What medications are safe to give an older patient presenting with severe bradycardia (abnormally slow heart rate) and hypotension (low blood pressure) in an Emergency Medical Services (EMS) setting?

Medications for Severe Bradycardia and Hypotension in Older Patients in EMS Setting

Atropine is the first-line medication for older patients presenting with severe bradycardia and hypotension in an EMS setting, administered at 0.5 mg IV every 3-5 minutes to a maximum total dose of 3 mg. 1, 2

First-Line Treatment

• Atropine remains the first-line drug for acute symptomatic bradycardia with hypotension, particularly in older patients 1
• Initial dose should be 0.5 mg IV every 3-5 minutes, with a maximum total dose of 3 mg 1, 2
• Doses less than 0.5 mg should be avoided as they may paradoxically worsen bradycardia due to central vagal stimulation 2
• Atropine administration should not delay implementation of external pacing for patients with poor perfusion 1

Second-Line Treatments

When atropine is ineffective or contraindicated, consider:

• Epinephrine infusion: 2-10 mcg/min IV for patients with symptomatic bradycardia, particularly if associated with hypotension 1, 2

  • Start at the lower end of the dosing range (2-4 mcg/min) in older patients to avoid potential complications 1
  • Monitor closely for adverse effects including excessive hypertension, which may lead to cerebrovascular hemorrhage in elderly patients 3

• Dopamine infusion: 5-20 mcg/kg/min IV 1, 2

  • Particularly useful for hypotension associated with symptomatic bradycardia 1
  • Lower initial doses (5-10 mcg/kg/min) are recommended for older patients 1
  • Monitor for extravasation, which can cause tissue necrosis 4

Special Considerations for Older Patients

• Older patients may be more sensitive to the effects of medications and at higher risk for adverse effects 1
• Use lower initial doses and titrate carefully while monitoring vital signs 1
• Atropine should be used cautiously in the presence of acute coronary ischemia or myocardial infarction, as increased heart rate may worsen ischemia or increase infarction size 1
• Epinephrine carries increased risk of cerebrovascular hemorrhage in elderly patients due to elevated arterial pressure 3

Medications to Avoid

• Beta-blockers and calcium channel blockers (like diltiazem and verapamil) should be avoided as they can worsen bradycardia and hypotension 1
• Verapamil is specifically listed as a potentially inappropriate medication in people ≥75 years with chronic constipation 1
• Electric pacing is not recommended for routine use in cardiac arrest but may be considered for refractory symptomatic bradycardia 1

Treatment Algorithm

1. Assess airway, breathing, circulation, and provide supplemental oxygen if hypoxemic 1
2. Establish IV access and cardiac monitoring 1
3. Determine if bradycardia is causing signs/symptoms of hemodynamic compromise 5
4. If symptomatic:
   • Administer atropine 0.5 mg IV every 3-5 minutes (max 3 mg) 1, 2
   • If no response to atropine:
     • Initiate epinephrine infusion (2-10 mcg/min) 1, 2 OR
     • Initiate dopamine infusion (5-20 mcg/kg/min) 1, 2
   • Consider transcutaneous pacing if medications fail 1, 2

Pitfalls to Avoid

• Using doses of atropine less than 0.5 mg, which may worsen bradycardia 2
• Delaying transcutaneous pacing in unstable patients who fail to respond to atropine 5
• Using beta-blockers or calcium channel blockers which can worsen bradycardia 1
• Failing to consider underlying causes of bradycardia and hypotension (e.g., medication effects, inferior myocardial infarction) 5
• Administering excessive doses of epinephrine in older patients, which may lead to cerebrovascular hemorrhage 3