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X Fructus

Publications and source records attributed to X Fructus.

17 recordsLinked to original sources

[Conception of a decompression table].

After a given time at bottom, different tissues become saturated to different extents with nitrogen. In diving back to the surface a hydrostatic decompression occurs first, followed by the desaturation process some time later. It is during this time interval that all important events are taking place, namely: either a monophasic desaturation, whereby inert nitrogen gas is given off at the alveolar capillary interface. or a biphasic desaturation takes place, giving rise to gas bubbles in the blood-stream as well as in the tissues. We may then encounter pathologies which are benign incidents or, worse, lead to decompression sickness grade II. Since Paul Bert dedicated his thoughts in 1878 to this problem, numerous authors tried to explain this time delay, for trying to suppress it would be entirely unrealistic. Unfortunately, mathematical reasoning has too often overshadowed physiological thinking in these matters. We also stuck to Haldane's concept of 1908, in incorporating Workman's improvements of 1965. This method is based on two main principles: 1. all calculations were done with several "tissues" in mind. Their anatomical boundaries are of no importance as, only their desaturation half-times are relevant. 2. a natural limit is given by the critical saturation-coefficient (CS). It expresses the ratio between the partial pressure of the dissolved gas and the reduction of hydrostatic pressure during ascent (given as pressure gradient). Through experience we were able to put up tables which were more and more safe, in examining foremost the CS ratio and the desaturation times of certain tissues. Several examples are given, the values of which are statistically highly significant, as they incorporate the results of more than 60,000 air dives.

Decompression↗

Management of a complex diving accident.

After the accidental ascent of a diving bell from 80 m, one diver died from pulmonary barotrauma and the other-though grossly ill-survived. After recompression therapy, this diver was tetraplegic with evidence of patchy microcirculatory damage of brain, cord, liver, kidneys, and gut. All systems eventually returned to normal, except the spinal cord, mainly because of the post-recompression phase of management, in which pharmacological doses of steroids, hyperbaric oxygen, and dextran were used. Although function returned in the upper limbs, the diver remained paraplegic.

Accidents↗

[The Vasalva manoeuvre and the E.E.G. in a study of professional and trainee diverse (author's transl)].

The E.E.G., the oculocardiac reflex (OCR), the Valsalva manoeuvre and respiratory capacity, were studied and compared in 183 professional or trainee divers. There was a positive correlation between an alpha rhythm at or below 9 c/sec and a positive OCR. The Valsalva was more often positive in young subjects and trainee divers than in older subjects and professional divers. Also the Valsalva response was more likely to be positive when the subject's respiratory capacity was greater. These observations are used to make conclusions about the significance of a positive response to the Valsalva manoeuvre and about the value that can be attached to these various tests in subject selection.

Adolescent↗

[Dyslipidemia and hyperbaric osteonecrosis in the rat].

The authors subjected 149 adult Sprague-Dawley rats to repeated experimental dives, simulated to 160 m. Histopathological examination (femurs and tibias) revealed no evidence of osteonecrosis in either normal or dyslipidaemic animals. Study of the calcium metabolism using 45Ca revealed a significant drop in the levels of free and bound calcium and in the rate of exchange between the two compartments, in the dyslipidaemic animal placed in hyperbaric conditions.

Animals↗