Peritoneal air exposure elicits an intestinal inflammation resulting in postoperative ileus

Postoperative Gastrointestinal Dysfunction After Neuromuscular Blockade Reversal With Sugammadex Versus Cholinesterase Inhibitors in Patients Undergoing Gastrointestinal Surgery: A Systematic Review and Meta-Analysis

BACKGROUND

Postoperative gastrointestinal dysfunction (POGD) commonly occurs following gastrointestinal (GI) surgery and is associated with specific anesthetic agents. Cholinesterase inhibitors employed for reversing neuromuscular blockade have been implicated in development of POGD. Sugammadex, a novel reversal agent, is linked with reduced POGD. However, there is a lack of comprehensive comparative review between these agents regarding their impact on POGD following GI surgery. This study aims to systematically review the effects of sugammadex on POGD compared to cholinesterase inhibitors following GI surgery.

METHODS

MEDLINE, EMBASE, and CENTRAL were searched as of July 2022 to identify articles comparing sugammadex with cholinesterase inhibitors in patients undergoing gastrointestinal surgery, specifically in relation to POGD. Secondary endpoints included length of hospital stay, readmission rates, pulmonary complications, and postoperative morbidity.

RESULTS

From 198 citations, 2 randomized controlled trials (RCTs) and 3 retrospective cohorts with 717 patients receiving sugammadex and 812 patients receiving cholinesterase inhibitors were included. Significantly lower rates of prolonged postoperative ileus (OR .44, 95% CI .25-.77, P < .05, I2 = 56%, low certainty evidence) was observed with sugammadex. No significant difference in any other outcome was observed. Narrative review of readmission data demonstrated no significant difference.

CONCLUSION

The use of sugammadex following gastrointestinal surgery is associated with significantly lower rates of prolonged postoperative ileus compared to cholinesterase inhibitors. However, these do not translate into a significant reduction in length of stay, morbidity, or postoperative nausea and vomiting. Results are limited by the numer of studies included and missing data, more robust RCTs are needed before recommendations can be made.

Serum and Erythrocyte Antioxidant Defense in Colorectal Cancer Patients during Early Postoperative Period: Potential Modifiers and Impact on Clinical Outcomes

A better understanding of antioxidant status, its modifiers, and its effect on clinical outcomes in patients undergoing colorectal cancer surgery is needed for effective antioxidant-based interventions. The objectives of this cohort study were: to determine baseline serum (total antioxidant capacity (TAC) and ferric reducing antioxidant power (FRAP); n = 72) and erythrocyte (superoxide dismutase (SOD) and glutathione peroxidase (GPx); n = 47) antioxidant capacity and time-course during the 72 h postoperative period, to identify potential modifiers, and to establish impact on clinical outcomes. Older patients with comorbidities had lower baseline FRAP. TAC was inversely and SOD directly correlated with inflammatory markers. Cancer pathology affected GPx (lower in advanced and more aggressive cancers) and SOD (higher in advanced cancers). Surgical intervention induced a transient increase in FRAP and TAC with greater FRAP elevation in older, obese patients with several comorbidities. SOD activity significantly increased while GPx non-significantly decreased between 8 and 24 h post-incision. Poorer health status was associated with an increase in SOD and a decrease in GPx at 72 h. Clinical manifestation of postoperative ileus was preceded by decreased TAC at 24 h and an increase in SOD between 8 and 24 h and anastomotic leak was manifested by diminished SOD at 72 h compared to activities at 8 and 24 h. The time-frame between 8 and 24 h post-incision might be the most critical regarding oxidant/antioxidant balance and therefore the best suited for antioxidant-based intervention.

Beta-1 blocker reduces inflammation and preserves intestinal barrier function after open abdominal surgery

BACKGROUND

Open abdominal surgery is frequently related to excessive inflammation and a compromised intestinal barrier, leading to poor clinical outcomes. The administration of beta-1 blocker has been shown to effectively reduce inflammation and preserve intestinal barrier function in patients with sepsis, shock, or other critical illnesses. The underlying mechanism of these effects may be associated with the autonomic nervous system's activation via cholecystokinin receptors. This study aimed to investigate the effect of beta-1 blocker on systemic and local inflammatory responses and the intestinal barrier function in the context of open abdominal surgery.

