Postoperative ileus after digestive surgery: Network meta-analysis of pharmacological intervention

AIMS

Several medicinal treatments for avoiding postoperative ileus (POI) after abdominal surgery have been evaluated in randomized controlled trials (RCTs). This network meta-analysis aimed to explore the relative effectiveness of these different treatments on ileus outcome measures.

METHODS

A systematic literature review was performed to identify RCTs comparing treatments for POI following abdominal surgery. A Bayesian network meta-analysis was performed. Direct and indirect comparisons of all regimens were simultaneously compared using random-effects network meta-analysis.

RESULTS

A total of 38 RCTs were included in this network meta-analysis reporting on 6371 patients. Our network meta-analysis shows that prokinetics significantly reduce the duration of first gas (mean difference [MD] = 16 h; credible interval -30, -3.1; surface under the cumulative ranking curve [SUCRA] 0.418), duration of first bowel movements (MD = 25 h; credible interval -39, -11; SUCRA 0.25) and duration of postoperative hospitalization (MD -1.9 h; credible interval -3.8, -0.040; SUCRA 0.34). Opioid antagonists are the only treatment that significantly improve the duration of food recovery (MD -19 h; credible interval -26, -14; SUCRA 0.163).

CONCLUSION

Based on our meta-analysis, the 2 most consistent pharmacological treatments able to effectively reduce POI after abdominal surgery are prokinetics and opioid antagonists. The absence of clear superiority of 1 treatment over another highlights the limits of the pharmacological principles available.

Efficacy of Naldemedine on Intestinal Hypomotility and Adhesions in Rodent Models of Postoperative Ileus

Postoperative ileus (POI) often decreases patients' QOL because of prolonged hospitalization and readmission. Alvimopan, a peripheral μ-opioid receptor antagonist, is currently the only therapeutic drug for POI. The aim of this study was to examine the efficacy of naldemedine (a peripheral μ-opioid receptor antagonist with a non-competitive pharmacological profile different from that of alvimopan) on postoperative intestinal hypomotility and adhesion in rodent models, and compare it with the effects of alvimopan. Oral administration of naldemedine (0.3 mg/kg) and alvimopan (3 mg/kg) significantly inhibited the decrease in intestinal motility induced by mechanical irritation in mice (p < 0.01, for both). Naldemedine (1 mg/kg) significantly shortened the adhesion length in chemical-induced postoperative adhesion model rats (p < 0.05). Alvimopan (3 mg/kg) also significantly reduced the adhesion ratio (p < 0.01). These findings suggest that naldemedine is effective for postoperative intestinal hypomotility and adhesions in rodents (i.e., as for alvimopan). Thus, naldemedine may be a useful option for the treatment of POI.

Fuzapladib reduces postsurgical inflammation in the intestinal muscularis externa

Postoperative ileus (POI) is a surgical complication that induces emesis and anorexia. Fuzapladib (FUZ), an inhibitor of leukocyte-function-associated antigen type 1 (LFA-1) activation, a leukocyte adhesion molecule, exerts anti-inflammatory effects by inhibiting leukocyte migration into the inflammatory site. In this study, we examined the prophylactic impact of FUZ on POI in a mouse model. POI model mice were generated by intestinal manipulation, and the effect of FUZ on intestinal transit and the infiltration of inflammatory cells into the ileal muscularis externa was assessed. The increased number of macrophages was significantly suppressed by FUZ, whereas the infiltration of neutrophils into the ileal muscularis externa was not sufficiently inhibited in the POI model mice. Additionally, FUZ did not ameliorate delayed gastrointestinal transit in POI model mice. In conclusion, our results suggest that FUZ does not improve delayed gastrointestinal transit but partially inhibits inflammation in the ileal muscularis externa in POI model mice. FUZ may be a potential anti-inflammatory agent for the management of post-surgical inflammation.

Phlorizin attenuates postoperative gastric ileus in rats

BACKGROUND

Postoperative ileus (POI) is a major complication of abdominal surgery (AS). Impaired gut barrier mediated via Toll-like receptor 4 (TLR4) and interleukin-1 (IL-1) receptor is involved in the development of POI. Phlorizin is a nonselective inhibitor of sodium-linked glucose transporters (SGLTs) and is known to improve lipopolysaccharide (LPS)-induced impaired gut barrier. This study aimed to clarify our hypothesis that AS-induced gastric ileus is mediated via TLR4 and IL-1 signaling, and phlorizin improves the ileus.

METHODS

AS consisted of a celiotomy and manipulation of the cecum for 1 min. Gastric emptying (GE) in 20 min with liquid meal was determined 3 h after the surgery in rats. The effect of subcutaneous (s.c.) injection of LPS (1 mg kg-1 ) was also determined 3 h postinjection.

KEY RESULTS

AS delayed GE, which was blocked by TAK-242, an inhibitor of TLR4 signaling and anakinra, an IL-1 receptor antagonist. LPS delayed GE, which was also mediated via TLR4 and IL-1 receptor. Phlorizin (80 mg kg-1 , s.c.) significantly improved delayed GE induced by both AS and LPS. However, intragastrical (i.g.) administration of phlorizin did not alter it. As gut mainly expresses SGLT1, SGLT2 may not be inhibited by i.g. phlorizin. The effect of phlorizin was blocked by ghrelin receptor antagonist in the LPS model.

