Comparison of peritoneal oxidative stress during laparoscopy and laparotomy

Vitamin E administration as preventive measures for peritoneal/intra-abdominal adhesions: A systematic review and meta-analysis

Background

Peritoneal adhesion still becoming a common complication after abdominal surgeries and become a significant threat to digestive surgeons nowadays. Vitamin E might offer benefits for preventing peritoneal adhesions because of its antioxidant, anti-inflammatory, and anti-fibroblastic properties. This study sought to analyze the relationship between vitamin E administration and peritoneal/intra-abdominal adhesions in rat models.

Methods

Potential articles were searched by using specific keywords on Scopus, PubMed, PMC, and Cochrane Library databases until March 12th, 2022. All published studies on vitamin E and peritoneal/abdominal adhesions in rat models were collected. Statistical analysis was performed by using Review Manager 5.4 software.

Results

A total of 9 studies were included in the final analysis. Pooled analysis of the evidences yielded an association between vitamin E and decreased incidence of substantial peritoneal/intra-abdominal adhesions (RR 0.46; 95%CI: 0.33–0.64, p < 0.00001, I² = 61%, random-effect modeling); and reduction in the mean grade of adhesions (Mean Difference −1.53; 95%CI: −2.00, −1.06, p < 0.00001, I² = 98%, random-effect modeling).

Conclusions

This study proposes that vitamin E supplementation might offer benefits in the prevention of peritoneal/intra-abdominal adhesions. More in-vivo studies with larger sample sizes and proper methods are still needed to confirm the results of our study. If possible, studies on humans might also be warranted.

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Peritoneal adhesion still become common problem after abdominal surgery.

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Our study indicates vitamin E can reduce incidence of peritoneal adhesions.

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Vitamin E can also reduce the mean grade of abdominal adhesions.

Effects of Heated Pneumoperitoneum on Inflammation, Oxidative Stress, and Peritoneal Histology in Female Dogs That Underwent Video-Assisted Ovariohysterectomy

Laparoscopic procedures require the creation of pneumoperitoneum. CO₂, which must be cold and dry, is the standard gas used in such surgeries. The type of gas used, its temperature, and moisture may change the peritoneal surface and cause systemic and local oxidative stress. Our objective is to evaluate the influence of pneumoperitoneum heating on the occurrence of histological lesions in the peritoneum, inflammation, plasma oxidative stress, and on the mesothelial surface in patients undergoing video-assisted ovariohysterectomy. Twenty canine females were included and distributed evenly into two groups: heated CO₂ (HG) and unheated CO₂ (UHG). The biomarkers of inflammation and oxidative stress were evaluated before insufflation (T0), at 30 min (T1), and at 60 min (T2) of exposure to CO₂. Biopsies of the peritoneal tissue for histological evaluation were performed at T0 and T2. Regarding plasma parameters, acetylcholinesterase (AChE) showed a greater activity in the HG at T1 (p=0.0268) and T2 (p=0.0423); in turn, butyrylcholinesterase (BChE) showed a greater activity at T2 in the HG (p=0.0175) compared with T0. Catalase activity (CAT) was different between HG times; it was higher at T1 (p=0.0253). There was a decrease in the levels of substances reactive to thiobarbituric acid (TBARS) (p=0.0117) and in glutathione (GSH) (p=0.0114) between T0 and T2 in the UHG. Regarding tissue oxidative stress, the CAT in the HG showed a greater activity at T2 than T1 (p=0.0150). By comparing the groups at each time, there was a difference only at T2 (p=0.0288), being greater in the HG. Regarding the activity of superoxide dismutase (SOD) in the HG, there was a difference between T2 in relation to T0 and T1 (p=0.0181); finally, there was an increase only at T1 (p=0.0287) in the UHG when comparing groups at the same time. There were no differences in the histological parameters evaluated. Our study demonstrates that the heating of CO₂ generates a greater inflammatory response and forms reactive oxygen species (ROS) at the plasma and peritoneal levels.

Macrophages mediate colon carcinoma cell adhesion in the rat liver after exposure to lipopolysaccharide

The surgical resection of primary colorectal cancer is associated with an enhanced risk of liver metastases. Moreover, bacterial translocation or anastomic leakage during resection has been shown to correlate with a poor long-term surgical outcome, suggesting that bacterial products may contribute to the formation of metastases. Driven by these premises, we investigated the role of the bacterial product lipopolysaccharide (LPS) in the generation of liver metastases. Intraperitoneal injection of LPS led to enhanced tumor-cell adhesion to the rat liver as early as 1.5 h post-administration. Furthermore, a rapid loss of the expression of the tight junction protein zonula occludens-1 (ZO-1) was observed, suggesting that LPS disrupts the integrity of the microvasculature. LPS addition to endothelial-macrophage co-cultures damaged endothelial monolayers and caused the formation of intercellular gaps, which was accompanied by increased tumor-cell adhesion. These results suggest that macrophages are involved in the endothelial damage resulting from exposure to LPS. Interestingly, the expression levels of of ZO-1 were not affected by LPS treatment in rats in which liver macrophages had been depleted as well as in rats that had been treated with a reactive oxygen species (ROS) scavenger. In both settings, decreased tumor-cell adhesion was observed. Taken together, our findings indicate that LPS induces ROS release by macrophages, resulting in the damage of the vascular lining of the liver and hence allowing increased tumor-cell adherence. Thus, peri-operative treatments that prevent the activation of macrophages and—as a consequence—limit endothelial damage and tumor-cell adhesion may significantly improve the long-term outcome of cancer patients undergoing surgical tumor resection.

