Drugs & Blood Pressure (Clinical) (Dawes) Flashcards
June Smith is a 60 year old woman who visits her doctor with an upper respiratory tract infection.
She is incidentally noted to have a sitting blood pressure of 160/105.
She is a non-smoker and has a BMI of 25. She has no other past medical history of note.
What history and examinations should you ask for/do?
History
- Hypertension (including pregnancy)
- Diabetes
- MI
- High cholesterol
- Stroke
- Medications (HRT, COC, NSAID, OTCs)
- Long term NSAIDs can increase BP
- Diet (sodium intake, pre-processed food, etc.)
- Stress
- Alcohol, smoking
Examination
- Multiple BP (multiple times weekly over the next month)
- WCBP (white coat blood pressure) (phenomenon where patient has hypertension in clinical setting, but not in other settings) (perform BP check at home by herself)
- Cardiovascular examination (heart sounds)
June Smith is a 60 year old woman who visits her doctor with an upper respiratory tract infection.
She is incidentally noted to have a sitting blood pressure of 160/105.
She is a non-smoker and has a BMI of 25. She has no other past medical history of note.
Should You Start Her On Treatment Now?
If You Decide To Start Her On Treatment, Which Medicine Would You Choose And In What Dose?
Should You Start Her On Treatment Now?
- Since her BP is not too high, we don’t need to start treatment immediately, need to see consistency!
- Start on treatment if consistently >160/100mmHg over a number of repeated occasions over a few weeks.
It can be started on (ABCD):
- Thiazide diuretic or calcium channel blocker, but not loop diuretic (very potent (pee a lot), but not as much effect on BP)
-
ACE inhibitor (relatively safe and low side effects)
- Usually only used in “Young” (under 50) patients because ‘young’ patients with hypertension tend to have high renin-activity.
- (might not be effective since older people tend to have low renin hypertension)
- Usually only used in “Young” (under 50) patients because ‘young’ patients with hypertension tend to have high renin-activity.
June Smith is a 55 year old woman who visits her doctor with an upper respiratory tract infection.
She is incidentally noted to have a sitting blood pressure of 160/105.
She is a non-smoker and has a BMI of 25. She has no other past medical history of note.
She is started on treatment with bendrofluazide (a thiazide) 2.5mg once daily.
1) What are some adverse effects?
Potential Adverse Effects of Thiazide
- Hypotension
- Hypokalaemia
- Hyponatraemia
- Hypomagnesaemia
Impaired urate clearance and elevated uric acid level (contraindicated in people with gout)
June Smith is a 55 year old woman who visits her doctor with an upper respiratory tract infection.
She is incidentally noted to have a sitting blood pressure of 160/105.
She is a non-smoker and has a BMI of 25. She has no other past medical history of note.
She is started on treatment with bendrofluazide (a thiazide) 2.5mg once daily.
She tolerates the bendrofluazide without any problems but her blood pressure remains elevated.
How Long Do You Wait Before You Decide To Change Her Treatment?
It takes 2-3 months for thiazide to have full effect.
Not a hurry to change treatment as it is modest hypertension (not too serious).
She is started on treatment with bendrofluazide (a thiazide) 2.5mg once daily.
After a suitable interval, her BP is checked again but is still elevated at 150/100 and you decide to change her treatment.
What are the Advantages And Disadvantages Of Doubling Dose Of Bendrofluazide As Opposed To Adding In A Second Medicine?
With increased dose of thiazide, BP lowering effects plateau at one point while side effects continue to increase with dose (higher dose means more side effects without more benefit of lowering BP).
Aim for synergistic low dose of complementary medications to exhibit maximal BP lowering effects (more advantageous).
She is started on treatment with bendrofluazide (a thiazide) 2.5mg once daily.
After a suitable interval, her BP is checked again but is still elevated at 150/100 and you decide to change her treatment.
You decide to add in a second medicine.
- Which Medicine Do You Choose And In What Dose? What Potential Adverse Effects Do You Have Watch For?
- What Is Your Target Blood Pressure?
Which Medicine Do You Choose And In What Dose? What Potential Adverse Effects Do You Have Watch For?
- We would choose low dose of ACE inhibitor.
- Side effects include
- (1) dry cough;
- (2) hyperkalaemia (monitor serum [K+]) (thiazides lower K+, ACEi increase K+)
What Is Your Target Blood Pressure?
- Target blood pressure would be <140/90mmHg.
She is started on treatment with bendrofluazide (a thiazide) 2.5mg once daily.
After a suitable interval, her BP is checked again but is still elevated at 150/100 and you decide to change her treatment.
You decide to add in a second medicine. (ACEi)
Her blood pressure falls to 130/80 but she can’t tolerate (e.g. cough) the new medicine that you prescribe.
What should you do?
What Do You Do Next?
Change ACEi to angiotensin-II antagonist.
It has similar indications and mechanism of actions, but does not have cough side effects.
Robert Brown is a 65 year old man who is on treatment for hypertension with bendrofluazide 2.5mg once daily but his blood pressure is still 170/95. He has an allergy to peanuts and aspirin.
He is a lifelong smoker and gets wheezy spells during the winter.
He has recently developed chest tightness on exertion that is relieved with glyceryl trinitrate. He has an exercise ECG which confirms the diagnosis of angina.
You decide that he needs additional treatment for his angina.
What are the the Drug Options For Treating Both Hypertension And Angina?
How Do These Medicines Differ In Their Mode Of Action And Adverse Effects?
Which Of These Medicines Do You Choose?