CONCLUSIONS & INFERENCES

AS-induced gastric ileus is mediated via TLR4 and IL-1 signaling, which is simulated by LPS. Phlorizin improves the gastric ileus via activation of ghrelin signaling, possibly by inhibition of SGLT2. Phlorizin may be useful for the treatment of POI.

BQ788 reveals glial ETB receptor modulation of neuronal cholinergic and nitrergic pathways to inhibit intestinal motility: Linked to postoperative ileus

BACKGROUND AND PURPOSE

ET-1 signalling modulates intestinal motility and inflammation, but the role of ET-1/ETB receptor signalling is poorly understood. Enteric glia modulate normal motility and inflammation. We investigated whether glial ETB signalling regulates neural-motor pathways of intestinal motility and inflammation.

EXPERIMENTAL APPROACH

We studied ETB signalling using: ETB drugs (ET-1, SaTX, BQ788), activity-dependent stimulation of neurons (high K+ -depolarization, EFS), gliotoxins, Tg (Ednrb-EGFP)EP59Gsat/Mmucd mice, cell-specific mRNA in Sox10CreERT2 ;Rpl22-HAflx or ChATCre ;Rpl22-HAflx mice, Sox10CreERT2 ::GCaMP5g-tdT, Wnt1Cre2 ::GCaMP5g-tdT mice, muscle tension recordings, fluid-induced peristalsis, ET-1 expression, qPCR, western blots, 3-D LSM-immunofluorescence co-labelling studies in LMMP-CM and a postoperative ileus (POI) model of intestinal inflammation.

KEY RESULTS

In the muscularis externa ETB receptor is expressed exclusively in glia. ET-1 is expressed in RiboTag (ChAT)-neurons, isolated ganglia and intra-ganglionic varicose-nerve fibres co-labelled with peripherin or SP. ET-1 release provides activity-dependent glial ETB receptor modulation of Ca2+ waves in neural evoked glial responses. BQ788 reveals amplification of glial and neuronal Ca2+ responses and excitatory cholinergic contractions, sensitive to L-NAME. Gliotoxins disrupt SaTX-induced glial-Ca2+ waves and prevent BQ788 amplification of contractions. The ETB receptor is linked to inhibition of contractions and peristalsis. Inflammation causes glial ETB up-regulation, SaTX-hypersensitivity and glial amplification of ETB signalling. In vivo BQ788 (i.p., 1 mg·kg-1 ) attenuates intestinal inflammation in POI.

CONCLUSION AND IMPLICATIONS

Enteric glial ET-1/ETB signalling provides dual modulation of neural-motor circuits to inhibit motility. It inhibits excitatory cholinergic and stimulates inhibitory nitrergic motor pathways. Amplification of glial ETB receptors is linked to muscularis externa inflammation and possibly pathogenic mechanisms of POI.

Targeting TRPV1 and TRPA1: A feasible strategy for natural herbal medicines to combat postoperative ileus

Under physiological or pathological conditions, transient receptor potential (TRP) channel vanilloid type 1 (TRPV1) and TRP ankyrin 1 (TRPA1) possess the ability to detect a vast array of stimuli and execute diverse functions. Interestingly, increasing works have reported that activation of TRPV1 and TRPA1 could also be beneficial for ameliorating postoperative ileus (POI). Increasing research has revealed that the gastrointestinal (GI) tract is rich in TRPV1/TRPA1, which can be stimulated by capsaicin, allicin and other compounds. This activation stimulates a variety of neurotransmitters, leading to increased intestinal motility and providing protective effects against GI injury. POI is the most common emergent complication following abdominal and pelvic surgery, and is characterized by postoperative bowel dysfunction, pain, and inflammatory responses. It is noteworthy that natural herbs are gradually gaining recognition as a potential therapeutic option for POI due to the lack of effective pharmacological interventions. Therefore, the focus of this paper is on the TRPV1/TRPA1 channel, and an analysis and summary of the processes and mechanism by which natural herbs activate TRPV1/TRPA1 to enhance GI motility and relieve pain are provided, which will lay the foundation for the development of natural herb treatments for this disease.

Preoperative combined mechanical and oral antibiotic bowel preparation for preventing complications in elective colorectal surgery

BACKGROUND

The success of elective colorectal surgery is mainly influenced by the surgical procedure and postoperative complications. The most serious complications include anastomotic leakages and surgical site infections (SSI)s, which can lead to prolonged recovery with impaired long-term health.  Compared with other abdominal procedures, colorectal resections have an increased risk of adverse events due to the physiological bacterial colonisation of the large bowel. Preoperative bowel preparation is used to remove faeces from the bowel lumen and reduce bacterial colonisation. This bowel preparation can be performed mechanically and/or with oral antibiotics. While mechanical bowel preparation alone is not beneficial, the benefits and harms of combined mechanical and oral antibiotic bowel preparation is still unclear.

OBJECTIVES

To assess the evidence for the use of combined mechanical and oral antibiotic bowel preparation for preventing complications in elective colorectal surgery.

