Which of the following best describes a proper a dose-response assessment of a metered dose inhaler (MDI) bronchodilator?

a. Give 4 puffs one after the other, wait 1 min, repeat up to 16 puffs. The best dose is the highest dose given without side ef-fects.
b. Give 4 puffs spaced 1 to 2 min apart; re-peat up to 12 puffs with continued im-provement. The best dose provides maxi-mum subjective relief and the highest peak expiratory flow rate (PEFR) without side effects.
c. Give 12 puffs 1 min apart; repeat every 20 min until maximum relief of symptoms is achieved without side effects.
d. Give 2 puffs 1 to 2 min apart; repeat up to 6 puffs with continued improvement. The best dose provides maximum subjective relief and the highest PEFR without side effects.

ANS: B
A simple albuterol dose-response titration involves giving an initial 4 puffs (90 mcg/puff) at 1-min intervals through a pressurized MDI with a holding chamber. If after 5 min, airway ob-struction is not relieved, the respiratory therapist gives 1 puff/min until symptoms are relieved, heart rate increases to more than 20 beats/min, tremors increase, or 12 puffs are delivered. The best dose is that which provides maximum relief of symptoms and the highest PEFR without side effects.