Cardiac Arrest
Description of Medical Condition
Absence of effective mechanical cardiac activity.
• This section is not a substitute for an American Heart Association approved ACLS course and is intended only as a quick reference
System(s) affected: Cardiovascular
Genetics: N/A
Incidence/Prevalence in USA: 200:100,000
Predominant age: Increases with age
Predominant sex: Male > Female
Medical Symptoms and Signs of Disease
• Unconscious secondary to CNS hypopertusion
• No pulses in large arteries
• Apnea or agonal breathing
• Cyanosis or pallor
What Causes Disease?
• Asystole (confirm in 2 leads; 11 % actually fine V-fib)
• Ventricular fibrillation (V-fib)
• Pulseless ventricular tachycardia (V-tach)
• Pulseless electrical activity (PEA, previously known as electrical mechanical dissociation [EMD])
Risk Factors
• Male
• Increasing age
• Hypercholesterolemia
• Cigarette smoking
• Positive family history of atherosclerosis
Diagnosis of Disease
Differential Diagnosis
• Drugs: barbiturates, narcotics, calcium channel block-ers, beta blockers, tricyclics
• Shock: septic or blood loss induced
• Hypothermia
• Pulmonary embolism
• Cardiac tamponade
• Pneumothorax
• Acidosis
• Electrolyte abnormality
• Carbon monoxide
Laboratory
• Arterial blood gas
• Electrolytes
• CBC
• Drug levels
• PT (international normalized ratio [INR]), PTT, type and cross, if indicated
Drugs that may alter lab results: Digoxin toxicity may cause hyperkalemia
Disorders that may alter lab results:
• Hypo- or hyperventilation will change pO2 and pCO2
• Acidosis increases serum potassium
Pathological Findings
Based on underlying cause
Special Tests
ECG
Imaging
Chest x-ray for endotracheal (ET) tube placement, pneumothorax. Consider echocardiogram for pericardial effusion.
Diagnostic Procedures
N/A
Treatment (Medical Therapy)
Appropriate Health Care
Pre-hospital emergency medical service (EMS) personnel, emergency department, “cardiac arrest team”, intensive care setting
General Measures
• Defoliation first
– Adult: 200, 300, or360J
– Children: Use largest paddles that will fit on child even adult size if can get good contact. Defibrillate at 2J/kg once. Increase to 4J/kg twice.
• 100% oxygen by bag-valve-mask or endotracheal tube (preferred)
• Start 2 IVs as close to the heart as possible (central line OK but don’t waste time). Large bore peripheral lines can deliver fluid more quickly than a central line. This is especially important in PEA secondary to hypovolemia.
• Perform CPR including closed chest compression, ntermittent abdominal compression and active compression/decompression show no survival advantage.
• Keep patient warm if possible, especially in children
• Monitor:
– Pulse after three initial defibrillations
– Check monitor between each defibrillation and after any intervention
– Use end-tidal C02 monitor to assess gas exchange if available. Esophageal intubation will produce a very low end-tidal CO2.
Surgical Measures
If indicated:
• Pericardiocentesis to treat cardiac tamponade
• Needle decompression (second intercostal space mid-clavicular line), then chest tube insertion to treat tension pneumothorax
Activity
N/A
Patient Education
Suggest basic life support (BLS) training to all patients in your practice, especially those who have family members at risk for cardiac arrest
Medications (Drugs, Medicines)
Drug(s) of Choice
• Lidocaine, atropine, naloxone, and epinephrine [LANE] can all be given by endotracheal tube. Follow by 10 cc of NS or sterile water followed by bagging.
• Epinephrine:
01 mL=1 mg (1:1000)
01 mL = 0.1 mg (1:10,000) ADULT: Ventricular tachycardia and pulseless ventricular tachycardia. Use in order listed below:
• Defibrillate x3 at 200J, 300J, 360J
– Check monitor rhythm
– Follow each drug administration by repeated defibrillation at 360J
– Check monitor and pulses after each subsequent intervention
• Epinephrine: 1 mg IVevery 3-5 minutes or vasopres-sin 40U IV single dose, one time only. May choose to resume epinephrine if no response after a single dose of vasopressin. High dose epinephrine is permissible but discouraged and may actually worsen outcomes.
• Amiodarone 300 mg IV push may be used prior to lidocaine
• Lidocaine: 1.5 mg/kg IV, repeat in 5 minutes to total dose of 3 mg/kg
• Magnesium sulfate: 1-2 mg IV in suspected Torsades de pointes or refractory V-fib/V-tach
• Procainamide 30 mg/min IV in refractory V-fib/V-tach (maximum dose of 17 mg/kg) is permissible. However, since the time to a useful level by infusion is so long, it is discouraged and is unlikely to be of any benefit. No improvement in survival to discharge.