SEARCH METHODS

We searched MEDLINE, Embase, CENTRAL and trial registries on 15 December 2021. In addition, we searched reference lists and contacted colorectal surgery organisations.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of adult participants undergoing elective colorectal surgery comparing combined mechanical and oral antibiotic bowel preparation (MBP+oAB) with either MBP alone, oAB alone, or no bowel preparation (nBP). We excluded studies in which no perioperative intravenous antibiotic prophylaxis was given.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures as recommended by Cochrane. Pooled results were reported as mean difference (MD) or risk ratio (RR) and 95 % confidence intervals (CIs) using the Mantel-Haenszel method. The certainty of the evidence was assessed with GRADE.

MAIN RESULTS

We included 21 RCTs analysing 5264 participants who underwent elective colorectal surgery. None of the included studies had a high risk of bias, but two-thirds of the included studies raised some concerns. This was mainly due to the lack of a predefined analysis plan or missing information about the randomisation process. Most included studies investigated both colon and rectal resections due to malignant and benign surgical indications. For MBP as well as oAB, the included studies used different regimens in terms of agent(s), dosage and timing.  Data for all predefined outcomes could be extracted from the included studies. However, only four studies reported on side effects of bowel preparation, and none recorded the occurrence of adverse effects such as dehydration, electrolyte imbalances or the need to discontinue the intervention due to side effects. Seventeen trials compared MBP+oAB with sole MBP. The incidence of SSI could be reduced through MBP+oAB by 44% (RR 0.56, 95% CI 0.42 to 0.74; 3917 participants from 16 studies; moderate-certainty evidence) and the risk of anastomotic leakage could be reduced by 40% (RR 0.60, 95% CI 0.36 to 0.99; 2356 participants from 10 studies; moderate-certainty evidence). No difference between the two comparison groups was found with regard to mortality (RR 0.87, 95% CI 0.27 to 2.82; 639 participants from 3 studies; moderate-certainty evidence), the incidence of postoperative ileus (RR 0.89, 95% CI 0.59 to 1.32; 2013 participants from 6 studies, low-certainty of evidence) and length of hospital stay (MD -0.19, 95% CI -1.81 to 1.44; 621 participants from 3 studies; moderate-certainty evidence). Three trials compared MBP+oAB with sole oAB. No difference was demonstrated between the two treatment alternatives in terms of SSI (RR 0.87, 95% CI 0.34 to 2.21; 960 participants from 3 studies; very low-certainty evidence), anastomotic leakage (RR 0.84, 95% CI 0.21 to 3.45; 960 participants from 3 studies; low-certainty evidence), mortality (RR 1.02, 95% CI 0.30 to 3.50; 709 participants from 2 studies; low-certainty evidence), incidence of postoperative ileus (RR 1.25, 95% CI 0.68 to 2.33; 709 participants from 2 studies; low-certainty evidence) or length of hospital stay (MD 0.1 respectively 0.2, 95% CI -0.68 to 1.08; data from 2 studies; moderate-certainty evidence). One trial (396 participants) compared MBP+oAB versus nBP. The evidence is uncertain about the effect of MBP+oAB on the incidence of SSI as well as mortality (RR 0.63, 95% CI 0.33 to 1.23 respectively RR 0.20, 95% CI 0.01 to 4.22; low-certainty evidence), while no effect on the risk of anastomotic leakages (RR 0.89, 95% CI 0.33 to 2.42; low-certainty evidence), the incidence of postoperative ileus (RR 1.18, 95% CI 0.77 to 1.81; low-certainty evidence) or the length of hospital stay (MD 0.1, 95% CI -0.8 to 1; low-certainty evidence) could be demonstrated.

AUTHORS' CONCLUSIONS

Based on moderate-certainty evidence, our results suggest that MBP+oAB is probably more effective than MBP alone in preventing postoperative complications. In particular, with respect to our primary outcomes, SSI and anastomotic leakage, a lower incidence was demonstrated using MBP+oAB. Whether oAB alone is actually equivalent to MBP+oAB, or leads to a reduction or increase in the risk of postoperative complications, cannot be clarified in light of the low- to very low-certainty evidence. Similarly, it remains unclear whether omitting preoperative bowel preparation leads to an increase in the risk of postoperative complications due to limited evidence. Additional RCTs, particularly on the comparisons of MBP+oAB versus oAB alone or nBP, are needed to assess the impact of oAB alone or nBP compared with MBP+oAB on postoperative complications and to improve confidence in the estimated effect. In addition, RCTs focusing on subgroups (e.g. in relation to type and location of colon resections) or reporting side effects of the intervention are needed to determine the most effective approach of preoperative bowel preparation.

Oral Antibiotic Bowel Preparation Prior to Urgent Colectomy Reduces Odds of Organ Space Surgical Site Infections: a NSQIP Propensity-Score Matched Study

BACKGROUND

Preoperative administration of oral antibiotic bowel preparation (OABP) alone has been shown to reduce infectious outcomes in patients undergoing elective colectomy. However, it remains unclear if these benefits extend to the emergency setting. This is a retrospective, propensity-score matched study comparing 30-day perioperative morbidity between those who received OABP alone versus no preparation prior to urgent colectomy.

