Effect of increased abdominal pressure on cytokines (IL1 beta, IL6, TNFalpha), C-reactive protein (CRP), free radicals (NO, MDA), and histology. Surg Laparosc Endosc Percutan Tech. 2009;19:142-147. [PMID: 19390282 DOI: 10.1097/sle.0b013e31819cdda7]

Impact of Pneumoperitoneum on the Development of Acute Kidney Injury: Comparison Between Normal and Diabetic Rats

BACKGROUND

Minimally invasive surgery is considered the gold-standard approach for many surgical procedures. However, it requires CO2 insufflation and elevated intra-abdominal pressure (IAP), which may result in adverse pulmonary, cardiovascular, gastrointestinal, and renal changes. The kidneys are highly sensitive to pressure changes, where risk factors such as severe infection, dehydration, older age, and chronic kidney disease may aggravate the likelihood for the development of acute kidney injury (AKI). Unfortunately, the impact of diabetes mellitus on the deleterious effects of elevated IAP-induced AKI was not fully studied so far. The present study was designed to examine the effect of pneumoperitoneum on renal function and the development of AKI in diabetic rats.

MATERIALS AND METHODS

Sprague Dawley rats were divided into 2 groups: control (nondiabetic) rats (n=7) and diabetic rats (n=10). A Veress needle was introduced through the supravesical incision where inflating CO2 allowing the IAP to be increased to the desired pressures 7, 10, and 14 mm Hg for 45 minutes each and at the end of the experiment, the pressure was deflated to zero. During each pressure point, hemodynamic parameters were recorded and urine and blood samples were collected for analysis.

RESULTS

The baseline values of renal hemodynamic were significantly lower in diabetic rats. There were no major statistically significant changes from baseline in urinary flow, urinary sodium excretion (UNaV), glomerular filtration rate, and renal plasma flow during 7 mm Hg pressure in both groups. When the IAP was further elevated, a significant deterioration of these parameters was recorded. This trend was more pronounced among diabetic rats. When examining urinary neutrophil gelatinase-associated lipocalin, a linear correlation was observed between the IAP and the biomarker level. This correlation was more significant in the diabetic group.

CONCLUSION

The present study demonstrated a direct correlation between IAP elevation and the development of AKI. Diabetic rats were more sensitive to the deleterious effect of pneumoperitoneum, where urinary neutrophil gelatinase-associated lipocalin levels may be used as a future biomarker to predict postoperative AKI, especially in patients with diabetes.

Stress biomarkers in minimally invasive and conventional colorectal resections

INTRODUCTION

Any surgical procedure develops a stress situation for the patient, which can modulate the individual outcome. At present, there is only limited information about stress response in colorectal resections by laparoscopic compared to conventional surgery. Therefore, our objectives were the feasibility and the investigation of stress biomarkers including copeptin and steroid hormones before, during and after colorectal surgery.

METHODS

Eleven patients underwent minimally invasive and ten patients conventionally open colorectal surgery. Blood samples were collected before, during and 24 h after surgery and copeptin, NT-proBNP, cortisol, cortisone, interleukin-6 and glucose were analyzed.

RESULTS

Both, minimally invasive and conventional-open colorectal surgery caused a fast but heterogeneous response of stress biomarkers. However, the postoperative decrease of cortisol, cortisone and glucose differed between both groups. The stress biomarkers decreased faster down to baseline after minimally invasive surgery, while in open surgery cortisol, cortisone and glucose did not return to baseline within 24 h after operation.

CONCLUSIONS

We show in this feasibility study for the first time an increase of copeptin in combination with glucocorticoids as stress biomarkers by open surgery compared to minimally invasive procedures in patients undergoing colorectal surgery. Exceeding an individual threshold of 'stress burden' may have unfavorable effects on the long-time clinical outcome.