A comparison of the oxidative stress response in single-incision laparoscopic versus multi-trocar laparoscopic totally extraperitoneal inguinal hernia repair

Introduction

Surgical treatment is always associated with tissue damage and the subsequent development of oxidative stress.

Aim

To compare the oxidative stress response in patients treated operatively for inguinal hernia with multi-trocar laparoscopic totally extraperitoneal technique (TEP) or single-incision laparoscopic totally extraperitoneal technique (TEP-SI).

Material and methods

A randomized group of 34 patients with one-sided inguinal hernia was enrolled in the study. Seventeen patients were treated with a standard TEP method (group 1) and the other 17 patients were treated with the TEP-SI technique (group 2). Thiobarbituric acid reactive substances (TBARS) and total antioxidant status (TAS) as the oxidative stress markers were measured before surgery (0), 1 day (1) and 4 days (2) after surgery.

Results

A decrease in TAS on the first day after surgery was observed in both groups. Sustained reduction on the fourth day after surgery was observed in group 1, whereas in group 2 an increase followed. A statistically significant difference was observed in TAS (2 : 0) ratio with a meaningful decrease in group 1. TBARS concentration was elevated 1 day after surgery in both groups. It remained at an elevated level on the fourth day after surgery in group 1, while it decreased in group 2. The duration of surgery was higher in group 2 (mean: 57.5 min) than in group 1 (mean: 50.0 min) (p = 0.0286).

Conclusions

Oxidative stress levels are lower in patients treated operatively by TEP-SI technique than by TEP. TEP-SI may be considered as a less invasive technique associated with less tissue injury.

Comparison of the Effects of Sevoflurane and Desflurane on Thiol-Disulfide Homeostasis in Patients Undergoing Laparoscopic Cholecystectomy

Objective

This study aims to compare the effects of different inhalation anesthetics on oxidative status by measuring thiol-disulfide homeostasis in laparoscopic cholecystectomy surgeries. The effect of inhaler agents on thiol-disulfide homeostasis that shows the oxidative status in laparoscopic cholecystectomy is unknown.

Materials and Methods

In this study, 71 patients planned to undergo laparoscopic cholecystectomy under general anesthesia were included. They were divided into two groups: desflurane (group D, n: 35) and sevoflurane (group S, n: 36). Blood samples were taken before induction (T1), at 30th minute of insufflation (T2) (30th min of ischemia), and at 30th min postdeflation (T3) (30th min of reperfusion). The native thiols (-SH) and total thiols (-SH+ -SS) were determined. The amounts of disulfide (-SS), disulfide/native thiol percent ratios (-SS/-SH), disulfide/total thiol percent ratios (-SS/-SH+-SS), and native thiol/total thiol percent ratios (-SH/-SH+ -SS) were calculated.

Results

In the sevoflurane group, preoperative values and intraoperative 30th-minute SS-SH ratio were significantly reduced (p=0.017). In the desflurane group, intraoperative native thiol values and postdeflation levels significantly decreased compared to those in the preoperative values (p<0.001).

Conclusion

We think that the usage of sevoflurane was more protective in terms of the oxidative damage occurring during laparoscopic surgery.

Oxidative stress markers in laparoscopic vs. open appendectomy for acute appendicitis: A double-blind randomized study

BACKGROUND

Oxidative stress is a complicated process, which was defined as an increase in prooxidants and decrease in antioxidants caused by various mechanisms, including inflammation and surgical trauma. The association between acute appendicitis and oxidative stress has been showed in previous studies. However, comparison of oxidative stress in laparoscopic or open appendectomy (OA) has not been established.

PATIENTS AND METHODS

Patients who were diagnosed as acute appendicitis between October 2012 and January 2013 were randomized to open (OA, n = 50) and laparoscopic appendectomy (LA, n = 50). Blood samples for oxidative stress markers (total oxidant status [TOS] and total antioxidant status [TAS]), C-reactive protein (CRP) and white blood cells (WBC's) were collected just before the surgery and 24 h after surgery.

RESULTS

There were no differences in preoperative values of WBC and CRP between LA and OA groups (P = 0.523 and 0.424), however, in postoperative 24(th) h, CRP was reduced in LA group (P = 0.031). There were no differences in preoperative levels of TOS, TAS, and oxidative stress index (OSI) between LA and OA groups. In the postoperative 24(th) h, TOS and OSI were found to be significantly higher in OA group when compared to LA group (P = 0.017 and 0.002) whereas no difference was detected in TAS level in the postoperative 24(th) h (P = 0.172).

CONCLUSIONS

This double-blind, randomized clinical trial provides evidence that LA for uncomplicated appendicitis is associated with significantly lower oxidative stress compared with OA. Some of the advantages of LA may be attributed to the significant reduction of oxidative stress in these patients.

