The most important development of the sur gical treatment of war wounds has been what is called by the French debridement, that is the thorough excision of all injured portions of tissue. The extent to which this clearing out of the wound was carried in war practice would have seemed utterly unjustified in civil surgery before the war. Where a penetrating bullet wound shows signs of infection, a cylindrical portion of the tissue around it is removed. In larger shell wounds, a layer of injured tissue is, as far as possible, removed, from every portion of the wound so as to present perfectly fresh vital surfaces for healing purposes. Large amounts of tissue are thus often removed, for experience has shown that it is in the end ever so much better for the patient. Any injured cells allowed to remain are of low resistive vi tality, have a tendency to die and then break down into material which forms an excellent culture medium for microbes. Where drainage is instituted, most of this will come away, but that is a much slower process and much more exhausting to the patient, and lowers the heal ing qualities of the part. It has been found by actual bacteriological observations that while very few bacteria are present shortly after the wound is infected, these multiply rapidly in the brood chamber created for them in the tissues, on the good medium for growth, while the healthy cells are handicapped by the presence of injured cells in their struggle against bacteria.
The war's experience with head injuries has developed a mode of treatment quite different from that in common use before. The surprise for military surgeons has been the wonderful tolerance of the brain to injuries. It was not an unusual thing to have wounded soldiers come into dressing stations as °walking cases,* who were suffering from fracture of the skull, even complicated by other injuries. The best surgery for these cases has proved the greatest possible limitation of intervention. Depressed bone fractures must, of course, be lifted, but missiles should not be searched for. There is least danger for the patient when the missile is left in situ, unless symptoms directly trace able to its presence develop. As a rule, anti septic rather than aseptic precautions are most valuable in saving lives in these cases. The experience of four years seems to indicate that the after effects of the retention of foreign bodies within the skull does not justify manipu lations in reaching them.
The use of poison gas has given rise to the most unsatisfactory medical feature of the war. In spite of the German signature to The Hague Convention article condemning the use of gas, the Germans proceeded to employ this mode of attack and found the Allies and the medical departments unprepared for it. At first heavy gases containing mainly bromine were used, favoring winds carrying them. Later gas hand grenades were employed. These gases had an
intensely irritant effect and produced suffoca tion or were followed by severe purulent bron chitis. Pulmonary edema often proved fatal. Gas masks overcame this mode of attack. Then long range gas shells were employed, sometimes with delayed action, so as to lull against precautions. At times, shells containing or °vomiting' gases were used for the displacement of masks. In the last phase of the war, "mustard gas,* said to be chemi cally dichlorethylsulphide, was employed. It was persistent and would hang about for hours and make dugouts perilous for days. It burned the skin, and clothes moistened with it produced escharotic effects. Many of the most important German advances were made by means of these gases as a preliminary. The Allies learned to neutralize and reply effectively to all of them.
When the gas was not concentrated enough to produce suffocation or set up fatal pulmo nary edema, the men usually recovered, though many of them went through a period of awful discomfort which was, of course, the reason why the use of gas was forbidden at The Hague. Comparatively few of those who sur vived presented serious lung lesions, though they had to be treated by the open air method, as for tuberculosis, as much as possible. We have learned from tuberculosis how tolerant the lungs are of even severe pathological con ditions and how readily, after a time, compen sation is secured. The question whether Bas ing predisposes to tuberculosis has been settled in the negative, though undoubtedly in certain cases latent foci of tuberculosis were made ac tive by the process.
Comparative mortalities from wounds and disease in modern war show what a great gain was made by surgery and sanitary science in the war. In the Russian campaign against Tur key in 1828, some 80,000 died of disease and about 20,000 of wounds. In General Scott's campaign in Mexico the deaths from disease were over 33 per cent of the effective strength. In the Crimean War, out of a total force of 300,900, the French lost by disease 75,000 and by wounds 20,000. In the Prussian war against Austria, of but seven week's duration, the losses by disease were 6,427 and by wounds 4,450 in an army of 437,000. In the Spanish-American War 2,565 deaths were from disease and 345 deaths from wounds, in an army of 274, 717. In the South African War the deaths from disease were 69 per thousand strength; from wounds, 42 per thousand. In the Russo Japanese War the deaths from disease were 41.8 per thousand strength and from wounds 72.9 per thousand strength, the ratio for the first time reversed. Out of 300,000 dead in the Civil War, in the armies of the North over 200,000 were from disease. In the Confederate armies, of 200,000 deaths, three-fourths were estimated as due to disease and one-fourth to the casual ties. (Figures furnished by the United States Surgeon-General's Office).