IVI Terbutaline for Bronchodilation

Availabilty: 

• Terbutaline Sulfate - 0.5mg/ml (in 1ml Vials)

1. Indication For bronchodilation

• When a rapid therapeutic response is required [subcutaneous, intramuscular, or i.v. bolus]
• The preferred routes will usually be subcutaneous or intramuscular. 
• When given as an i.v. bolus the injection must be made slowly noting patient response.

2. Adults Dosing & Dilution

Subcutaneous

• 0.25 mg recommended by manufacturer.
• Repeat dose (0.25 mg) if substantial clinical improvement does not occur within 15–30 minutes.
• If no response within another 15–30 minutes, consider other therapeutic measures.
• Manufacturer states total dosage should not exceed 0.5 mg within a 4-hour period.
• Hospitalized adults with asthma exacerbation: 0.25 mg every 20 minutes for a total of 3 doses 

Intravenous Infusion

• According to BNF 61 2012: 90-300 mcg/hr for 8-10 hours (concentration: 3-5 mcg/ml)
• Drugs.com : Continuous intravenous infusion: 0.08 to 6 mcg/kg/min 
• Frank Shann : 0.25mg STAT over 10 min, than 1-10 mcg/kg/hr
• Blue Book 14: 1.5 - 5mcg/min for 8-10h
• Malaysian Thoracic Society 1996: terbutaline (an alternative to aminophylline) at 3-20mcg/min after an initial intravenous bolus dose of 250mcg over 10 minutes
• based on other information leaflet : 3 - 5 ml (1.5 - 2.5 mg) in 500 ml 5% dextrose, saline or dextrose/saline (recommended infusion fluid is 5% dextrose)
• Saline should be avoided during pregnancy since the use of this diluent may increase the risk of producing pulmonary oedema. If saline has to be used, the patients should be carefully monitored

3. Paediatrics Dosing & Dilution

1. (BNF Children 2014)

Infusion:

• Initially 2-4mcg/kg as a loading dose
• Then 1 -10 mcg/kg/hour according to response and heart rate (Max: 300mcg/hr)
• (doses above 10mcg/kg/hr needs close monitoring)

Infusion: 

• 2-14y: 10mcg/kg up to QID (max 300mcg/dose)
• 15-17y: 250-500mcg up to QID

2. (Frank Shann)

• 3-6mcg/kg/min for 1 hour than 0.4-1mcg/kg/min

3. (other Product Leaflet)

• Children 2 - 15 years :
• 0.01 mg/kg body weight to a maximum of 0.3 mg total

Dilution:

• The recommended infusion fluid is 5% dextrose or NS0.9% or D5NS
  In the management of premature labour, the recommended infusion fluid is 5% dextrose. Saline should be avoided due to the risk of pulmonary oedema. 
• Saline should be avoided during pregnancy since the use of this diluent may increase the risk of producing pulmonary oedema.
• If saline is used, the patient should be carefully monitored
• If a syringe pump is available, the concentration of the drug infused should be 0.1 mg/ml 

4. Recommendation:

• Dilution is preferred to be carried out using Dextrose 5%
• Syringe pump: a concentration of 0.1mg/ml (or on fluid restriction)
•  1 mg terbutaline (2ml/2vial) + 8ml D5 or
•  5 mg terbutaline (10ml/10vial) + 40ml D5
• Syringe pump unavailable: a concentration of 0.01mg/ml 
• 1 mg terbutaline (2ml/2vial) + 98ml D5]

5. Current Practice (may differ according to setting)

• BNF (preferred as in accordance with manufacturers recommendations)
• can also make up to a concentration of 5mcg/ml (BNF)
• 2.5 mg (5ml) terbutaline (1ml/1vial) + 500ml D5

•  dosing at 90-300 mcg/hr (18-60ml/hr) : for 8-10 hours

References:

• BNF for Children 2015-2016
• BNF 61 2012
• https://www.medicines.org.uk/emc/medicine/155