Page 459 - Clinical Application of Mechanical Ventilation

Pharmacotherapy for Mechanical Ventilation 425

catecholamines. The modification in the chemical structure results in more specific
beta-2 receptor binding and delayed degradation by COMT and MAO. As a re-
sult, catecholamine derivatives (noncatecholamines) offer less cardiac adverse effects
and prolonged bronchodilation than the catecholamines. Additionally, resistance
to COMT degradation makes these agents suitable for enteral administration—
although, beta-2 specificity may be lost via this route (Gardenhire, 2007). Long-
acting beta adrenergic medications such as aformoterol tartrate (Brovana) have the
benefit of less frequent dosing, but the question of increased risk of death when used
as monotherapy with patients who have asthma remains unresolved (Hinkle, 2011).
Table 13-3 shows the relative receptor actions, dosage, and frequency of use of
some common sympathomimetics.
Adverse Effects. The adverse effects of adrenergic bronchodilators include tachycardia,
palpitations, skeletal muscle tremors, and nervousness. The degree of adverse effects
depends on the mode of administration, dosage, frequency of administration, pres-
ence of preexisting cardiac disease, and the specific adrenergic agent used. In most
cases the benefits of bronchodilation will outweigh the potential adverse effects.

TABLE 13-3 Adrenergic Bronchodilators

Action
Catecholamines Receptor Inhalation Dosage Frequency

Epinephrine (adrenaline) α . β-1 . β-2 Neb (1%) 0.25 to 0.5 mL QID

Racemic Epinephrine (Micro- α . β-1 . β-2 Neb (2.25%) 0.25 to 0.5 mL QID
Nefrin, Vaponefrin, Asmanefrin)

Isoproterenol (Isuprel) β-1 , β-2 Neb (0.5%) 0.25 to 0.5 mL QID
Catecholamine Derivatives

Bitolterol (prodrug) (Tornalate) β-1 , β-2 MDI 2 puffs Q 4 to 6°

Metaproterenol (Alupent, β-1 , β-2 Neb (5%) 0.3 mL TID/QID
Metaprel) MDI 2 to 3 puffs Q 4°

Albuterol (Proventil, Ventolin) β-1 , β-2 Neb (0.5%) 0.5 mL TID/QID
MDI, DPI 2 puffs TID/QID
Levalbuterol (Xopenex) β-1 , β-2 Neb, MDI 0.63 to 1.25 mg TID/QID

Terbutaline (Brethaire, Brethine, β-1 , β-2 MDI 2 puffs QID
Bricanyl) DPI 1 puff QID

Pirbuterol (Maxair) β-1 , β-2 MDI 1 to 2 puffs Q 4 to 6°

Salmeterol Xinafoate (Serevent) β-1 , β-2 MDI, DPI 2 puffs BID
Arformoterol Tartrate (Brovana) β-1 , β-2 Neb 15 mcg BID
© Cengage Learning 2014

Copyright 2013 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s).
Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it.