ABSTRACT
Renal transplantation is the best method of treatment for renal failure and anesthetic management during this procedure is of great importance. Proper dosage of the anesthetic drug for maintaining the respective depth is crucial as well. Arterial unclamping following anastomosis between the donor and recipient's kidney vessels, during which the functional kidney is inserted in the recipient's circulation, is a critical step in transplantation. To investigate the changes in Bispectral number and pupil dilatation as confirmed and probable markers of anesthesia depth have been investigated. This descriptive-analytic study was conducted on 25 patients undergoing renal transplantation in Razi hospital. Alteration in the depth of anesthesia was analyzed using BIS [Bispectral] index [at unclamping moment and its highest value within five minutes following unclamping] as well as pupil dilatation [5 minutes after unclamping]. All the patients underwent identical method of general anesthesia. Data were analyzed using SPSS version16, paired t- test and Mann-Whitney U test. Mean and SD value of the maximum BIS number within 5 minutes after arterial unclamping [68/32 +/- 9/13] and its value at unclamping moment [59/48 +/- 10/65] were significantly different [P<0.0001].The pupil became wider in 84% of the patients immediately after unclamping. No significant relationship was found between the pupil size and BIS change. Considering the present findings, it seems that the depth of anesthesia declines after arterial unclamping following vascular anastomosis of the transplanted kidney. We also found a new sign in kidney transplantation anesthesia, introduced as "PUPIL SIGN", that happens prior to urination from the transplanted kidney, which could have clinical implications for early prognosis of transplantation success