Respiratory
1854, Pol and Watelle clinical observations, Pont de la Guillotière bridge construction, France
Decompression sickness emerged as a recognized medical problem during the industrial expansion of the nineteenth century, when engineering projects began requiring workers to labor inside pressurized caissons beneath rivers and harbors. Physicians of that era struggled to explain the devastating and sometimes fatal illness that struck workers upon emerging from these high-pressure environments. The condition's investigation laid essential groundwork for understanding how gases behaved in human blood under varying atmospheric pressures.
Historical Narrative
Before the industrial age created conditions in which humans were routinely exposed to greatly elevated atmospheric pressures, physicians had no occasion to observe or describe what would later be called decompression sickness. Ancient and medieval medical literature contained no meaningful precursor to its recognition, though divers harvesting sponges, pearls, and coral in Mediterranean and East Asian waters likely suffered its effects without any framework for understanding their pain or paralysis. Historical accounts from ancient Greece and Rome mentioned the physical suffering of divers, and some scholars later suggested that certain descriptions of joint pain and paralysis following sustained breath-hold diving may have represented early unrecorded instances of the condition.
The immediate context for decompression sickness as a medical problem was the widespread deployment of pneumatic caisson technology in mid-nineteenth century civil engineering. Caissons were pressurized underwater chambers that allowed workers to excavate river and harbor beds for bridge and tunnel foundations while keeping water at bay through compressed air. Workers laboring in these environments at pressures well above normal atmospheric levels began experiencing a characteristic and often agonizing cluster of physical effects upon returning to surface conditions — joint pains so severe that men walked in a peculiar bent posture that gave the condition one of its early popular names, the bends.
The first systematic medical investigation of caisson illness fell to French physician B. Pol and T.J.J. Watelle, who in 1854 published observations of workers on the Pont de la Guillotière bridge project in Paris, noting that the illness only appeared after workers left the pressurized environment rather than while inside it. This observation was fundamental, though Pol and Watelle did not yet possess a theoretical explanation for the phenomenon. English physician Andrew Smith conducted extensive clinical observations during the construction of the Brooklyn Bridge beginning in the 1870s, documenting cases among caisson workers and noting the range of severity, from mild joint pain to paralysis and death.
The pivotal theoretical breakthrough came from French physiologist Paul Bert, whose landmark 1878 work La Pression Barométrique synthesized decades of experimental investigation into the effects of atmospheric pressure on living organisms. Bert demonstrated through careful animal experimentation that the illness resulted from nitrogen bubbles forming in the blood and tissues when pressure was reduced too rapidly, the dissolved gas coming out of solution much as carbonation escapes a bottle when its pressure is released. His identification of nitrogen as the culpable agent and the mechanism of bubble formation transformed the condition from a mysterious occupational scourge into a physiologically explicable phenomenon.
Building upon Bert's theoretical foundation, Scottish physiologist John Scott Haldane conducted influential experimental work in the early twentieth century under commission from the British Admiralty, which was deeply concerned about the safety of military divers. Haldane and colleagues developed the concept of staged decompression — the controlled, gradual reduction of pressure across defined time intervals — publishing their findings in 1908. His mathematical models of nitrogen absorption and elimination in tissues became the basis for the first formal decompression tables, which represented an attempt to engineer safety into the process of returning from high-pressure environments.
The history of decompression sickness thus traced a path from bewildering industrial catastrophe through physiological theory to engineered prevention, with the late nineteenth and early twentieth centuries marking its decisive period of scientific understanding.
Key Historical Figures
Historical narrative only — this page describes how Decompression sickness was understood historically. It is not medical advice and does not describe current diagnosis or treatment. Sourced from verified medical history references (NIH, Encyclopaedia Britannica, and standard medical history texts). See our medical disclaimer.