ADMINISTRATION ROUTES:
IV, Nebulised, Inhaler
ALTERNATIVE NAMES:
Ventolin, Combivent, Duolin, Albuterol, Respigen, Salamol
ICU INDICATIONS:
- Bronchospasm
- Hyperkalaemia (pending definitive treatment)
PRESENTATION AND ADMINISTRATION:
IV:
5 mg in 5 mL solution
For infusion add either 5 mg to 50 mL or 10 mg to 100 mL of compatible IV fluid to give solution of 0.1 mg (100 mcg) per mL
Note: Ventolin solution for IV infusion (5 mg in 5 mL) should not be injected undiluted. If a bolus dose of salbutamol is required, dilute with Water for injection. For example, add 0.5 mL (500 mcg) to 10 mL to make a solution of 50 mcg/ mL. Inject bolus doses of up to 5 mL & repeat as required.
Compatible with the following IV fluids:
0.9% sodium chloride, 5% glucose, Glucose and sodium chloride
Store at room temperature. Protect from light.
Inhaler:
Respigen, Salamol & Ventolin: 100 mcg/dose
Combivent: salbutamol 100 mcg/dose plus ipratropium 20 mcg/dose
Nebuliser:
Ventolin: 2.5 mg/2.5 mL nebules and 5 mg/2.5 mL nebules
Duolin: 2.5 mg salbutamol and 500 mcg ipratropium / 2.5 mL nebules
DOSAGE:
IV:
Bolus:
250 mcg
Infusion:
0 - 10 mL/hr of 100 mcg/mL solution
Metered Dose Inhaler (MDI):
Unintubated:
1 - 2 puffs PRN
Intubated:
5 - 10 puffs into ventilator circuit using MDI adaptor
Use MDI rather than nebulisers for intubated patients
Nebuliser:
2.5 - 5 mg nebulisers PRN
May initially need to be administered continuously.
DOSAGE IN RENAL FAILURE AND RENAL REPLACEMENT THERAPY:
Dose as in normal renal function
DOSAGE IN PAEDIATRICS:
IV:
Bolus:
10 mcg/kg (max 500 mcg) over 2 minutes
Minimum volume 5 mL - dilute with 0.9% Saline if required. Can repeat dose at 10 minutes.
Infusion:
Initial 5 -10 mcg/kg/min for 1 hour
Reduce to 1 - 2 mcg/kg/min thereafter
For weight < 16 kg:
- Draw up 3 mg/kg of neat IV salbutamol solution (1 mg/mL)
- Add to 50 mL syringe to make up to 50 mL with 5% dextrose
- 1 mL/hr = 1 mcg/kg/min
For weight ≥ 16 kg:
- Draw up neat IV salbutamol solution (1 mg/mL) into a 50 mL syringe
- Do not dilute
- Rate in mL/hr = 0.06 x weight (kg) x dose (microgram/kg/min)
For example: to give 5 mcg/kg/min to a 20kg child, set rate at 0.06 x 20 x 5 = 6 mL/hr
CLINICAL PHARMACOLOGY:
Salbutamol is a selective β2 adrenoceptor agonist which acts on bronchial smooth muscle to relieve bronchospasm
CONTRAINDICATIONS:
- Hypersensitivity to salbutamol
WARNINGS:
Hypokalaemia:
Potentially serious hypokalaemia may result from β2 agonist therapy mainly from parenteral and nebulised administration. Particular caution is advised in acute severe asthma as this effect may be potentiated by concomitant treatment with xanthine derivatives, steroids, diuretics and hypoxia. It is recommended that serum potassium levels are frequently monitored.
Hyperlactataemia & hyperglycaemia:
As with other β2 agonists, salbutamol administration can cause a rise in serum lactate. Salbutamol promotes glycolysis, increasing both glucose & pyruvate. It also promotes gluconeogensis. Excessive pyruvate can't enter the Krebs cycle so is converted to lactate. This usually resolves quickly after cessation of salbutamol.
Salbutamol toxicity:
In addition to biochemical markers above, salbutamol toxicity may manifest with clinically apparent symptoms & signs. These include tachycardia, tremors, anxiety, nausea, vomiting, agitation, cardiac arrhythmias, and seizures. If toxicity is suspected and side-effects are not tolerable, salbutamol should be reduced or stopped.
PRECAUTIONS:
General:
Salbutamol should be administered cautiously to patients suffering from hyperthyroidism, cardiovascular disease or diabetes.
Laboratory Tests:
No tests in addition to routine ICU tests are required. As above, hypokalaemia, hyperglycaemia and hyperlactataemia may be observed.
Drug/Laboratory Test Interactions:
None of note.
IMPORTANT DRUG INTERACTIONS IN ICU:
Salbutamol will enhance the activity of other β2 sympathomimetics. β receptor blocking agents such as propranolol inhibit the activity of salbutamol. The effects of salbutamol may be enhanced by concomitant administration of aminophylline or other xanthines.
ADVERSE REACTIONS:
Musculoskeletal:
Fine tremor of skeletal muscle (particularly of the hands), palpitations and muscle cramps
Cardiovascular:
Tachycardia, peripheral vasodilation with hypotension
Hypersensitivity reactions:
Angioedema, urticaria, bronchospasm, hypotension and collapse have been rarely reported
Respiratory:
Paradoxical bronchospasm may also occur requiring immediate discontinuation of therapy and institution of appropriate treatment