Medi Flashcards
Masked Hypertension
- No Hypertension
- Office/Clinic
- Hypertension
- Home/ABPM Setting
Indications for ABPM
- Suspected White Coat Hypertension
- Suspected Episodic Hypertension
- Hypertension Resistant to Increasing Medication
- Hypotensive Symptoms when taking Antihypertensive Medication
- Determining Blood Pressure Control in Patients known to have substantial white coat effect
- Autonomic Dysfunction
HBPM
Self-recorded BP measurement taken at home or work
Better predictor of CVD risk due to elevated BP
ABPM
Device that takes BP measurements over a 24-48 hour period, usually every 15-20 mins during daytime and every 30-60 mins during sleep
Better predictors of CVD risk due to elevated BP
Hypertension Risk Factors
- Age
- Obesity
- Family Hx
- Race (More common and sever in African-Americans)
- High Sodium Diet
- Excess Alcohol Intake
- Physical Inactivity
- Secondary Causes
- Medications
- Contraceptives
- NSAIDs
- Decongestants
- Antidepressants
- Corticosteroids
- Stimulants
Complications of Hypertension
- Premature Cardiovascular Disease
- Heart Failure
- Left Ventricular Hypertrophy
- Ischemic Stroke
- Intracerebral Hemorrhage
- Chronic Kidney Disease (CKD) and End-Stage Renal Disease
- Life-Threatening Emergency
Diagnosis of Hypertension
- Accurately measure patient’s blood pressure
- Perform focused medical history and physical examination
- Obtain results of routine lab studies
- Testing
- 12-Lead EKG
- Consider CXR
- 10 Year CVD Risk or History of ASCVD
What should consist of a good history w/ hypertension?
- Medications (Including OTC)
- Past Med Hx
- Social Hx
- Family Hx
- Weight Changes
- Dietary Intake of Sodium and Cholesterol
- Exercise Level
- Psychosocial Stressors
- Other Symptoms
What should a physical exam for hypertension consist of?
- Fundoscopic eval of eyes
- Papilledema/hemorrhages
- Palpation of ALL Peripheral Pulses
- Thyroid Exam
- Cardiac Examination
- Murmurs/Extra Heart Sounds
- Listen to Lungs
- Listen for Renal Artery Bruits
- Extremities
- Skin Inspection
- Neurological Exam
Lab Testing/Diagnostics Hypertension
- Fasting Blood Glucose
- CBC
- Urinalysis
- Renal Fx: Creatinine
- BMP or CMP
- Lipid Profile
- TSH/FT4
- EKG
- Other
- Uric Acid, Echocardiogram, Urine Albumin/Cr Ratio
- Obtain Urine Albumin/Cr Ratio in all patients w/ diabetes or chronic kidney disease
Lifestyle Modifications for Treatment of HTN
- Weight Reduction
- Sodium Reduction (<1500 mg/day)
- Healthy Diet (DASH Diet)
- Increase Physical Activity (120-150 min/wk)
- Limited Alcohol Consumption
- Men less than or equal to 2 drinks/d
- Women less than or equal to 1 drink/d
- Avoidance of Cigarette Smoking
- Increase Dietary Potassium (3500-5000 mg/d)
Mechanism of Hypertension
BP = Cardiac Output x Systemic Vascular Resistance
Renin-Angiotensin-Aldosterone System
Medications for HTN
- Thiazide Diuretics
- Long-Acting Calcium Channel Blockers
- ACE Inhibitors
- Angiotensin II Receptor Blockers (ARBs)
Recommended treatment/follow-up for Normal BP
- Promote Optimal Lifestyle Habits
- Reassess in 1 Year
Recommended Treament/Follow-Up for Elevated BP (120-129/<80)
- Nonpharmacologic Therapy
- Reassess in 3-6 Months
Recommened Treatment/Follow-Up for Stage 1 HTN (130-139/80-89)
- Clinical ASCVD or Estimated 10-y CVD Risk > or = 10%?
- If Yes
- Nonpharmacologic Therapy and BP-Lowering Med
- Reassess in 1 Month
- BP Goal Met?
- Yes
- Reassess in 3-6 Months
- No
- Assess and Optomize Adherence to Therapy
- Consider Intensification of Therapy
- Reassess in 1 Month
- Yes
- If No
- Nonpharmacologic Therapy
- Reassess in 3-6 Months
- If Yes
Recommened Treatment/Follow-Up for Stage 2 HTN (>140/90)
- Nonpharmacologic Therapy and BP-Lowering Med
- Reassess in 1 Month
- BP Goal Met?
- Yes
- Reassess in 3-6 Months
- No
- Assess and Optomize Adherence to Therapy
- Consider Intensification of Therapy
- Reassess in 1 Month
- Yes
What is the MOA for Thiazide Diuretics?
Inhibit reabsorption of sodium and chloride mostly in distal tubules
What is the MOA for CCB?
Promote vasodilation by reducing calcium influx into vascular smooth muscle cells by interfering w/ voltage-operated calcium channel
What is the MOA of ACE Inhibitors?
