What is the treatment for beta blocker overdose?

Treatment of Beta Blocker Overdose

For beta blocker overdose with refractory shock, high-dose insulin with glucose is the first-line antidote therapy, with typical dosing of 1 U/kg bolus followed by 1 U/kg/hour infusion, coadministered with dextrose and potassium. 1, 2, 3, 4

Initial Stabilization

• Establish cardiac monitoring, secure airway if needed, and obtain IV access as part of standard BLS/ACLS resuscitation 3
• Beta blocker overdose causes life-threatening hypotension and/or bradycardia that is often refractory to standard vasopressor therapy 1, 3
• Do not induce emesis; consider activated charcoal if available and no contraindications exist, but do not delay transport 5

First-Line Pharmacologic Treatment for Refractory Shock

High-Dose Insulin Euglycemia (HIE) Therapy - PRIMARY TREATMENT

The American College of Cardiology gives this a Class 1, Level B-NR recommendation 4

• Dosing protocol: 1 U/kg regular insulin IV bolus, followed by continuous infusion of 1 U/kg/hour, titrated to hemodynamic response 1, 2, 4
• Mandatory coadministration: 0.5 g/kg dextrose bolus, followed by 0.5 g/kg/hour dextrose infusion 4
• Glucose monitoring: Every 15 minutes initially, targeting 100-250 mg/dL 4
• Potassium monitoring: Target 2.5-2.8 mEq/L (moderate hypokalemia is common; aggressive repletion can cause asystole) 4
• HIE improves myocardial inotropy and energy utilization in cardiogenic shock from beta-blocker poisoning 4
• Multiple case series demonstrate mortality benefit and clear hemodynamic improvement 6

IV Glucagon - REASONABLE ALTERNATIVE

The American College of Cardiology gives this a Class 2a, Level C-LD recommendation 1, 2, 3

• Dosing: 3-10 mg IV bolus over 3-5 minutes, followed by 3-5 mg/hour infusion 4
• Case reports and small case series show improvement in bradycardia and hypotension 1
• Glucagon increases contractility and improves hemodynamics 2

Second-Line Therapies

Vasopressors and Inotropes

• Norepinephrine is recommended to increase blood pressure in vasoplegic shock 3
• Epinephrine can be used to increase contractility and heart rate 3
• Catecholamines, vasopressors, and inotropes were associated with reduced mortality in systematic review 6
• Use single or combination catecholamine therapy depending on type of hemodynamic compromise (bradycardia, left ventricular dysfunction, vasodilation) 6

Calcium Administration

The American College of Cardiology gives this a Class 2b, Level C-LD recommendation 1, 3

• Dosing: 0.3 mEq/kg (0.2 mL/kg of 10% calcium chloride) over 5-10 minutes, followed by infusion 4
• Limited animal data and rare case reports suggest possible utility to improve heart rate and hypotension 1
• Three out of six case reports showed hemodynamic improvement, though in association with multiple other therapies 6

Atropine and Pacing

• Atropine may be considered for bradycardia (Class 2b, Level C-LD) 2, 3
• Electrical pacing may be considered for bradycardia (Class 2b, Level C-LD) 2, 3

Rescue Therapy for Pharmacologically Refractory Cases

VA-ECMO (Veno-Arterial Extracorporeal Membrane Oxygenation)

The American College of Cardiology gives this a Class 2a, Level C-LD recommendation for shock refractory to pharmacological therapy 1, 2, 3, 4

• VA-ECMO was associated with improved survival in patients with severe cardiogenic shock or cardiac arrest in observational studies 6
• The American Heart Association consensus statement supports ECMO use for refractory shock from reversible causes such as drug toxicity 1, 3
• Early recognition of the indication for ECMO is one of the most important predictive factors for morbidity and mortality 7
• Ambulance transportation is recommended due to potential for life-threatening complications 5

Hemodialysis for Specific Agents

• Hemodialysis may be considered for potentially life-threatening overdose of water-soluble beta-blockers like atenolol or sotalol (Class 2b, Level C-LD) 2
• Four case reports suggest haemodialysis may assist in massive overdose of specific water-soluble beta-blockers by improving elimination 6

Critical Monitoring and Timing

• Asymptomatic patients should be monitored for at least 6 hours after immediate-release preparations (other than sotalol), 8 hours for sustained-release preparations, and 12 hours for sotalol 5
• Early echocardiography should be obtained to assess myocardial function 4
• Follow-up calls should be made at appropriate intervals for up to 12-24 hours 5

What NOT to Do - Common Pitfalls

• Do NOT use intravenous lipid emulsion (ILE) - The American College of Cardiology explicitly recommends against ILE for beta-blocker poisoning (Class 3: No Benefit, Level C-LD) 2, 4
• Variable and inconsistent response to ILE reported in multiple case series and reports 6
• Do not under-dose insulin - the "high-dose" designation is critical; standard insulin doses will not achieve the desired hemodynamic effect 4
• Avoid dopamine - it is less effective than epinephrine or norepinephrine for hypotension in this setting 4
• Do not abruptly withdraw beta blocker therapy in patients on chronic therapy, as it can lead to clinical deterioration 3

Graduated Treatment Algorithm

For patients with beta blocker overdose and cardiovascular instability:

1. Initial: IV fluids and supportive care 5, 6
2. First-line antidote: High-dose insulin euglycemia therapy (1 U/kg bolus, then 1 U/kg/hour infusion with dextrose/potassium) 1, 2, 4
3. Concurrent: Glucagon (3-10 mg bolus, then 3-5 mg/hour infusion) 2, 4
4. Vasopressor support: Norepinephrine and/or epinephrine as needed 3, 6
5. Consider: Calcium (0.3 mEq/kg over 5-10 minutes) 4
6. Rescue: VA-ECMO for cases unresponsive to pharmacological therapies 1, 4, 6