Asystole
Asystole is defined as the complete absence of cardiac electrical activity. Usually this represents extensive myocardial ischaemia due to prolonged periods of inadequate myocardial perfusion with a very grim prognosis.
1) Determine unresponsiveness, absence of breathing and pulselessness.
2) Maintain an open airway, remove secretions, vomitus, and initiate CPR with supplemental high concentration of oxygen.
3) Continually assess Level of Consciousness, ABCs and Vital Signs.4)Every effort should be made to determine the possible causes of asystole in the patient.Obtain appropriate history related to event, including recent and Past Medical History,Medications, Drug Allergies and Substance Abuse including possible ingestion or overdose of medications, specifically calcium channel blockers, beta-blockers and/or digoxin
preparations.
a) Epinephrine (1:10,000) 1 mg IV push every 3-5 minutes. Epinephrine may be given via Endotracheal Tube if IV not yet established. (2-2.5 mg of Epinephrine 1:1,000 is preferred (ET), every 3-5 minutes)
b) Atropine 1 mg IV push every 3-5 minutes to a total of 0.04 mg/kg. Atropine may be given via Endotracheal Tube if IV not yet established (2.0 mg of Atropine via ETT is preferred; maximum dose 0.08 mg/kg).
c) Sodium Bicarbonate 1 mEq/kg IV Push/if known pre-existing hyperkalemia or known pre-existing bicarbonate-responsive acidosis or if overdose with tricyclic antidepressants.
Atrial Fibrillation
Atrial fibrillation is a totally chaotic activity of the atrial muscle fibers manifested by an irregularly irregular rate. In addition, since the atria are fibrillating, there is incomplete (or non-existent) emptying of these chambers and a loss of as much as 20 per cent of the cardiac output.The rate can be variable, itself a problem, but in addition the loss of the “atrial kick” may, in and of itself, result in hypotension or other signs of cardiovascular compromise.
a) If the patient is hemodynamically unstable, Systolic blood pressure is unstable (less than 90): Synchronized cardioversion at 50 J, 100 J, 200 J, 300J, and 360 J. Check rhythm and pulse between each attempted cardioversion.
b) If Cardioversion is warranted, consider administration of any of the following for sedation:
• Valium: if patient < 70 kg: 2.5 mg SLOW IV Push, if patient > 70 kg: 5.0 mg SLOW IV Push or
• Morphine Sulphate 5 mg – 10 mg SLOW IV Push
To Control a High Ventricular Rate
a) IV beta blocker like Metoprolol 5mg
b) IV Diltiazem HCL (Dilzem)
c)IV Verapamil, unless contraindicated
• Initial bolus: 0.25 mg/kg SLOW IV PUSH over two (2) minutes.
• If inadequate response after 15 minutes, re-bolus 0.35 mg/kg SLOW IV PUSH over two (2) minutes.
• IV Infusion 10-15 mg/hr.
• Note: 5 mg/hr may be appropriate starting infusion for some patients.Contraindications: Wolff-Parkinson-White Syndrome, second or third degree heart block and sick sinus syndrome (except in the presence of a ventricular pace maker),severe hypotension or cardiogenic shock.
• Initial bolus: Verapamil 2.5 mg – 5 mg SLOW IV push. If inadequate response or after 15-30 minutes may re-bolus Verapamil at 5 mg-10 mg slow IV push.
Contraindications: As with Diltiazem aboveBradyarrhythmias
The following can all result in Bradycardia:
Vagal stimulation, intrinsic cardiac conduction system disease, acute myocardial infarction resulting in heart rates from sinus bradycardia to complete, “third degree” heart blocks.If pulse < 60 and patient is symptomatic, place patient supine and elevate legs.
If patient is symptomatic
• Atropine sulfate 0.5 mg to 1.0 mg IV Push or ET every three (3) to five (5) minutes up to total dose 0.04 mg/kg. If administered via ET, 2.0 mg, followed by 2.0 ml of Normal Saline Solution.
• Temporary pacing if indicated.