Slush nitrogen vitrification of human ovarian tissue does not alter gene expression and improves follicle health and progression in long-term in vitro culture

OBJECTIVE

To study whether slush nitrogen (SN) vs. liquid nitrogen (LN) vitrification affects human ovarian tissue gene expression and preserves follicle health during extended in vitro culture.

DESIGN

Randomized experimental study.

SETTING

University research laboratory.

PATIENT(S)

Ovarian biopsies collected by laparoscopic surgery from patients with benign gynaecologic conditions.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Ovarian strips were vitrified with LN or SN, warmed, and analyzed before or after culture for 9 days (d9) in gas-permeable dishes. Expression of genes involved in stress and toxicity pathways was analyzed in fresh and warmed strips by polymerase chain reaction (PCR) array and quantitative real-time-PCR. Fresh and vitrified/warmed strips were analyzed for follicle quality, progression, and viability before or after culture.

RESULT(S)

The SN vitrification preserved follicle quality better than LN (% grade 1 follicles: fresh control, 54.2; LN, 29.3; SN, 48.8). Quantitative reverse transcription-PCR demonstrated a noticeable up-regulation of 13 genes in LN samples (range, 10-35) and a markedly lower up-regulation of only 5 genes (range, 3.6-7.8) in SN samples. Long-term in vitro culture evidenced worse follicle quality and viability in LN samples than in both fresh and SN samples (% grade 1 follicle: fresh d0, 51.5; fresh d9, 41; LN d9, 16.4; SN d9, 55) and a highly significant reduction of primordial follicles and a concomitant increase of primary and secondary follicles in all samples. Follicle growth to the secondary stage was significantly higher in vitrified tissue than in fresh tissue, being better in SN than in LN vitrified tissue.

CONCLUSION(S)

Follicle quality, gene expression, viability, and progression are better preserved after SN vitrification.

Effects of propofol on the inflammatory response during robot-assisted laparoscopic radical prostatectomy: a prospective randomized controlled study

Robot-assisted laparoscopic radical prostatectomy (RALRP) is a minimally invasive procedure; however, some amount of surgical trauma that can trigger systemic inflammation remains. Moreover, pneumoperitoneum during RALRP induces ischemia–reperfusion injury (IRI). Propofol, an anesthetic, is known to have anti-inflammatory and antioxidant properties. In the present study, we compared the effects of propofol with those of desflurane on inflammation and IRI during RALRP via measurements of different biomarkers and evaluation of perioperative renal function. Fifty patients were randomized to receive either desflurane (n = 25) or propofol (n = 25) with remifentanil during RALRP. Serum levels of interleukin (IL)-6 (IL-6), tumor necrosis factor alpha, C-reactive protein, and nitric oxide were measured 10 min after anesthesia induction (T1), 100 min after carbon dioxide (CO₂) insufflation (T2), and 10 min after CO₂ deflation (T3). Perioperative urine outputs and the serum creatinine level at 24 h after surgery were also recorded. We found that IL-6 levels at T2 and T3 were higher than those at T1 in both groups, although the increases were significant attenuated only in the propofol group. The other parameters showed no differences among the three time points in both groups. The intraoperative urine output was significantly higher in the propofol group than in the desflurane group, while the creatinine level showed no significant changes in either group. Our findings suggest that propofol can not only attenuate the inflammatory response during and after pneumoperitoneum in patients undergoing RALRP but also prevent oliguria during pneumoperitoneum.

