From Dental to Mental Institutions: A Quadruple Threat of Nitrous-Oxide Administration Before and During Mental Asylum Admission.

During the 19th century, patients undergoing anesthesia for surgical and dental procedures were at risk of being given hypoxic or dilute nitrous oxide on four separate occasions. Primary and secondary saturation during surgery could account for two administrations of 100% nitrous-oxide anesthesia, while both diagnostic and therapeutic doses of dilute nitrous oxide were frequently administered in mental asylums.

Denis Jourdanet (1815-1892) and the early recognition of the role of hypoxia at high altitude.

Denis Jourdanet (1815-1892) was a French physician who spent many years in Mexico studying the effects of high altitude. He was a major benefactor of Paul Bert (1833-1886), who is often called the father of high-altitude physiology because his book La pression barométrique was the first clear statement that the harmful effects of high altitude are caused by the low partial pressure of oxygen. However, Bert's writings make it clear that the first recognition of the critical role of hypoxia at high altitude should be credited to Jourdanet. Jourdanet noted that some of his patients at high altitude had features that are typical of anemia at sea level, including rapid pulse, dizziness, and occasional fainting spells. These symptoms were correctly attributed to the low oxygen level in the blood and he coined the terms "anoxyhémie" and "anémie barométrique" to draw a parallel between the effects of high altitude on the one hand and anemia at sea level on the other. He also studied the relations between barometric pressure and altitude, and the characteristics of the native populations in Mexico at different altitudes. Jourdanet believed that patients with various diseases including pulmonary tuberculosis were improved if they went to altitudes above 2,000 m. This led him to recommend "aérothérapie" in which these patients were treated in low-pressure chambers. Little has been written about Jourdanet, and his work deserves to be better known.

The introduction of oxygen for pneumonia as seen through the writings of two McGill University professors, William Osler and Jonathan Meakins.

Oxygen was identified at the end of the 18th century by three independent researchers. It was first used indiscriminately with other gases for treatment of pulmonary diseases by Thomas Beddoes. In the 19th century, the physiological properties of oxygen were identified by many researchers. In that same century, physicians used oxygen empirically for a variety of conditions. Osler, who wrote on pneumonia, appreciated that blood was "imperfectly oxidised" (sic) in pneumonia, but concluded that the toxicity of oxygen more than outweighed its possible benefits. Meakins applied the lessons he learned from studying the hypoxemia that resulted from poison gas in World War I to pneumonia. He confirmed that patients with severe pneumonia were hypoxemic and that many of their symptoms appeared to be relieved by inhalation of oxygen. Oxygen then became the standard therapy for pneumonia.

The discovery of retrolental fibroplasia and the role of oxygen: a historical review, 1942-1956.

Nearly 50 years after it was thought to be conquered, retinopathy of prematurity (ROP) continues to cause vision disturbances and blindness among prematurely born infants. During the 1940s and early 1950s, researchers and caregivers first identified and struggled to eliminate this problem, which seemed to come from nowhere and was concentrated among the most advanced premature nurseries in the U.S. Research studies initially identified many potential causes, none of which could be proved conclusively. By the mid 1950s, oxygen was identified as the culprit, and its use was immediately restricted. The rate of blindness among premature infants decreased significantly. ROP was not cured, however. By the 1960s, it had reappeared. The history of ROP serves to remind us that, despite our best intentions, the care and treatment of premature newborns will always carry with it the possibility of iatrogenic disease. This caution is worth remembering as we work to expand the quality and quantity of clinical research.

Paralysis and blindness during a balloon ascent to high altitude.

An account of the classic balloon ascent to over 29,000 ft (8840 m) by J. Glaisher and H. T. Coxwell on September 5, 1862, appeared in The Lancet and is reproduced here. Glaisher reported paralysis of his arms and legs and sudden loss of sight. Coxwell also lost the use of his hands and could only open the valve of the balloon to initiate its descent by seizing the cord with his teeth. These symptoms are unusual for acute hypoxia, and in a recent article Michael J. Doherty suggested that they may have been caused by decompression sickness. However, this seems unlikely based on many reported cases of subatmospheric decompression sickness.

Tachykinins in the control of breathing by hypoxia: pre- and post-genomic era.

This article highlights major findings from physiological and pharmacological studies conducted in the pre- and post-genomic era examining the roles of substance P (SP) and other tachykinins in the response of the carotid body to hypoxia, in the ventilatory response to hypoxia and in respiratory rhythm generation. In the post-genomic period, the hypoxic ventilatory responses of mice carrying targeted deletion of genes that affect synthesis or degradation or receptor interaction of SP have been examined by us and also by other investigators. A brief summary of the findings from these investigations will also be presented. The combined observations from the pre- and post-genomic era strongly support the involvement of SP and also other tachykinins in the control of respiration during hypoxia.

James Glaisher's 1862 account of balloon sickness: altitude, decompression injury, and hypoxemia.

In 1862, James Glaisher and Henry Coxwell ascended to 29,000 feet in an open hot-air balloon. During the ascent, Glaisher described marked neurologic compromises: appendicular and later truncal paralysis, blindness, initially preserved cognition, and subsequent loss of consciousness. The author examines Glaisher's account of balloon sickness by comparing it with other balloonists' observations and discussing it in the context of altitude sickness, decompression injury, and hypoxemia.