The following may be ordered:
a) Additional Fluid Boluses of Normal Saline as indicated.
b) Dopamine 5mcg/kg to 20mcg/kg per minute.
c) Epinephrine Infusion (mix 1 mg in 250 cc Normal Saline) Administer 2mcg to 10mcg per minute.
d) Glucagon 1.0 to 5.0 mg IM, SC or IV for suspected beta blocker toxicity.
e) Calcium Chloride 10 per cent 2 - 4 mg/kg IV slowly over five (5) minutes for suspected calcium channel blocker toxicity.
Supraventricular Tachycardia
Supraventricular Tachycardia (SVT) applies to all tachyarrhythmias in which the pacemaker site is originating above the ventricles. Examples of these are Paroxysmal Supraventricular Tachycardia (PSVT), Atrial Fibrillation, Atrial Flutter with a rapid ventricular response, and Junctional Tachycardia with a rapid ventricular response.Generally these groups of tachycardias identify narrow complex rhythm disturbances and should not be confused with Sinus Tachycardia. Narrow complex SVT with heart rates greater than 150/minute requires immediate intervention under most circumstances.
Vagal maneuvers should be started to terminate or modify AV conduction. These consist of the Valsalva manouver, carotid massage, eyeball pressure, induced vomiting, etc.If these fail, IV antiarrhythmic drugs should be used in hemodynamically stable patients. Administer Adenosine 6 mg rapid IV push over 1-3 seconds. If previous 6 mg dose failed to resolve rhythm disturbance. Administer Adenosine 12 mg rapid IV push over 1-3 seconds.Repeat Adenosine 12 mg rapid IV push over 1-3 seconds if previous doses failed to resolve rhythm disturbance.
Note: Follow all Adenosine with a 20 ml normal saline bolus and elevate extremity.
Asystole is defined as the complete absence of cardiac electrical activity. Usually this represents extensive myocardial ischaemia due to prolonged periods of inadequate myocardial perfusion with a very grim prognosis.
1) Determine unresponsiveness, absence of breathing and pulselessness.
2) Maintain an open airway, remove secretions, vomitus, and initiate CPR with supplemental high concentration of oxygen.
3) Continually assess Level of Consciousness, ABCs and Vital Signs.4)Every effort should be made to determine the possible causes of asystole in the patient.Obtain appropriate history related to event, including recent and Past Medical History,Medications, Drug Allergies and Substance Abuse including possible ingestion or overdose of medications, specifically calcium channel blockers, beta-blockers and/or digoxin
preparations.
a) Epinephrine (1:10,000) 1 mg IV push every 3-5 minutes. Epinephrine may be given via Endotracheal Tube if IV not yet established. (2-2.5 mg of Epinephrine 1:1,000 is preferred (ET), every 3-5 minutes)
b) Atropine 1 mg IV push every 3-5 minutes to a total of 0.04 mg/kg. Atropine may be given via Endotracheal Tube if IV not yet established (2.0 mg of Atropine via ETT is preferred; maximum dose 0.08 mg/kg).
c) Sodium Bicarbonate 1 mEq/kg IV Push/if known pre-existing hyperkalemia or known pre-existing bicarbonate-responsive acidosis or if overdose with tricyclic antidepressants.
Atrial Fibrillation
Atrial fibrillation is a totally chaotic activity of the atrial muscle fibers manifested by an irregularly irregular rate. In addition, since the atria are fibrillating, there is incomplete (or non-existent) emptying of these chambers and a loss of as much as 20 per cent of the cardiac output.The rate can be variable, itself a problem, but in addition the loss of the “atrial kick” may, in and of itself, result in hypotension or other signs of cardiovascular compromise.
a) If the patient is hemodynamically unstable, Systolic blood pressure is unstable (less than 90): Synchronized cardioversion at 50 J, 100 J, 200 J, 300J, and 360 J. Check rhythm and pulse between each attempted cardioversion.
b) If Cardioversion is warranted, consider administration of any of the following for sedation:
• Valium: if patient < 70 kg: 2.5 mg SLOW IV Push, if patient > 70 kg: 5.0 mg SLOW IV Push or
• Morphine Sulphate 5 mg – 10 mg SLOW IV Push
To Control a High Ventricular Rate
a) IV beta blocker like Metoprolol 5mg
b) IV Diltiazem HCL (Dilzem)
c)IV Verapamil, unless contraindicated
• Initial bolus: 0.25 mg/kg SLOW IV PUSH over two (2) minutes.