Protective effects of phycocyanin on ischemia/reperfusion liver injuries

In this study, phycocyanin (Pc) extracted from Spirulina platensis was used to evaluate its antioxidants effects after ischemia/reperfusion injury (IRI) using the ex-vivo model of isolated perfused rat liver. The rats were divided into eight groups : Control group, where livers were directly perfused after their removal; Cold Ischemia group (CI), livers were treated in the same way as the control group, except that after their collection, they were stored for 12 h and 24 h in the Krebs Henseleit (KH) preservation solution at 4 °C and Treated group (PHY), livers were preserved in the same way as the preceding group except that the KH solution was enriched with phycocyanin at two different concentrations. Pc, a powerful antioxidant, significantly reduced ischemia/reperfusion injury in the liver. In fact, the addition of phycocyanin to the preservation solution significantly decreased the activity of liver transaminases (AST) and (ALT), alkaline phosphatase (ALP), the rate of lipid peroxidation (MDA) and the activity of certain antioxidant enzymes, essentially glutathione-S-transferase (GST) and glutathione peroxidase (GPx). On the other hand, Pc increases the level of thiol groups in hepatic tissues. In conclusion, the results show the Pc-enriched KH conservation solution is effective in preserving the hepatic graft and protecting it against IRI by acting as a potent antioxidant against the products of oxidative stress.

Hydrogen protects against liver injury during CO2 pneumoperitoneum in rats

The aim of the current study was to identify the protective effect of hydrogen gas against liver injury during CO₂ pneumoperitoneum. Rats were randomly divided into three groups: control group (C group), pneumoperitoneum group (P15 group) and hydrogen group (H₂ group). Rats in the C group were subjected to anesthesia for 90 min. Rats in the P15 group received an abdominal insufflation of CO₂ for 90 min at an intra-abdominal pressure of 15 mmHg. Rats in the H₂ group received a hypodermic injection of hydrogen gas (0.2 mL/kg) and after 10 min they received an abdominal insufflation of CO₂ for 90 min at an intra-abdominal pressure of 15 mmHg. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured to evaluate liver function. Malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione (GSH) content were measured to evaluate oxidative stress. Nuclear factor E2-related factor 2 (Nrf2) and Nrf2 downstream target genes, apoptosis-related genes and inflammatory cytokine mRNA and protein expression were detected. Liver injury was detected under the microscope. Our results revealed that liver function, antioxidants content, inflammation and liver injury were improved after hydrogen preconditioning in H₂ group compared with P15 group. Overall, our results revealed that subcutaneous hydrogen injection could exert a protective effect against liver injury during CO₂ pneumoperitoneum through reducing oxidative stress, cell apoptosis and inflammatory cytokines release.

Endoscopic ultrasound-guided puncture suture device versus metal clip for gastric defect closure after endoscopic full-thickness resection: A randomized, comparative, porcine study

OBJECTIVE

The secure closure of the wall defect is a critical stage of endoscopic full-thickness resection (EFTR). The aim of this study was to compare the closure of post-EFTR defects using an endoscopic ultrasound-guided puncture suture device (PSD) with the metal clip (MC) technique in a randomized, comparative, porcine study.

METHODS

We performed a randomized comparative survival study that included 18 pigs. The circular EFTR defects with a diameter of approximately 20 mm were closed with either a PSD or MC. Serum levels of interleukin-6 (IL-6) were determined preoperatively and on a postoperative day (POD) 1, 3, and 7. Three animals from each group were sacrificed at the end of the 7 th , 14 th , and 30 th POD. Tissue samples retrieved from the closure sites were examined macroscopically and microscopically.

RESULTS

Resection and closure were performed in 18 pigs (100%) without major perioperative complications. The mean closure time was significantly longer in the MC group than in the PSD group (25.00 ± 3.16 min vs. 1.56 ± 0.39 min; P < 0.05). Preoperative and POD 7 serum levels of IL-6 did not differ between the two groups. However, on POD 1, the IL-6 levels were observed to be significantly greater in the MC group than in the PSD group (P < 0.005). No significant differences between the PSD and MC groups were observed at necropsy.

CONCLUSION

In this in vivo porcine model, PSD is a feasible device that achieves post-EFTR defect closure with a much shorter closure time and with less immunological responses than the MC technique.

Intra-abdominal pressure: Time ripe to revise management guidelines of acute pancreatitis?

AIM

To systematically review evidence on pathophysiology of intra-abdominal pressure (IAP) in acute pancreatitis (AP) with its clinical correlates.

