336 
SURGERY AND TRANSPLANTATION 
Figure 11. — Colony of dogs late following bilateral lung replantation at the same operation. 
the relatively prolonged warm ischemia time of 
the donor organ in that patient, as contrasted to 
the better function of the first clinical lung 
transplant that we had performed. 
With respect to bilateral pulmonary denerva- 
tion and respiratory reflex drive, it was evident 
to us that dogs which underwent simultaneous 
bilateral lung replantation were at a definite 
disadvantage with regard to ventilatory adjust- 
ments, this disadvantage lasting from several 
hours to two days following the operation. 
Pulmonary blood fiow also is influenced by pul- 
monary innervation.^ 
This excellent model of bilateral simultan- 
eous one-stage lung replantation has suggested 
that bilateral simultaneous lung transplantation 
should be technically and physiologically feasi- 
ble in man, and indeed this operation has al- 
ready been performed in human beings several 
times in other centers. 
LUNG ALLOTRANSPLANTATION 
Allotransplantation of the lung has been ex- 
tensively studied in dogs ^^"^'^ and has also 
been' performed in 28 human beings. The opera- 
tive technique employed for lung allotrans- 
plantation in the dog is essentially identical 
to that used for lung replantation, except that 
the lung transplant is derived from a second 
and genetically dissimilar animal. In fact, allo- 
transplantation of the lung is more easily ac- 
complished than replantation because with the 
former the structures to be anastomosed can be 
conveniently left long — ^this when one dog was 
utilized merely as the donor and the other as 
the recipient, as is usually done. However, with 
careful technique and using two teams, one can 
usually exchange lungs between dogs, thus 
achieving two experimental animals at the same 
operation. More recently, we have employed the 