Effects of carbon dioxide pneumoperitoneum on postoperative adhesion formation and oxidative stress in a rat cecal abrasion model

INTRODUCTION

It is claimed that CO2 pneumoperitoneum (CP) is less adhesiogenic than laparotomy. Our aim in this study was to investigate the local oxidative stress responses and related adhesion formation resulting from exposure to CP.

METHODS

Forty-five rats were randomised into six groups. Group 1 underwent laparotomy only; in group 2, 6 mmHg CP was performed for 60 min; in group 3, the same procedure was carried out using 12 mmHg CP; in group 4, laparotomy and cecal-peritoneal abrasion were performed; in group 5, 6 mmHg CP was performed for 60 min, followed by laparotomy and cecal-peritoneal abrasion; in group 6, the same procedure was carried out using 12 mmHg CP. Groups 1, 2 and 3 were sacrificed immediately and used only for biochemical examination. The other groups were sacrificed on the 14th postoperative day.

RESULTS

The total adhesion scores, thickness, quantity, extent and type of adhesions decreased steadily in groups 4, 5 and 6 (p < 0.05). The median values for neutrophil and monocyte infiltration, and for capillary and fibroblast proliferation decreased steadily in groups 4, 5 and 6 (p < 0.05). CAT, SOD and GSHPx levels decreased significantly in line with increasing pressure in groups 1, 2 and 3. SOD and GSHPx levels were similar in groups 4, 5 and 6, while CAT levels decreased with increasing pressure in groups 4, 5 and 6.

CONCLUSION

It was found that CP is associated with less adhesion formation than laparotomy in the presence of similar antioxidant levels. The reduced adhesion formation is probably caused by a decreased inflammatory response.

Predisposing factors to post-operative adhesion development

BACKGROUND

Adhesion development is the most common sequelae of intra-abdominal and pelvic surgery and represents a significant, yet poorly understood, cause of morbidity among post-operative patients. It remains unclear, for example, exactly why adhesions form more frequently in certain tissues and/or patients, or at specific locations within them, as opposed to others. This review contributes to the growing knowledge pool by elucidating factors that potentially predispose to the development of adhesions. Given the strong correlation between a hypofibrinolytic state and adhesion formation, this review article will examine not only those factors that have been shown to directly predispose to adhesion development, but also those that are likely do so indirectly by means of altering the coagulation/fibrinolytic profile.

METHODS

A literature search was performed using the PubMed database for all relevant English language articles up to February 2014. All of the identified articles were reviewed with particular attention to predisposing factors to post-operative adhesion development. In addition, the reference lists of each article were reviewed to identify additional relevant articles.

RESULTS

Various factors have been shown to directly increase the risk of post-operative adhesion development; namely, certain genetic polymorphisms in the interleukin-1 receptor antagonist, increased estrogen exposure, and endometriosis. In addition, numerous factors are known to increase the risk of fibrosis, therefore likely increasing the risk of adhesion development indirectly. These factors include genetic polymorphisms in plasminogen activator inhibitor-1 and thrombin-activatable fibrinolysis inhibitor, diabetes mellitus, metabolic syndrome, hyperglycemia, obesity, depression, binge alcohol consumption, anti-Parkinsonian medications, oral hormone therapy, pregnancy, and cancer.

CONCLUSIONS

The literature reviewed in this paper will help to direct future research aimed at understanding the mechanisms that underlie the association of certain factors with adhesion development. This information will be crucial in the creation of adequate preventative and treatment strategies.

Oxidative stress in multi-port and single-port cholecystectomy

BACKGROUND

This study was designed to analyze and compare plasma levels of 8-isoprostane (8-epiPGF2α), a biomarker of lipid peroxidation, and uric acid (UA), a marker of the antioxidant status, in standard laparoscopic (LC) and laparoendoscopic single-site cholecystectomy (LSSC).

MATERIALS AND METHODS

Forty patients with noncomplicated cholelithiasis were randomized to undergo either LSSC (n = 20) or LC (n = 20). The patients had body mass index <30, American Society of Anesthesiologists score I or II, and no previous upper gastrointestinal surgery. Blood samples were taken preoperatively and 6 h and 24 h postoperatively. Levels of 8-epiPGF2α were determined using enzyme-linked immunosorbent assay, whereas levels of UA were calculated using automated analyzer.

RESULTS

No significant differences were observed in operative data among the groups. Levels of 8-epiPGF2α were significantly higher in LSSC compared with LC at 6 h (P = 0.003) and 24 h (P < 0.001). 8-epiPGF2α levels showed significant changes over time in LC (LSSC: P = 0.720, LC: P < 0.001). UA levels were significantly higher in LC compared with LSSC, 24 h postoperatively (P = 0.021). No significant changes over time in the UA levels in both groups (LSSC: P = 0.056, LC: P = 0.205).

CONCLUSIONS

LSSC is associated with increased oxidative stress compared with LC. Further studies are needed to confirm these results.

