Effect of Beta-Adrenergic Agonists Aerosolized by Freon Propellant on Tracheal Mucous Velocity and Cardiac Output

The present study was designed to assess the effects of two β-adrenergic agonists, isoproterenol sulfate and carbuterol hydrochloride, and aerosolized Freon propellant (a mixture of Freon Π, Freon 12, and Freon 114) on tracheal mucous velocity and cardiac output in anesthetized dogs. Five groups of ten animals each received the following dosages of aerosols: Freon, 20 puffs; isoproterenol, four puffs; carbuterol, four puffs; isoproterenol, 20 puffs; and carbuterol, 20 puffs. The puff was delivered by a standard metered aerosol; each puff of isoproterenol spray contained 75 µg of isoproterenol sulfate, and each puff of carbuterol spray contained 100 Mg of carbuterol hydrochloride. Tracheal mucous velocity was not changed by receiving Freon, but administration of both isoproterenol and carbuterol caused a significant increase in this measurement, with peak increases ranging from 74 to 111 percent above control values. The duration of action for four and 20 puffs of isoproterenol and for four puffs of carbuterol was two hours. Twenty puffs of carbuterol increased tracheal mucous velocity for three hours. Administration of carbuterol effected a slightly larger increase in cardiac output than isoproterenol. The duration of action for the increased cardiac output was shorter than the duration of action for the increased tracheal mucous velocity. These studies indicate that β-adrenergic agonists may have an important role in improving mucous transport in patients with chronic obstructive pulmonary disease in whom mucociliary clearance is depressed

A Technique for Bedside Bronchofiberoscopy

A technique for bedside bronchofiberoscopy is described which is based upon the use of a soft latex nasopharyngeal airway for introduction of the instrument. The procedure is performed under local anesthesia and is well tolerated by the patient No morbidity has occurred in 325 procedures on 285 patients. In addition to visualization of lesions and airway dynamics of the tracheobronchial tree, methods for obtaining selective cultures and bronchography have also been developed. The technique of bedside bronchofiberoscopy promises to be a major advance in the diagnosis and management of bronchopulmonary disorders