METHODS

Systematic review of available evidence in English literature with relevant medical subject heading terms on PubMed, Medline and Scopus with further search from open access sources on internet as suggested by articles retrieved.

RESULTS

Intra-abdominal hypertension (IAH) is increasingly gaining recognition as a point of specific intervention with potential to alter disease outcome and improve mortality in AP. IAH can be expected in at least 17% of patients presenting with diagnosis of AP to a typical tertiary care hospital (prevalence increasing to 50% in those with severe disease). Abdominal compartment syndrome can be expected in at least 15% patients with severe disease. Recent guidelines on management of AP do not acknowledge utility of surveillance for IAP other than those by Japanese Society of Hepato-Biliary-Pancreatic Surgery. We further outline pathophysiologic mechanisms of IAH; understanding of which advances our knowledge and helps to coherently align common observed variations in management related conundrums (such as fluid therapy, nutrition and antibiotic prophylaxis) with potential to further individualize treatment in AP.

CONCLUSION

We suggest that IAP be given its due place in future practice guidelines and that recommendations be formed with help of a broader panel with inclusion of clinicians experienced in management of IAH.

Effect of Pneumoperitoneum on Oxidative Stress and Inflammation via the Arginase Pathway in Rats

PURPOSE

Oxidative stress during CO₂ pneumoperitoneum is reported to be associated with decreased bioactivity of nitric oxide (NO). However, the changes in endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS), and arginase during CO₂ pneumoperitoneum have not been elucidated.

MATERIALS AND METHODS

Thirty male Sprague-Dawley rats were randomized into three groups. After anesthesia induction, the abdominal cavities of the rats of groups intra-abdominal pressure (IAP)-10 and IAP-20 were insufflated with CO₂ at pressures of 10 mm Hg and 20 mm Hg, respectively, for 2 hours. The rats of group IAP-0 were not insufflated. After deflation, plasma NO was measured, while protein expression levels and activity of eNOS, iNOS, arginase (Arg) I, and Arg II were analyzed with aorta and lung tissue samples.

RESULTS

Plasma nitrite concentration and eNOS expression were significantly suppressed in groups IAP-10 and IAP-20 compared to IAP-0. While expression of iNOS and Arg I were comparable between the three groups, Arg II expression was significantly greater in group IAP-20 than in group IAP-0. Activity of eNOS was significantly lower in groups IAP-10 and IAP-20 than in group IAP-0, while iNOS activity was significantly greater in group IAP-20 than in groups IAP-0 and IAP-10. Arginase activity was significantly greater in group IAP-20 than in groups IAP-0 and IAP-10.

CONCLUSION

The activity of eNOS decreases during CO₂ pneumoperitoneum, while iNOS activity is significantly increased, a change that contributes to increased oxidative stress and inflammation. Moreover, arginase expression and activity is increased during CO₂ pneumoperitoneum, which seems to act inversely to the NO system.

The effects of arginase inhibitor on lung oxidative stress and inflammation caused by pneumoperitoneum in rats

Background

Pneumoperitoneum-induced oxidative stress and organ injury are known to be associated with nitric oxide (NO) inactivation. Because arginase competes with NO synthase (NOS) for a common substrate, L-arginine, arginase inhibition may increase NO bioavailability. Therefore, we evaluated the ability of the arginase inhibitor, 2 (S)-amino-6-boronohexanoic acid (ABH), to attenuate pneumoperitoneum-induced decrease of NO bioavailability and lung injury.

Methods

Thirty rats were randomly divided into the following groups: 1) the PP-ABH group received a subcutaneous injection of ABH (5 mg/kg) 1 h before induction of pneumoperitoneum (insufflation to intraperitoneal pressure of 15 mmHg for 60 min); 2) the PP group received saline by subcutaneous injection 1 h before induction of pneumoperitoneum; and 3) the control group received saline by subcutaneous injection before a sham procedure with no gas insufflation. After desufflation, blood was collected to determine levels of plasma nitrite, NOS, inflammatory cytokines, and malondialdehyde, a marker of oxidative stress. Lung tissue was obtained for histological evaluation.

