400 PHYSIOLOGY CHAP. 



months when the second vagotorny follows within a few months 

 after the first (Herzen, Pawlow). Herzen succeeded in keeping 

 them alive by making a gastric fistula through which he fed the 

 vagotomised animal, so as to avoid pneumonia. Pawlow obtained 

 still better results by supplementing the gastric with the double 

 oesophageal fistula, as described in his experiments on sham 

 feeding (Vol. II. p. 108). 



The experiments of Nicolaides, however, proved that, without 

 artificial help, a strong dog can survive the second vagotomy 

 performed immediately after the wound of the first operation has 

 healed. At the Physiological Congress at Turin (1901) he showed 

 two large, robust, and healthy dogs, in which the vagi and sym- 

 pathetics had been divided in the neck in two successive sittings 

 at a few days' interval, ten months and nineteen months earlier. 

 These animals were well nourished and ate well, swallowing large 

 pieces of meat without difficulty. Phonation, too, had been recovered. 

 The post-mortem examination, made before a committee of the 

 Congress, showed that the two vagi had not regenerated, and their 

 peripheral ends were seen under the microscope completely de- 

 generated. There is at present no evidence to explain how these 

 two dogs succeeded in compensating perfectly, to all appearance 

 the disturbances of respiratory and cardiac rhythm, of phonation, 

 and of the mechanical and secretory activities of digestion. 



Still more marvellous is the survival of other dogs in which 

 double vagotomy was performed in one sitting. Among the 

 various cases recorded by the younger Herzen (1897) the 

 most interesting is that presented by Boddaert to the "Societe" 

 de Medecine de Gand" (1877). A strong bitch survived double 

 simultaneous vagotomy for three months and six days. During 

 the first week it seemed depressed, and vomited the milk and water 

 swallowed ; tachycardia and dyspnoea were marked. During 

 the second week improvement set in, and the animal ate freely 

 without vomiting. The vomiting decreased further during the 

 first and second months, and the animal's strength returned pro- 

 portionately. At the end of the second month its respiration 

 frequency was 14, and its pulse' 132 per minute. In the last 

 week of its life its nutrition was again disturbed, and its strength 

 gradually diminished. The post-mortem examination revealed 

 emphysema of the upper lobes of the lung and broncho-pneumonia' 

 of the right lower lobe, though microscopic examination failed to 

 discover any traces of food or buccal epithelium. The two stumps 

 of the vagus had united again, but it was obviously too early for 

 any complete regeneration. 



Gomez Ocana, again, at the International Congress of Medicine 

 at Madrid (1903), presented a large strong dog which had survived 

 bilateral section of the vago - sympathetic in the neck, per- 

 formed some three months earlier. After twelve days the normal 



