para>It is important to have an open dialogue with patients regarding their Code Status, that is, Do Not Resuscitate (DNR) and/or Do Not Intubate (DNI) orders.
Pediatric Considerations
Asphyxia is the most common precipitant of cardiac arrest in children due to hypoxia and hypercapnia. Impending arrest is often heralded by bradycardia.
Pregnancy Considerations
Left uterine displacement in combination with chest compressions can best be accomplished by placing the patient on a hard surface and manually pulling the uterus to the patient's left and upward. This allows increased blood return to the heart. Consensus guidelines have a standard of 5 minutes for fetal delivery from emergency C-section in those patients unresponsive to CPR (1).
Consider amniotic fluid embolism, eclampsia-related seizures, or flash pulmonary edema as precipitating factors.
EPIDEMIOLOGY
- Predominant age: Risk increases with age.
- Predominant sex: male > female
Incidence
0.5 to 1.5/1,000 persons per year
ETIOLOGY AND PATHOPHYSIOLOGY
- Asystole (confirm in two leads)
- Ventricular fibrillation (VF)
- Pulseless ventricular tachycardia (VT)
- Pulseless electrical activity (PEA)
- Consider possible reversible causes (6 Hs and 5 Ts):
- Hypoxia, hypovolemia, hyper- and hypokalemia, (H+) (acidosis), hypothermia, hypoglycemia
- Cardiac tamponade, tension pneumothorax, thrombosis (pulmonary embolism, myocardial infarction [MI]), toxins (medications and overdoses), trauma
RISK FACTORS
- Male gender
- Advanced age
- Hypercholesterolemia
- Hypertension (HTN)
- Cigarette smoking
- Family history of atherosclerosis
- Diabetes
- Cardiomyopathy
- Prolonged QT
COMMONLY ASSOCIATED CONDITIONS
- Coronary artery disease/acute coronary syndrome (ACS)
- Valvular heart disease
- Pulmonary embolism
DIAGNOSIS
- Absence of pulses in large arteries
- Apnea or agonal breathing
- Loss of consciousness
HISTORY
- Witnessed versus unwitnessed
- Approximate downtime
- Initial resuscitation efforts and response
- History or risk factors
- Associated trauma
- DNR/DNI status
PHYSICAL EXAM
- Feel for pulses
- Asses airway for patency
- Listen for equal, bilateral sounds of lungs to evaluate for respiratory cause of cardiac arrest (pneumothorax, pulmonary edema)
- Nonspecific, but potentially useful findings
- Check for dialysis access (AV fistula/graft or permanent catheter as these patients are at increased risk for hyperkalemia).
- Check pupils: may indicate drug overdose
- Check for obvious signs of trauma.
DIAGNOSTIC TESTS & INTERPRETATION
Initial Tests (lab, imaging)
- Fingerstick glucose
- Arterial blood gas (ABG)/venous blood gas (VBG)
- Chemistry and/or electrolyte panel
- Blood type and cross, if indicated
- Cardiac enzymes (troponin, creatine kinase [CK], CK-MB)
- CBC with platelets
- Drug levels, if indicated (toxicology screen, acetaminophen/aspirin levels, history of specific medication [e.g., digoxin, antiepileptics])
- Perform emergency echocardiogram for pericardial effusion, assessment of cardiac motion, and presence of intraventricular clot.
- Chest x-ray for endotracheal tube (ET) placement, pneumothorax
Diagnostic Procedures/Other
- Obtain access
- Peripheral IV as close to central circulation as possible (preferred)
- Intraosseous (IO) if no venous access
- Consider central venous access if unable to achieve alternative access; femoral approach preferred to minimize interruptions in cardiopulmonary resuscitation (CPR)
- Many medications may be administered by ET if access is otherwise unobtainable (double dose and flush with saline).
- Airway management/intubation
- Needle decompression/chest tube for pneumothorax
- Pericardiocentesis for cardiac tamponade
- ECG
- CT head to evaluate for stroke
- Cardiac catheterization and angiography to assess for coronary disease amenable to percutaneous intervention
TREATMENT
- C-A-B (circulation, airway, breathing). Use compressions first, and then check airway and breathing.
- Prompt initiation of high-quality CPR, particularly chest compressions (at least 100 beats/min, depth 2 inches in adults, allowing recoil after each compression), and immediate defibrillation (in witnessed VF and pulseless VT but not in PEA) are 1st priority (2)[A]:
- In unwitnessed arrest, complete 2 minutes of CPR before attempting defibrillation (3)[A].
- Capnography should be used to evaluate the efficacy of chest compressions (2)[A].
- Avoid excessive ventilation (2)[A].
- Establishing IV access, intubation, and medications are second priority.
- Continue CPR for 1 to 2 minutes following the return of a potentially perfusing rhythm before stopping for a pulse check, except for witnessed arrest with a prompt return of rhythm following defibrillation.
