BP and Hypertension Patho Flashcards
What are the 2 major components of BP?
CO and SVR
Short Term BP Regulation
- Need to quickly accommodate BP (may be behavioral, emotional, physiologic)
- Mediated by sympathetic nervous system
- Influences HR and SVR
Long Term BP Regulation
- RAAS system
- Neural/hormonal/renal interaction
- Connected with fluid volume homeostasis
- Influences HR, SV, SVR
RAAS
Renin Angiotensin Aldosterone System
Renin
- Baroreceptors sense decrease in volume or BP so signals kidneys to release renin into the bloodstream
- Renin converts angiotensinogen to angiotensin I in liver
Angiotensin I
- Angiotensin I is converted to angiotensin II in lungs
- Converted by Angiotensin-converting enzyme
Angiotensin II
- Primary player in regulation
- Causes potent vasoconstriction and release of aldosterone
- Vasoconstriction increased PVR which increases BP
Aldosterone
- Causes sodium and water retention
- Retained sodium and water increase blood volume
- Increased blood volume causes increased BP
Long term circulating Angiotensin II
- Long term vasoconstriction
- Long term HTN
- Decreased blood flow to brain may cause stroke
- Decreased blood flow to kidneys causes repeat of this cycle
End Organs and RAAS system
- HTN can cause long term negative effects in end organs: brain, heart, adrenal glands, kidneys, efferent arterioles
- Preventable downstream effects
Hypertension Definition
- Increase in BP
- Most common primary diagnosis in the US
- About 30% of population and increasing, also increasing in global population
- More chronic illness with less infectious disease
Primary HTN
- 90% of cases
- Idiopathic = unknown cause
Secondary HTN
- 10% of cases
- Specific cause
- Examples: ingesting something that causes HTN (salt, meds, supplements, caffeine, food), sleep apnea, pregnancy
- Most of these are preventable causes
Risk Factors for HTN
- Most are Preventable/Modifiable
- Having 2+ risk factors significantly increases your risk for stoke/heart attack/heart disease/etc
- Smoking, diabetes, dislipidemia, overweight/obesity, physical inactivity, unhealthy diet, chronic kidney disease, family history, increased age, low SES, male, sleep apnea, psychosocial stress, race/ethnicity, genetics
Childhood/Adolescent Risk Factors for HTN
- Maternal smoking
- Gestational HTN
- Diet
- Low birth weight followed by rapid growth
- Low SES of mom
- Inadequate calcium in pregnancy
- Breastfeeding reduces risk
HTN Evaluation
- BP
- Cholesterol/Triglycerides
- Blood sugar
- Weight
- Risk factors
HTN Treatment
- Lifestyle modifications!!!!!
- Pharmacology for HR, SVR, SV
4 HTN disorders in Pregnancy
- Preeclampsia/eclampsia
- Chronic HTN
- Chronic HTN with superimposed preeclampsia
- Gestational HTN
Risk Factors for HTN in Pregnancy
- Maternal age
- First pregnancy
- In-vitro fertilization
- Morbid obesity
- Multifetal gestation
- Chronic renal disease
- Chronic HTN
- Family history of preeclampsia
- Diabetes mellitus
- Rheumatoid arthritis
- Lupus
What are the 2 major mechanisms behind preeclampsia
- Placental ischemia: blood not getting to placenta and baby
- Maternal vascular dysfunction: may or may not be related to pregnancy
- Placenta may be abnormal with arterial resistance
- Endothelial dysfunction
- CV and inflammatory changes have systemic effects (kidneys, liver)
Clinical Manifestations of Preeclampsia
- BP over 140/90 on 2 occasions, 4 hours apart
AND - Proteinuria
OR
thrombocytopenia, increased liver enzymes, RUQ pain, elevated serum creatinine, pulmonary edema, visual disturbances/cerebral
S/S of Preeclampsia
- Headache
- Edema
- Weakness
- Clonus
- Hyperreflexia
- Vomiting
- Oliguria
- Jaundice
Diagnosis of Preeclampsia
- History and Physical
- Labs: platelets, proteinuria, liver enzymes
Treatment for Preeclampsia
- Mild: bed rest, fetal monitoring
- Severe: birth, vasodilating drugs, antihypertensive, seizure prophylaxis