METHODS

A rat model of open abdominal surgery was induced through peritoneal air exposure for 3 hours and treated via gavage with the beta-1 blocker, metoprolol, or saline. Cholecystokinin-receptor antagonists were administered before the metoprolol treatment. Peritoneal lavage fluid, serum, and tissues were collected 24 hours after surgery to determine systemic and local inflammation and intestinal integrity.

RESULTS

The intervention with metoprolol significantly reduced serum tumor necrosis factor-alpha and interleukin-6 (P < .05) and peritoneal interleukin-6 (P < .01) compared with those of animals treated with saline. The intestinal myeloperoxidase indicating the influx of neutrophils was also significantly prevented by the administration of metoprolol (P < .05). Above all, this intervention resulted in a significant decrease in serum D-lactate and intestinal fatty acid-binding protein, intestinal permeability, bacterial translocation, and Chiu's score for intestinal mucosa injury (P < .05). However, the anti-inflammatory and intestinal integrity protective effects of metoprolol were prevented by the blockage of cholecystokinin receptors (P < .05).

CONCLUSION

Our data indicate that beta-1 blocker reduces systemic and local inflammatory responses and preserves intestinal barrier function after open abdominal surgery through a mechanism that depends on cholecystokinin receptors. Clinically, these findings imply that perioperative intervention with a beta-1 blocker may be an effective new therapy to enhance recovery after open abdominal surgery.

Neophytadiene from Turbinaria ornata Suppresses LPS-Induced Inflammatory Response in RAW 264.7 Macrophages and Sprague Dawley Rats

This study investigates the mode of action of Neophytadiene (MT), a molecule isolated from a marine algae Turbinaria ornata in LPS-induced inflammation in both in vitro and in vivo conditions. Neophytadiene (25, 50, 100 μM/mL) was treated to LPS-stimulated RAW 264.7 macrophages cells to identify its anti-inflammatory potential by measuring the level of tumour necrosis factor (TNF-α) by enzyme-linked immunosorbent assay (ELISA) and nitric oxide (NO) using Griess reagent. The mRNA levels of inflammatory cytokines, interleukin (IL-6 and IL-10), and the protein expression of nuclear factor-κB (NF-κB) and inducible nitric oxide synthase (iNOS) were quantified by Western blot analysis. Subsequently, Neophytadiene (12, 25, 50 mg/kg b.wt/p.o) was pre-treated for 7 days to the experimental animals followed by LPS (10 mg/kg) injection interaperitonially. After LPS induction, blood was collected and the haematological parameters were analysed followed by isolation of heart tissue for biochemical molecular and histopathological analysis Neophytadiene significantly inhibited the NO production and inflammatory cytokines TNF-α, IL-6 and IL-10 both in in vitro and in vivo conditions. Further, the expression of TNF-α, IL1β, NF-κB, iNOS, PI3k/Akt and MAPK in the heart tissue was modulated by Neophytadiene significantly confirming the anti-inflammatory potential. Thus, the effect of Neophytadiene on LPS-induced cardiac injury can be attributed to its anti-inflammatory antioxidant and cardioprotective properties.

Animal Models for Functional Gastrointestinal Disorders

Functional gastrointestinal disorders (FGID), such as functional dyspepsia (FD) and irritable bowel syndrome (IBS) are characterized by chronic abdominal symptoms in the absence of an organic, metabolic or systemic cause that readily explains these complaints. Their pathophysiology is still not fully elucidated and animal models have been of great value to improve the understanding of the complex biological mechanisms. Over the last decades, many animal models have been developed to further unravel FGID pathophysiology and test drug efficacy. In the first part of this review, we focus on stress-related models, starting with the different perinatal stress models, including the stress of the dam, followed by a discussion on neonatal stress such as the maternal separation model. We also describe the most commonly used stress models in adult animals which brought valuable insights on the brain-gut axis in stress-related disorders. In the second part, we focus more on models studying peripheral, i.e., gastrointestinal, mechanisms, either induced by an infection or another inflammatory trigger. In this section, we also introduce more recent models developed around food-related metabolic disorders or food hypersensitivity and allergy. Finally, we introduce models mimicking FGID as a secondary effect of medical interventions and spontaneous models sharing characteristics of GI and anxiety-related disorders. The latter are powerful models for brain-gut axis dysfunction and bring new insights about FGID and their comorbidities such as anxiety and depression.

