The Bezold-Jarisch reflex. A historical perspective of cardiopulmonary reflexes.

The Bezold-Jarisch reflex is an eponym for a triad of responses (apnea, bradycardia, and hypotension) following intravenous injection of veratrum alkaloids in experimental animals. The observation was first reported in 1867 by von Bezold and Hirt, and confirmed in 1938-1940 by Jarisch. The triad depends on intact vagi and is mediated through cranial nervous medullary centers controlling respiration, heart rate, and vasomotor tone.

Cardiovascular disease and occupational exposure to environmental tobacco smoke.

Results of chemical analysis, animal experiments, and human studies are reviewed, criticized, and found not to support claims of an association between workers exposed to environmental tobacco smoke (ETS) and occupational coronary heart disease. This review also recommends refinement of the use of dose surrogates, as presently practiced by the Occupational Safety and Health Administration (OSHA), for regulating indoor emissions from combustion engines, coal furnaces, tobacco leaf processing, rayon viscose manufacturing, and rubber curing. The work standards OSHA uses for regulation of these complex mixtures could also be used in evaluating ETS and relate to the following constituents of ETS: nicotine, carbon monoxide, benzo[a]pyrene, and carbon disulfide.