The effect of dexmedetomidine on oxidative stress during pneumoperitoneum

Purpose. This study was intended to investigate the effect of dexmedetomidine on oxidative stress response in pneumoperitoneum established in rats. Methods. Animals were randomized into three groups, group S: with no pneumoperitoneum, group P: with pneumoperitoneum established, and group D: given 100 mcg intraperitoneal dexmedetomidine 30 min before establishment of pneumoperitoneum. Plasma total oxidant status (TOS), total antioxidant status (TAS), and oxidative stress index (OSI) activity were measured 30 min after conclusion of pneumoperitoneum. Results. The mean TOS level was significantly higher in group P than in the other two groups, and the TOS level was significantly higher in group D than in group S (P < 0.05). Plasma TAS level was found to be lower in group P than in the other two groups, and the TAS level was lower in group D than in group S (P < 0.05). Consequently, the OSI was significantly higher in group P than in groups D and S (P < 0.05). Conclusions. Ischemia-reperfusion phenomenon that occurs during pneumoperitoneum causes oxidative stress and consumption of plasma antioxidants. Dexmedetomidine decreases oxidative stress caused by pneumoperitoneum and strengthens the antioxidant defense system.

Lipoic acid decreases peritoneal adhesion formation in a rat uterine scar model

OBJECTIVE

To investigate the effects of lipoic acid in the prevention of postoperative pelvic adhesions by a visual scoring system and immunohistochemistry in a rat uterine horn model with full thickness injury.

MATERIAL AND METHODS

Twenty-eight female Wistar albino rats were randomised into four groups: uterine trauma control, 15 days and 30 days, and uterine trauma + lipoic acid, 15 days and 30 days. A full thickness defect was established by incising a segment of approximately 1.0 cm in length from each uterine horn, leaving the mesometrium intact. Extension and severity of the adhesions in each group were scored by a visual scoring system and evaluated immunohistochemically.

RESULTS

Adhesion scores were 2.00±0.81, 2.14±0.69 0.71±0.75, and 0.85±0.69 for extent and 2.28±0.48, 2.14±0.69, 0.85±0.69, and 1.14±0.69 for severity in Groups 1, 2, 3 and 4, respectively. Adhesion extent and severity were significantly less for groups treated by lipoic acid but no difference was observed between long and short administration. Both Vitronectin and u-PAR staining were significantly increased in treatment groups when compared to the control group.

CONCLUSION

Lipoic acid was found to be effective in reducing postoperative adhesion formation in a rat model.

Effect of transgastric peritoneal access on peritoneal innate cellular immunity: experimental study in swine

BACKGROUND

One of the main concerns of natural orifice surgery is the local and systemic impact on physiology. Few studies have compared natural orifice transluminal endoscopic surgery (NOTES) with other surgical modalities. Most studies are based on systemic variables such as postoperative serum cytokines, with conflicting results. Surgical trauma induces an early inflammatory response, release of cytokines, and local leukocyte activation and oxidative burst. Major surgical trauma is related to impairment of phagocytic function and an increase in production of active oxygen species by phagocytes. The aim of this study was to evaluate the impact of transgastric peritoneoscopy on peritoneal innate immune response compared with laparoscopy and laparotomy in swine.

METHODS

Thirty-four male Sus scrofa domesticus swine were assigned to four groups: transgastric peritoneoscopy (13), laparoscopy (7), laparotomy (7), and sham procedure (7). Twenty-four hours after the procedure, peritoneal fluid cells were harvested by peritoneal washing after necropsy. Flow cytometry analysis of labeled S. aureus and E. coli phagocytosis by peritoneal neutrophils and macrophages was blindly performed. Oxidative burst activity measured by H(2)O(2) production under different challenges was also evaluated.

RESULTS

Total operative time varied between all groups. The transgastric, laparoscopy, and laparotomy groups required 56, 17.2, and 40.3 min of mean operative time, respectively (p < 0.05). Even though the mean percentage and intensity of phagocytosis by peritoneal phagocytes were higher in the sham, transgastric, and laparoscopy groups, there was no significant difference between these groups and laparotomy. Macrophage production of H(2)O(2) has been shown to be similar among the transgastric, laparoscopy, and sham groups, and smaller than that in laparotomy (p < 0.05), either under basal conditions, while performing E. coli phagocytosis, or challenged by the presence of E. coli membrane lipopolysaccharide.

CONCLUSION

Under the conditions of this study, transgastric peritoneoscopy has been shown to have minimal impact on peritoneal innate immune response.

Increased oxidative stress and gut ischemia caused by prolonged pneumoperitoneum in patients undergoing robot-assisted laparoscopic radical prostatectomy

OBJECTIVE

To investigate changes in plasma oxidative stress markers associated with prolonged pneumoperitoneum during robot-assisted laparoscopic radical prostatectomy (RALP).

METHODS

In all, patients of ASA Physical Status II-III who intended to undergo RALP were enrolled in the study. Arterial plasma levels of malondialdehyde (MDA) and intramucosal pH were measured 1 minute before and at 1 hour, 2 hours, 3 hours, and 4 hours after the introduction of pneumoperitoneum at an insufflation pressure of 15 mmHg; likewise, they were again measured every 10 minutes after deflation for 60 minutes, at 2 hours and 12 hours after deflation.

