Critical Care Pharmacology Flashcards
Vasoconstrictors
-Increases BP
-Increases afterload (some of them less than others)
-Constrict
-Limb ischemias can be affected
-can have more dysrrhythmias
Inotropes
-Increases CO (contractility)
-Can cause more dysthymias
-Elevated lactates
-Can cause hotn/htn
Vasodilators
-Decrease BP
-Dilate
-Decreases Afterload (some more than others)
Complications of vasodilators
-cerebral vasodilation and an increase in intracranial pressure (ICP)
-increased intrapulmonary shunt due to ablation of hypoxic pulmonary vasoconstriction, evidence of platelet dysfunction fromin vitrostudies,
-activation of the sympathetic nervous system with reflex tachycardia, rebound hypertension with discontinuation of its administration
Cardiac Output
-Preload (filling)
-Contractility
-Afterload (resistance to systolic ejection)—effects with htn, valvular stenosis
-SV X HR = CO
Alpha 1
-Constriction on arteries and veins
Alpha 2
-Presynaptic terminal inhibition
Beta 1
-Increased HR, conductivity, automacitity, contractility of the heart
Beta 2
-Bronchodilation of lungs
-Dilation of arterioles
Dopaminergic
-Vasodilation
-effects on the kidney
Corticosteroids
-One of most controversial topics in management of sepsis
-Multiple studies have revealed there’s no benefit or harm
-Don’t need to do stim test just do it
-Rapidly wean over period of days
-When in doubt “stress em out”
-About a week, nice taper
Vitamin C
-Cellular antioxidant
-Cofactor in catecholamine synthesis
-Catecholamine augmentation
-Acute Vit C deficiency common in sepsis
-Hydrocortisone-synergistic with vit c
-thiamine def-reduce hyper-oxalosis risk w/ high dose vit C
Epinephrine Action
-Action on a1, a2, b1, b2 agonist
-1-3mcg/min=B
-3-10 mcg/min=B and a
-10+mcg= a and B
-Increase the HR more as dose increases
-Considered an inotrope = increased contractlity most significantly
-Increases preload
-At 10+ mcg/min will increase SVR & PVR otherwise doesn’t not have much affect on SVR at lower doses
-Increases BP
-Increases CO at lower doses, 10+ mcg/min will decrease CO
Indications for Epinephrine
-Cardiac Arrest
-Anaphylaxis
-Cardiogenic shock
-Bronchospasm
-Reduced CO
-Hypotension
Dopamine Indications
-Low CO
-Low SVR
-Renal insufficiency?
Dopamine Action
-α1, β1, β2, D1 agonist
-Indirect NE release
-1-3μg/kg/min = D1
-3-10 = β1,β2>D1
-10+ = α1>β, D
-Will increase HR at larger doses
-Increases contractality more with increased doses
-Increases preload
-Higher doses will increase SVR and PVR
-CO will increase as well as BP
-2-20 mcg/kg/min infusion
Dobutamine Indications
-Low CO (esp with ↑SVR)
-Right heart failure
-Stress Echocardiography
Dobutamine Action
-Strong β1> β2
-Weak α1
-Increases HR and Contractility and CO
-No affect with preload
-Could increase SVR & PVR in B-blocked patients
-BP varies (generally increases)
- 2-30 mcg/kg/min (never seen it >6mcg/kg/min) infusion
-Considered iontrope
Milrinone Indications
-Low CO (esp with ↑SVR)
-Right heart failure
-Pulm HTN
-Supplement β-agonists
-Reduced proarrhythmic effect
Milrinone Action
-Inhibits Phosphodiesterase III
-Increases cAMP
-Doesn’t act at β receptors
-Increased contractility
-Decreased PVR/SVR
-Increases contractility & CO
-Lowers preload
-Varies with Bp
-0.375-0.75mcg/kg/min
Ca Chloride/Gluconate
-Action: Free Ca Ion
-Increases contractility, SVR/PVR
-Indications: Hypocalcemia, hypokalemia, hotn from hypocalcemia, CCB, or protamine, anesthetic overdose, counter act hypermagnesemia
-1-2g IVP
Phenylephrine Indications
-Peripheral vasodilation
-Low SVR
-SVT (Reflex vagal stim)
-TET spell
-10-150 mcg/min
Phenylephrine Action
-A1 agonist
-Reflex tachycardia
-No difference on contractility, preload and indifference with CO
-Increases SVR/PVR, BP
-10mg/10mL or 100mcg/1mL in codes
Norepinephrine Action
-α1, α2, β1 agonist
-Intense α1 and α2 constriction throughout dosing range
-Variable affect on HR
-Increases contractility, preload, SVR/PVR, BP and medium to CO
Norepinephrine Indications
-Peripheral vascular collapse
-Shock, vasoplegia
-↓SVR
-Need ↑SVR with some ↑Con
-Phenylephrine isn’t working
-2-20 mcg/min some come in mcg/kg/min
Vasopressin Action
-Direct vasoconstriction via V1 receptors
-No action on β or α receptors
-No affect on HR, Contractility, preload
-Variable with CO
-Increases BP
-Increases SVR, decreases PVR?
