Background
Laparoscopic donor nephrectomy has
become the first choice for living donor kidney transplantation,
offering advantages over open donor nephrectomy.
This study aimed to evaluate kidney tissue metabolism
during and after pneumoperitoneum using a microdialysis
technique.
Methods
Eight pigs underwent laparotomy and implantation
of two microdialysis catheters: one in the cortex and
one in the medulla of the left kidney. After laparotomy, the
abdominal wall was closed, and pneumoperitoneum was
induced with a constant standard pressure of 16 to 18
mmHg for 4 h, followed by rapid desufflation. In microdialysis
samples collected from intrarenal catheters,
markers of ischemia (glucose, lactate, pyruvate, and lactate–
pyruvate ratio) and the marker of cell membrane
injury (glycerol) were monitored.
Results
There were no changes in glucose, lactate, or
pyruvate level before, during, or after pneumoperitoneum,
either in the cortex or in the medulla. Additionally, the
calculated lactate–pyruvate ratio did not show signs of
ischemia during or after pneumoperitoneum. However,
with regard to the marker of cell injury, glycerol increased
in the medulla after decompression from 22.57 ± 3.76 to
35.67 ± 5.43 mmol/l (
p < 0.01). This release of glycerol in
the medulla was significantly higher than in the cortex
(area under the curve [AUC], 22.18 ± 4.87 vs
34.79 ± 7.88 mmol/l;
p < 0.01).
Conclusions
The pattern of metabolic changes monitored
in the kidney during and after pneumoperitoneum indicates
some kind of cell injury predominant in the medulla without
any signs of kidney ischemia. This nonischemic injury could
be related to hyperperfusion of the kidney after decompression
or injury to cells attributable to mechanical cell
expansion at the point of rapid decompression.