HTN Flashcards
What is the trend in systolic and diastolic BP over time?
Systolic: increases
Diastolic: increases, plateaus at 55, then decreases
What are the epidemiological differences in HTN among men and women?
Men: higher prevalence until age 55
Women: after age 64, higher prevalence.
Classification of BP?
Normal: 160/>100 (either/or)
Blood pressure= ???
BP= CO*SVR
SVR=systemic vascular resistance
Mean Arterial Pressure= ???
MAP= DBP+ 1/3 (SBP-DBP)
SVR= ???
SVR= MAP-CVP/CO
Risk Factors for HTN:
Age, tobacco, lower SES, obesity, sedentary lifestyle, psychosocial stressors, dietary factors (Na+ intake), family hx.
What is renin?
hormone released from JG cells in kidney in response to hypoperfusion or activation of SNS. Converts ATogen to AT1.
Influence of AT1 receptors on kidney
intrarenal BP constriction to decr GFR, tubules increase Na+, H2O reabs.
AT1 receptor influence on adrenal gland
cortex incr aldosterone secr, medulla incr catecholamine secr
AT1 receptor influence on vascular smooth musc
growth promoting factors lead to atherogenesis, vasconstriction leads to incr arteriolar resistance.
AT1 receptor influence on CNS
incr adrenal drive incr arteriolar resistance and CO, incr ADH to incr H2O abs, and incr thirst to incr H2O intake.
AT1 receptor influence on myocardium
incr contractibility and hypertrophy, decr collagenase activity.
How do you take an accurate BP measurement?
bare arm, not over clothes, cuff covers 2/3 length of arm, lower edge approx 2.5 cm from antecubital fossa, pt and observer don’t talk.
What is pseudoHTN?
Cuff doesn’t fit correctly (usually too small) that squeezes too much and appears like pt has HTN. Cuff too big–> BP appears lower.
What does a difference in BP b/w the two arms of >15 mmHG indicate?
Subclavian stenosis (lower pressure side)
What is the home pressure measurement to be considered HTN?
> 135/>85
What is the initial evaluation of a pt w/ HTN?
ID possible secondary causes, ID other CVD risk factors, assess for target organ damage.
What is masked HTN?
Normotensive in clinic, HTN outside of clinic.
What is nocturnal HTN?
normotensive in the day, peaks at night, can wake pt w/ chest pain
When do you begin medication regiment for HTN?
Stage 2: mix of medication and behavior change
Stage 1: Varies
Pre-HTN: mostly behavior/diet changes
Classes of anti-HTN drugs
ACE inhibitors, AT receptor blickers, Ca++ channel blockers, Diuretics (AACD), beta-blockers, alpha-blockers, direct vasodilators, aldosterone antagonists, direct renin inhibitors, central alpha-agonists.
2014 HTN tx goal:
FDA Black Box warning for pregnant women
ACE-inhibitors, AT receptor blockers, or renin inhibitors should not be used because of potential for damage for developing fetal kidney.