertension
amlodipine
Generic: amlodipine
Trade:
Classification: CCB
Therapeutic Indication:hypertension,
Amlodipine is especially good for HTN pts with LV dysfunction and CHF
MOA:
Acts from inner side of cell membrane, binds to channels and directly block influx of calcium prolonged smooth muscle relaxation.
Relax arterial smooth muscle, no effect on veins so significantly reduces afterload but limited effect on preload
Negative inotrope (reduce contractility) and decrease SA/AV nodal conduction.
Duration (interval) of treatment:
Adverse S/E:
Hypotension (dizziness, headache, fatigue, syncope), dry mouth, N/V, dry mouth, Photosensitivity and facial telangiectasia, heart failure
Contraindications:
All CCB after MI (esp type 1: negative inotrope, bradycardia), unstable angina
Peripheral edema, ventricular dysfunction
Precautions:CYP3A4 channel drugs that inhibit CYP450 incl grapefruit juice will free drug level
Monitoring:
LFT before initiating therapy
Interaction: histamine2 blockers, alcohol, NSAIDs
BEER’s Criteria:
Geriatric considerations:initiate on half of usual dose, increase gradually to reduce ADR