RESULTS

The mean duration of pneumoperitoneum was around 4 hours. After induction of pneumoperitoneum, the MDA concentrations were significantly elevated at various time points as compared with the preinsufflation value. Significant increase of MDA value was noted also 30 minutes after deflation as compared with the pre-deflation levels. The intramucosal pH value decreased significantly after CO(2) insufflation compared with the preinsufflation values. It also increased significantly 2 hours after CO(2) deflation as compared with the pre-deflation values.

CONCLUSION

A prolonged pneumoperitoneum in RALP results in decreased splanchnic blood flow. Pneumoperitoneum itself produces oxidative stress, and ischemia-reperfusion model after deflation of pneumoperitoneum produces more oxidative stress.

Antioxidant prophylaxis for cellular injury in ovarian surface epithelium resulting from CO₂ pneumoperitoneum in a laparoscopic rat model

OBJECTIVE

Selective cytoprotective functions of vitamin E, N-acetyl-L: -cysteine, and amifostine have been used as a preventer of ischemia injury by expelling the free oxygen radicals leading to stabilization of the cellular membranes. The purpose of this experimental study was to investigate the oxidative stress related to cellular injury in ovarian surface epithelium and the effect of prophylaxis with an anti-oxidant using laparoscopic rat model.

DESIGN

Laparoscopic rat model.

MATERIALS AND METHODS

Randomly allocated 40 Wistar Albino female rats have been used for the pneumoperitoneum model which was constituted to fix the intraabdominal pressure on 5 mmHg for 60 min. The antioxidants, vitamin E and NAC were given to rats 3 days before the operation and were applied for 30 days; amifostine was applied 30 min before the operation until after for 7 days. After abdominal desufflation, over biopsies were made on the 13th min, 24th h, and 7th and 30th days. By using of transmission electron microscopy, the damage on cells and organels were assessed and graded.

RESULTS

In ovarian surface epithelium, the apical surface specializations were affected in all groups except Vit E group:The microvilli were irregular and coarse and had disappeared in some places. Some cells were separated from the epithelium. In addition, mitochondria degeneration was observed in all group except Vit E.

CONCLUSIONS

In the early period of laparoscopy, reversible cellular damage occurs and this damage can be prevented by vitamin E.

Oxidative stress in laparoscopic versus open abdominal surgery: a systematic review

BACKGROUND

Any form of trauma, including surgery, is known to result in oxidative stress. Increased intra-abdominal pressure during pneumoperitoneum and inflation-deflation may cause ischemia reperfusion and, hence, oxidative stress may be greater during laparoscopic surgery. The aim of this study was to systemically review the literature to compare oxidative stress in laparoscopic and open procedures.

METHODS

A systematic search of the Medline, Pub Med, EMBASE, and Cochrane databases was performed with the following keywords: pneumoperitoneum AND surger $ OR laparoscop $ AND oxida $. The search was limited to articles published between 1980 and August 2010.

RESULTS

The initial search identified 197 papers. After review of the abstracts, 17 papers met the inclusion criteria. Six more papers were identified through the reference lists. It was not possible to perform a meta-analysis due to heterogeneity of patient data, patient selection criteria, and diversity of biomarkers used. The majority of studies demonstrated greater immediate oxidative stress after open surgery. There was, however, a paucity of studies comparing open versus laparoscopic surgery with regards to tissue oxidative stress.

CONCLUSION

Laparoscopic surgery seems to produce less systemic oxidative stress. However the effect of pneumoperitoneum on local oxidative stress and tissue hypoxia and its clinical significance need further investigation.

Efficacy of vitamin E and selenium for the prevention of intra-abdominal adhesions in rats: uterine horn models

OBJECTIVE

This study compares the efficacies of vitamin E and selenium, both individually and in combination, for the prevention of postoperative intra-abdominal adhesions in rats.

METHODS

Forty-seven female rats were divided into five groups. The sham animals (S group, n = 7) were given only laparotomies and intraperitoneally received 0.9% NaCl (2 ml). In the 40 other rats, abrasions of the left uterine horn were performed, followed by intraperitoneal administration of either 2 ml 0.9% NaCl (C group), 10 mg vitamin E (vitamin E group), 0.2 mg/kg selenium (Se group) or 10 mg vitamin E with 0.2 mg/kg selenium (vitamin E + Se group), with 10 animals in each treatment group.

RESULTS

Adhesion formation was significantly reduced in animals in the Se and vitamin E + Se groups (p<0.05). Tissue catalase and glutathione peroxidase activities did not significantly differ between the groups. However, catalase and glutathione peroxidase activities and reduced glutathione levels were slightly increased in the vitamin E, Se and vitamin E + Se groups. In the vitamin E group, malondialdehyde concentrations were significantly lower than in the C group (p<0.05), but no significant differences were present among the S, C, Se and vitamin E + Se groups. Levels of nitric oxide were significantly higher in the C group than in the other groups (p<0.01).

CONCLUSION

Intraperitoneal administration of selenium or combined vitamin E and selenium appears to be effective in preventing intra-abdominal adhesion formation in rat models through the reduction of lipid peroxidation products.

The influence of pre-emptive analgesia on postoperative analgesia and its objective evaluation

INTRODUCTION

The evaluation of pain intensity is still a subject of research. Mostly psychological evaluations are used. We started to conduct biochemical evaluation in animal experiments. Now we present biochemical evaluation in postoperative pain in man.