METHODS

Using the American College of Surgeons National Surgical Quality Improvement Program database, adults undergoing urgent colectomy from 2012 to 2019 were included. Those who were clinically obstructed or who received mechanical bowel preparation were excluded. Outcomes of interest included: surgical site infection (SSI), leak, ileus, and major morbidity.

RESULTS

Of 24,559 patients meeting inclusion criteria, 878 (3.6%) received OABP prior to urgent colectomy. Prior to matching, those receiving no preparation were more likely to have higher ASA class, diabetes, hypertension, preoperative sepsis, open procedures, and a dirty wound classification. After matching, 1756 patients, remained with 878 in each arm. Preoperative characteristics were balanced on univariate analysis. Postoperatively, patients receiving OABP experienced decreased organ space SSI (11.2% vs. 15.5%, p = 0.009) and ileus (30.3% vs. 35.3%, p = 0.029), with no difference in leak rates (3.3% vs 3.3%, p = 1.000) or NSQIP major morbidity (47.4% vs. 49.9%, p = 0.316). On multivariate logistic regression, including propensity score, the reduction in organ space SSI associated with OABP persisted (OR 0.684, 95% CI 0.516-0.903).

CONCLUSION

OABP prior to select urgent colectomies was associated with fewer organ space SSIs and may be considered when feasible.

A comparison of naloxegol versus alvimopan at the time of cystectomy and urinary diversion

INTRODUCTION

The use of alvimopan at the time of cystectomy has been associated with improved perioperative outcomes. Naloxegol is a less costly alternative that has been used in some centers. This study aims to compare the perioperative outcomes of patients undergoing cystectomy with urinary diversion who receive the mu-opioid antagonist alvimopan versus naloxegol.

MATERIALS AND METHODS

This was a retrospective review that included all patients who underwent cystectomy with urinary diversion at our institution between 2007-2020. Comparisons were made between patients who received perioperative alvimopan, naloxegol and no mu-opioid antagonist (controls).

RESULTS

In 715 patients who underwent cystectomy, 335 received a perioperative mu-opioid antagonist, of whom 57 received naloxegol. Control patients, compared to naloxegol and alvimopan patients, experienced a significantly (p < 0.05) delayed return of bowel function (4.3 vs. 2.5 vs. 3.0 days) and longer hospital length of stay (7.9 vs. 7.5 vs. 6.5 days), respectively. The incidence of nasogastric tube use (14.2% vs. 12.5% vs. 6.5%) and postoperative ileus (21.6% vs. 21.1% vs. 13.3%) was also most common in the control group compared to the naloxegol and alvimopan cohorts, respectively. A multivariable analysis revealed that when comparing naloxegol and alvimopan, there was no difference in return of bowel function (OR 0.88, p = 0.17), incidence of postoperative ileus (OR 1.60, p = 0.44), or hospital readmission (OR 1.22, p = 0.63).

CONCLUSIONS

Naloxegol expedites the return of bowel function to the same degree as alvimopan in cystectomy patients. Given the lower cost of naloxegol, this agent may be a preferable alternative to alvimopan.

Effect of prucalopride to improve time to gut function recovery following elective colorectal surgery: randomized clinical trial

BACKGROUND

Delayed return to gut function and prolonged postoperative ileus (PPOI) delay recovery after colorectal surgery. Prucalopride is a selective serotonin-4-receptor agonist that may improve gut motility.

METHODS

This was a multicentre, double-blind, parallel, placebo-controlled randomized trial of 2 mg prucalopride versus placebo in patients undergoing elective colorectal resection. Patients with inflammatory bowel disease and planned ileostomy formation were excluded, but colostomy formation was allowed. The study medication was given 2 h before surgery and daily for up to 6 days after operation. The aim was to determine whether prucalopride improved return of gut function and reduced the incidence of PPOI. The primary endpoint was time to passage of stool and tolerance of diet (GI-2). Participants were allocated in a 1 : 1 ratio, in blocks of 10. Randomization was computer-generated. All study personnel, medical staff, and patients were blinded.

RESULTS

This study was completed between October 2017 and May 2020 at two tertiary hospitals in New Zealand. A total of 148 patients were randomized, 74 per arm. Demographic data were similar in the two groups. There was no difference in median time to GI-2 between prucalopride and placebo groups: 3.5 (i.q.r. 2-5) versus 4 (3-5) days respectively (P = 0.124). Prucalopride improved the median time to passage of stool (3 versus 4 days; P = 0.027) but not time to tolerance of diet (2 versus 2 days; P = 0.669) or median duration of hospital stay (4 versus 4 days; P = 0.929). In patients who underwent laparoscopic surgery (125, 84.5 per cent), prucalopride improved median time to GI-2: 3 (2-4) days versus 4 (3-5) days for placebo (P = 0.012). The rate of PPOI, complications, and adverse events was similar in the two groups.

CONCLUSION

Prucalopride did not improve time to overall recovery of gut function after elective colorectal surgery. Registration number: NCT02947269 (http://www.clinicaltrials.gov).

