Hypotension - Exam 1 Flashcards
What is considered hypotension? What is the formula for BP?
BP is <90/60 mmHg
Blood pressure = cardiac output x systemic vascular resistance
Why is hypotension a problem? What is circulatory shock?
extent of the reduction leads to inadequate blood supply to vital organs. This can cause cellular dysfunction and damage.
When oxygen delivery is insufficient to support tissue metabolic requirements
What medication class in particular was mentioned as a possible source of hypotension?
anxiolytics!!
What 3 questions do we need to ask about specifically when working a pt up for hypotension? Name things that should be included in our ROS
Frequent BP changes?
Recent changes in medications?
Pre-existing medical conditions?
Dizziness, lightheadedness, syncope, nausea, confusion, vision changes, fast/shallow breathing, agitation
What are some skin PE findings that would be consistent with hypotension? **What is the major one?
Pallor
Diaphoresis
Prolonged cap refill
**Decreased skin turgor
As long as the pt does NOT have pulm edema, CHF or fluid overload, what is the generic tx for hypotension?
treat the underlying cause!!
fluids with NS
Define orthostatic hypotension. In a normal person, describe what is happening that keeps BP normal.
Described by a significant reduction in blood pressure that typically occurs upon standing or assuming an upright posture.
In a normal patient, baroreceptors in the carotids would detect a positional change causing HR and vascular resistance to rise leading to BP correction and maintenance.
Why is orthostatic hypotension more common in elderly people?
decreased baroreceptor sensitivity
What are some common medication classes that cause hypotension?
When working a pt up for hypotension, what 2 tests need to be done? What is the difference between the 2 tests? _____ also needs to be included in the measurements
orthostatic vitals and/or bedside tilt
passive vs active patient movement
HR/O2 stats
Patients with frequent, very acute changes in BP such as those with suspected baroreceptor insensitivity or vasovagal syncope, consider ______. _______ should also be considered - especially in those with DELAYED symptoms.
continuous BP monitoring
formal tilt test
What is the tilt table testing protocol? How long do they need to remain upright after testing?
Pt will lie down on a special bed or table.
IV line to inject medicine and to give IV fluids, if needed (safety).
ECG electrodes, BP cuff for monitoring (can use Arterial line of needed) and straps across chest and legs
Pt will lie flat on the bed initially, then raised to an almost standing angle while on the bed.
Pt will remain upright for up to 45 minutes to determine if symptoms such as dizziness, fainting, low/high heart rate, or low/high blood pressure occur.
During a tilt table test, the pt does NOT display any symptoms, what happens next?
medication (NTG Sublingual or IV) is given to increase HR.
After the medicine is given (if needed), pt will be tilted upright and monitored for symptoms of dizziness, fainting, low/high heart rate, or low/high blood pressure.
**How much does the BP have to drop in order to be considered orthostatic hypotension?
At least a 20 mmHg fall in SBP
OR/Both
At least a 10 mmHg fall in DBP
Acute orthostasis due to _______
volume depletion
What are the non-pharm tx options for hypotension?
What are the rx options for hypotension? ______ is a common result of the medication. How do you combat it?
Fludrocortisone (Florinef)
Midodrine (ProAmatine)
Supine hypertension
Elevating the head of the bed to 10-20 degrees may protect the brain when sleeping
What is the MOA for Fludrocortisone (Florinef)? What is the monitoring? Why is the medication commonly d/c?
Promotes increased sodium reabsorption and potassium excretion from renal distal tubules
BMP in a week to monitor for hypokalemia
Discontinuation is common due to side effects, predominantly HTN and edema
What is the drug class for Midodrine (ProAmatine)? What is the MOA? What is the MC cause of d/c?
Alpha-1 selective adrenergic agonist
Increases peripheral vascular resistance, which increases arteriolar and venous tone, resulting in increased SBP and DBP
supine hypertension
over ___ patients do NOT find a cause for hypotension. Then what do you do?
1/3
we can consider sending to an autonomic specialist
What does POTS stand for? what is the hallmark response to standing?
