Critical Care: Test One: Meds, EKG Flashcards
What is the infusion rate formula (based on patient weight)?
? ml/hr = mcg/kg/min ❎ kg ❎ 60
mcg/mL
Half-life of Nitroglycerin?
about 3-5 mins
Infusion rate (NOT based on patient weight):
? mL/hr = mg/min * 60
mg/mL
OR
? mL/hr = mcg/min * 60
mcg/mL
How often do you change IV tubing?
q72hours or by hospital policy
When do you get a new IV bag ready (while another one is currently running)?
When the current bag is at 50-100 mL
What is a side effect of long-term Heparin use?
Osteoporosis.
What is the half-life of Heparin?
about 1.5 hours
What is the antidote to Heparin?
Protamine Sulfate
What is the antidote to warfarin (Coumadin)?
Vitamin K
What is a normal INR?
2-3 usually
What do you monitor with Heparin?
PTT
What do you monitor with Coumadin (warfarin)?
PT/INR
How often do you monitor aPTT with Heparin?
q6h
How often is PT/INR monitored with Coumadin therapy?
Often monitored daily.
How is the INR calculated?
Lab calculates it by dividing patient’s PT by mean PT of individuals not on anticoagulant therapy. INR of 2-3 is therapeutic.
A substance which affects myocardial contractility =
Inotropic (positive=increased force of contraction; negative=decreased force)
A substance which affects Heart Rate =
Chronotropic (positive=increases HR; negative=decreases HR)
Where are alpha 1 receptors located?
vascular smooth muscle
Stimulation of the alpha 1 receptors results in what?
Profuse, body-wide VasoCONSTRICTION (Raises BP)
Alpha 2 receptors are located where?
centrally and peripherally (peripherally is non-signigficant)
Stimulation of alpha 2 receptors causes what?
Centrally located: removal of norep at the neuronal synaptic junctions leading to HYPOTENSION from VASODILATION. SEDATION.
Peripherally: non-significant platelet aggregation action (most meds stimulate a-2 peripherally).
Where are Beta 1 receptors located and what does their stimulation cause?
The heart; increased HR, conduction, and contractility (Pos. Inotropic & Chronotropic)
Where are Beta 2 receptors located and what does their stimulation cause?
- Smooth muscle of the bronchi and the skeletal blood vessels
- Stimulation results in:
- DILATION of the bronchi
- Activation of glycogenolysis (conversion of glycogen to glucose within the liver)=RAISES BLOOD SUGAR
- Uterine CONTRACTIONS
Albuterol is what class of drug?
Beta 2 Agonist
Where are dopaminergic receptors located?
In the coronary arteries, renal, mesenteric and visceral BV’s
You can’t give a negative chronotropic med with a HR less than ____
60
With Inotropic meds, you have to use caution in patients with _____
any heart problems.
Epinephrine stimulates what receptors?
Alpha 1, alpha 2 (peripherally), beta 1, and beta 2
Epinephrine causes vaso_______ except may cause vaso______ in the arterioles of the liver and skeletal muscles (which means increased O2/blood flow.
vasoconstriction; vasodilation
4 Uses for Epinephrine:
Severe Hypotension
Anaphylactic Shock/bronchodilation
In conjunction with local anesthetics
Mydriasis
SE/AR of Epinephrine:
Hypertensive Crisis
Cardiac dysrhythmias/Tachydysrhythmias
Angina Pectoris: Common reason taken off epinephrine
Hyperglycemia
S/s of Hypertensive Crisis:
*Headache (in unconscious person, check behavior–crying, furrow brow, agitation)
*Vision Changes (photosensitivity, diplopia)
*N/V
Change in LOC
Which receptors does Norepinephrine (Levophed) stimulate?
Alpha 1, Alpha 2 (peripherally), and Beta 1; Does NOT stimulate Beta 2=doesn’t raise blood sugar like epi can)
What type of checks are important for a person on Norepinephrine (Levophed) for a “long time” (ie 4 hours) and why?
Circulation checks because it causes profuse vasoconstriction and can lead to amputation. Aka “Leave em’ Dead” (Levophed)
What is Norepinephrine (Levophed) used for?