Purinergic P2X7 receptor antagonist ameliorates intestinal inflammation in postoperative ileus

Postoperative ileus (POI) is a postsurgical gastrointestinal motility dysfunction caused by mechanical stress to the intestine during abdominal surgery. POI leads to nausea and vomiting reduced patient quality of life, as well as high medical costs and extended hospitalization. Intestinal inflammation caused by macrophages and neutrophils is thought to be important in the mechanism of POI. Surgery-associated tissue injury and inflammation induce the release of adenosine triphosphate (ATP) from injured cells. Released ATP binds the purinergic P2X7 receptor (P2X7R) expressed on inflammatory cells, inducing the secretion of inflammatory mediators. P2X7R antagonists are thought to be important mediators of the first step in the inflammation process, and studies in chemically induced colitis models confirmed that P2X7R antagonists exhibit anti-inflammatory effects. Therefore, we hypothesized that P2X7R plays an important role in POI. POI models were generated from C57BL/6J mice. Mice were treated with P2X7R antagonist A438079 (34 mg/kg) 30 min before and 2 hr after intestinal manipulation (IM). Inflammatory cell infiltration and gastrointestinal transit were measured. A438079 ameliorated macrophage and neutrophil infiltration in the POI model. Impaired intestinal transit improved following A438079 treatment. P2X7R was expressed on both infiltrating and resident macrophages in the inflamed ileal muscle layer. The P2X7R antagonist A438079 exhibits anti-inflammatory effects via P2X7R expressed on macrophages and therefore could be a target in the treatment of POI.

Safety and efficacy of non-steroidal anti-inflammatory drugs to reduce ileus after colorectal surgery

BACKGROUND

Ileus is common after elective colorectal surgery, and is associated with increased adverse events and prolonged hospital stay. The aim was to assess the role of non-steroidal anti-inflammatory drugs (NSAIDs) for reducing ileus after surgery.

METHODS

A prospective multicentre cohort study was delivered by an international, student- and trainee-led collaborative group. Adult patients undergoing elective colorectal resection between January and April 2018 were included. The primary outcome was time to gastrointestinal recovery, measured using a composite measure of bowel function and tolerance to oral intake. The impact of NSAIDs was explored using Cox regression analyses, including the results of a centre-specific survey of compliance to enhanced recovery principles. Secondary safety outcomes included anastomotic leak rate and acute kidney injury.

RESULTS

A total of 4164 patients were included, with a median age of 68 (i.q.r. 57-75) years (54·9 per cent men). Some 1153 (27·7 per cent) received NSAIDs on postoperative days 1-3, of whom 1061 (92·0 per cent) received non-selective cyclo-oxygenase inhibitors. After adjustment for baseline differences, the mean time to gastrointestinal recovery did not differ significantly between patients who received NSAIDs and those who did not (4·6 versus 4·8 days; hazard ratio 1·04, 95 per cent c.i. 0·96 to 1·12; P = 0·360). There were no significant differences in anastomotic leak rate (5·4 versus 4·6 per cent; P = 0·349) or acute kidney injury (14·3 versus 13·8 per cent; P = 0·666) between the groups. Significantly fewer patients receiving NSAIDs required strong opioid analgesia (35·3 versus 56·7 per cent; P < 0·001).

CONCLUSION

NSAIDs did not reduce the time for gastrointestinal recovery after colorectal surgery, but they were safe and associated with reduced postoperative opioid requirement.

Alvimopan, Regardless of Ileus Risk, Significantly Impacts Ileus, Length of Stay, and Readmission After Intestinal Surgery

BACKGROUND

Previous analyses evaluating alvimopan included patients at varying risk for ileus after intestinal resection, which may have precluded its widespread adoption. We assess the early and delayed effects of alvimopan in patients stratified by risk for ileus after intestinal and colon resection.

METHODS

From the Premier Perspective database, patients with elective small and large bowel resections from 2012 to 2014 were identified. Multivariable analysis identified 14 perioperative risk factors for postoperative ileus. Within low- (0-4 factors), intermediate- (5 factors), and high-risk (6-12 factors) ileus categories, alvimopan and no-alvimopan patients were propensity-score matched for demographics, morbidities, diagnosis, surgery and approach, postoperative complications, surgeon specialty, and hospital features. In-hospital postoperative ileus, length of stay, discharge destination, and ileus-related readmission were compared.

RESULTS

Of 52,948 patients, 15,719 (29.7%) received alvimopan. Risk for ileus in low- (18,784), intermediate- (14,370), and high-risk (19,794) categories was 8.9, 13, and 22% (p ≤ .0001) respectively. After matching, alvimopan was associated with significantly reduced in-hospital postoperative ileus in all (low, 6%; intermediate, 9.4%; and high risk, 16.2%) categories. Hospital stay and 30-, 60-, and 90-day postdischarge ileus were also significantly lower with alvimopan. For low-risk patients, alvimopan increased discharge to home, while 90-day emergency readmission was reduced.

CONCLUSIONS

Alvimopan, regardless of ileus risk, improves ileus, hospital stay, and ileus-related readmission after intestinal resection and these effects are sustained over the long term. Since fewer than a third of patients currently receive alvimopan, its routine adoption with small and large intestinal resection will significantly impact patients and health systems.

The effect of somatostatin retained enema in the treatment of pancreatic ileus

OBJECTIVE

To analyze the therapeutic effects of somatostatin retained enema in the treatment of pancreatic ileus in the clinic.