Postural Orthostatic Tachycardia Syndrome
exaggerated increase in heart rate
T/F: In order to dx POTS, the pt must have hypotension and exaggerated increase in heart rate upon standing
FALSE!!! do NOT need associated hypotension. common, but not required for diagnosis
What is the MC pt demographic for POTS?
Most common in young patients (14 to 45 yrs)
Much more common in females than males (5:1)
What are 2 very common POTS coexisting conditions?
fibromyalgia and functional GI disorders
What is a common presentation of POTS? What tends to make s/s worse?
Dizziness / Lightheadedness
Syncope
Weakness and fatigue
Blurry vision
cognitive dysfunction (difficulty concentrating, word recall problems, fuzzy, brain fog, difficulty thinking, trouble remembering)
dehydration, menstruation, prolonged standin
**What is the gold standard dx tool and confirmatory tool for POTS?
FORMAL TILT TEST
What is the diagnostic criteria for POTS? What is the requirement for pts under 20 years old? When you do need to record HR and BP?
30+ bpm above a resting supine/seated baseline ALONG WITH PRESENCE OF PATIENT SYMPTOMS and normal/increased BP
40 bpm increase required in patients under 20 years of age ALONG WITH PRESENCE OF PATIENT SYMPTOM
OR
Increase in HR to 120bpm within first 10 mins would also be diagnostic for all patients - symptoms not required here
baseline HR and BP should be measured after at least 5 min of rest supine and again after 1 min of standing.
What is the non-pharm first line tx for POTS?
Avoid any exacerbating factors
Increase water intake (3 liters per day)
Increase salt intake (3 to 5 grams per day)
Aerobic exercise of the lower extremities / compression stockings
What is the pharm tx for POTS? IN ORDER!!!
- Beta blockers - Mostly Propranolol and Metoprolol
- Midodrine
- Fludrocortisone
- Pyridostigmine
One survey of POTS patients found that fludrocortisone improved nausea in half of 16 POTS patients but without significant improvement in _____
orthostatic symptoms
______ enhances sympathetic ganglionic transmission and is given at doses of 30 to 60 mg up to three times daily.
Pyridostigmine
What are the 2nd line pharm agents for POTS?
Ivabradine (awesome drug but expensive)
Methylphenidate
Cardiogenic shock results in end organ _____ secondary to cardiac dysfunction. What is the MC cause of cardiogenic shock? What is the classic pt?
hypoperfusion
extensive cardiac damage and complications from acute MI
evidence of peripheral vasoconstriction (cool, moist skin) and tachycardia
What are some causes of cardiogenic shock?
acute myocardial infarction
end stage cardiomyopathies
myocarditis due to virus, infection, toxin
stress cardiomyopathy
endocrine diseases
secondary to medications (digoxin toxicity)
posttraumatic
Pts with recent or acute MI will have elevated ______. What other lab findings are common?
cardiac-specific enzymes (CK-MB, troponin)
Elevations in serum creatinine and in AST, ALT due to renal and hepatic hypoperfusion
What is the management for a pt with cardiogenic shock?
- Ventilatory support for those who qualify
- Hemodynamic support with inotropic agents or vasopressive agents for patients with severe hypotension
- Aspirin therapy
What are the 2 common vasopressors used in cardiogenic shock? Which one is more common? What does a vasopressor do?
Norepinephrine** MC and dopamine
need to start low and go slow
increases BP
dopamine is more _____ than NE therefore should be given in lower risk patients who have less risk of tachyarrhythmia
inotropic (heart pumps harder)
What are the inotropic agents used in cardiogenic shock? Which one is a beta-1 agonist and PDE-3 inhibitor?
dobutamine: Beta-1 agonist
milrinone: PDE-3 inhibitor
which inotropic agent Increases inotropy AND chronotropy - helps with cardiac function by increasing HR and force of contraction?
dobutamine
which inotropic agent inotropic and lusitropic effects - increases strength of contraction and rate of relaxation?
milrinone
Which inotropic agent is more likely to cause severe hypotension?
Milrinone
