Volume 1

A system of medicine by eminent authorities in Great Britain, the United States and the Continent / edited by William Osler, assisted by Thomas McCrae.

Date:
1907-10
Catalogue details

Licence: In copyright

Credit: A system of medicine by eminent authorities in Great Britain, the United States and the Continent / edited by William Osler, assisted by Thomas McCrae. Source: Wellcome Collection.

Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.

    97/986 (page 73)
    ings whicli threw some liglit on the pathogenesis of the affection and could explain the clinical manifestations was given in 1879, by Leyden.* Symptoms.—Shortly after the return to the surface and after a pro- dromal stage consisting of pain, more or less severe, in the large joints, and also in the epigastrium and sometimes over the entire body, a paralysis occurs. The most frequent form of this is paraplegia, but sometimes , hemiplegia is observed. The onset and the character of the paralysis is very similar to that of transverse myelitis. If we take into consideration the frequent involvement of the sphincters (retention and constipation), > and the sensory disturbances, the resemblance to myelitis will be com- plete. All these symptoms may present variations in degree; in some cases the loss of power is only partial, in others more or less pronounced, and in still others absolute. Also both extremities may not equally be involved in regard to motor power as well as to sensations. In some cases, in addition to the myelitic symptoms there are also vertigo, head- ache, vomiting, slight confusion, convulsions, and double vision. Pros- tration is present in more severe cases. In fatal cases, deep coma, irregular respiration, and symptoms of cardiac paralysis, announce approaching death. As an occasional occurrence we may mention small perforations of the ear-drums, which are due to the pressure either externally or from within outward. Prognosis.—Generally speaking, recovery occurs frequently. In com- plete paralysis the loss of power may last only a few days. In severe cases the power may never return and the victim will remain permanently crippled. Death in protracted cases results fi-om the same causes as in chronic myelitis; namely, from suppurating bed-sores, cystitis, pyelitis, etc., or from an intercurrent disease. On the other hand, death may occur shortly after the onset as in acute myelitis. The hemiplegic form of paralysis bears usually a favorable prognosis. Deep coma with irreg- ular respiration is usually a bad omen. The degree of damage and consequently the probabilities of recovery depend in a general way largely upon personal predisposition, previous health (condition of heart, bloodvessels, kidneys, etc.), habits (alco- holism), age (fifty years is considered the maximum), upon the length of time spent in the caisson under high pressure, and finally and mainly upon the manner in which the diver is brought to the surface. That is to say, the less rapid and abrupt the decom])ression of air is done, the less damage the nervous system undergoes and the more chances for recovery there are. In the remarks on treatment this question will be discussed. Pathogenesis and Pathology.—The authors are divided in regard to the explanation of the symptoms. There are only two theories in vogue at the present time. According to one of them, the so-called gaseous theory, the blood while under high ])ressure becomes overcharged with gas (oxygen and carbonic acid), and the longer the exposure the greater the amount of gas. When the surface is reached, the gas attempts to escape through the lungs, but this can be done only gradually and progressively. In the meantime the superfluous gas circulates in the blood in bubbles, and may either form emboli or escape through the vessel-walls into the surrounding tissues and consequently produce considerable j)ressure. 'Arch. ]. Psych. IX. S. 31G.