Effect of Retroperitoneoscopic Donor Nephrectomy on Tissue Oxidative Stress Markers in Rabbit Pneumoretroperitoneum Model

Minimally invasive surgery and oxidative stress response: what have we learned from animal studies?

Oxidative stress (OS) is an integral part of the surgical stress response. Minimally invasive surgery causes less trauma, and thus attenuated stress response is anticipated. However, the pneumoperitoneum or pneumoretroperitoneum is implicated in free radical production. This study reviewed available data on the impact of minimally invasive surgery on OS response of animal models in a systematic way. Databases were searched up to and including January 2010. Most of the studies investigated the effect of pneumoperitoneum on OS, 3 studies investigated the effect of pneumoretroperitoneum on OS. There was a great heterogeneity on experimental conditions including animal models, measured OS markers, methods, and time periods of measurement. Published animal data do not allow a reliable conclusion on the effect of minimally invasive surgery on OS because of the great heterogeneity of experimental conditions. Besides, most studies focus on the effect of pneumoperitoneum, without taking into consideration the effect of less surgical trauma.

Understanding Intra-Abdominal Hypertension

Received November 10, 2009. Received Revised June 17, 2010. Submitted June 21, 2010. Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are highly morbid conditions that are common and underrecognized in the intensive care unit. Intra-abdominal hypertension affects the critically ill patient population and is not solely limited to the trauma and surgical subgroups. The recognition of IAH and ACS as distinct clinical states has become more apparent. Extensive bench and clinical research has shed significant light into the definition, incidence, etiology, physiology, clinical manifestations, and treatment strategies. Although further research into this morbid condition is needed, improvement in recognition is a critical first step. This review aims to scrutinize the basic science and clinical literature available on this condition in a surgically focused, organ-system-based approach.

Effect of Carbon Dioxide Pneumoretroperitoneum on Bacterial Translocation in an Experimental Retroperitoneoscopy Model

PURPOSE

To evaluate the effect of artificial CO2 pneumoretroperitoneum on bacterial translocation in an experimental retroperitoneoscopy model.

MATERIALS AND METHODS

Eighteen adult male New Zealand White rabbits weighing 2.5 to 3 kg were divided into two groups. Group 1 (control group) consisted of 6 rabbits, while the remaining 12 served as the pneumoretroperitoneum group (group 2). In group 1, the left retroperitoneal space was dissected with a 50-mL balloon without CO2 insufflation, and the animals were kept under anesthesia for 3 hours with the balloons inflated. In group 2, after balloon dissection as in group 1, CO2 insufflation was applied at 1 L/min to achieve a pressure of 10 to 12 mm Hg for 3 hours. Afterward, all animals were sacrificed, and samples were taken from the blood, retroperitoneal area, lungs, liver, mesentery, heart, kidneys, ureters, bladder, colon, small intestine, and spleen and carried to the microbiology laboratory in Carry-Blair medium. Bacterial growth was evaluated using standard techniques.

RESULTS

All animals survived the experimental procedures. None of the rabbits in the control group demonstrated any bacterial translocation in the sampled tissues. In the pneumoretroperitoneum group, one rabbit was found to have 10(2) colony-forming units of E. coli in the kidney, but this was considered to be the result of contamination, not translocation.

CONCLUSION

Carbon dioxide pneumoretroperitoneum does not seem to cause bacteremia or bacterial translocation in this experimental model. Retroperitoneoscopy probably does not create any additional risk of septic complications.

Effect of Warm Ischemia on Graft Outcome in Laparoscopic Donor Nephrectomy

PURPOSE

To assess the impact of warm ischemia time (WIT) on delayed graft function (DGF), graft loss, and graft function in laparoscopic donor nephrectomy (LDN).

PATIENTS AND METHODS

We prospectively studied 100 kidney recipients from LDN donors from 2001 to 2003. For comparison of graft outcome with different extents of WIT, recipients were divided into three groups: group A received kidneys having 4 to 6 minutes, group B kidneys having >6 to 10 minutes, and group C kidneys having >10 minutes of WIT. The median follow-up was 415 days (range 11-791) days.

RESULTS

The mean kidney WIT was 8.7 minutes (range 4-17 minutes). Graft outcome (DGF, graft loss, and median serum creatinine) was not significantly different in the three groups.

CONCLUSIONS

Different extents of WIT in LDN, within the range of our study, were not associated with an adverse outcome in kidney transplantation.

The effect of verapamil on the prevention of ischemia/reperfusion injury in the experimental retroperitoneoscopic donor nephrectomy model

BACKGROUND

This study investigated the effect of intravenous administration of verapamil in prevention of the injury caused by free oxygen radicals generated in a rabbit retroperitoneoscopic donor nephrectomy model.

METHODS

Twenty-four adult New Zealand rabbits were divided into four groups. In group I, balloon dissection of the left retroperitoneal space was performed. In group II, CO2 at 10 mmHg was applied for 3 hours after the balloon dissection. In group III, laparotomy was performed, the left renal pedicle was clamped for 3 min, and the clamp was removed 5 min before nephrectomy. In group IV, 2 min before the attempt 0.2 mg/kg verapamil was given intravenously, and the same procedure was employed as in group III. Nephrectomy was performed after each experiment. The concentrations of malonyl dialdehyde (MDA), reduced glutathione (GSH), and protein carbonyl content were measured in renal tissue samples as markers of oxidative stress.

RESULTS

Pneumoretroperitoneum (Prp) promoted oxidative stress in renal tissues, with an increase of MDA and protein carbonyl content. The verapamil- pretreated group (group IV) showed statistical significantly lower values of MDA and protein carbonyl content when compared with group II and III (p < 0.05), whereas tissue GSH concentrations were unchanged in all groups.

CONCLUSIONS

Our study showed that Prp causes increased oxidative stress in renal tissue. Warm ischemia lasting 3 min did not exert an additive effect on Prp-associated oxidative stress. Verapamil reduces the oxidative stress markers caused by Prp.