B4.016 Treatment of Cardiac Arrest Flashcards
treatable causes of non-shockable arrest
Hypoxia Hypovolemia Hydrogen ions (acidosis) Hyper/Hypo-kalemia Hypothermia Tension pneumothorax Tamponade Toxins Thrombosis- cardio Thrombosis- pulm
shockable rhythms
v-fib
pulseless v-tach
most common treatable condition associated w cardiac arrest in a community setting
MI
most common treatable condition associated w cardiac arrest in a hospital setting
PE
major keys for primary prevention of SCA
smoking cessation counseling dietary counseling and modification exercise BP control glycemic control in diabetes lipid lowering therapy
epinephrine indications
VF/pulseless VT
pulseless electrical activity (PEA)/asystole
2nd or 3rd line for symptomatic bradycardia
algorithm for treatment of severe symptomatic bradycardia
treat underlying cause remove offending agents replace electrolytes meds to improve AV conduction: atropine, dopamine, epi temporary pacing
effects of atropine on bradycardia
enhancement of SA and AV nodes via vagolytic effects
SA node: increase discharge
AV conduction: improved conduction
HIs/Purkinje: no effect
mechanism of dopamine
agonism of b1 and b2 receptors
inotropic, chronotropic, and vasoconstrictive effects
effects largely via NE release, which can be depleted in heart failure
WPW pattern
accessory pathway that connect atria to ventricle
faster than conduction through AV nodes
shows as shorter PR segment
what is PVC
premature ventricular complex
ventricular premature depolarization
QRS wider, non-perfusing
why might VT occur in a younger person?
a structurally abnormality
likely due to previous inflammation
what is VT
a rapid collection of PVCs
when is adenosine used?
hemodynamically unstable SVT (while preparing for cardioversion)
hemodynamically stable SVT
indeterminate hemodynamically stable wide complex tachycardia
mechanism of action of adenosine
very transient depression of SA and AV conduction
lifetime risk of developing symptomatic CAD after age 40
49% men
32% women
what is PCI
percutaneous coronary intervention
non-surgical procedure that uses a catheter (a thin flexible tube) to place a small structure called a stent to open up blood vessels in the heart that have been narrowed by plaque buildup, a condition known as atherosclerosis
treatment options for STEMI
primary PCI
fibrinolysis if no PCI immediately available
treatment options for UA/NSTEMI
early conservative: medical management
early invasive: angiography followed by PCI and medical management
characterize the use of fibrolytics in MIs
indicated in acute STEMI
convert plasminogen to plasmin to disrupt fibrin cascade and restore blood flow
1% risk of intracranial bleeding
20-40% failure rate
when is there overwhelming evidence of benefit w use of b-blockers
early use in patients with STEMI in absence of contraindications
contraindications for b blockers
asthma
severe COPD
bradycardia
advanced heart block
should you prophylactically treat arrhythmias after an MI?
no
associated with increased mortality actually
instead look for cause and try to prevent that: electrolyte disturbance, active ischemia, mechanical disruption etc
causes of cardiomyopathy and heart failure
CAD/ ischemic heart disease hypertension valve dysfunction idiopathic/infiltrative cardiomyopathy infections toxins prolonged dysrhythmias
indications for pacemakers
bradydysrhythmias (AV blocks)
may be indicated after initial treatment/stabilization of SCA due to bradydysrhythmias
what are ICDs
implantable cardiac defibrillators
used to treat potentially lethal ventricular dysrhythmias and prevent SCD
primary and secondary indications (for prevention of SCA or after resuscitation of SCA)
most common indications for ICD
primary prevention: HF and perisitently low EF (<35%) despite medical therapy OR hypertrophic cardiomyopathy with high risk for SCA
secondary prevention: resuscitated SCA not associated with acute MI OR hemodynamically significant sustained ventricular tachycardia or v-fib
discuss the results of the MADIT II study
31% reduction in mortality at 20 months in patients given an ICD @ <35% EF with CAD
when should you be mindful of Mg deficiency?
pts with diuretic use, K+ depletion, or alcohol abuse
can induce TdP
characteristics of hypokalemia on EKG
increased amplitude of U waves (after T wave)
characteristics of hypothermia on EKG
J waves present after S waves