- Patients with a return of spontaneous circulation (ROSC) should have an ECG and be strongly considered for primary coronary intervention. If not available in your facility, then consider transfer to a hospital with this capacity. Early 12-lead ECG may not demonstrate MI, but this may develop late. Intervention should not be delayed in the appropriate setting.
GENERAL MEASURES
- Perform CPR: 100 beats/min, allowing for chest wall recoil, with minimal interruptions (2)
- Sequence should be as follows:
- CPR
- Rhythm check
- Resume CPR
- Shock/medicines (charge defibrillator and administer drugs during CPR)
- Continue CPR (after shocking) for five cycles before rechecking rhythm (repeat as needed) (2).
- In VF/pulseless VT, one shock should be delivered, then continue sequence above (2):
- Monophasic automatic external defibrillators (AEDs) initial and subsequent shocks at 360 J
- Biphasic AEDs
- 150 to 200 J for biphasic truncated exponential waveform
- 120 J for rectilinear biphasic waveform
- If not specified on the biphasic defibrillator, use default of 200 J.
- Subsequent shocks should be the same or higher energy.
- Pediatric manual defibrillation energy should be initial dose of 2 J/kg for the first attempt, followed by 4 J/kg for the next attempt. Increase energy with subsequent attempts but do not exceed 10 J/kg or maximum adult dose.
- Consider possible causes of VT/VF, including hypoxia, hyperkalemia, hypokalemia, preexisting acidosis, drug overdose, and hypothermia.
- Administer 100% oxygen by bag-valve mask or ET.
- IV and IO are the preferred methods of medication administration, followed by ET.
- Start IV lines as close to the heart as possible. Large-bore peripheral lines can deliver fluid more quickly than a triple-lumen catheter.
- Use an end-tidal CO2 (ET-CO2) monitor to assess gas exchange, if available. Capnography is the test of choice to assess ET placement, as esophageal intubation will produce a very low ET-CO2 and requires proper reintubation (2)[A]. The use of sodium bicarbonate will increase ET-CO2 levels.
- Consider a termination of efforts if no reversible underlying cause is found based on the patient's age, comorbid conditions, and length of downtime.
MEDICATION
First Line
- Vascular access for medications: IV or IO
- Consider medications after initiation of CPR and defibrillation attempt; medications should be administered during CPR as soon as possible following a rhythm check.
- Epinephrine (for PEA/asystole/VT/VF): 1 mg IV q3-5min or vasopressin 40 U IV single dose (2)[A] (can be used once in lieu of the first or second dose of epinephrine in VT or VF):
- Pediatric dose of epinephrine: 0.01 mg/kg
- Amiodarone (for VT/VF unresponsive to 2 to 3 shocks and the first dose of vasopressor):
- 300 mg IV push followed by 150 mg IV (2)[B]
- Atropine (for symptomatic bradycardia): dose: 0.5 mg IV every 3 to 5 minutes for maximum of 3 g
- Magnesium sulfate (for suspected torsades de pointes with prolonged QT). dose: 1 to 2 g diluted in 10 mL D5W IV push (2)[C]
- Amiodarone (for supraventricular tachycardia): 150 mg over 10 minutes; repeat as needed followed by a maintenance infusion of 1 mg/min for the first 6 hours
- Adenosine: (for supraventricular tachycardia): 6 mg IV push followed by flush. Followed by 12 mg IV push.
Second Line
- Dopamine (for bradycardia): 2 to 10 μg/kg/min IV
- Lidocaine (If amiodarone is unavailable for pulses VT/VF): Initial dose, 1 to 1.5 mg/kg IV; a repeat loading dose of 1 to 1.5 mg/kg can be given at 5- to 10-minute intervals if VT/VF persist to maximum dose of 3 mg/kg, then followed by drip if perfusing rhythm is recovered.
- Procainamide: 30 mg/min IV in refractory VF/VT (maximum dose: 17 mg/kg) is permissible. However, because the time to a useful level by infusion is so long, it is unlikely to be of benefit in cardiac arrest but may be useful in perfusing tachycardias (2)[C].
- Calcium: may be useful in hyperkalemia, ionized hypokalemia secondary to multiple transfusions, and Ca+ channel blocker toxicity; otherwise, no clear benefit is shown.
- High-dose epinephrine: No survival benefit is seen with a high dose (0.1 mg/kg), but it should be considered in exceptional situations, such as β-blocker or calcium channel blocker overdoses.
- Buffers: bicarbonate: not recommended for routine use; potentially helpful in preexisting bicarbonate-responsive acidosis, hyperkalemia, or to correct widened QRS complex for TCA overdose. Dose: 1 mEq/kg IV.
ISSUES FOR REFERRAL
- Consider communication with the medical examiner's office.
- Consider communication with an organ/tissue bank.
