Beta-Blocker toxicity

Question 1

What is the pathophysiology of Beta-Blocker toxicity

Answer 1

1. B blockers competitively inhibit B-1 and B-2 receptors
2. B1 receptor blockage leads to Reduce inotropy, chronotropy and dromotropy.
3. Leads to Hypotension, bradycardia
4. B2 receptor blockage leads to bronchoconstriction, inhibits Glycogenolysis and gluconeogenesis
5. Hypoglycaemia
6. Cardiogenic shock
7. MODS
8. Death

Question 2

What is different about Propanolol compared to other Beta blockers (Toxicity symtpoms)

Answer 2

1. Sodium blocking = Widening QRS and ventricular arrhythmias
2. Lipophilic = CNS depression, seizures and coma

Question 3

What are some Beta blockers present in Australia?

Answer 3

• Atenolol
• Metoprolol
• Isoprolol
• Sotalol
• Propanolol
• nebivolol
• labetalol
• esmolol
• carvedilol
  -Bisoprolol

Question 4

S/S of Beta blocker toxicity

Answer 4

Bradycardia, Hypotension, Pulmonary Oedema, Heart blocks

Question 5

What is the management for Beta-blocker toxicity?

Answer 5

• Normal saline 1L-2L