What medications can be used to increase heart rate and blood pressure in cases of bradycardia and hypotension?

Medications for Increasing Heart Rate and Blood Pressure in Bradycardia and Hypotension

For patients with bradycardia and hypotension, atropine is the first-line medication, followed by epinephrine or dopamine infusions if atropine is ineffective. In specific cases, phenylephrine may be used for hypotension when tachycardia should be avoided. 1

First-Line Medications

• Atropine: Initial dose 0.5 mg IV every 3-5 minutes to a maximum total dose of 3 mg. This is the first-line treatment for symptomatic bradycardia with hypotension, particularly in older patients. 1
• Caution: Doses less than 0.5 mg may paradoxically worsen bradycardia 1

Second-Line Medications (if atropine ineffective)

• Epinephrine: Infusion at 2-10 mcg/min IV for patients with symptomatic bradycardia and hypotension 1
• Dopamine: Infusion at 5-20 mcg/kg/min IV, particularly useful for hypotension associated with symptomatic bradycardia 1
  • Start with lower doses (5-10 mcg/kg/min) in older patients 1
  • Doses >20 mcg/kg/min may cause vasoconstriction or arrhythmias 2

Alternative Medications for Specific Situations

• Phenylephrine: An alpha-1 adrenergic receptor agonist indicated for increasing blood pressure in adults with clinically important hypotension 3

  • Dosing for perioperative hypotension: IV bolus 50-250 mcg or continuous infusion 0.5-1.4 mcg/kg/minute 3
  • Dosing for vasodilatory shock: IV continuous infusion 0.5-6 mcg/kg/minute 3
  • Useful when tachycardia should be avoided 3

• Glucagon: 3-10 mg IV with infusion of 3-5 mg/h for bradycardia and hypotension due to beta-blocker or calcium channel blocker overdose 2

• High-dose insulin therapy: IV bolus of 1 unit/kg followed by an infusion of 0.5 units/kg/h for beta-blocker or calcium channel blocker overdose 2

• Aminophylline/Theophylline: For specific cases of bradycardia:

  • Post-heart transplant: Aminophylline 6 mg/kg in 100-200 mL of IV fluid over 20-30 min 2
  • Spinal cord injury: Same dosing as above 2

Treatment Algorithm

1. Assess patient stability and severity of symptoms 1

2. For symptomatic bradycardia with hypotension:

   • Administer atropine 0.5 mg IV every 3-5 minutes (max 3 mg) 1
   • If no response to atropine, initiate epinephrine (2-10 mcg/min) or dopamine infusion (5-20 mcg/kg/min) 1
   • Consider temporary pacing if medications fail and patient remains unstable 2

3. For specific causes:

   • Beta-blocker or calcium channel blocker overdose: Consider glucagon or high-dose insulin therapy 2
   • Post-heart transplant or spinal cord injury: Consider aminophylline/theophylline 2

Important Considerations and Pitfalls

• Avoid beta-blockers and calcium channel blockers as they can worsen bradycardia and hypotension 1

• Monitor for adverse effects:

  • Epinephrine and dopamine: Tachyarrhythmias, chest pain 2
  • Phenylephrine: Severe bradycardia and decreased cardiac output 3
  • Atropine: May worsen ischemia in acute coronary syndromes 1

• Pseudoephedrine may be considered in refractory cases of bradycardia and hypotension due to autonomic dysfunction 4

• Don't delay transcutaneous pacing in unstable patients who fail to respond to pharmacological interventions 1