Critical Evaluation of Animal Models of Gastrointestinal Disorders

Preclinical research remains an important tool for discovery and validation of novel therapeutics for gastrointestinal disorders. While in vitro assays can be used to verify receptor-ligand interactions and test for structural activity of new compounds, only whole-animal studies can demonstrate drug efficacy within the gastrointestinal system. Most major gastrointestinal disorders have been modeled in animals; however the translational relevance of each model is not equal. The purpose of this chapter is to provide a critical evaluation of common animal models that are being used to develop pharmaceuticals for gastrointestinal disorders. For brevity, the models are presented for upper gastrointestinal disorders involving the esophagus, stomach, and small intestine and lower gastrointestinal disorders that focus on the colon. Particular emphasis is used to explain the face and construct validity of each model, and the limitations of each model, including data interpretation, are highlighted. This chapter does not evaluate models that rely on surgical or other non-pharmacological interventions for treatment.

Ginsenoside Rb1 protects the intestinal mucosal barrier following peritoneal air exposure

Ginsenoside Rb1 (GRb1), which is one of the main ingredients derived from Panax ginseng, has been widely used to treat various gastrointestinal disorders. The present study aimed to determine whether GRb1 was able to prevent intestinal mucosal barrier damage in rats following peritoneal air exposure for 3 h. GRb1 (5, 10, and 20 mg/kg) was orally administrated via gavage four times prior to and following surgery. Blood and terminal ileum were sampled 24 h following surgery. Levels of serum D-lactate (D-LA) were detected using an enzyme-linked immunosorbent assay kit. Intestinal permeability was assessed by determining the intestinal clearance of fluorescein isothiocyanate-dextran (FD4). Activity of intestinal myeloperoxidase was measured to assess intestinal inflammation, and intestinal histopathology was assessed by light microscopy. The results showed that GRb1 reduced the level of serum D-LA, intestinal clearance of FD4, and the activity of intestinal myeloperoxidase. Intestinal edema and inflammation were also ameliorated by GRb1, and the Chiu's scores employed for assessing intestinal mucosal damage were also reduced in the GRb1-treated peritoneal air exposure group. In addition, GRb1 induced a significant difference at 10 and 20 mg/kg, indicating a dose-dependent effect. The results of the present study suggest that GRb1 may be able to protect the intestinal mucosal barrier against damage induced by peritoneal air exposure, which may be associated with its anti-inflammatory action.

Chronic Kidney Disease Induced Intestinal Mucosal Barrier Damage Associated with Intestinal Oxidative Stress Injury

Background. To investigate whether intestinal mucosal barrier was damaged or not in chronic kidney disease progression and the status of oxidative stress. Methods. Rats were randomized into two groups: a control group and a uremia group. The uremia rat model was induced by 5/6 kidney resection. In postoperative weeks (POW) 4, 6, 8, and 10, eight rats were randomly selected from each group to prepare samples for assessing systemic inflammation, intestinal mucosal barrier changes, and the status of intestinal oxidative stress. Results. The uremia group presented an increase trend over time in the serum tumor necrosis factor-alpha, interleukin-6 (IL-6) and IL-10, serum D-lactate and diamine oxidase, and intestinal permeability, and these biomarkers were significantly higher than those in control group in POW 8 and/or 10. Chiu's scores in uremia group were also increased over time, especially in POW 8 and 10. Furthermore, the intestinal malondialdehyde, superoxide dismutase, and glutathione peroxidase levels were significantly higher in uremia group when compared with those in control group in POW 8 and/or 10. Conclusions. The advanced chronic kidney disease could induce intestinal mucosal barrier damage and further lead to systemic inflammation. The underlying mechanism may be associated with the intestinal oxidative stress injury.