Results

We found that plasma nitrite levels were lower in the PP group and higher in the PP-ABH group, compared with controls (P <0.01 and P <0.05, respectively). In the PP group, endothelial NOS activity was decreased and inducible NOS activity was increased compared with the PP-ABH and control groups. Malondialdehyde levels increased 3-fold in the PP group and 2-fold in the PP-ABH group compared with controls. Tumor necrosis factor-α, interleukin-6, and interleukin-1ß levels were elevated in the PP group compared to the control group, but the increase in cytokine production was attenuated or blocked in the PP-ABH group. Lung injury scores were 4.8-fold higher in the PP group and 2-fold higher in the PP-ABH group compared with controls (P <0.001 and P <0.01, respectively).

Discussion

Pneumoperitoneum decreases NO bioavailability and increases the inflammation cytokines, resulting in organ injuries. Inhibition of arginase activity could maintain NO bioavailability by attenuating pneumoperitoneum-induced changes in NOS activity. In addition, arginase inhibition attenuated the oxidative stress and inflammation and decreased the severity of lung injury caused by pneumoperitoneum.

Conclusions

By increasing NO bioavailability and suppressing oxidative stress and inflammation, pretreatment with an arginase inhibitor may protect against lung injury caused by pneumoperitoneum.

Protective effects of Hammada scoparia flavonoid-enriched fraction on liver injury induced by warm ischemia/reperfusion

CONTEXT

Hepatic ischemia/reperfusion injury (IRI) is a major cause of liver damage during liver surgery and transplantation. Plants have historically been used in treating liver damage, and Hammada scoparia (Pomel) (Chenopodiaceae) has been reported to possess a broad spectrum of pharmacological and therapeutic activities.

OBJECTIVE

In this study, a flavonoid-enriched fraction was used before the warm ischemia (WI) process as pharmacological preconditioning and in combination with technical postconditioning to evaluate their protective effects.

MATERIALS AND METHODS

The rats were divided into five groups: a sham group; a control group (Control-IR) that was submitted to 60 min WI; a Pharmacological Preconditioning group (PreC-IR) that received flavonoid-enriched fraction (200 mg/kg body weight); a Postconditioning group (PostC) and a PreC + PostC group.

RESULTS

The use of the flavonoid-enriched fraction was noted to significantly (p < 0.05) reduce liver injury, as evidenced by the decrease in liver transaminase activities (AST and ALT) and lactic dehydrogenase (LDH), alkaline phosphatase (ALP), and lipid peroxidation (TBARS), levels as well as the enhancement of antioxidant enzymes (catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx)) responses. The results also indicated that, compared with the separate application of pharmacological preconditioning and postconditioning, the combination of both treatments was more effective in reducing tissue oxidative stress levels through modulating SOD, GSH-PX, and CAT activities. Furthermore, the combined protocol further decreased the liver morphological score compared with solo treatment.

DISCUSSION AND CONCLUSION

Overall, the results indicate that the H. scoparia flavonoid-enriched fraction could be a promising candidate for future application as a pharmacological preconditioning agent against hepatic IRI.

Aprotinin reduces oxidative stress induced by pneumoperitoneum in rats

BACKGROUND

Ischemia-reperfusion injury induced by pneumoperitoneum is a well-studied entity, which increases oxidative stress during laparoscopic operations. The reported anti-inflammatory action of aprotinin was measured in a pneumoperitoneum model in rats for the first time in this study.

