[A study on postoperative management and pre-and postoperative changes of blood volume in orthopedic surgery (author's transl)].

In order to apply adequate postoperative management of patients in the orthopedic surgery, the in vivo effects of the operations were investigated in the present study, from various viewpoints such as circulatory functions, metabolism of proteins, and hepatic and renal functions. In addition, the circulating blood volumes were determined in order to know the variations in the amount of blood loss from the operated regions during and after operations so as to improve the operative and postoperative management. On the basis of the results, the countermeasures against the adverse variations in blood volume were also investigated. Pediatric patients were found to be prone to develop more appreciable systemic postoperative reactions than those in adult ages, especially so in those of circulatory system, peripheral blood, hepatic functions, and protein metabolism, and also prone to be more affected by operative procedures. Senile patients were found to be prone to have less reserve capacity in circulation, peripheral blood, renal functions, and protein metabolism, and also prone to show delayed postoperative reactions and slower recoveries. The results of measurement of circulating blood volume in pre- and postoperations revealed that the loss of circulating blood in most patients was greater than the bleeding weight during the operation measured by gause count, and that, on the day following the operation, the blood volume was reduced by about 10-15% than those immediately after the operation. It was concluded that, as a whole, no changes causing serious deviation from the normal physiological ranges occur except in pediatric and senile patients. On the basis of the above findings, most appreciable systemic postoperative reactions of the operative procedures in orthopedic surgery would be attributed to by loss of blood volume during operations and that the postoperative hemorrhage from bone structure (which is usually difficult to control) or the postoperative hemorrhage after removal of air tourniquet would be almost negligible.