- Similar to epi, but does not activate Beta 2=NOT used for rescue inhaler
- Utilized with Cardiac Arrest, AV Block
- Most specifically used with HYPOTENSION or DEC. ORGAN PERFUSION
What would you do if you saw signs of decreased circulation with someone taking Norepinephrine?
Don’t turn off IV right away, but call MD ASAP
______ is often a first line drug to raise BP.
Norepinephrine
Epinephrine and Norepinephrine both stimulate the same receptors except Norepinephrine does NOT stimulate _____
Beta 2 (therefore, it doesn’t cause dilation of the bronchi (not rescue inhaler, like epi) or cause blood sugar to increase).
_____ is often a 3rd choice to raise BP.
Vasopressin
Which BP drug is not used for long periods, and is often “Last one on, First one off”?
Vasopressin
What are the uses for Vasopressin?
- Alternative or adjunct pressor to epinephrine in the tx of adult shock, refractory VF/VT
- To enhance CPR (Vasopressin-induced vasoconstriction with CPR increases blood flow to the heart/brain; improves neurological outcome (if CPR is successful))–limited studies on this so far
Which drug do you have to be careful with because it may provoke cardiac ischemia due to its potent peripheral vasoconstriction?
Vasopressin
Drug that may be used to enhance CPR because its vasoconstriction increases blood flow to the heart and brain and thus may improve neurological outcomes (if CPR is successful)?
Vasopressin
What are the 3 levels of dosages for Dopamine and which receptors does each stimulate?
LOW DOSE: 0.5mcg-2mcg; Stimulates dopaminergic receptors in kidneys causing vasodilation=inc. circ & U.O. (however, urine is not filtered in the same capacity so toxicity is possible). Don’t really use low-doses anymore.
MODERATE DOSAGE: 2-10 mcg; Mostly Beta 1= Inc. Contractility/HR/CO
HIGH DOSAGE: >10mcg; Most common; Some Beta 1 until about 15 mcg, then strictly alpha 1 from that point on; Can be third line drug to increase BP.
What is Moderate-dose Dopamine used for?
Symptomatic bradycardia after Atropine failure
What is high-dose Dopamine used for?
Hypotension with s/s of shock, usually in conjunction with epi or norepi
What drugs if taken with Dopamine, will potentiate its effects?
MAO Inhibitors
What are some precautions with Dopamine?
- Tachyarrthythmias
- If hypovolemic, replace volume first
- Do NOT mix with Sodium Bicarb
- Use with caution with cardiogenic shock
- MAO Inhibitors potentiate effects
A direct-acting sympathomimetic with strong alpha 1 adrenergic properties =
Phenylephrine (Neo-Synephrine)
Uses for Phenylephrine (Neo-Synephrine)?
- Severe Hypotension, especially related to shock states; may be used in conjunction (like 5th/6th line), or alone.
- Vascular failure with shock
- Nasal Decongestant (used to be used for this)
- May have nearby post-surgery in case of hypotension
What are some precautions with Phenylephrine (Neo-Synephrine)?
- Palpitations
- Tachycardia
- HTN
- Angina
Drug enhances sinus node automaticity and also AV conduction =
Atropine Sulfate
What is Atropine Sulfate used for?
- Symptomatic sinus bradycardia
- Asystole or PEA
What is the usual dosage of Atropine Sulfate?
1 mg! (however, some places say 0.5-1mg); every 3-5 mins; Tracheal admin=2-3mg diluted in 10 mL normal saline
What drug can you give a one-time dose of WITHOUT a written order if the patient is having SYMPTOMATIC bradycardia (ie dec. CO=hypoperfusion=dec. LOC, etc)?
Atropine sulfate
What is the half-life of Adenosine (Adenocard)?
6-10 secs
What is Adenosine (Adenocard) used for?
- First drug for most forms of narrow complex PSVT
- Mostly used for diagnostic purposes to determine underlying rhythm
Name 3 life-threatening heart rhythms:
V-tach, V-fib, Asystole
Which drug slows conduction through the AV node and interrupts the AV nodal reentry pathway?
Adenosine (Adenocard)
SE’s of Adenosine (Adenocard)?
