Mdi Presentation

1. Delivery of bronchodilators with
metred-dose inhalers (MDI) in
mechanically ventilated patients:
Should We Invest?
Sharon Lamb

2. •Intensive Care Unit, Aintree University Hospitals NHS
Foundation Trust – currently considering metred-dose
inhalers to deliver bronchodilators in mechanically
ventilated patients
•Prompted by equipment change
•Literature review to establish evidence base to underpin
decision making
•Pros and Cons
•Consider nursing implications
•Outline

3. •British Nursing Index
•CINAHL
•Cochrane Library
•HMIC
•Medline
•Web of Science
•Search strategy developed using
thesaurus terms and natural
language key terms
•Identifying the Evidence Base

4. •Ease of Administration
•Decreased Costs
•Reliable Dosing
•Freedom from Contanimation
•But in mechanical ventilation it
deposits in the endotracheal tube
and ventilator circuit making it
inefficient.
•However evidence shows despite
smaller doses reaching the lower
lung significant bronchodilator
effect is achieved.
•The Theory Underpinning Use of MDIs
Dhand and Tobin
(1996)

5. •Device
•Ventilator used
•Ventilator Mode/Settings
•Location in Circuit
•Humidification
•Density of inhaled gas
•Spacer use impacts:
–Ventilator deposition
–Lung deposition
•Patient Condition
»Garner et al , 2002
•Key elements for success

6. •In Vitro testing of the use of MDI to deliver dry powder
bronchodilators shows that 16.2% - 20% of drugs could be
delivered to the patient (Everard, Devadason and Le Soeuf,
1996 and Fink et al 1999)
•Georgopoulos et al (2000) indicates that MDI achieves
similar results to bronchodilators delivered by nebulizers at
reduced dose
•Simplicity of use is cited by Hess (1991),
Dhand (1996) and Georgopoulos (2000)
and results from integration with the
ventilator circuit.
The Evidence for MDI Use

7. •Georgopoulous et al, 2000 make an economic case for
the use of MDI suggesting cost savings per year of
$300,000 per year in a typical 700 bed hospital. Given the
state of NHS finances this level of saving may be
attractive to management!
•Nebulizer use can lead patient/ventilator dyssynchrony if
the inline nebulizer exceeds the patients inspiratory flow
rate, Beaty et al 1989.
The Evidence for MDI Use

8. •Garner et al (2002) found no significant change in
respiratory mechanics or haemodynamics when
comparing delivery by MDI or Nebulizer.
•Marik et al (1999) report that nebulizers deliver the highest
dosage, however they do suggest the use of MDI
produces equal if not better results.
•Training
•Experience, change management
•Time
•Using Nebulizers in Ventilated Patients
•Implications for Nursing

9. •In Vitro tests by Fink et al (1999) suggest that for optimum
delivery humidification should not be used this is not a
realistic option for patients in the intensive care unit where
humidification is used to prevent damage of the airway
mucosa (Lange and Finlay, 2000)
•The majority of articles cite reduced levels of infection a
reason for MDI use, however they fail to detail evidence to
justify this claim. It must therefore be discounted.
•Cost-effectiveness
–Greek Study – translatable?
–ICU organisation
–Pharmaceutical costs
–Georgopoulos et al (2000)
•Conclusion

10. •There are many variables impacting delivery
–Device
–Equipment Used
–Settings
–Location in Circuit
–Spacer
–Staff Experience
•Literature base – evidence base is not new, the range
of articles is from the late 80's to 2002.
•Conclusion

11. •References
•Beaty, C.D., Ritz, R.H, and Benson, M.S. (1989) Continuous in-line nebulizers complicate pressure
support ventilation. Chest 96 pp.1360–1363.
•Dhand, R. and Tobin, M.J. (1996) Bronchodilator delivery with metered-dose inhalers in mechanically-
ventilated patients. European Respiratory Journal. 9 pp.585-595.
•Everard, M.L., Devadason, S.G. and Le Souef, P.N. (1996) In vitro assessment of drug delivery through
an endotracheal tube using a dry powder inhaler delivery system. Thorax 51 pp.75-77.
•Fink, J.B., Dhand, R., Grychowski, J., Fahey, P.J. And Tobin, M.J. (1999) Reconciling In Vitro and In Vivo
measurements of aerosil delivery from a metred-dose inhaler during mechanical ventilation and defining
efficiency enhancing factors. Am J Resp Crit Care Med 159 pp.63-68.
•Garner, S.S., Weist, D.B., Bradley, J.W. And Habib, D.M. (2002) Two administration methods for inhaled
albutamol in intubated patients. Archives of Diseases in Childhood 87 pp.49-5
•Georgopoulos, D., Moulidi,E., Kondili, E. and Klimathianki, M. (2000) Bronchodilator deliverpy with
metered-dose inhaler during mechanical ventilation. Critical Care 4 pp.227-234
•Hess, D. (1991) Aerosol bronchodilator delivery during mechanical ventilation. Nebulizer or inhaler?.
Chest 100 (4) p.1103.
•Lange, C. and Finlay, W. (2000) Overcoming the adverse effects of humidity in aerosol delivery via
presurised metered-dose inhalers during mechanical ventilation. Am J Resp Crit Care Med. 161
pp.1614-1618.