MATERIAL AND METHODS

In 67 patients herniotomy was done. For pre-emptive analgesia morphine and pethidine were used and the following indicators were measured: visual analogue scale (VAS), measurement of lipid spectra, saccharides and proteins, thioredoxin, super-oxide dismutase (SOD), glutathione peroxidase (GPx) and NAD(P)H-oxidase (NOX), and free radicals using electron paramagnetic resonance (EPR). Blood samples were taken and tested: before pre-medication and intervention, 4 h after and 24 h after intervention.

RESULTS

Free radicals (FR) increased in individual samples during the postoperative course in pethidine and without pre-medication. After application of morphine the FR were insignificantly reduced. Statistically significant differences were found in albumin, prealbumin, apolipoprotein A, total cholesterol, atherosclerotic index, CRP, glucose, and thioredoxin (p ≤ 0.001). A greater difference was seen in VAS values between morphine and pethidine premedications (p ≤ 0.001).

CONCLUSIONS

It was proved that the biochemical markers of lipid, protein and saccharide metabolisms and free radicals as well as singlet oxygen can serve as very good indicators of the intensity of pain and nociception. In patients it was proved that pre-emptive analgesia plays an important role in reducing the intensity of postoperative pain. From the three modalities of pre-emptive analgesia morphine represents the best solution.

The correlation between reactive oxygen species and histopathology of the liver, gut, and kidneys in animals with elevated intra-abdominal pressure

BACKGROUND

Clinical and experimental studies have shown that the laparoscopic procedure provides a typical model of ischemia-reperfusion injury in the organs by oxygen-derived free radicals. A pneumoperitoneum produces ischemia during insufflation and reperfusion during desufflation. The aim of this study was to assess the causative role of free radical-mediated reactions in tissue damage under different intra-abdominal insufflation pressures.

MATERIALS AND METHODS

Thirty five mature New Zealand white rabbits were assigned to three groups of 10 animals. In groups 1, 2, and 3, the designated pressures of 10, 15, and 20 mm Hg, respectively. The remaining 5 animals underwent laparotomy, using a 10-cm midline incision taken as group 4 (control). Blood samples were collected before (0 minutes) and at the end of the procedure (60 minutes). After the collection of the last blood samples, all animals were sacrificed and the samples from the liver, kidney, and gut were obtained for histologic evaluation and also measurements of tissue malondialdehyde (MDA) levels.

RESULTS

The nitric oxide levels were not changed in groups 1 and 2, but increased significantly in group 3. Tissue MDA levels were significantly higher in groups 1 and 2 than groups 3 and 4. Histopathologic examination of the kidney revealed some findings of reversible hypoxic cell injury, including acute cellular swelling, vascular congestion, and some early findings of irreversible injury, such as lysis of the cytoplasmic membrane in all groups and focal parancymal bleeding area in only group 3 as a consequence of increased pressure. Liver histology revealed cellular swelling and karyorhexis in hepatocytes in group 1, whereas only congestion and sinusoidal dilatation was observed in groups 2 and 3.

CONCLUSION

Our experimental study showed that abdominal insufflation causes ischemia and free radical production, which seems responsible for the cell damage that occured during laparoscopic surgery.

Systematic review of oxidative stress associated with pneumoperitoneum

Background

There have been several reports of ischaemic complications after routine laparoscopy. The aim of this review was to investigate the relationship between this oxidative stress and pneumoperitoneum.

Methods

Medline, Medline in-process, The Cochrane Library, PubMed and EMBASE were searched for papers on oxidative stress and pneumoperitoneum, from 1947 to March 2008 with no language restriction or restriction on trial design. Papers that did not investigate pneumoperitoneum as a causative factor, or did not report outcome measures related to oxidative stress, were excluded.

Results

A total of 73 relevant papers were identified: 36 animal studies, 21 human clinical trials, nine case reports, five review articles and two comments. Pneumoperitoneum causes a reduction in splanchnic blood flow, resulting in biochemical evidence of oxidative stress in a pressure- and time-dependent manner. There is evidence that the use of carbon dioxide for insufflation is contributory. Several measures proposed to minimize the oxidative stress have shown promise in animal studies, but few have been evaluated in the clinical setting.

Conclusion

There is an increasing body of evidence, mainly from animal studies, that pneumoperitoneum decreases splanchnic perfusion with resulting oxidative stress. It is now appropriate to investigate the clinical significance of pneumoperitoneum-associated oxidative stress.

Effects of adding small amounts of oxygen to a carbon dioxide-pneumoperitoneum of increasing pressure in rabbit ventilation models

OBJECTIVE

To evaluate the metabolic consequences of the addition of oxygen to the CO(2)-pneumoperitoneum.