• If inadequate response after 15 minutes, re-bolus 0.35 mg/kg SLOW IV PUSH over two (2) minutes.
• IV Infusion 10-15 mg/hr.
• Note: 5 mg/hr may be appropriate starting infusion for some patients.Contraindications: Wolff-Parkinson-White Syndrome, second or third degree heart block and sick sinus syndrome (except in the presence of a ventricular pace maker),severe hypotension or cardiogenic shock.
• Initial bolus: Verapamil 2.5 mg – 5 mg SLOW IV push. If inadequate response or after 15-30 minutes may re-bolus Verapamil at 5 mg-10 mg slow IV push.
Contraindications: As with Diltiazem aboveBradyarrhythmias
The following can all result in Bradycardia:
Vagal stimulation, intrinsic cardiac conduction system disease, acute myocardial infarction resulting in heart rates from sinus bradycardia to complete, “third degree” heart blocks.If pulse < 60 and patient is symptomatic, place patient supine and elevate legs.
If patient is symptomatic
• Atropine sulfate 0.5 mg to 1.0 mg IV Push or ET every three (3) to five (5) minutes up to total dose 0.04 mg/kg. If administered via ET, 2.0 mg, followed by 2.0 ml of Normal Saline Solution.
• Temporary pacing if indicated.
The following may be ordered:
a) Additional Fluid Boluses of Normal Saline as indicated.
b) Dopamine 5mcg/kg to 20mcg/kg per minute.
c) Epinephrine Infusion (mix 1 mg in 250 cc Normal Saline) Administer 2mcg to 10mcg per minute.
d) Glucagon 1.0 to 5.0 mg IM, SC or IV for suspected beta blocker toxicity.
e) Calcium Chloride 10 per cent 2 - 4 mg/kg IV slowly over five (5) minutes for suspected calcium channel blocker toxicity.
Supraventricular Tachycardia
Supraventricular Tachycardia (SVT) applies to all tachyarrhythmias in which the pacemaker site is originating above the ventricles. Examples of these are Paroxysmal Supraventricular Tachycardia (PSVT), Atrial Fibrillation, Atrial Flutter with a rapid ventricular response, and Junctional Tachycardia with a rapid ventricular response.Generally these groups of tachycardias identify narrow complex rhythm disturbances and should not be confused with Sinus Tachycardia. Narrow complex SVT with heart rates greater than 150/minute requires immediate intervention under most circumstances.
Vagal maneuvers should be started to terminate or modify AV conduction. These consist of the Valsalva manouver, carotid massage, eyeball pressure, induced vomiting, etc.If these fail, IV antiarrhythmic drugs should be used in hemodynamically stable patients. Administer Adenosine 6 mg rapid IV push over 1-3 seconds. If previous 6 mg dose failed to resolve rhythm disturbance. Administer Adenosine 12 mg rapid IV push over 1-3 seconds.Repeat Adenosine 12 mg rapid IV push over 1-3 seconds if previous doses failed to resolve rhythm disturbance.
Note: Follow all Adenosine with a 20 ml normal saline bolus and elevate extremity.
Diltiazem or Verapamil as Under Section on Atrial Fibrillation.
Unstable Patients
Most patients tolerate SVT well, however, some patients may require emergent treatment.Emergent treatment should be administered when the SVT results in an unstable condition. Signs and symptoms may include: angina, shortness of breath, decreased level of consciousness,systolic blood pressure less than 90, shock, pulmonary congestion, and acute myocardial
infarction.
Synchronized cardioversion is done at 50 J, 100 J, 200 J, 300 J, and 360 J. Check rhythm and pulse between each attempted cardioversion.
infarction.
Synchronized cardioversion is done at 50 J, 100 J, 200 J, 300 J, and 360 J. Check rhythm and pulse between each attempted cardioversion.
