Hypotension and Shock Flashcards
Hypotension diagnostic criteria
SBP <90
DBP <60
● May not have any symptoms
● May still have signs/symptoms of hypotension with “normal” BP
● Treat the patient, not the number
Hypotension leads to:
- Reduced cardiac output
- Hypovolemia
- Reduced systemic vascular resistance
- Vascular obstruction
Nonpathologic Causes of Hypotension
Cardiovascular Fitness
Pregnancy
Prolonged bed rest
Alcohol
Presentation of Hypotension
Ranges from mild to severe
● Fatigue
● Dizziness
● Lightheadedness
● Headache
● Fading vision (resolves
with lying down)
● Nausea
● Tachycardia
● Syncope
● Confusion
● Pallor
● Diaphoresis
● Shock
● Seizures
Orthostatic Hypotension
A significant drop in blood pressure after rising from a seated or supine position
Normal blood pressure response to standing:
- Blood pools in lower extremities
- ↓ venous return to heart
- ↓ cardiac output and blood pressure
- Triggers ↑ sympathetic and ↓ parasympathetic stimulation
- ↑ sympathetic outflow raises peripheral vascular resistance, venous return,
and cardiac output - Blood pressure normalizes
Orthostatic Hypotension is caused by failure of _____
compensatory mechanisms
Risk Factors for Orthostatic Hypotension
Baroreflex dysfunction (neurogenic)
Volume depletion
Orthostatic Hypotension presentation
● Generalized weakness
● Dizziness/lightheadedness
● Visual blurring or darkening of the visual fields
● Fatigue
● Cognitive slowing
● Leg buckling
● Headache in suboccipital, posterior cervical, and
shoulder region
● Rarely MI or stroke
Orthostatic Hypotension diagnosis
● Detailed medication list, prescription and
nonprescription
● Recent medical history of potential volume loss
○ Vomiting, diarrhea, fluid restriction, fever?
● Medical history of congestive heart failure,
malignancy, diabetes, alcoholism?
● Neurologic history and examination
Taking Orthostatic blood pressure:
Compare blood pressure in supine and standing positions
1. Have the patient lie down for 5 minutes
2. Measure supine blood pressure and heart rate
3. Have the patient stand up
4. Measure standing blood pressure and heart rate at 1 and 3 minutes
Orthostatic Hypotension =
A reduction of 20 mmHg or more in systolic pressure
A reduction of 10 mmHg or more in diastolic pressure
T/F Heart rate should rise to compensate for postural reduction in blood pressure
T
If HR doesn’t increase, suspect ____
neurogenic orthostatic hypotension
Orthostatic Hypotension labs/diagnosis
● Labs (hematocrit, electrolytes, BUN,
creatinine, glucose, ferritin)
● EKG to r/o underlying heart disease
● Continuous BP monitoring (helpful for
immediate orthostatic hypotension)
● Tilt-table testing (helpful for delayed
orthostatic hypotension)
Orthostatic Hypotension treatment
No specific target BP. Goal is to prevent or reduce symptoms.
● Discontinue or reduce exacerbating
medications
● Increase salt and water intake
● Use compression socks and
abdominal binders
Modify daily activities and lifestyle
Lifestyle modifications for Orthostatic Hypotension
● Stand up slowly, in stages
● Avoid Valsalva-like maneuvers
● Avoid overheating (hot weather,
showers, saunas)
● Tense legs and contract abdominal
and buttock muscles while actively
standing
● Cross legs while standing
● Sleep w/ head of bed elevated
30-45 degrees
● Regular exercise to increase
cardiovascular fitness
Pharmacologic therapy for Orthostatic Hypotension
● Fludrocortisone (1st line)
○ Synthetic mineralocorticoid
○ Increase water and sodium
reabsorption
○ Increases intravascular volume
● Sympathomimetic agents
○ midodrine, droxidopa
● Atomoxetine
● 2nd line
○ Combo of medications
○ venlafaxine
○ pyridostigmine
○ erythropoietin
○ NSAIDs
Orthostatic Hypotension complications
● Falls
● Cardiovascular disease
● Congestive heart failure
● Atrial fibrillation
Vasovagal Hypotension
Neural reflex results in self-limited systemic hypotension characterized by bradycardia
and/or peripheral vasodilation/venodilation
Most common cause of syncope
Vasovagal Hypotension
Vasovagal Hypotension presentation
● Common prodrome: Nausea, pallor,
diaphoresis
○ Caused by increased vagal tone
● Lightheadedness
● A feeling of being warm or cold
● Palpitations
● Fatigue after recovery
Vasovagal Hypotension diagnosis
● In most cases, history and symptoms
are enough to establish diagnosis
● Physical exam usually normal
● BUT EVERYBODY GETS AN EKG
What history information do we need about Vasovagal Hypotension?
● Number, frequency, and duration of episodes
● Associated symptoms preceding syncope
● Patient position at the time of syncope
● Triggers or provocative factors
● Associated symptoms following syncope
● Witnessed signs
● Preexisting medical conditions, medications, and
family history
● Symptoms after recovery
Shock = ____
Hypoperfusion
1. Cardiogenic shock
2. Distributive shock
3. Hypovolemic shock
4. Obstructive shock
Shock S/S
● Pt may appear obtunded or
lethargic
● SBP<90
● Tachycardia
● Confusion
● Pallor
● Decreased urinary output
● Weak peripheral pulses
● Cool, moist extremities
● Metabolic acidosis
Shock diagnosis
● CBC, electrolytes, glucose, ABGs, coagulation panel,
lactic acid, type and cross-match, blood cultures, UA
● EKG
● Chest x ray
● Echocardiogram
Shock treatment
● Depends on the cause
● ABCs
● Fluid resuscitation
● Cardiac monitoring
● Monitor urine output