9.7. POISONING/OVERDOSE BY BETA-BLOCKERS

Related titles

Antihypertensive drugs.

Purpose of assistance

1. Weaken the absorption of oral agents in the gastrointestinal tract by using a certain type of binding agent (activated carbon), especially for long-term poisoning.
2. Early maintenance of airway control, as rapid deterioration of consciousness may occur.
3. Ensuring adequate ventilation, oxygenation and correction of hypoperfusion.

Description of the patient

Beta-blockers or beta-adrenergic antagonists weaken the effect of epinephrine/adrenaline.

Inclusion criteria

1. The patient may have:

a) bradycardia;
b) hypotension;
c) altered state of consciousness;
d) weakness;
e) shortness of breath ;
e) convulsions are possible.

2. Examples of beta-blockers:

a) acebutolol hydrochloride;
b) atenolol;
c) betaxolol;
d) bisoprolol fumarate;
e) carteolol hydrochloride;
e) esmolol hydrochloride;
e) metoprolol;
e) nadolol;
g) nebivolol;
h) penbutolol sulfate;
y) pindolol;
i) propranolol;
i) timolol maleate;
i) sotalol hydrochloride.

3. An example of alpha/beta-adrenergic drugs:

a) carvedilol;
b) labetalol.

Exclusion criteria

No recommendations.

Management of the patient

Status assessment

1. Perform a complete initial examination (ABCDE) if indicated, then undress the patient and later cover him for warmth.
2. Assess vital signs, including body temperature.
3. Apply a cardiac monitor, assess for arrhythmias, then record a 12-lead ECG.
4. Check your glucose level.
5. Monitor pulse oximetry and ETSO2 for decompensation.
6. Recognize the specific drug (determine the onset of action – immediate or delayed) – name, time of administration, quantity.
7. Collect history or medications prescribed for the patient.
8. Explore the presence of diseases relevant to this case.
9. Do a physical examination.

Treatment and intervention

1. Administer sorbitol-free activated charcoal (1 g/kg) orally.
At risk of rapid unconsciousness, do not administer tablets without first obtaining airway control.

2. Monitor glucose levels in all patients, especially children, as beta-blockers can cause hypoglycemia in children.

3. Use atropine for symptomatic bradycardia:

a) adults: 1 mg IV every 5 minutes, maximum dose 3 mg;
b) children: 0.02 mg/kg (maximum dose – 0 .5 mg) with an interval of 5 minutes, the maximum total dose is 1 mg.

4. Administer infusion therapy (20 mL/kg) for hypotension with associated bradycardia.

5. For symptoms related to heart activity (hypotension, bradycardia) use:

a) adults: glucagon – initial dose of 5 mg by syringe through an IV catheter – can be repeated after 5-10 minutes, total maximum dose – 10 mg;
b ) children:

• • • • glucagon 1 mg by syringe through an IV catheter (weight 25-40 kg) – every 5 minutes if necessary;
      • glucagon 0.5 mg by syringe through an IV catheter (weight less than 25 kg) – every 5 minutes if necessary.

6. Use vasopressors after adequate fluid therapy (1-2 L of crystalloids) for hypotension (see “Shock” dosage guidelines for children and adults).

7. Use percutaneous electrocardiography in the absence of response to primary pharmacological interventions.

8. In case of convulsions, act according to the instruction “Shock”.

9. For a wide QRS complex (100 msec or longer), use sodium bicarbonate 1-2 mEq/kg IV. The infusion can be carried out before the narrowing of the QRS complex.

Patient safety

1. Percutaneous electrocardiostimulation cannot always cure hypotension.
2. Do not give activated charcoal to an unconscious patient.

Useful information for training

Key points

1. Precautions for providing assistance to children:

a) children can develop hypoglycemia from an overdose of beta-blockers, so it is important to determine the glucose level;
b) one pill can kill an infant. It is very important to carry out a thorough assessment of drugs to which the child may have had access, and to bring to the reception department those drugs that are suspected of being used by children.

2. Glucagon has side effects in the form of increased vomiting when used in such doses, so there may be a need for ondansetron prophylaxis.

3. Atropine has minimal side effects (may even be beneficial in mild overdose) – hypotension and bradycardia may be independent of each other, and blood pressure may not respond to bradycardia treatment.

4. Propranolol penetrates the blood-brain barrier and causes a change in consciousness, convulsions and widening of the QRS complex, similar to intoxication with tricyclic antidepressants.

Corresponding evaluation results

1. Certain beta-blockers, such as acebutolol and propranolol, can cause widening of the QRS complex.
2. Certain beta-blockers, such as acebutolol and pindolol, may cause tachycardia and hypertension.
3. Sotalol may lead to QT prolongation and ventricular arrhythmia.
4. Frequent reassessment is important because deterioration can occur rapidly and with catastrophic consequences.

Key elements of documentation

1. Reassess with further indication of signs and symptoms, as the patient’s condition may rapidly deteriorate.
2. Identification of the possible etiology of poisoning.
3. Time of manifestation of symptoms and time of initiation of treatment (specific for poisoning).
4. Treatment and response to treatment.

Criteria for the effectiveness of aid provision

1. Early control of the respiratory tract in case of rapid deterioration of the patient’s condition.

2. Detailed history of poisoning (overdose):

a) time of intake/exposure;
b) route of exposure to the substance;
c) amount of drug or toxin received (carefully collect all residues);
d) intake of alcohol or other intoxicating substances.

3. Choosing the right protocol and further treatment.

4. Documentation of parts after each re-inspection.

5. Recording of the ECG (periodic repetition of the ECG during long-term transportation; especially in children).

6. Correct assessment of ECG and segment intervals.