As a basic principle inhaled treatment should be preferred compared with oral or parenteral application even in emergency situations. However patients presenting with acute and severe airway obstruction usually have a high breathing rate, inspiratory force is decreased considerably, and mostly they are extremely agitated. Under these conditions dry powder inhalers cannot be used reliably.
In emergency situations pressurized metered-dose inhalers (pMDI) should be used but only with an appropriate spacer since stressed patients are not able to perform a complicated inhalation manoeuvre – essential for effective treatment – correctly. If necessary the device in connection with a spacer should be operated by a helper.
A patient in status asthmaticus should receive 2 to 4 puffs of a rapid-acting β2-agonist, e.g. fenoterol, salbutamol or terbutaline, inhaled via a spacer device. Therapy can be applied as effectively and safely by compressor systems or ultrasonic nebulizers. A system with in- and expiratory valve can be used permanently during tidal breathing without any additional requirements regarding cooperation and coordination. Since no significant differences exist concerning the efficacy of both kind of devices in emergency situations the use of MDI plus spacer appears to be more appropriate regarding cost effectiveness.
Newman KB, Milne S, Hamilton C, Hall K. A Comparison of albuterol administered by metered-dose inhaler and spacer with albuterol by nebulizer in adults presenting to an urban emergency department with acute asthma. 2002. Chest; 121: 1036-1041
Rodrigo GJ, Rodrigo C. Continuous vs. intermittent ß-agonists in the treatment of acute adult asthma: A systematic review with meta-analysis. 2002. Chest; 122: 160-165
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