Bends Explained

Details about many of the divers that I evaluated are included with comments on the way their dives got them into trouble and the chamber at City Island, NAHC. I discuss their treatment profiles and the results of their treatment. It presents a larger series of bent divers than any I am aware of. Should you find another comparable series contact me at [email protected]. Ideas about bends have changed from the concept that a bubble formed in the nervous system because of a rapid ascent or the joint by cavitation-negative pressure. Rapid ascent or joint motion caused the culprit to appear and pressure would make the bubble go away. Now we are focused on treating tissue damage with oxygen. But, we are still using pressure and oxygen to increase the partial pressure of oxygen in the affected tissue. The treatment of choice is the 5 hour long U.S. Navy Treatment Table 6 which washes out the nitrogen in the tissue and washes in the oxygen. Careful understanding of how my patients got bent and how they responded should make any diver more cautious regarding repetitive diving and a multi-day series of dives. Pressure at the deepest part of the dive washes in the nitrogen over time. Fatty tissue, that includes the central nervous system and peripheral nerves, absorbs more nitrogen than watery tissues such as muscle. Shaping-up to dive includes weight loss, abstinence during the duration of the series of dives, and improving lung function. Physical conditioning prevents tachycardia, a rapid heart beat, during exertion. A program of regular exercise two or three times a week prevents early fatigue during prolonged exertion, or increases stamina. Exercise such as walking 20 or more minutes a day for several weeks before diving is as important as paying for the trip. Swimming accustoms one to buoyancy, relaxing in the water, and adjusting temperature regulating reflexes such as vaso-constriction in the skin on immersion. Dive accidents sometimes do not have a treatable solution. Most "accidents" resolve after one re-compression breathing oxygen under pressure. Many patients were treated multiple times, and some did not get complete relief of their symptoms and/or neurological findings. Immediate therapy traditionally is in-water re-compression which has its drawbacks. It is difficult to administer and hypothermia, fatigue, and drowning are risks. Surface-On-Deck oxygen breathing from a face-mask or immediate re-compression in a chamber are always effective treatments. Transport to a facility has logistical problems and the destination chamber may not be functional when it is needed. The U.S. Navy Diving Manual Rev.6 Vol. 5 20-4.4.2.1 has procedures for In-Water Re-compression using AIR, 20-4.4.2.2 In-Water Re-compression Using Oxygen. Both sections advise going to 30 fsw and additional instructions for decompressing. If oxygen is used and the decompression has been completed then 3 hours of oxygen breathing is the procedure. One cylinder of oxygen and a face mask are good for one diver for 3 hours. Where are the other cylinders for other divers? The book is about the chamber that I personally operated and staffed. I was almost continually available. The number of bent divers that I treated, not all are included in the book because they were routine, speaks for itself. AAA, Avoid An Accident-Plan Safe Dives.

With the invention of compressed air in the 1840s, human divers could enter previously inaccessible deep water environments and engineers could design underwater mines and monumental bridges that had never been possible before. But a painful, sometimes fatal illness--decompression sickness, or the bends--mysteriously afflicted many of those who used compressed air. This book is a wide-ranging history of the wonders compressed air brought about and the suffering its unknown hazards inflicted. John L. Phillips explores the intertwining roles of science, technology, engineering, medicine, and politics in the invention of compressed air, the recognition and identification of decompression sickness, and the hundred-year-long process of learning to understand and treat the bends. The book begins with an overview of the biology and chemistry of respiration and a discussion of the steam engine that could generate compressed air. Drawing on previously unpublished letters, diaries, and notes, Phillips tells the story of early uses of compressed air, first observations of decompression sickness, growing awareness of the bends during construction of the Brooklyn Bridge, and efforts to understand the pathophysiology of the illness. He then considers employee health and safety issues, the science of diving today, and human limits to exploring the ocean deeps. In the history of compressed air and its illnesses, Phillips finds important lessons for dealing with other diseases yet to be confronted in the modern world.

This volume addresses the tectonic complexity and diversity of strike-slip restraining and releasing bends with 18 contributions divided into four thematic sections: a topical review of fault bends and their global distribution; bends, sedimentary basins and earthquake hazards; restraining bends, transpressional deformation and basement controls on development; releasing bends, transtensional deformation and fluid flow.

Very broad overview of the field intended for an interdisciplinary audience; Lively discussion of current challenges written in a colloquial style; Author is a rising star in this discipline; Suitably accessible for beginners and suitably rigorous for experts; Features extensive four-color illustrations; Appendices featuring homework assignments and reading lists complement the material in the main text