DESIGN

Prospective randomized study in rabbits. After 30 minutes of ventilation pneumoperitoneum was maintained for 90 minutes with pure CO(2) or CO(2) with 2% or 6% of oxygen. The intraperitoneal pressure was increased from 10 to 15 and 20 mm Hg every 30 minutes. Ventilation rate was either fixed or a progressive hyperventilation. End points were changes in arterial blood gases (Pco(2), Po(2)), pH, acid-base balance (actual base excess [ABE], standard bicarbonate [SBC], standard base excess [SBE], hydrogen carbonate [HCO(3)(-)], concentration of total carbon dioxide [Tco(2)]); oxygen and oximetry (oxyhemoglobin [O(2)Hb], oxygen saturation [So(2)], reduced hemoglobin [RHb], total oxygen concentration [To(2)], and oxygen tension at half saturation assessing hemoglobin oxygen affinity [p50]); and lactate concentrations assayed every 15 minutes.

SETTING

University research center.

ANIMALS

Twenty-four adult female New Zealand white rabbits.

INTERVENTION(S)

Anesthesia, mechanical ventilation, and pneumoperitoneum.

RESULT(S)

The effects of CO(2)-pneumoperitoneum on all end points increased with the elevated intraperitoneal pressure and were more pronounced when ventilation was fixed. Changes were less when 2% or 6% of oxygen had been added to the CO(2)-pneumoperitoneum. With use of logistic regression, the addition of oxygen, intraperitoneal pressure, and ventilation were found to be independent variables affecting Pco(2), pH, ABE, SBE, HCO(3)(-), O(2)Hb, So(2), p50, and end-tidal CO(2).

CONCLUSION(S)

The metabolic consequences of the combined effect of increased intraperitoneal pressure and CO(2)-pneumoperitoneum were less when 2% to 6% of oxygen was added or when animals were hyperventilated. We suggest that metabolic and mesothelial hypoxemia caused by CO(2) absorption can be reduced by adding small amounts of oxygen and by hyperventilation.

Female infertility and free radicals: potential role in adhesions and endometriosis

Free radicals are highly reactive molecules produced in the cell either as part of, or as end-products of, biochemical reactions that have crucial roles in the homeostasis of the organism. Thus, excess production or impaired elimination of free radicals leads to increased oxidative stress, which has been implicated in the development of several different disease states, including hypoxia-reperfusion injury, cancer, and aging. Peritoneal adhesions and endometriosis are relatively commonly identified in women, and are known to be associated with infertility without clearly understood pathophysiology. The prevention and treatment strategies of these conditions, both of which have tremendous propensity to recur, have not been completely established. The development of both disorders has been shown to be closely related to the presence of increased oxidative stress in the tissues. In this article, we review this relationship with reference to the mechanistic steps involved and their regulation. As our knowledge of both conditions expands, we believe there will be opportunities for specific steps to intervention in free radical metabolism to reduce and/or prevent further development of endometriosis and adhesions.

The effects of increased intraabdominal pressure on testicular blood flow, oxidative stress markers, and morphology

BACKGROUND

This study was carried out to evaluate the effects of increased intraabdominal pressure (IAP) on testicular blood flow (TBF), oxidative stress markers, and morphology.

METHODS

Twenty-four Sprague-Dawley rats weighing 300 to 350 g were allocated randomly into 3 groups consisting of 8 animals each: A, gasless (control); B, 10 mm Hg IAP with CO(2) pneumoperitoneum for 60 minutes; and C, 20 mm Hg IAP with CO(2) pneumoperitoneum for 60 minutes. Testicular blood flow was studied using the Doppler technique. In the 10 and 20 mm Hg IAP groups, time points of TBF measurements were defined as follows: TBF(baseline), 10 minutes before insufflation; TBF(10min), 10 minutes after pneumoperitoneum; TBF(50min), 50 minutes after pneumoperitoneum; and TBF(reperfusion), 10 minutes after pneumoperitoneum deflation. To evaluate the changes in oxidative stress, we assayed the malondialdehyde (MDA) levels of testicular tissues. A 4-level grading scale was used to quantify histologic injury.

RESULTS

For both testes of each rat, TBF(10min), TBF(50min), and TBF(reperfusion) values of each group were separately evaluated according to their TBF(baseline) value percentages. The results revealed no significant differences for each time point of TBF measurements between the right and left testes in any group. Pneumoperitoneum caused a significant decrease in TBF at the 10th and 50th minutes of pneumoperitoneum, both in the 10 and 20 mm Hg IAP groups, compared with their baseline values. TBF(reperfusion) values in both groups were also lower than their baseline values. We determined that mean TBF(10min) and TBF(50min) values decreased significantly in the 20 mm Hg IAP group compared with the 10 mm Hg IAP group, despite there being no significant difference in their mean TBF(reperfusion) values. Mean MDA levels were significantly increased in both the 10 and 20 mm Hg IAP groups compared with those of the control group for the right and left testes. However, there was no significant difference between the mean MDA levels in these first 2 groups. The histologic injury score was significantly increased in both the 10 and 20 mm Hg IAP groups compared with the control group; however, there was no difference in the scores between these first 2 groups.

CONCLUSIONS

We demonstrated in an animal model that abdominal deflation after IAP of 10 and 20 mm Hg for 60 minutes causes testicular hypoperfusion, free radical production, and subsequent testicular damage.

Inflammatory response in children after laparoscopic vs open Nissen fundoplication: randomized controlled trial

We performed a randomized controlled trial to compare the inflammatory and immune responses to Nissen fundoplication in infants and children undergoing either open or laparoscopic surgery.