• Bicarbonate: 1 mEq/kg IV only in known preexisting bicarbonate responsive acidosis, tricyclic overdose, to alkalinize the urine in known overdose
ADULT: Asystole
•CPR
• Confirm in 2 leads
• Consider possible causes including hypoxia, hyperkalemia, hypokalemia, preexisting acidosis, drug overdose, hypothermia
• Consider defibrillation as per V-tach/V-fib since V-fib may be mistaken for asystole
• Consider immediate transcutaneous pacing
• Epinephrine: 1 mg IV push repeated every 3-5 minutes
– May use intermediate dose or high dose epinephrine
(2-5 mg IV or 0.1 mg/kg IV) every 3-5 minutes
• Atropine: 1 mg IV push every 3-5 minutes to total dose of 0.04 mg/kg
– Shorter atropine dosing intervals are acceptable (every 1-2 minutes)
• Consider termination of efforts if no reversible underlying cause is found
For pulseless electrical activity (PEA)
• Includes EMD, idioventricular rhythms, ventricular escape rhythms, bradyasystole rhythms, post-defibrillation idioventricular rhythms
• Assess blood flow by Doppler ultrasound if available
• Consider possible reversible causes: cardiogenic shock (weak pump), cardiac tamponade, tension pneumothorax, severe hypovolemia, pulmonary embolism (consider thrombolytics), hypothermia, hypoxia, acidosis. hyperkalemia, drug overdose such as beta-blockers. calcium channel blockers, tricyclics, digoxin
• Epinephrine: 1 mg IV push. Repeat every 3-5 minutes. Can use intermediate or high dose epinephrine (2-5 mg IV or 0.1 mg/kg IV respectively) every 3-5 minutes, but this shows no proven improvement in survival.
• Atropine: 1 mg IV every 3-5 minutes to total dose ot 0.04 mg/kg: if absolute bradycardia (< 60 beats per minute) or relative bradycardia. May decrease interval to 1-2 minutes if desired.
CHILDREN:
(in alphabetical order)
• Amiodarone for pulseless VF/VT 5 mg/kg IV or IO rapid bolus. For perfusing tachyarrhythmias loading 5 mg/kg IV or IO over 20-60 minutes, maximum dose 15 mg/kg/d.
• Atropine 0.01-0.02 mg/kg/dose; minimum dose is 0.1 mg, maximum single dose is 0.5 mg in child, 1.0 mg in adolescent
• Epinephrine
– Bradycardia: 0.01 mg/kg IV/IO or0.1 mg/kg ET (1:1000)
– Asystolic or pulseless arrest: First dose is 0.01-0.03 mg/kg IV/IO. Doses as high as 0.2 mg/kg may be effective.
– Infusion: 0.1 kg/kg/min. Titrate to desired effect (0.1 μg/kg/min-1.0μg/kg/min)
• Lidocaine
– Bolus: 1 mg/kg/dose (maximum 3 mg/kg)
– Infusion: 20-50 μg/kg/min
• Sodium bicarbonate 1 mEq/kg/dose or 0.3x kg x base deficit. Infuse slowly and only if ventilation adequate.
Contraindications: None during an arrest
Precautions:
• Calcium can be used if known (pre-existing) hyperkalemia precipitated arrhythmia. Calcium is contraindicated in hyperkalemia secondary to digoxin.
• Magnesium is relatively contraindicated in renal failure but given consequences of not terminating rhythm, this is only a relative contraindication in this setting
Significant possible interactions: N/A
Alternative Drugs
Asystole: Aminophyl-line 250 mg IV bolus has been effective in uncontrolled trials, but should be used only when conventional therapy has failed
Patient Monitoring
Intensive care setting on continuous monitor, look for precipitating cause including serial EKG’s and enzymes to rule out myocardial infarction
Prevention / Avoidance
Treat underly ing disease
Possible Complications
• Can have significant neurologic, hepatic, renal, and cardiac ischemic injury
• May have rib fractures or pneumothorax from CPR
Expected Course / Prognosis
• Outcome related to underlying disease, age, duration ot arrest, etc.
• Outcome poor if
– > 4 minutes to CPR or > 8 minutes to ACLS
– Arrest in field
– Resuscitation effort > 30 minutes
• About 14% survive in-hospital arrest; fewer after field arrest.
Miscellaneous
Associated Conditions
• Coronary artery disease (cardiac arrest may be first presenting symptom)
• Valvular heart disease
Age-Related Factors
Pediatric: Bradycardia is most common initial form of cardiac arrest. Most frequently is primarily a response to underlying pulmonary disease and hypoxia. Adequate oxygenation and ventilation is especially important.
Geriatric: Poor risk for survival and long-term outcome
Pregnancy
• Displace uterus either manually or by placing a rolled towel or pad under right hip. If not able to resuscitate within 5-15 minutes, consider emergency C-section to relieve uterine obstruction and increase blood return to the heart. This may also be done to save the fetus if at a viable age.
• Consider amniotic fluid embolism or eclampsia related seizures as precipitating factors
Synonyms
• Code Blue
International Classification of Diseases
427.5 Cardiac arrest
See Also
Abbreviations
ACLS = Advanced Cardiac Life Support
EMD = electro-mechanical dissociation
ET = endotracheal
IO = intraosseous
PEA = pulseless electrical activity
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