Tachycardia and its ACLS Algorithm
Tachycardia/tachyarrhythmia is defined as a rhythm with a heart rate greater than 100 bpm.
An unstable tachycardia exists when cardiac output is reduced to the point of causing serious signs and symptoms.
Serious signs and symptoms commonly seen with unstable tachycardia are: chest pain, signs of shock, SOA (short of air), altered mental status, weakness, fatigue, and syncope
One important question you may want to ask is: “Are the symptoms being caused by the tachycardia?” If the symptoms are being caused by the tachycardia treat the tachycardia.
There are many causes of both stable and unstable tachycardia and appropriate treatment within the ACLS framework requires identification of causative factors. Before initiating invasive interventions, reversible causes should be identified and treated.
Causes
The most common causes of tachycardia that should be treated outside of the ACLS tachycardia algorithm are dehydration, hypoxia, fever, and sepsis. There may be other contributing causes and review of the H’s and T’s of ACLS should take place as needed.
Administration of OXYGEN and NORMAL SALINE are of primary importance for the treatment of causative factors of sinus tachycardia and should be considered prior to ACLS intervention.
Once these causative factors have been ruled out or treated, invasive treatment using the ACLS tachycardia algorithm should be implemented.
Associated Rhythms
There are several rhythms that are frequently associated with stable and unstable tachycardia these rhythms include:
- Atrial fibrillation
- Atrial flutter
- Supraventricular tachycardia (SVT)
- Monomorphic VT
- Polymorphic VT
- Wide-complex tachycardia of uncertain type
Visit the links above to learn about each specific rhythm.
ACLS Treatment for Tachycardia
Click below to view the tachycardia algorithm diagram. When done click again to close the diagram. Tachycardia Algorithm Diagram.» or Members Download the Hi-Resolution PDF Here
The fist question that should be asked when initiating the ACLS tachycardia algorithm is: “Is the patient stable or unstable?” The answer to this question will determine which path of the tachycardia algorithm is executed.
Unstable Tachycardia
Patients with unstable tachycardia should be treated immediately with synchronized cardioversion. If a pulseless tachycardia is present patients should be treated using the cardiac arrest algorithm.
The initial recommended synchronized cardioversion voltage doses are as follows:
- narrow regular: 50-100 J; i.e., SVT and atrial flutter
- Narrow irregular: 120-200 J biphasic or 200 J monophasic; i.e., atrial fibrillation
- Wide regular: 100 J; i.e., monomorphic VT
- Wide irregular: defibrillation dose (not synchronized)
Patients with stable tachycardia are treated based upon whether they have a narrow or wide QRS complex. The following flow diagram shows the treatment regimen for stable tachycardia with narrow and wide QRS complex.
- Stable (narrow QRS complex) → vagal maneuvers → adenosine (if regular) → beta-blocker/calcium channel blocker → get an expert
- Stable (wide/regular/monomorphic) → adenosine → consider antiarrhythmic infusion → get an expert
abosuyonov says
Hello Jeff.
What’s the treatment for stable polymorphic VT?
Jeff with admin. says
Polymorphic VT will not be stable for long because it most likely will not be providing adequate blood perfusion. The most common treatment for polymorphic VT whether stable or unstable IV magnesium. If unstable provide high energy unsynchronized shock.
Kind regards,
Jeff
Jas says
Hi Jeff, what are the common beta blockers and calcium channel blockers that we can give to patients with narrow qrs complex? And how do we prepare and give the medication? Thanks
Jeff with admin. says
One of the most common IV beta blockers in use today is Labatelol.
One of the most common calcium channel blockers in use today is Cardizem
Kind regards,
Jeff
Jas says
Thanks for the response Jeff. I have another question, Do we give them IV Bolus for tachycardia?
Jeff with admin. says
They can be given IV bolus and they can also be given as an infusion, It just depends upon the situation. If you have a situation where a bolus dose is not keeping the rate under control then a continuous infusion would be implemented to maintain inappropriate heart rate.
Kind regards,
Jeff
Mike Helms says
Is procanimide still used in acls usage
Jeff with admin. says
Yes, procainamide may be used in the treatment of wide complex tachycardia. See Pg. 168 of the AHA ACLS provider manual. This is the AHA guideline statement “Procainamide can be administered at a rate of 20 to 50 mg/min until the arrhythmia is suppressed, hypotension ensues, QRS duration increases >50%, or the maximum dose of 17 mg/kg is given. Maintenance infusion is 1 to 4 mg/min. Procainamide should be avoided in patients with prolonged QT and congestive heart failure.”