PATIENTS AND METHODS

79 patients randomly divided into 41 cases in the observation group and 38 cases in the control group were analyzed. The control group applied basic treatment plan. The observational group applied the same treatment combined with somatostatin retained enema, conducted twice every day and at least 30 minutes every time. Every 7 days' treatment made a course. The clinical therapeutic effects were compared.

RESULTS

The levels of the hemo diastase and urinary amylase in both groups were decreased prominently after treatment. The levels of blood calcium were prominently increased (p<0.05) with even more improvement in the observation group (p<0.05). The relief times of the abdominal ache and distention, the recovery time of bowel sound and the first defecation time in the observation group were shorter (p<0.05) than those in the control group. The levels of blood serum IL-6 and TNF-α in the two groups were prominently decreased (p<0.05) after treatment, with even more obvious improvement in the observation group. The therapeutic effective rate of the observational group was prominently higher (p<0.05) than that in the control group. The occurrence rate of the complications was lower.

CONCLUSIONS

The application of somatostatin retained enema in the treatment of pancreatic ileus is preferably safe and effective, and it deserves clinical promotion and application.

Alvimopan for recovery of bowel function after radical cystectomy

BACKGROUND

Alvimopan is used in abdominal surgery to reduce postoperative ileus in patients undergoing small bowel resections with primary anastomosis. The role and efficacy of alvimopan in patients undergoing radical cystectomy with urinary diversion is not well understood.

OBJECTIVES

To assess the effects of alvimopan in the context of enhanced recovery pathways compared to enhanced recovery pathways alone for perioperative bowel dysfunction in patients undergoing radical cystectomy.

SEARCH METHODS

The terms alvimopan and cystectomy were used to search the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Embase. We also reviewed abstracts from the past four years (2013 to 2016) of the American Urologic Association, Society of Urologic Oncology, and American Society of Clinical Oncology Genitourinary Cancers.

SELECTION CRITERIA

We searched for randomized controlled trials that compared alvimopan to placebo.

DATA COLLECTION AND ANALYSIS

This study was based on a published protocol. We performed a comprehensive search of multiple databases including CENTRAL in the Cochrane Library, MEDLINE, Embase, LILACS, Web of Science, Scopus and Biosis, which we last updated on 6 February 2017. We also searched abstract proceedings for major relevant meetings (2013 to 2016), databases of the grey literature, trial registries, citations of relevant reviews and contacted clinical experts and the drug manufacturer.Two independent reviewers screened the literature in two stages (title and abstract, full-text) using Covidence software. Two independent reviewers assessed the risk of bias on a 'per outcome' basis using the Cochrane 'Risk of bias; tool and rated the quality of evidence according to GRADE. Results of the single eligible trial were reported in a 'Summary of findings' table based on an intention-to-treat analysis.

MAIN RESULTS

Based on a single trial and moderate-quality evidence, alvimopan reduced the time to reach a composite endpoint of tolerance of solid food and documented bowel movements (hazard ratio (HR) 1.77, 95% confidence interval (CI) 1.41 to 2.23). This represents 165 more patients (109 more to 207 more) per 1000 meeting this endpoint within 10 days of surgery. Based on moderate-quality evidence, alvimopan reduced the time to hospital discharge (HR 1.67, 95% CI 1.38 to 2.01). This represents 138 more patients (82 more to 198 more) per 1000 being discharged within 10 days of surgery. Also based on moderate-quality evidence, alvimopan was associated with a reduced risk of major adverse events (risk ratio (RR) 0.28, 95% CI 0.18 to 0.44) representing 355 fewer patients (404 fewer to 276 fewer) with major adverse events per 1000. We downgraded this outcome for indirectness as it included adverse events that we did not consider major.In terms of secondary outcomes, alvimopan did not appear to alter the rate of readmission (RR 0.89, 95% CI 0.59 to 1.33), change the rate of any cardiovascular event (RR 0.54, 95% CI 0.27 to 1.05) or alter the mean narcotic pain medication use (mean difference 0, 95% CI 14.08 fewer to 14.08 more morphine equivalents). The quality of evidence was moderate for all three outcomes. Based on high-quality evidence, alvimopan reduced the rate of nasogastric tube replacement (RR 0.31, 95% CI 0.16 to 0.59). We did not find evidence for the drug's impact on rates of parenteral nutrition. All outcomes were short term and limited to a 30-day time horizon.Based on the existence of only one trial, we were unable to perform any subgroup or sensitivity analyses.

AUTHORS' CONCLUSIONS

In patients undergoing radical cystectomy and urinary diversion, the use of alvimopan administered as part of an enhanced recovery pathway for a limited duration (up to 15 doses for up to seven days) probably reduces the time to tolerance of solid food, time to hospital discharge and rates of major adverse events. Readmission rates, rates of cardiovascular events and narcotic pain requirements are probably similar. The need for reinsertion of nasogastric tubes is reduced. We found no evidence for the impact on rates of parenteral nutrition within 30 postoperative days.

