Evaluation of the peripheral circulation during surgery by the difference between the central and peripheral temperature

The peripheral circulation during surgery was evaluated by the difference between rectal and sole deep temperature (RT-SDT) in 160 patients. Moreover it was investigated whether the peripheral circulation is influenced by the operation site, the method of anesthesia, the age of patient, the volume of infusion and blood loss. In many patients during intracranial, thoracic and upper abdominal surgeries, RT-SDT dissociated with time. But the change of RT-SDT varied with the anesthetic method. During upper abdominal surgery, RT-SDT tended to dissociate wtih the halothane (H) or enflurane (E)+N2O anesthesia and the wide dissociation was observed with fentanyl+droperidol+N2O anesthesia (NLA) on and after the 4th hour during the surgery. In contrast, RT-SDT continued to converge throughout the surgery in H or E+N2O+epidural anesthesia. The influence on RT-SDT of age, volume of infusion and blood loss, varied with the anesthetic method also. RT-SDT on the 4th hour during surgery correlated with the age of the patient, the volume of infusion in the H+N2O anesthesia, and with the volume of blood loss under NLA. The peripheral circulation during the surgery is affected seriously by anesthesia and the site as well as time of the operation. Therefore the anesthetic method should be selected in consideration of the type, length and site of operation. Some counter-measures should be taken in order to maintain good peripheral circulation in long operations.