Bradycardia
Chest pain
Ventricular ectopy
Brief periods of asystole
What does Adenosine (Adenocard) do to the Heart Rate?
Slows it.
What class of drugs is Procainamide (Pronestyl)?
1-A anti-dysrhythmic
What drug reduces the automaticity of all pacemakers and slows intra-ventricular conduction?
Procainamide (Pronestyl)
What is Procainamide (Pronestyl) used for?
- PSVT if uncontrolled by adenosine, only if BP is stable
- Stable wide complex tachycardia of unknown origin
- One of most common anti-dysrhythmics
What is Amiodarone (Cordarone) used for?
- Used for multiple PVC’s or V-tach
- 1st line ACLS med with shock refractory VF and pulseless VT
- Wide complex tachycardia of uncertain origin
- Hemodynamically stable VT when cardioversion is ineffective
- Ectopic or multifocal atrial tachycardia with preserved LV function
- Use as adjunct to cardioversion of SVT/PSVT
- Rate control of A-fib or flutter when other therapies are ineffective
Heart Rhythms:
1) with ___, check for pulse
2) with ___, you can shock them.
3) with ____, you cannot shock them.
v-tach; v-fib; asystole
3 Precautions with Amiodarone (Cordarone):
Hypotension
May prolong QT interval
May have negative inotropic effect (decreases contractility)
_____ is an ACLS for V-tach codes
Amiodarone (Cordarone)
Amiodarone ____ the ventricles.
calms
2 common uses of Amiodarone:
Cardiac arrest and wide complex tachycardia
Drug similar to Amiodarone that also calms the ventricles, and is used for PVC’s, SVT, VT, Cardiac arrest, etc?
Lidocaine (Xylocaine)
Drug that decreases automaticity, slows conduction velocity in re-entry pathways, elevates fibrillation threshold, and may decrease energy to reverse VF =
Lidocaine (Xylocaine)
5 Indications for Lidocaine (Xylocaine)?
PVC's Cardiac arrest from VF/VT Stable VT Wide complex tachycardias of uncertain type Wide complex PSVT
What 3 things does Dobutamine (Dobutrex) do?
Vasodilation (lets heart not work as hard)
Increases Contractility (somewhat gently)
Increases Heart Rate
What is Dobutamine (Dobutrex) used for?
Pump problems (HF, Pulmonary congestion) with SBP of 70-100 and no signs of shock
_______ (drug) increases HR, but is gentler than epi, norepi, dopamine, etc.
Dobutamine (Dobutrex)
What class of drug is Nesiritide (Natrecor)?
Human B-type Natriuretic Peptide (hBNP)
What is the mechanism of action for Nesiritide (Natrecor)?
Increases urine Na+ loss (pulls fluid off body (water follows Na+))
Cardiac smooth muscle relaxation
Vasodilation
What are the uses for Nesiritide (Natrecor)?
Decompensating HF patients
HF/AMI pt’s showing dyspnea at rest or with little exertion
Which drug for HF is even gentler than Dobutamine (Dobutrex)?
Nesiritide (Natrecor)
What are two precautions for Nesiritide (Natrecor)?
SBP <90; cardiogenic shock
What is the mechanism of action for Nitroglycerin (Nitrostat)?
Relaxes vascular smooth muscle and decreases preload
What are the indications for Nitroglycerin?
Chest pain
Peri-operative HTN control
3 Precautions for Nitroglycerin:
Do NOT administer if BP <90
RV infarction
Viagra within 24 hours (causes significant hypotension)
Which drug should not be given if the patient has received Viagra within 24 hours?
Nitroglycerin
We don’t give Nitroglycerin with ____-sided infarct (MI).
Right
If someone is one a Nitroglycerin drip, monitor BP every ___
5 mins
Half-life of Nitroglycerin:
about 3-5 mins
With ____, there is no max dose. However, if systolic reaches ____, you need to titrate them off of it.
Nitroglycerin; 90
What is the fastest known anti-hypertensive?
Sodium nitroprusside (Nipride)
What levels do you have to check with sodium nitroprusside (Nipride)?
Cyanide levels
Sodium nitroprusside (Nipride) causes profuse venous and arterial _____
vasodilation