High-fat enteral nutrition reduces intestinal mucosal barrier damage after peritoneal air exposure

BACKGROUND

Peritoneal air exposure is needed in open abdominal surgery, but long-time exposure could induce intestinal mucosal barrier dysfunction followed by many postoperative complications. High-fat enteral nutrition can ameliorate intestinal injury and improve intestinal function in many gastrointestinal diseases. In the present study, we investigated the effect of high-fat enteral nutrition on intestinal mucosal barrier after peritoneal air exposure and the underlying mechanism.

METHODS

Male adult rats were administrated saline, low-fat or high-fat enteral nutrition via gavage before and after peritoneal air exposure for 3 h. Rats undergoing anesthesia without laparotomy received saline as control. Twenty four hours after surgery, samples were collected to assess intestinal mucosal barrier changes in serum D-lactate levels, intestinal permeability, intestinal tight junction protein ZO-1 and occludin levels, and intestinal histopathology. The levels of malondialdehyde and the activity of superoxide dismutase in the ileum tissue were also measured to assess the status of intestinal oxidative stress.

RESULTS

High-fat enteral nutrition significantly decreased the serum D-lactate level and increased the intestinal tight junction protein ZO-1 level when compared to the group treated with low-fat enteral nutrition (P < 0.05). Meanwhile, histopathologic findings showed that the intestinal mucosal injury assessed by the Chiu's score and the intestinal epithelial tight junction were also improved much more in the high-fat enteral nutrition-treated group (P < 0.05). In addition, the intestinal malondialdehyde level was lower, and the intestinal superoxide dismutase activity was higher in the high-fat enteral nutrition-treated group than that in the low-fat enteral nutrition-treated group (P < 0.05).

CONCLUSIONS

These results suggest that high-fat enteral nutrition could reduce intestinal mucosal barrier damage after peritoneal air exposure, and the underlying mechanism may be associated with its antioxidative action. Perioperative administration of high-fat enteral nutrition may be a promising intervention to preserve intestinal mucosal barrier function in open abdominal surgery.

Is robotic-assisted radical cystectomy (RARC) with intracorporeal diversion becoming the new gold standard of care?

BACKGROUND

Totally intracorporeal robotic-assisted radical cystectomy (RARC) has perceived difficulties compared to open radical cystectomy (ORC). As the technique is increasingly adopted around the world, the benefits of RARC with intra- or extracorporeal urinary diversion or ORC for the patients are still unclear. In this article, we consider the current evidence for this issue.

METHODS

We assessed two questions through using expert opinion and the medical literature: (A) Is RARC better than ORC for removing the cancer surgery and outcome? (B) Is RARC better than ORC for the urinary diversion?

OUTCOMES

(A) RARC is better than ORC for shorter length of stay, blood loss and complication rates. (B) Intracorporeal orthotopic neobladder may have a significant physiological and surgical benefit to the patient recovery.

CONCLUSIONS

RARC with total intracorporeal reconstruction has potential benefits to the patient. We recommend that all surgeons document patient-related outcome measures, urodynamics and enhanced recovery protocols for cystectomy patients to help us understand the real improvements within bladder cancer surgery and reconstruction.

The effect of peritoneal air exposure on intestinal mucosal barrier

Background. Damage of the intestinal mucosa barrier may result in intestinal bacterial and endotoxin translocation, leading to local and systemic inflammation. The present study was designed to investigate whether peritoneal air exposure induces damage of intestinal mucosal barrier. Methods. Sprague-Dawley rats (weighing 210 to 230 g) were randomized into five groups (6/group): a control group, a sham group, and three exposure groups with peritoneal air exposure for 1, 2, and 3 h, respectively. At 24 h after surgery, blood and terminal ileum were sampled. The serum D-lactate levels were determined using an ELISA kit. The intestinal permeability was determined by measuring the intestinal clearance of FITC-dextran (FD4). The histopathological changes in terminal ileum were also assessed. Results. Compared with the controls, peritoneal air exposure caused an increase in both serum D-lactate level and intestinal FD4 clearance, which were proportional to the length of peritoneal air exposure and correlated to Chiu's scores, indices for intestinal mucosal injury. Edema and inflammatory cells were also observed in mucosa and submucosa of ileum in three exposure groups. Conclusions. Peritoneal air exposure could induce damage to the intestinal mucosal barrier, which is proportional to the time length of peritoneal air exposure.