Prevent conversion of angiotensin I to angiotensin II
What is the MOA of ARBs?
Competitively block binding of angiotensin II to AT1 receptors, reducing effects of angiotensin II-induced vasoconstriction, sodium retention, and aldosterone release
What is the MOA for Beta-Blockers?
Antagonize effects of sympathetic nerve stimulation or circulating catecholamines at beta-adrenoceptors
What medication should be used with hypertension and diabetic nephropathy or nondiabetic chronic kidney disease w/ proteinuria?
ACE Inhibitor or ARB
What medication should be used for hypertension in African-Americans?
Thiazide Diuretic or Long-Acting Dihydropyridine CCB
Clinical Clue of Suggestive Secondary HTN
- Severe or Resistant HTN
- 3 Antihypertensive Agents and Not Controlled
- Acute Rise in BP in a pt. w/ previously stable BP
- Age <30 Years in Non-Obese
- Malignant or Accelerated HTN
- Severe HTN w/ Evidence of End-Organ Damage
- Hypertension Associated w/ Electrolyte Disorders
- Hypokalemia and Metabolic Alkalosis
- Onset Before Puberty
Common Causes of Secondary HTN
- Renal Parenchymal Disease
- Renovascular Disease
- Primary Hyperaldosteronism
- Drugs/Alcohol
Uncommon Causes of Secondary Hypertension
- Pheochromocytoma
- Cushing’s Syndrome
- Hyper/Hypothyroidism
- OSA
- Coarctation of Aorta
- Primary Hyperparathyroidism
Hypertension w/ Elevated Serum Cr and/or Abnormal Urinalysis
Primary Kidney Disease
- Suspicion of Secondary Hypertension
- Refractory or Malignant HTN
- Worsened Kidney Function During Treatment of HTN
- Especially w/ ACE Inhibitor or ARB
- Severe HTN and Diffuse Atherosclerosis
- Severe HTN and Unexplained Atrophic or Asymmetric Kidneys
- Severe HTN and Recurrent Episodes of Acute Pulmonary Edema or Refractory HF w/ Impaired Renal Function
- Lateralized Abdominal Bruit
Renal Artery Stenosis
Diagnosis of Renovascular HTN
- Tests
- Duplex Doppler Ultrasonagraphy
- CTA
- MRA
- Labs
- Urinalysis
- CBC
- Serum Electrolytes (BMP, CMP)
- BUN, Cr
Treatment of Renovascular HTN
- Lifestyle Modifications
- Antihypertensive Medication
- Surgery
HTN w/ Hypokalemia
Primary Hyperaldosteronism
When to test for primary aldosteronism
- HTN and Hypokalemia
- Severe or Resistant HTN
- HTN and Adrenal Incidentaloma
- HTN and Family Hx of Early-Onset HTN or Cerbrovascular Accident at Young Age
- HTN and First-Degree Relatives w/ Documented Primary Aldosteronism
Most Common Causes of Hyperaldosteronism
- Bilateral Adrenal Hyperplasia
- APAs - Aldosterone-Producing Adenoma
- Symptoms/Signs
- Muscle Weakness
- Headaches
- HTN
Diagnosis of Primary Hyperaldosteronism
- Plasma Aldosterone-Renin Ratio (PAC/PRA)
- May need to verify w/ other confirmatory tests
- Adrenal CT Scan in ALL pts. w/ PA
- To determine subtype and exclude adrenal carcinoma
How is PAC/PRA ratio measured?
- Performed by ambulatory blood test in morning; random PAC and PRA (or PRC)
- PRA and PRC normally undetectable in primary aldosteronism
- PAC is >15 ng/dL
- PAC/PRA ratio >20
- Drugs that interfere w/ test
- Mineralocorticoid Receptor Antagonist
- Spironolactone and Diuretics Hold for 6 Weeks Before
- ACEI and ARBs Increase PRC
- Hold for 2 Weeks
- Mineralocorticoid Receptor Antagonist
Treatment of Hyperaldosteronism
- Normalize Serum Potassium
- Normalize Blood Pressure
- Consider Surgery
- Unilateral Adrenalectomy
- Spironolactone
Signs and Symptoms of Sleep Apnea
- Headache
- Daytime Somnolence and Fatigue
- Snoring
- Difficulty in Concentration
- Depression
- Persistent Systemic Hypertension
- Life-Threatening Cardiac Arrhythmias
Diagnosis of Sleep Apnea
- Polysomnogram (Sleep Study)
- CPAP
Resistant Paroxysmal HTN w/ headache, sweating, and palpitations
Pheochromocytoma
Diagnosis of Pheochromocytoma
- Plasma Free Metanephrines or Urinary Fractionated Metanephrines
- Further metabolizedf to vanillylmandelic acid (VMA)
Treatment of Pheochromocytoma
- Surgical Removal = Treatment of Choice
- Pre-Op:
- Treat HTN and Volume Contraction
- Alpha blockade to control HTN for 2 weeks prior to Beta Blockade to treat tachycardia
- CCB may be used if beta blocker not tolerated
What are the two main mechanisms of metabolic acidosis?