Ventricular Fibrillation/Pulseless Ventricular Tachycardia
The need for early defibrillation is clear and should have the highest priority.Since these patients will all be in cardiopulmonary arrest, adjunctive equipment should not divert attention or effort from Basic Cardiac Life Support (BCLS) resuscitative measures, early defibrillation and Advanced Cardiac Life Support (ACLS).
Ventricular Tachycardia with Pulses
Ventricular tachycardia represents a grave, life threatening situation in which the patient requires immediate treatment.
The diagnosis is suggested anytime three or more premature ventricular beats occur in succession.With ventricular tachycardia, cardiac output may drop dramatically or be absent altogether and progress into ventricular fibrillation. Ventricular tachycardia, the patient is considered to be either:
1) Pulseless: in essence in Cardiopulmonary Arrest.
2) Stable: presents with pulses, conscious, without chest pain, Systolic blood pressure greater than 90.
3) Unstable: presents with pulses, but is symptomatic: chest pain, palpitations, shortness of breath (SOB), possible signs and symptoms of congestive heart failure (CHF), hypotension(systolic blood pressure less than 90), decreasing level of consciousness (LOC) or unresponsive.
If the patient is haemodynamically stable, consider pharmacological therapy, for example
• Amiodarone IV
• Lignocaine IV
• Some even favour IV sotalol or procainamide
• A class IC agent IV (??)
Comment: There is much controversy about the best drug for VT. Often the best ‘drug’ is in fact electricity, as sustained VT often deteriorates into VF if left unmanaged. Recent literature increasingly favours amiodarone, in a dose of 2.5 to 5mg/kg IV over approximately 10 minutes,although some might argue in favour of higher doses or more rapid administration. Lignocaine is falling into disfavour, and class 1C agents are less-and-less favoured because of their negative inotropic activity.
Modalities
1)DC current, i.e., Electrical Cardioversion.
2) Drugs, i.e, Pharmacological Cardioversion.
3) Anti Tachycardia pacing.
If patient is haemodynamically unstable, perform immediate unsynchronised DC countershock starting at 200 J.
Otherwise, if a patient is at any stage haemodynamically unstable or fails to respond to IV medication, then administer synchronised DC cardioversion, starting at 100 J, then 200 J, then maximum settings.
If synchronisation fails due to bizarre QRS morphology, then switch to asynchronous mode (with the attendant risk of ventricular fibrillation).
The diagnosis is suggested anytime three or more premature ventricular beats occur in succession.With ventricular tachycardia, cardiac output may drop dramatically or be absent altogether and progress into ventricular fibrillation. Ventricular tachycardia, the patient is considered to be either:
1) Pulseless: in essence in Cardiopulmonary Arrest.
2) Stable: presents with pulses, conscious, without chest pain, Systolic blood pressure greater than 90.
3) Unstable: presents with pulses, but is symptomatic: chest pain, palpitations, shortness of breath (SOB), possible signs and symptoms of congestive heart failure (CHF), hypotension(systolic blood pressure less than 90), decreasing level of consciousness (LOC) or unresponsive.
If the patient is haemodynamically stable, consider pharmacological therapy, for example
• Amiodarone IV
• Lignocaine IV
• Some even favour IV sotalol or procainamide
• A class IC agent IV (??)
Comment: There is much controversy about the best drug for VT. Often the best ‘drug’ is in fact electricity, as sustained VT often deteriorates into VF if left unmanaged. Recent literature increasingly favours amiodarone, in a dose of 2.5 to 5mg/kg IV over approximately 10 minutes,although some might argue in favour of higher doses or more rapid administration. Lignocaine is falling into disfavour, and class 1C agents are less-and-less favoured because of their negative inotropic activity.
Modalities
1)DC current, i.e., Electrical Cardioversion.
2) Drugs, i.e, Pharmacological Cardioversion.
3) Anti Tachycardia pacing.
If patient is haemodynamically unstable, perform immediate unsynchronised DC countershock starting at 200 J.
Otherwise, if a patient is at any stage haemodynamically unstable or fails to respond to IV medication, then administer synchronised DC cardioversion, starting at 100 J, then 200 J, then maximum settings.
If synchronisation fails due to bizarre QRS morphology, then switch to asynchronous mode (with the attendant risk of ventricular fibrillation).
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