Kind regards,
Jeff
jas says
Hi Jeff, How much Diluent do we used For Procainamide and Sotalol infusion For Wide complex Tachycardia? thanks
Jeff with admin. says
Procainamide minimum dilution & dose: 1 g diluted to 50 mL with 5% Dextrose Injection may be administered at 17 mg/kg given with a max rate of 50 mg/min, or 100 mg over 2 minutes every 5 minutes until conversion. (from package insert)
Sotolol minimum dilution: Dilute in NS, D5W, or LR. Prepare in a volume of 100-250 ml. (minimum amt. 100 ml). The recommended initial dose of intravenous sotalol is 75 mg infused over 5 hours, once or twice daily based on creatinine clearance. The dose may be increased in increments of 75 mg/day every 3 days. The usual therapeutic effect is observed with oral doses of 80 to 160 mg once or twice a day (corresponding to 75 to 150 mg intravenous sotalol). Oral doses as high as 240-320 mg once or twice a day (corresponding to 225 to 300 mg intravenous sotalol) have been utilized in patients with refractory life-threatening arrhythmias. (from package insert)
Kind regards,
Jeff
madambac12 says
Another question from american heart association is a 53-year-old woman with has shortness of breath, chest discomfort, and weakness. The patient’s blood pressure is 102/59, the heart rate is 230/min, resp rate is 16 breaths/min. A patent peripheral iv is in place. What is the next action? ( The strip shows svt)
The correct answer is vagal maneuvers. The other answers were procedural sedation which was what I was originally leaning towards since patient might need synchronized cardioversion.
I’m conflicted because the vitals are somewhat stable except for the 230 heart rate, but the clinical signs and symptoms show unstable tachycardia. I somewhat understand the answer because her vitals are stable, but at the same time her clinical picture isn’t. If provided with conflicting information, do you base your decision on vitals or clinical picture? Thank you.
Jeff with admin. says
The only thing in the assessment that would indicate that the patient is unstable are the words “chest discomfort.” Other than that wording, this patient would qualify for vagal maneuvers and then adenosine if vagal maneuvers were unsuccessful. A heart rate of over 200 is typical for SVT and there is a good possibility that vagal maneuvers or adenosine would convert the rhythm to sinis rhythm.
Kind regards,
Jeff
madambac12 says
Thanks for your reply Jeff,
but you had written previously that
“Serious signs and symptoms commonly seen with unstable tachycardia are: chest pain, signs of shock, SOA (short of air), altered mental status, weakness, fatigue, and syncope”
This patient had 3 of these serious symptoms of unstable tach
Jeff with admin. says
I took a look at this scenario again. I saw the respirations of 16. I did not see where it said short of breath the first time. It doesn’t make sense to me why the respirations would be 16 and the patient would be short of breath. Do you expect the respirations to be out of the norm.
Weakness would not typically be associated directly with an unstable condition. To be honest the symptoms (chest discomfort and shortness of breath) make the question a little more difficult to interpret.
If I were them, I would change the symptoms this to make it more clear whether this is a stable or unstable condition.
It is not clear by the scenario whether the patient is truly stable or unstable. I would tend to think that the patient was stable because the blood pressure is stable.
Kind regards,
Jeff
madambac12 says
I was doing the acls preassessment test and came across this question.
A 45 year old woman with a history of palpitations develops light headedness and palpitations. She has received adenosine 6 mg iv for the rhythm (svt) shown here without conversion of the rhythm. She is now extremely apprehensive. Her blood pressure is 128/70 mmhg. What is the next appropriate intervention. ?
The answer is adenosine 12 mg Iv. Can you please explain why. I thought it would be vagal maneuvers since it had a narrow qrs and she seemed stable.
Thanks
Jeff with admin. says
This is a poorly worded question with no history of what was done prior to the administration of the first 6mg of adenosine.
Any attempt at vagal maneuvers should have been attempted prior to the administration of adenosine and this should have been made clear in the question. Vagal maneuvers is attempted before moving to adenosine. This is the order: vagal maneuvers → adenosine 6 mg → adenosine 12 mg. It is not in the AHA guidelines any more but it is still common practice to give a 2nd dose of 12 mg of adenosine if necessary.
Kind regards,
Jeff