104 ROGERS. 



DEFICIENT BLOOD TKESSURE AS THE PEINCIPAL CAUSE OF POST CHOLERAIC 



UREMIA. 



Now that the use of hypertonic saline injections enables the great 

 majority of cholera cases to be tided over the very dangerous collapse 

 stage of the disease, that common and deadly late complication, uraemia, 

 has become relatively more important than ever. A comparative analysis 

 of all the cases treated at the Calcutta Medical College Hospital in 1907, 

 when transfusions were rarely given, and normal saline solution only 

 used, with those during the year 1908 when hypertonic injections were 

 employed, showed a slightly lower death rate from uraemia in the latter 

 than in the former series, namel}^, 12.8 per cent against 13.2 per cent. 

 Therefore it is clear that tlie strong saline solutions in no way predispose 

 to a deficient action of the kidneys. A study of the microscopical changes 

 in the kidneys of patients who had died of post-choleraic uraemia, led me 

 to suspect an actual mechanical obstniction to the circulation through the 

 organs, produced by the great effusion of blood into and around the 

 tubules. In order to test this hypothesis I measured the height required 

 to perfuse normal saline solution through the vessels, of the kidney 

 removed at the post mortem examination. These experiments were 

 carried on with healthy kidneys and with those removed from patients 

 who had died of choleraic urajmia. The results were very striking, for 

 whereas in normal organs a pressure of from 20 to 30 millimeters of mer- 

 cury sufficed to run a good stream of saline solution through the organs, 

 in the choleraic kidneys after death from uraemia one of 90 to 100 milli- 

 meters were necessary. In one case of death from pneumonia following 

 cholera, the patient having succumbed about a week after the renal 

 secretion had been reestablished, 30 millimeters pressure only was needed 

 to pass the solution through the kidney, showing that it was only in the 

 uraemic cases that the obstruction was present. I have therefore watched 

 the blood pressure day by day after recovery from the collapse state of 

 cholera with the following results : Out of ten cases of fatal uraemia 

 subsequent to intravenous transfusion in five the pressure toward the 

 end was not over 80 millimeters, in three not above 90 millimeters, while 

 in only two did it reach only 100 millimeters and that was just after 

 intravenous injections, two and five days, respectively, before death. 

 Moreover fatal uraemia was commoner in cases which had not been trans- 

 fused than in those which had been; although the former were much 

 milder cases in whom the measure did not appear to be necessary, but 

 in which the blood pressure usually rose only very slowly from the in- 

 variable low point during the acute stage of the disease. Again a 

 remarkable recovery from apparently hopeless choleraic uraemia, with 

 rapid stertorous breathing, followed the forcing up of the blood pressure 

 to over 100 millimeters by hypodermic injections of adrenalin and 

 digitalin. 



