Fatal decompression sickness following therapeutic hyperbaric environment (author's transl)

In Hannover/Germany in 1976 a so called "Society for Regenerative Hyperbaric Therapy" (Gesellschaft für Regenerative Uberdruck-Therapie) subjected 20 patients within two coupled multi-place chambers to a simulated hyperbaric environment, equivalent to a maximum of 4 ata, followed usually by gradual reductions of the pressure. The patients were of an average age of 67.2 years and were afflicted by various disorders. During one of the "dives" a patient developed air embolism of the central nervous system. During ensuing confusion of the chamber was opened suddenly, with resultant explosive reduction of the high pressure. This resulted in five letal accidents of decompression sickness. Post mortem examination revealed diffuse distribution of gas bubbles throughout the entire body. By elecronmicroscopy each bubble was covered by an osmiophilic coat. Post mortem findings are discussed and correlated with well-known and new clinical symptomes. These observations present for the first time fatal accidents of decompression sickness in humans, associated with hyperbaric air-therapy.     

The world population situation

Population experts appear to be reaching a consensus that there has been a perceptible decline over the last decade in the growth of the world's population. The decline is accounted for by the "new demographic transition" in the less developed countries (LDCs). The decline in fertility rates began in the 1950s in some LDCs and became more widespread during the 1970s. The process has not yet begun in many of the LDCs. During the 1960s it was observed that the declines in birth rates (to levels of 30 of less per 1000) were occurring mostly in small countries. Many of these countries were islands with levels of social and economic development above the developing country average. The key question is whether the recent downward trend in fertility in LDCs will continue, stabilize at the current level, or rise again. A primary concern about the future is that the poorer and less developed countries will end up with an increasing share of the world's population, with the share of the developed countries declining from 34% to 22% over the 1950-2000 period. Considerable differential exists in demographic growth patterns among various regions. The 12 largest LDCs (China, India, Indonesia, Brazil, Bangladesh, Pakistan, Nigeria, Mexico, Vietnam, Philippines, Thailand, Turkey) contain 55% of the current world population, and the fertility decline of these nations is expected to have the maximum impact. 7 of these countries have had fertility declines of 14-35%. The force of the "population momentum" must also be considered. Most developing country populations have a young age distribution with considerable potential for population growth even after the fertility level reaches a replacement level and the net reproduction rate equals 1.