MATERIALS AND METHODS

A total of 60 male Albino Wistar rats were used in our protocol. Prolonged pneumoperitoneum (4 h) was applied, causing splanchnic ischemia and a period of reperfusion with a duration of 60 or 180 min followed. Several cytokines and markers of oxidative stress were measured in liver, small intestine, and lungs to compare the aprotinin group with the control group. Tissue inflammation was also evaluated and compared between groups using a five-scaled histopathologic score.

RESULTS

In aprotinin group values of biochemical markers (tumor necrosis factor α, interleukin 6, endothelin 1, C reactive protein, pro-oxidant-antioxidant balance, and carbonyl proteins) were lower in all tissues studied. Statistical significance was greater in liver and lungs (P < 0.05). Histopathologic examination revealed significant difference between control and aprotinin groups in all tissues examined. Aprotinin groups showed mild to moderate lesions, while in control groups severe to very severe inflammation was present. Aprotinin subgroup with prolonged reperfusion period (180 min) showed milder lesions in all tissues than the rest of the groups.

CONCLUSIONS

Aprotinin reduced inflammatory response and oxidative stress induced by pneumoperitoneum in liver, small intestine, and lungs.

Management of mechanical ventilation during laparoscopic surgery

Laparoscopy is widely used in the surgical treatment of a number of diseases. Its advantages are generally believed to lie on its minimal invasiveness, better cosmetic outcome and shorter length of hospital stay based on surgical expertise and state-of-the-art equipment. Thousands of laparoscopic surgical procedures performed safely prove that mechanical ventilation during anaesthesia for laparoscopy is well tolerated by a vast majority of patients. However, the effects of pneumoperitoneum are particularly relevant to patients with underlying lung disease as well as to the increasing number of patients with higher-than-normal body mass index. Moreover, many surgical procedures are significantly longer in duration when performed with laparoscopic techniques. Taken together, these factors impose special care for the management of mechanical ventilation during laparoscopic surgery. The purpose of the review is to summarise the consequences of pneumoperitoneum on the standard monitoring of mechanical ventilation during anaesthesia and to discuss the rationale of using a protective ventilation strategy during laparoscopic surgery. The consequences of chest wall derangement occurring during pneumoperitoneum on airway pressure and central venous pressure, together with the role of end-tidal-CO2 monitoring are emphasised. Ventilatory and non-ventilatory strategies to protect the lung are discussed.

Increased serum adenosine and interleukin 10 levels as new laboratory markers of increased intra-abdominal pressure

BACKGROUND

Increased intra-abdominal pressure (IAP), intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are severe complications of surgical interventions with a high rate of mortality. The technique of IAP measurement is accurate, precise, reproducible and cost-effective. However, laboratory measures for monitoring of IAH have not been defined. We investigated the linkage between the serum levels of adenosine and interleukin 10 (IL-10) with IAP.

METHODS

The sera of 25 surgical patients with IAP <12 mmHg and of 45 surgical patients with IAP >12 mmHg were tested. Serum adenosine concentration was measured by HPLC. Serum IL-1β, IL-2, IL-4, IL-10, TNFα, IFNγ and IL-10 were determined by enzyme linked immunosorbent assay (ELISA). CRP was measured by nephelometry.

RESULTS

Significant correlations of IAP were found only with serum levels of adenosine and IL-10. In the sera of patients with IAP >12 mmHg, the levels of both adenosine (1.61 versus 0.06 µM, p < 0.01) and IL-10 (63.23 versus 27.27 pg/ml, p < 0.01) were significantly higher than those in patients with IAP <12 mmHg. Moreover, significant correlations were found between individual patient IAP-adenosine values (r = 0.766, p < 0.001), IAP-IL-10 values (r = 0.792, p < 0.001) and adenosine-IL-10 values (r = 0.888, p < 0.001). A direct linear correlation between IAP-adenosine and IAP-10 values was only observed with IAP >15 (Grade II-IV).

CONCLUSION

We report associations between IAP and the serum adenosine and IL-10 levels providing new tools for the laboratory monitoring of IAH as well as further understanding of the pathomechanisms contributing to ACS.