A Double-Blinded Randomized Clinical Study on the Therapeutic Effect of Gastrografin in Prolonged Postoperative Ileus After Elective Colorectal Surgery

BACKGROUND

Postoperative ileus is a common problem with significant clinical and economic consequences. We hypothesized that Gastrografin may have therapeutic utility by accelerating the recovery of postoperative ileus after colorectal surgery. The aim of this trial was to study the impact of oral Gastrografin administration on postoperative prolonged ileus (PPI) after elective colorectal surgery.

METHODS

The main endpoint of this randomized, double-blinded, controlled trial was time of resolution of PPI. The secondary endpoints were overall hospital length of stay, time to start oral intake, time to first passage of flatus or stools, time of need of nasogastric tube, and need of parenteral nutrition. Included criteria were patients older than 18 years, operated for colonic neoplasia, inflammatory bowel disease, or diverticular disease. There were two treatments: Gastrografin administration and placebo. The sample size was calculated taking into account the average length of postoperative ileus after colorectal resection until tolerance to oral intake. Statistical analysis showed that 29 subjects in each group were needed.

RESULTS

Twenty-nine patients per group were randomized. Groups were comparable for age, gender, ASA Physical Status Classification System, stoma construction, and surgical technique. No statistical differences were observed in mean time to resolution between the two groups, 9.1 days (CI 95%, 6.51-11.68) in Gastrografin group versus 10.3 days (CI 6.96-10.29) in Placebo group (P = 0.878). Even if not statistically significant, time of resolution of PPI, overall length of stay, time of need of nasogastric tube, and time to tolerance of oral intake were shorter in the G group.

CONCLUSIONS

Gastrografin does not accelerate significantly the recovery of prolonged postoperative ileus after elective colorectal resection when compared with placebo. However, it seems to clinically improve all the analyzed variables.

Prucalopride: For functional constipation only?

Prucalopride is a new prokinetic agent, recently available in Europe for the treatment of functional constipation in adults in whom treatment with laxatives failed to provide adequate relief. However, due to its intrinsic properties (highly selective agonist activity and high affinity for 5-HT4 receptors, neuroprotection), this drug has shown the potential to be used in other pathologic conditions, in and outside of the gastrointestinal tract. We performed a systematic review of the evidence supporting these possible alternative uses of prucalopride. Further studies in this area are, however, mandatory.

Multiple Mesenteric Panniculitis as a Complication of Sjögren's Syndrome Leading to Ileus

Mesenteric panniculitis (MP) is a benign fibroinflammatory process characterized by the presence of fat necrosis, chronic inflammation and fibrosis in the mesentery. Although various causal factors, such as malignancy, chronic inflammatory conditions and autoimmune processes, have been identified, the precise etiology remains unknown. We herein report a rare case of MP accompanying Sjögren's syndrome in which a mass lesion and intestinal stenosis were observed simultaneously. This condition led to ileus, which was effectively treated using prednisolone.

[PROPHYLAXIS OF AN ACUTE ADHESIVE ILEUS RECURRENCE]

The results of treatment of 56 patients were studied, in whom for adhesive abdominal disease, complicated by an acute adhesive ileus (AAI), the adhesiolysis with intraabdominal introduction of antiadhesive measures, named Mezogel, Defensal were conducted, as well as in 42 patients, operated on in emergency for AAI, using a routine method. Application of videolaparoscopy gives a possibility to control the adhesive process in the early postoperative period, what is necessary for prophylaxis of the adhesive disease occurence. Application of the apparatus, we have elaborated, permitted to conduct a precisional viscerolysis due to good visualization of organs, pathologically changed and healthy tissues. Application of the procedures elaborated for prophylaxis of the AAI recurrence have promoted the reduction of risk for the AAI occurence down to 1.8%, and of disorders of the gut contents transit in terms up to 1 yr - to 3.6%.

Effect of Intraoperative Dexmedetomidine Infusion on Postoperative Bowel Movements in Patients Undergoing Laparoscopic Gastrectomy: A Prospective, Randomized, Placebo-Controlled Study

Sympathetic hyperactivation is one of the causes of postoperative ileus, which occurs frequently after abdominal surgery and adversely influences the patient's prognosis. We aimed to investigate whether dexmedetomidine (DEX) could attenuate postoperative ileus in patients undergoing laparoscopic gastrectomy. Ninety-two patients were randomized to the control (n = 46) or DEX group (n = 46). DEX was administered at a loading dose of 0.5 μg/kg for 10 minutes, followed by an infusion rate of 0.4 μg/kg/h from insufflation of the pneumoperitoneum to the end of surgery. The primary goal was to compare postoperative bowel movements by evaluating the time to first flatus. The balance of the autonomic nervous system, duration of postoperative hospital stay, and pain scores were assessed. The time to first flatus was shorter in the DEX group compared with the control group (67.2 ± 16.8 hours vs 79.9 ± 15.9 hours, P < 0.001). The low-frequency/high-frequency power ratio during pneumoperitoneum increased in the control group, compared with baseline values and the DEX group. The length of postoperative hospital stay was shorter in the DEX group compared with the control group (5.4 ± 0.7 days vs 5.8 ± 1.1 days, P = 0.04). Patients in the DEX group had lower pain scores and required fewer analgesics at 1 hour postoperatively. DEX facilitated bowel movements and reduced the length of hospital stay in patients undergoing laparoscopic gastrectomy. This may be attributed to the sympatholytic and opioid-sparing effects of DEX.