ADDITIONAL THERAPIES
- Therapeutic hypothermia after resuscitation (to 32-34 °C within 6 hours of collapse for 12 to 24 hours) has been demonstrated to improve survival and neurologic function following cardiac arrest (4).
- Extracorporeal cardiopulmonary resuscitation is indicated in pediatric patients with refractory cardiac arrest. In adults, small studies have demonstrated an increase in survival to hospital discharge rates in comparison to conventional CPR following cardiac arrest. However, these results are difficult to reproduce in large, randomized populations and its high costs limit application (5).
ONGOING CARE
FOLLOW-UP RECOMMENDATIONS
Patient Monitoring
- Admit to ICU or coronary care unit (CCU) on continuous monitoring.
- Consider electroencephalogram (EEG) to assess for nonconvulsive status epilepticus.
PROGNOSIS
- The outcome is related to underlying disease, age, duration of arrest, and other factors.
- The outcome is poor with the following indicators:
- >4 minutes to CPR or >8 minutes to ACLS
- Arrest occurs out of hospital
- Resuscitation effort >30 minutes
- ~17% survive in-hospital arrest
- ~1-10% survive to leave the hospital in out-of-hospital arrest, varying by geographic region.
- ~10-15% of those with VF survive
- If the arrest is out of hospital without a return of vital signs from advanced life support (ALS) prehospital care, the patient is unlikely to respond to emergency department (ED) resuscitation efforts.
- If the patient has an ROSC with coma, strongly consider induced hypothermia to improve the neurologic outcome (number needed to treat in VF = 6).
COMPLICATIONS
- Significant neurologic, hepatic, renal, or cardiac ischemic injury or multiorgan systems failure
- Rib fractures, hemopneumothorax, abdominal organ injury from CPR
REFERENCES
11 Lipman S, Cohen S, Einav S, et al. The Society for Obstetric Anesthesia and Perinatology consensus statement on the management of cardiac arrest in pregnancy. Anesth Analg. 2014;118(5):1003-1016.22 Neumar RW, Otto CW, Link MS, et al. Part 8: adult advanced cardiovascular life support: 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation. 2010;122(18)(Suppl 3):S729-S767.33 Stiell IG, Nichol G, Leroux BG, et al. Early versus later rhythm analysis in patients with out-of-hospital cardiac arrest. N Engl J Med. 2011;365(9):787-797.44 Hypothermia after Cardiac Arrest Study Group. Mild therapeutic hypothermia to improve the neurologic outcome after cardiac arrest. N Engl J Med. 2002;346(8):549-556.55 Massetti M, Gaudino M, De Paulis S, et al. Extracorporeal membrane oxygenation for resuscitation and cardiac arrest management. Heart Fail Clin. 2014;10(1)(Suppl):S85-S93.
ADDITIONAL READING
- Holzer M. Targeted temperature management for comatose survivors of cardiac arrest. N Engl J Med. 2010;363(13):1256-1264.
- Wik L, Hansen TB, Fylling F, et al. Delaying defibrillation to give basic cardiopulmonary resuscitation to patients with out-of-hospital ventricular fibrillation: a randomized trial. JAMA. 2003;289(11):1389-1395.
SEE ALSO
Algorithm: Chest Pain/Acute Coronary Syndrome
CODES
ICD10
- I46.9 Cardiac arrest, cause unspecified
- I46.2 Cardiac arrest due to underlying cardiac condition
- I46.8 Cardiac arrest due to other underlying condition
ICD9
427.5 Cardiac arrest
SNOMED
- cardiac arrest (disorder)
- cardiac arrest due to cardiac disorder (disorder)
- Asystole (disorder)
CLINICAL PEARLS
- C-A-B replaces ABCs for the priority of approach to a patient with a suspected cardiac arrest.
- Prompt initiation of CPR, particularly chest compressions (push hard, push fast, and don't interrupt!), and immediate defibrillation (in witnessed VF and pulseless VT but not in PEA) are first priority.
- For an unwitnessed arrest, complete 2 minutes of CPR before attempting defibrillation.
- Epinephrine is the first drug to give in any case requiring CPR: IO and endotracheal routes are preferred if peripheral access is not attainable. Central line may be considered if unable to achieve access and if performed, femoral approach is preferred.
- Most drugs given for cardiac arrest are dosed as 1 ampule (exception: amiodarone loading dose is times — 150 mg ampules)
- Endotracheal medications (NAVEL): naloxone, atropine, vasopressin (and Valium), epinephrine, or lidocaine. Each may be placed in 5 to 10 mL of normal saline or sterile water and given by ET followed by bagging. Dosage should be 2 to 2.5 times recommended IV dose. IV or IO is preferred.
- Therapeutic hypothermia has significantly improved neurologic outcomes in cardiac arrest and should be initiated as soon as possible in any patient with ROSC and coma state.