- Calcium channel blocker
- Not dihydropyridines (since they act preferentially on resistance vessels not cardiac tissue)
- Use diltiazem
- Effect in slowing heart rate and decrease inotropy (reduce cardiac work) thus treating angina
- Effect in vasodilation (lowering BP) thus treating hypertension
- Beta-blockers (effect in slowing heart rate and thus reduce work, and effect in lowering BP)
How Do These Medicines Differ In Their Mode Of Action And Adverse Effects?
They have very similar modes of action (both reduce work and reduce BP). However, beta-blockers exacerbate asthma.
- _Wheeze may be asthm_a, which is contraindication to beta-blockers
- Given his age and lifelong smoking history, more likely to be COPD (seasonal wheeziness), which is not a contraindication of beta-blockers.
Which Of These Medicines Do You Choose?
Whichever.
Patients with coronary artery disease typically take beta-blocker + anti-platelet + statin + ACE-I or CCB (if BP remains high)
He is a lifelong smoker and gets wheezy spells during the winter.
He has recently developed chest tightness on exertion that is relieved with glyceryl trinitrate. He has an exercise ECG which confirms the diagnosis of angina.
You decide that he needs additional treatment for his angina.
Additional Cardiovascular Risk Factors Needed To Address?
Additional Cardiovascular Risk Factors Needed To Address
- Lipids (statins)
- Smoker (smoking cessation)
- Lifestyle (exercise regime, diet, smoking)
- Preventative (anti-platelet drugs. e.g. clopidogrel, since he is allergic to aspirin)
He is a lifelong smoker and gets wheezy spells during the winter.
He has recently developed chest tightness on exertion that is relieved with glyceryl trinitrate. He has an exercise ECG which confirms the diagnosis of angina.
You decide that he needs additional treatment for his angina.
He is a lifelong smoker and gets wheezy spells during the winter.
He has recently developed chest tightness on exertion that is relieved with glyceryl trinitrate. He has an exercise ECG which confirms the diagnosis of angina.
You decide that he needs additional treatment for his angina.
How Do You Modify His Treatment?
How Do You Modify His Treatment?
Add an alpha blocker, e.g. doxazosin.
What are the 3 most common causes of HF?
Coronary disease
Valvular disease
Chronic hypertension
(+ alcohol)
70 year old woman ↑ SOBOE for 6 months, waking at night SOB (paroxysmal nocturnal dyspnea)
Never smoked. Previous left hemiparesis 1990s with good recovery. Currently on aspirin and amlodipine.
what is this a sign of?
Heart failure
70 year old woman ↑ SOBOE for 6 months, waking at night SOB (paroxysmal nocturnal dyspnea)
Never smoked. Previous left hemiparesis 1990s with good recovery. Currently on aspirin and amlodipine.
Clinical Examination
- Obese (1.6m, 90kg, BMI 35)
- Raised JVP, oedema to knees
- Pulse 90 irregularly irregular (atrial fibrillation)
- BP 200/80mmHg (seated, large cuff, repeated measure)
Problem List and Potential Diagnosis are….
- Obese (? diabetes)
- Cerebrovascular disease
- Atrial fibrillation (AF)
- Hypertension (SOBOE)
- Cardiomyopathy (?hypertensive) include congestive heart failure (CHF) (SOBOE) due to:
- Paroxysmal nocturnal dyspnoea (PND), which often accompanied with orthopnoea (elevated to get a good night’s sleep, cannot they lie flat during sleep)
- Raised JVP, oedema to knees
- Not lung diseases due to lack of smoking history
Risk factors for AF and CHF include ischaemic heart disease, hypertension, valvular diseases, therefore often occurs together.
70 year old woman ↑ SOBOE for 6 months, waking at night SOB (paroxysmal nocturnal dyspnea)
Never smoked. Previous left hemiparesis 1990s with good recovery. Currently on aspirin and amlodipine.
Clinical Examination
- Obese (1.6m, 90kg, BMI 35)
- Raised JVP, oedema to knees
- Pulse 90 irregularly irregular (atrial fibrillation)
- BP 200/80mmHg (seated, large cuff, repeated measure)
What are Further Investigations for Diagnosis?
- Heart failure (echocardiogram, CXR (>50%), BNP)
- Atrial fibrillation (ECG)
- Hypertension
- End organ damage (renal function, e.g. urea and electrolytes (U+E), urine dipstick (creatinine, proteinuria))
- Blood tests (lipids, glucose)
70 year old woman ↑ SOBOE for 6 months, waking at night SOB (paroxysmal nocturnal dyspnea)
Never smoked. Previous left hemiparesis 1990s with good recovery. Currently on aspirin and amlodipine.
Clinical Examination
- Obese (1.6m, 90kg, BMI 35)
- Raised JVP, oedema to knees
- Pulse 90 irregularly irregular (atrial fibrillation)
- BP 200/80mmHg (seated, large cuff, repeated measure)
What Treatment Options Are Available?
Acute
Acute treatment for fluid overload (one drug at a time, not all three at once):
-
Loop diuretic (e.g. frusemide 40mg) ( decrease JVP and oedema)
- Loop diuretic is potent, so monitor patient weight to check how much fluid is lost (target weight)
- K+ sparing diuretic (mild) (e.g. spironolactone) (improve CHF outcome)
- ACE inhibitor (e.g. cilazapril 5mg) (treat both CHF and hypertension)
In addition, stop amlodipine as it might be contributing to peripheral oedema.
Chronic
- Lifestyle measures such as diet (low sodium), exercise, weight reduction
- Pharmacological measures such as beta-blocker (e.g. metoprolol) (introduce later for long-term)
- Surgical measures such as pacemaker if bradycardia
Other Risk Factors/Co-Morbidities To Address
Address clotting problem with anticoagulation (e.g. warfarin), and address lipid problem with statin.