- Extrarenal processes including increased acid production and accelerated extrarenal loss of HCO3-
- Primary defect in renal acidification w/ no increase in extrarenal H+ production
- Renal input of new HCO3 is insufficient to regenerate HCO3 lost in buffering acid as in distal RTA; or filtered HCO3 is wasted as in proximal RTA
- Cl reabsorbtion is increased resulting in a hyperchloremic metabolic acidosis
Anion Gap Acidosis
Contributed if accumulating acid contains an anion other than chloride
Most common cause of increased anion gap
Metabolic Acidosis
Normal Anion Gap
Normal is 12 (9-13 for Phys) or 3x Albumin
- Most of unmeasured anion is albumin
Anion Gap Acidosis Causes
- Uremia
- L-Lactic Acidosis (Type A)
- D-Lactic Acidosis (Type B)
- Alcoholic & Diabetic Ketoacidosis
- Ethylene Glycol
- Methanol
- Toluene
Anion Gap Acidosis
Gap >30 mEq/L
Most common anions are lactate (Lactic Acidosis)
B-hydroxybutyrate and acetoacetate (Ketoacidosis)
Causes of High Anion Gap
- Metabolic Acidosis
- Lab Error
- Severe Volume Depletion (Hyeperalbuminemia)
- Respiratory Alkalosis
- Metabolic Alkalosis
- Severe Hyperphosphatemia
- Increase Anionic Paraproteins (IgA Myeloma)
Type A (L-Lactic Acidosis)
- Due to hypoxia
- Tissue Hypo-perfusion (cardiac failure)
- COPD
- Severe Anemia
- Carbon Monoxide
Type B (D-Lactic Acidosis)
- Liver and Renal Failure
- Cancer
- Exercise
- Seizure
- Thiamine Deficiency
- Metformin
- Alcohol in Malnourished
Causes of Low/Negative Anion Gap
- Lab Error - Most Common
- Hypoalbuminemia - 2nd Most Common
- Mono or Polyclonal Gammopathy
- Bromide, Lithium, Iodide
- Hypercalcemia and Hypermagnesemia
- Low Na w/ SIADH
- Normal Anion Gap
- Low Plasma K
- Low Urine Anion Gap
- Low Urine pH
- Urine PCO2 >70
- FEHCO3 >15%
- High Urine Citrate
- High TTKG
Proximal (Type 2 RTA)
- Normal Anion Gap
- Low Plasma K
- Low Urine Anion Gap
- High Urine pH
- Urine PCO2 <40
- FEHCO3 5-10%
- Low Urine Citrate
- High TTKG
Distal RTA (Type 1 RTA)
- Normal Anion Gap
- High Plasma K
- Very Low Urine Anion Gap
- Low to High Urine pH
- Urine PCO2 <40
- FEHCO3 10-15%
- Low Urine Citrate
- Low TTKG
Generalized Distal Defect RTA (Type 4 RTA)
- Normal Anion Gap
- Low Plasma K
- High Urine Anion Gap
- Low or High Urine pH
- Urine PCO2 >70
- FEHCO3 <5%
- Normal Urine Citrate
- Low TTKG
Extrarenal HCO3 Loss
What distinguishes extrarenal and renal causes of metabolic acidosis?
Urinary Anion Gap
UAG = (UNa + UK) - UCl
Normally is postive 30-50
What does a negative urinary anion gap value suggest?
Increased renal excretion of unmeasured cation such as NH4
(Metabolic Acidosis of Extrarenal Origin is associated w/ increased NH4)
(Acidosis of renal origin is associated w/ positive UAG)
Acute Metabolic Acidosis Shifts the Oxyhemoglobin Curve Which Direction?
- Right
- Faciliates O2 Delivery
- Within a few hours, curve shifts to left
Systemic Effects of Metabolic Acidosis
- Respiratory
- Kussmaul Respirations
- Rapid Response & Complete in 12-24 Hours
- Cardiac
- Depressed contractility
- Vasodilation & Decreased Vascular Resistance
- CNS
- Little in terms of mental status changes
- Bone
- Acute Acidosis - Bone Loss
- Chronic Acidosis - Increased bone dissolution and calcium egress to ECF
- Electrolytes
- Mineral Acid-Induced = Increases K+
- Organic Acid-Induced = No change K
- Increases fraction of ionized calcium → Hypercalcuria
True or False
Metabolic Alkolosis Inhibits Respiration.
True
In Metabolic Alkalosis, how much does pCO2 increase for each 1 mmol/L increase in serum bicarb?
0.7mmHg
Clinical Manifestations of Metabolic Alkalosis
- Hypokalemia
- Hypoxemia due to Hypoventilation
- Weakness
- Neurological Symptoms
- Seizures
- Tetany
- Delirium
- Stupor