What is the IV push dose for symptomatic sinus tachycardia?

IV Push Dosing for Symptomatic Sinus Tachycardia

For symptomatic sinus tachycardia, there is no specific IV push medication recommended as first-line therapy, as treatment should primarily focus on identifying and addressing the underlying cause rather than direct rate control. 1

Assessment and Initial Management

• Evaluate for physiologic causes of sinus tachycardia (fever, anemia, hypotension, shock, pain, anxiety, medications, recreational drugs) before initiating specific treatment 1
• Provide supplementary oxygen if the patient shows signs of increased work of breathing or inadequate oxygenation 1
• Establish IV access, attach cardiac monitor, and obtain 12-lead ECG to confirm sinus tachycardia 1
• Determine if the patient is hemodynamically stable or unstable 1

Hemodynamically Unstable Patients

• If the patient demonstrates rate-related cardiovascular compromise with signs of acute altered mental status, ischemic chest discomfort, acute heart failure, hypotension, or shock due to the tachyarrhythmia, proceed to immediate synchronized cardioversion 1
• For synchronized cardioversion of sinus tachycardia (if determined to be the cause of instability), use an initial energy of 50-100 J with biphasic waveform 1
• If the initial shock fails, increase the dose in a stepwise fashion 1

Hemodynamically Stable Patients

First-line approach:

• Identify and treat the underlying cause rather than directly suppressing the sinus node 1
• Important caveat: When cardiac function is poor, cardiac output may be dependent on a rapid heart rate. In such compensatory tachycardias, "normalizing" the heart rate can be detrimental 1

Pharmacological options (if symptomatic and treatment of underlying cause is insufficient):

1. Beta-blockers:

   • Esmolol (IV): 2
     • Loading dose: 500 mcg/kg over 1 minute
     • Initial maintenance: 50 mcg/kg/min for 4 minutes
     • Titrate as needed up to 200 mcg/kg/min
     • Effective maintenance dose range: 50-200 mcg/kg/min
   • Beta blockers are effective for physiological symptomatic sinus tachycardia triggered by emotional stress, anxiety disorders, and post-myocardial infarction 1

2. Non-dihydropyridine calcium channel blockers: 1, 3

   • Diltiazem (IV):
     • Initial: 10 mg slow IV bolus (0.1-0.2 mg/kg ideal body weight)
     • Maintenance: Start at 5-10 mg/hr, titrate up to 30 mg/hr as needed to achieve heart rate <100 beats/min 3
   • Particularly useful when beta blockers are contraindicated or ineffective 1, 3
   • Shown to be effective in achieving heart rate control in 56% of critically ill patients with sinus tachycardia where beta-blockade was contraindicated or ineffective 3

3. Ivabradine: (oral, not IV)

   • While not available as IV push, it's worth noting as an effective agent for ongoing management of inappropriate sinus tachycardia 1, 4, 5, 6
   • Particularly effective when beta blockers are ineffective or poorly tolerated 6

Special Considerations

• For inappropriate sinus tachycardia (IST), which is a persistent increase in resting heart rate unrelated to physiologic demands, beta blockers are considered first-line therapy despite modest efficacy 1, 7
• Avoid rate control medications in compensatory tachycardia where cardiac output depends on the rapid heart rate 1
• When using calcium channel blockers, ensure the absence of ventricular tachycardia or pre-excited atrial fibrillation, as these patients may become hemodynamically unstable if administered diltiazem or verapamil 1
• Avoid calcium channel blockers in patients with suspected systolic heart failure 1

Transition to Oral Therapy

• After achieving adequate control of heart rate and stable clinical status, transition to oral medications should be considered 2
• When transitioning from IV esmolol to alternative drugs, reduce the esmolol infusion by 50% thirty minutes after the first dose of the alternative drug 2
• After the second dose of the alternative agent, monitor response and if satisfactory control is maintained for the first hour, discontinue the esmolol infusion 2