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hind limb occlusion were reported in rats. They suggested that remote IPC has an at least equal potential for
translation to clinic. In contrast with these studies, Bedir et al. conducted a study on a porcine model, and
[33]
they compared serum creatinine levels and histopathological changes. But they were unable to demonstrate
any significant difference on behalf of IPC. Although large animal studies were not able to demonstrate any
protective effect of both remote and local IPC against IRI, this should be interpreted cautiously before giving
up this technique totally. Huang et al. recently published a randomized, controlled study in humans,
[13]
which was evaluating the effects of remote IPC. They demonstrated that lower limb IPC might reduce renal
damage in patients undergoing laparoscopic partial nephrectomy.

In conclusion we can say that the positive protective effects of remote IPC on kidney injury against ischemia
is limited, and its advantages are still questionable. Similar with local applications, remote IPC studies
conducted in small animals have yielded encouraging results, but their applicability to humans needs further
research. Unfortunately larger animal and human studies are very limited, and they have conflicting results.

IRI SECONDARY TO LAPAROSCOPIC/ROBOTIC PNEUMOPERITONEUM
Laparoscopic surgery requires adequate pneumoperitoneum throughout the surgery, but it has some
well-known physiologic adverse effects on cardiac , pulmonary , and renal systems . The decreased
[34]
[36]
[35]
blood flow to visceral organs and increased systemic vascular resistance, which are developed secondary
to increased intra-abdominal pressure are mainly responsible for these adverse effects. Additionally, the
subsequent desufflation following pneumoperitoneum may lead to an IRI. Eleftheriadis et al. were firstly
[36]
able to demonstrate the increased oxidative stress in the rat liver after pneumoperitoneum. In their study,
Glantzounis et al. reported increased levels of free oxygen radicals after laparoscopic procedures, which
[37]
were probably developed secondary to IRI. Akbulut et al. firstly demonstrated the pneumoperitoneum
[38]
related increased oxidative stress in kidneys.
To date lower pressure models [39,40] , low-pressure pneumoperitoneum with intermittent deflation at distinct
time points and IPC have been attempted to reduce ischemic injury regarding pneumoperitoneum. Many
[41]
human and animal studies have investigated the effects of increasing intraabdominal pressures (IAP) during
laparoscopy and the benefits of low IAP. In different studies Giraudo et al. and Samel et al. obviously
[40]
[39]
revealed that lower IAPs were related with reduced oxidative injury. But there are also some contradictory
studies. In their study on rats, Yilmaz et al. did not demonstrate any statistical significance in oxidative
[42]
stress parameters at both low and high intraabdominal pressures. Polat et al. confirmed these results in
[43]
their study with human subjects. A recent study conducted by Biler et al. clearly demonstrated that the
[44]
ischemic preconditioning method should be used to reduce IRIs, rather than other low-pressure models.

ROLE OF LAPAROSCOPIC/ROBOTIC IPC
Since Murry et al. first described the IPC, it was adopted for different laparoscopic studies. It has been
[1]
proposed as an effective therapeutic approach to enhance ischemia tolerance and preserve intraabdominal
organ function [3,45] . Yilmaz et al. first demonstrated that laparoscopic preconditioning might decrease
[46]
the oxidative stress in intestines following laparoscopic procedures in rats. In another study of the same
group, Yilmaz et al. demonstrated that LPC consisting of 10 min of insufflation followed by 10 min of
[47]
desufflation reduced the oxidative stress that induced by long-term increased intraabdominal pressure in
the plasma, liver, and kidney. But they also concluded that further studies were warranted to determine its
ideal timing, before incorporating LPC to clinical applications, because the experimental protocol was too
long to be applicable for the usage in humans. In the literature, different time periods for preconditioning
method have been reported. However, 5- or 10-min-ischemia followed by a reperfusion of 5-10 min is used
most commonly [1,48] . Arioz et al. published a study in 2009, and compared LPC 5-min with LPC 10-min.
[49]
As a result, they concluded that 5 min of pneumoperitoneum, and subsequent 5 min of desufflation, seems