Tachycardia algorithm

Question 1

What is the primary treatment of unstable tachycardia?

Answer 1

Immediate cardioversion is recommended.

- Drugs are generally not used

Question 2

Definition and reason for symptoms of unstable unstable tachycardia

Answer 2

Heart rate is too fast > 100bpm
Causes symptoms or unstable condition:
- Heart beating too fast: output is reduced which can cause, pulmonary edema, coronary ischemia, hypotension with reduced perfussion of vital organs
- Heart beating ineffectively so the coordination reduces cardiac output.

Question 3

Signs and symptoms of unstable tachycardia

Answer 3

Hypotension
Acutely AMS
Signs of shock
Ischemic chest discomfort
AHF

Question 4

Causes of sinus tachycardia

Answer 4

Response to extrinsic factors:
- fever
- anemia
- hypotension/shock
- blood loss
- exercise
Sinus tach will not respond to cardioversion, and may increase.

Question 5

Action for atrial flutter with hr > 150

Answer 5

Symptoms are often present

- cardioversion often required

Question 6

Algorithm of tachycardia with a pulse step 1

Answer 6

Assess clinical condition:

- HR typically > or equal to 150 bpm

Question 7

Algorithm of tachycardia with a pulse step 2

Answer 7

Identify and treat underlying cause:

• Maintain airway, assist with breathing
• O2 if hypoxemic
• Cardiac monitor to identify rhythm, BP and O2 sat

Question 8

Algorithm of tachycardia with a pulse step 3

Answer 8

Are there signs of unstable tachycardia
Yes: Step 4: Consider cardioversion
No: Step 5: Is the QRS wide

Question 9

Algorithm of tachycardia with a pulse step 5

- is the QRS wide in the stable tachycardia? Yes

Answer 9

If yes:

• IV access
• ECG if available
• Consider adenosine only if regular and monomorphic (first dose 6 mg rapid IV push; follow with NS flush, 2nd dose 12 mg if required)
• Consider antiarrhythmic infusion
• Consider expert consultation

Question 10

Algorithm of tachycardia with a pulse step 5

- is the QRS wide in the stable tachycardia? No

Answer 10

If no:

• IV access
• ECG if available
• Vagal maneuvers
• Adenosine (if regular)
• B-blocker or CCB
• Consider expert consultation

Question 11

Unstable tachycardia with pulse, regular, wide-complex VT (monophasic): action?

Answer 11

• Treat with synchronized cardioversion an initial shock of 100 J
• If no response to first shock, increase dose in stepwise fashion

Question 12

What is the basic assumption and action if the patient has unstable wide-complex tachycardia

Answer 12

Assume it is VT until proven otherwise

Amount of energy is determined by morphologic characteristics:

Question 13

If polymorphic QRS (polymorphic VT) such as torsades de points: treatment?

Answer 13

Treat as VF:

- high-energy unsynchronized shocks

Question 14

If any doubt if monomorphic or polymorphic VT: treatments?

Answer 14

Do not delay treatment:

- Provide high-energy, unsynchronized shocks

Question 15

Algorithm of tachycardia with a pulse step 4:

Action if tachyarrhthmia is causing symptoms?

Answer 15

Synchronized cardioversion
- Consider sedation
- If regular narrow complex, consider adenosine
(assuming monomorphic VT here I think?)

Question 16

In which conditions should synchronized shocks be given?

Answer 16

• Unstable SVT
• Unstable atrial flutter
• Unstable atrial fibrillation
• Unstable regular monomorphic tachycardia with pulses

Question 17

When to use unsynchronized shocks?

Answer 17

• For a patient who is pulseless
• Clinical deterioration, severe shock or polymorphic VT
• When you feel delay in giving a shock will result in cardiac arrest
• When unsure whether polymorphic or monomorphic VT

Question 18

Energy dose for atrial fibrillation cardioversion?

Answer 18

Monophasic: initial 200 J synchronized shock
Biphasic: initial 120-200 J synchronized shock
- Escalate the second and subsequent shock dose as needed.

Question 19

Energy dose for atrial flutter and SVT cardioversion?

Answer 19

Generally require less than atrial fibrillation

- 50-100 J biphasic or monophasic

Question 20

Energy dose for monomorphic VT (regular form and rate) cardioversion

Answer 20

Initial dose 100J mono or biphasic

- Subsequent shocks increase stepwise

Question 21

What is the treatment for regular narrow-complex tachycardia (except sinus tachycardia)?

Answer 21

Vagal maneuvers and adenosine

Question 22

Features of stable tachycardia

Answer 22

HR greater than 100 bpm
No significant symptoms cause by the increase
Underlying cardiac abnormality that generates the rhythm

Question 23

Most wide-complex tachycardias originate where?

Answer 23

Usually ventricular in origin

Question 24

What is the therapy for narrow QRS with regular rhythm?

Answer 24

Attempt vagal maneuvers

Give adenosine

Question 25

Adenosine contraindications

Answer 25

May cause bronchospasm and generally not given in patients with asthma or COPD