Vasopressin Indication
-Alt to Epi in Cardiac arrest
-Secondline agent:
Shock, vasoplegia, sepsis,
↓SVR
-Pulm HTN with ↓SVR?
-Physiologic dose with Milrinone
-To reduce Norepi dose
-0.01-0.06U/min
-Bolus 40U IV for VF arrest
Methylene Blue Action
-Complex mechanism
-Inhibits NO/cGMP
-Inhibits NO synthase
-Increases SVR/PVR
-Increases BP
-Not first line
-Bolus 1.5-2.0mg/kg over 15-30 min
-Infusion 0.25-1.0 mg/kg/hr
Nitroglycerin Action
-Direct vasodilator
↑cGMP production
-Venous>Arterial
-Excellent coronary effects
-Reflex contractility and HR
-Decreases Preload (don’t give to inferior MIs)
-Decreases SVR/PVR
-Decreases BP
Nitroglycerin Indication
-Myocardial ischemia
-Increase coronary perfusion
-Relieve coronary spasm
-Hypertension
-Arterial dilation (high dose)
-Pulmonary HTN
-CHF
-40-80 mg IV bolus
-10-200 mcg/min infusion
Nitroprusside Action
-Direct vasodilator
↑cGMP production
-Arterial=Venous
-Reflex effect on HR and Contractility
-Decreases preload, SVR/PVR, BP
Nitroprusside Indications
HTN, ↑SVR
Controlled hypotension
↓SVR>↓Preload at lower dose
-0.1-2.0mcg/kg/min infusion
-Avoid >2.0 d/t toxicity
-protect from light
-use with caution in liver and kidney disease
-Taper infusion gradually
Clevidipine Action
-CCB vasodilator
-No affect on HR, contractility
-Decreases preload, SVR/PVR
Clevidipine Indications
HTN, ↑SVR
Controlled hypotension
↓SVR>↓Preload at lowerdose
-Maintenance: 4-6 mg/hr; not to exceed 21 mg/hr(1000 mL within 24 hour period)
Angiotensin II
-Effective in increases MAP
-Adverse effect monitoring
-Dosing and duration limitation (be careful on running too long)
Hydrococolbalmin (Cyanokit)
-Hydroxylated, active form of vitamin B12
-Nitric oxide scavenger
-FDA approval: treatment of Cyanide poisoning
5 g in 200 mL 0.9% NaCl
-Infusion over 15 minutes or 6 hours
-Suggestive data for utility in refractory vasoplegia
-Remains in bloodstream and urine days to weeks
-Interferes with labs and urinalysis
Alpha 1 Agonists
-Mainly present in smooth muscle of blood vessels and muscle tissues of the heart
-Cause blood vessels to constrict
Shock Management
-Treat underlying cause
-Fluid Resuscitation
-Vasopressor monotherapy»_space;
-Treat w/ contributing pathophysiology
-Combo vasopressor
-Trial steroids, and adjunctive agents (thiamine, vit c)
-Novel vasopressor therapy (Angiotensin II)
-Rescue therapies (Methylene blue, cyanokit)
