Delivery of Beta-2-Agonists in Intubated Patients
- need to consider:
- -> dose
- -> side effect profile
- -> effectiveness
- -> cost
- excellent systemic delivery
- may have variable delivery to the areas that are not perfused
- systemic effects and side effects maximal
- easy to administer
- less predictable onset
- lower bioavailability
- systemic side effects are more pronounced
- easy to administer via an adapter
- adaptor must be close to ETT
- multiples of dose in non-intubated are required (10 puffs/treatment)
- give on inspiration
- slow inspiratory flow rates (increased inspiratory time) increases delivery to airways
- large TV (> 500mL) ensure optimal delivery
- ideally patient should have a large ETT (>7.0)
- helium-oxygen mixtures increase deposition to lower airways
- does not require break in circuit
- optimal = inline spacer (increased cost + may become reservoir for infection)
- minimal systemic side effects
- humidification can decrease delivery to the respiratory tract c/o greater deposition in the ventilator circuit
- high flow of gas (6-8L/min) -> producers small respirable particles
- in the spontaneously breathing patient only 10% reaches the lower respiratory tract
- in the mechanically ventilated 1-15% reaches the LRT
- can be given continuously
- maximises local delivery while minimizing system absorption
- easy to administer
- requires break in circuit for each treatment
- variable interaction with ventilator (some cannot compensate for flow)
References and Links
- Dhand R, Tobin MJ. Bronchodilator delivery with metered-dose inhalers in mechanically-ventilated patients. Eur Respir J. 1996 Mar;9(3):585-95. PMID: 8730023.
Chris is an Intensivist and ECMO specialist at the Alfred ICU in Melbourne. He is also a Clinical Adjunct Associate Professor at Monash University. He is a co-founder of the Australia and New Zealand Clinician Educator Network (ANZCEN) and is the Lead for the ANZCEN Clinician Educator Incubator programme. He is on the Board of Directors for the Intensive Care Foundation and is a First Part Examiner for the College of Intensive Care Medicine. He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives.
After finishing his medical degree at the University of Auckland, he continued post-graduate training in New Zealand as well as Australia’s Northern Territory, Perth and Melbourne. He has completed fellowship training in both intensive care medicine and emergency medicine, as well as post-graduate training in biochemistry, clinical toxicology, clinical epidemiology, and health professional education.
He is actively involved in in using translational simulation to improve patient care and the design of processes and systems at Alfred Health. He coordinates the Alfred ICU’s education and simulation programmes and runs the unit’s education website, INTENSIVE. He created the ‘Critically Ill Airway’ course and teaches on numerous courses around the world. He is one of the founders of the FOAM movement (Free Open-Access Medical education) and is co-creator of litfl.com, the RAGE podcast, the Resuscitology course, and the SMACC conference.
His one great achievement is being the father of three amazing children.
On Twitter, he is @precordialthump.
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