METHODS

Forty children undergoing Nissen fundoplication were randomized to laparoscopy or open surgery using minimization with respect to age, neurologic status, and operating surgeon. Intraoperative and postoperative analgesias were standardized. Inflammatory markers (plasma malondialdehyde, nitrate plus nitrite level, and cytokines) and monocyte class II major histocompatibility complex expression were measured preoperatively, at end of surgery, 4, 24, and 48 hours postoperatively. Postoperative changes were compared between open and laparoscopic groups.

RESULTS

There were no significant changes in circulating malondialdehyde, nitrates plus/ nitrite, interleukin-10, or tumor necrosis factor alpha in the postoperative period in either group. Interleukin-1 receptor antagonist (IL-1rA) and IL-6 were significantly increased in both groups, with a tendency for greater elevation of IL-1rA in the open group. Monocyte major histocompatibility complex expression fell significantly in both groups; however, this fall appeared to be slightly more marked in the open group.

CONCLUSIONS

The postoperative cytokine response is similar in children undergoing open and laparoscopic Nissen fundoplication. This trial indicates that laparoscopy may partly reduce postoperative immune suppression.

Does Prolonged Pneumoperitoneum Affect Oxidative Stress Compared with Open Surgical Procedures?

BACKGROUND AND PURPOSE

As laparoscopic surgery has evolved, it has become part of the urologic surgical armamentarium and is now used to perform more complex procedures. Carbon dioxide, used to create pneumoperitoneum, produces physiologic changes in various organs, including the kidneys. Such changes are associated with altered redox status because of the release of free radicals and changes in oxidative stress signals. It is unknown whether prolonged pneumoperitoneum is associated with an increase in oxidative stress compared with open surgery. The objective of this study was to compare oxidative stress in patients undergoing urologic laparoscopic and open operations.

PATIENTS AND METHODS

Urine samples were obtained immediately preoperatively, immediately postoperatively, and at 6 and 18 hours after surgery from 10 patients who underwent urologic laparoscopic surgery and 10 patients who underwent open surgery. Concentrations of the oxidative stress marker isoprostane (8- iso-prostaglandin F2a) were measured, and the results were analyzed with respect to clinical factors associated with the type of surgery.

RESULTS

Urinary isoprostane concentrations (mean +/- SEM) in the laparoscopic and open groups showed an increase immediately after surgery to 189.0 +/- 64.2% and 141.1 +/- 45.8% of the preoperative values, respectively. A decrease in isoprostane was subsequently observed in both groups at 6 hours postoperatively, with preoperative values restored at 18 hours postoperatively (126.3 +/- 19.7% and 89.5 +/- 55.9% at 6 and 18 hours, respectively, in the laparoscopic group and 130.7 +/- 41.6% and 88.7 +/- 20.4% at 6 and 18 hours, respectively, in the open-surgery group). Although in both groups the peak PGF 2a concentration was observed immediately (0 hours) postoperatively, no significant differences were observed between the groups at 0, 6, and 18 hours. In the laparoscopic-surgery group, the mean increase tended to be higher and the decrease to be less prolonged than in the open-surgery group.

CONCLUSION

Oxidative stress, as measured by urinary 8-iso-prostaglandin F2a, is produced by both laparoscopic and open urologic surgery. The findings of our nonrandomized study suggest a pattern of increased oxidative stress postoperatively with either type of surgery, with subsequent return almost to preoperative levels. Prolonged laparoscopic operative time did not affect oxidative stress levels.

Effect of adding more than 3% oxygen to carbon dioxide pneumoperitoneum on adhesion formation in a laparoscopic mouse model

OBJECTIVE

To investigate the effect of the addition of 3% or higher oxygen concentrations to the carbon dioxide (CO2) pneumoperitoneum.

DESIGN

Prospective, randomized trial.

SETTING

Academic research center.

ANIMAL(S)

Female Naval Medical Research Institute mice (n = 100).

INTERVENTION(S)

Sixty minutes of CO2 pneumoperitoneum with 0%, 3%, 6%, 9%, or 12% oxygen; induction of adhesions by the creation of standardized peritoneal lesions during laparoscopy.

MAIN OUTCOME MEASURE(S)

Adhesions were quantitatively and qualitatively scored after 7 days during laparotomy to determine [1] the effect of 60 minutes of CO2 pneumoperitoneum with 0%, 3%, 6%, 9%, or 12% oxygen on adhesion formation, and [2] the effect of duration of CO2 pneumoperitoneum and insufflation pressure on adhesion formation with the addition of 0%, 3%, and 12% oxygen.

RESULT(S)

Compared with a CO2 pneumoperitoneum with 3% oxygen, adhesion formation is greater when either no oxygen or more than 3% oxygen is added to the CO2 pneumoperitoneum. These effects persisted at higher insufflation pressures and longer duration of pneumoperitoneum, both known to increase adhesion formation with pure CO2.

CONCLUSION(S)

This study confirms that adhesion formation is decreased with the addition of 3% oxygen to the CO2 pneumoperitoneum. The addition of higher oxygen concentrations, however, is deleterious. Adhesions always increase with time and duration of the pneumoperitoneum.