Renal Hypothermia Using Self-made Cold-saline-perfused Bladders In Laparoscopic Partial Nephrectomy

Objective: Using Self-Made Cold-Saline-Perfused Bladders in theporcine model of laparoscopic partial nephrectomy, then the renalparenchymal temperature was quickly reduced to below20-25℃after therenal artery occlusion, and maintains a low temperature in order to protectrenal function.Also using ice slush in open surgery to lower renal temperaturethen comparing the two methods to further estimate the cooling effect ofself-made cold-saline-perfused bladders.Methods:Select six healthy pigs, weight30-35kg, and divide themrandomly into GroupA and Group B.Group A (experimental group)is theCold-Saline-Perfused Bladders cooling group and Group B (control group) isthe ice slush cooling group.GroupA: A group of pigs underwent laparoscopic partial nephrectomyand choose one kidney as the protection model of renal low temperature underintravenous anesthesia.After complete occlusion of the renal artery, theSelf-Made Cold-Saline-Perfused Bladders were surrounded onto renal surfaceand keep the kidney in a low temperature.After the occlusion of renalartery,the temperature sensors were placed in the renal parenchyma deeps in2.5-3.0cm.At the same time1-2℃cold saline was added into thebladders.Then each bladder was added150ml water. Turn off the inlet pipeafter the irrigation and turn on the suction pipe which quickly sucks waterintracapsular saline.The operation of the influent and effluent water as anexchange process which lasts1minute. Repeat the process and updates coldsaline once a minute.When the kidney temperature drops to below20℃,changed it to every1-2minutes to update cold saline, and out of the waterinterval time based on renal temperature adjustment, kidney low temperaturebetween15-20℃, continued to maintain to keep the renal temperature fluctuations. Continuous monitoring of renal artery occlusion renalparenchymal temperature for90minutes. Take the cut kidney tissue samples atthe80minute during the continuous monitoring. Open90minutes after therenal artery, kidney temperature continues to record rewarming within fiveminutes. Take the cut kidney tissue samples of the other kidney at the80minute of the renal artery occlusion for comparison.GroupB:Choose one kidney as the protection model of renal lowtemperature under intravenous anesthesia. Using the pre-prepared ice slusharound the topical kidney after complete occlusion the renal artery andcontinued to cool. Continuous monitoring of renal artery occlusion renalparenchymal temperature for90minutes. Take the cut kidney tissue samples atthe80minute during the continuous monitoring.Clear the perirenal pieces ofice and open renal artery after90minutes, renal temperature continues torecord rewarming within five minutes. Take the cut kidney tissue samples ofthe other kidney at the80minute of the renal artery occlusion for comparison.Take each kidney sample and trim it into1cm×1cm×0.3cm size, andimmediately put into4%formaldehyde solution (PBS) HE staining of fixed,sliced, select the slice flat, clear cell morphology and organizational structurerenal biopsy in400times the light microscope observation, comparedpathological changes, the initial judge the two methods on the renal protectiveeffect.The statistical processing of data: The rapid cooling stage is that15minutes after the renal artery occlusion.Select the temperature data of thisstage and compare the two cooling methods with repeated measures designanalysis of variance(ANOVA). to find whether there has difference betweenthe two methods. While P <0.05was considered statistically significant. UseSPSS13.0statistical software to process the experimental data.Results:Group A:The temperature of cold saline is1-2℃while the renalparenchymal temperature before renal artery occlusion is38℃. Therenal parenchyma temperature dropped to below25℃in13minutes after renal arteryocclusion, and down to below20℃in20minutes. Group B:The temperature of ice slush is-4℃while the renal parenchymal temperature before renal artery occlusion is38℃. The renal parenchyma temperature dropped to below25℃in8minutes after renal artery occlusion, and down to below20℃in13minutes.The temperature of ice water mixture surrounded by the kidney is-2℃.Group A: When the renal temperature dropped to below20℃,it canremain stable between17℃-19℃. Group B:When the renal temperaturedropped to below15℃within17minutes after the renal parenchymatemperature has remained at a low temperature below15℃.Group A: During the90-minute cooling process, the central temperaturedrop no more than1°C thus insulation measures are not taken.Group B:In thefirst experiment, the center temperature dropped from37.8°C to35.9°C in45minutes decreased by1.8℃.Then the insulation measures were taken.Subsequencely the blanket insulation were taken in the following twoexperiments to ensure the central temperature drop won't exceed1.5°C.The statistical processing of the cooling rate with group A and B: UseSPSS13.0statistical software to anaylze experimental data of Group A and Bduring the rapid cooling phase (1-15minutes).The result is Group B coolsquicker than Group A as F=19.156, P=0.012<0.05.Light microscopic changes in renal microstructure: renal warm ischemiafor30min expansion of the glomerulus capillary and tubular wall swelling,luminal expansion, seen in a small amount of powder dye slurry; warmischemia80min expansion of the glomerulus capillary, tissue edema,inflammatory cell infiltration; swelling of the renal tubular wall, lumenexpansion and lumen filled with homogeneous red dye exudate (serous,shedding of epithelial cells and a variety of tube), interstitial congestion.Group A: cold ischemia80min glomerular capillary no obvious expansion, noobvious inflammatory cell infiltration; tubular mildly dilated with mild edemaof the individual renal wall within the lumen without obvious oozing matter,interstitial congestion. Group B: cold ischemia80min slight expansion of theglomerular capillary, no significant inflammatory cell infiltration; renal tubularmild expansion of the wall no swelling, no significant exudate within the lumen, quality is no congestion.Conclusion:Using Self-Made Cold-Saline-Perfused Bladders during the laparoscopic partialnephrectomy in the porcine model,the temperature of renalparenchyma drops quicklyand creates acceptable renal tissue temperatures forpreservation of renal function.TheCold-Saline-Perfused Bladders cooling operations and surgical operations are independent of each other,after renal arteryocclusion surgical procedures can be continued. This partial cooling methodavoids the emergence of low body temperature also protect the renal functioneffectively and provides another new way of preservation of renal function.