[Prophylaxis of purulent complications in mechanical ileus]

In experiment, while simulating an acute ileus, the possibility of antibacterial preparations for prophylaxis of purulent--septic complications was studied. There was established, that while progressing purulent intestinal inflammation its wall already in 12 h losses a capacity to cumulate penicillines and aminoglycosides. In a phlegmon-like changed intestine during 48 h cephalosporins and fluorochinolons are accumulated in bactericidal concentration, making a destruction of intestinal wall and occurrence of purulent peritonitis by 6-12 h slower.

[Experimental substantiation of possibility of sanation for purulent enteritis in mechanical acute ileus]

In experiment on the model of mechanical acute ileus (AI) in accordance to morphological and microbiological investigations data there was established, that in intestinal wall, situated above the obstacle place, purulent enteritis occurs, what may constitute the origin of purulent-septic complications after elimination of the Al cause. Application of antibacterial preparations permits to slow down the progression of destructive processes in the affected intestinal wall.

[Prognostication and prophylaxis of the adhesions recurrence postoperatively in patients suffering acute adhesive peritoneal disease complicated by ileus]

The results of treatment of 92 patients, suffering an acute ileus, were analyzed. After urgent operative interventions for an acute ileus the recurrence have occurred in 19.6% patients. To reduce the operative intervention traumaticity the preference was given to local viscerolysis conduction. For the adhesions occurrence prophylaxis a barrier medicines were used, what have promoted the reduction of contents of a connective tissue metabolites, excluding oxyprolin, concentration of which have exceeded such in a control, what have guaranteed the risk lowering for postoperative adhesions occurrence.

Nicotine gum chewing: a novel strategy to shorten duration of postoperative ileus via vagus nerve activation

Postoperative ileus (POI) is a transit cessation of bowel motility after surgery. Substantial evidences suggest that gum chewing accelerate the recovery of bowel motility after surgery. Perioperative nicotine administration reduces postoperative opioid use and prevents postoperative nausea and vomiting. Nicotine gum chewing combines stimulation of the cephalic-vagal reflex by gum chewing, and activation of the cholinergic anti-inflammatory pathway by nicotine administration. We therefore hypothesized that nicotine gum chewing reduces POI and improves patient outcomes such as shortening the length of hospitalization as well as saving medical costs. As nicotine gum is commercially available, inexpensive, and has been in use for many years without any severe side effects, it may have a wide clinical application in POI prevention.

[Optimization of surgical tactics in an acute adhesive ileus]

The results of treatment of 157 patients, suffering an acute adhesive ileus (AAI), were analyzed. Indications for laparoscopic and open adhesiolysis were substantiated. There was established, that laparoscopic adhesiolysis is effective in patients in adhesions process (AP) of I - II stages on the height of a seizure. Conduction of laparoscopic adhesiolysis after AAI elimination, using conservative methods in patients with AP I - III stages is effective and constitutes one of prophylactic methods for the adhesions disease recurrence and AAI.

The effects of iloprost on colonic anastomotic healing in rats under obstructive ileus conditions

BACKGROUND

The aim of this study was to investigate the effects of iloprost, on colonic anastomotic healing in rats, under obstructive ileus conditions.

MATERIALS AND METHODS

Eighty male Albino rats were randomized into four groups of 20 animals each. They underwent colonic resection followed by an inverted anastomosis. The rats of group 1 (control) and group 2 (ileus) received 3 mL of saline 0.9% intraperitoneally and those of group 3 (iloprost), and group 4 (ileus + iloprost) iloprost (2 μg/kg of body weight), immediately postoperatively and daily until the day of sacrifice. Each group was further divided into two equal subgroups, depending on the day of sacrifice. The animals of subgroup "a" were sacrificed on the fourth postoperative day, whereas those of "b" on the eighth day. Macroscopic and histologic assessment was performed, whereas anastomotic bursting pressures and the tissue concentrations in hydroxyproline and collagenase I were evaluated.

RESULTS

Means of bursting pressure, neoangiogenesis, fibroblast activity, and hydroxyproline concentration were significantly increased in group 4 compared with group 2. In addition, on the fourth postoperative day, the inflammatory cell infiltration and the collagenase I concentration were significantly decreased in group 4 compared with group 2. Moreover, on the eighth postoperative day, collagen deposition was significantly increased in group 4 compared with group 2.

CONCLUSIONS

Iloprost after intraperitoneal administration reverses the negative effect of obstructive ileus. It promotes not only the angiogenic activity but also collagen formation, resulting in increased bursting pressures on the fourth and eighth postoperative days.

Daikenchuto stimulates colonic motility after laparoscopic-assisted colectomy

BACKGROUND/AIMS

Paralytic ileus after laparoscopic-assisted surgery often occurs. We investigated whether daikenchuto (DKT), a traditional Japanese herbal medicine, improves intestinal motility in patients undergoing laparoscopic-assisted colectomy for colon cancer.

METHODOLOGY

Fifty-four patients who underwent colectomy at Iwate Medical University Hospital between October 2010 and March 2012 were randomized to either the DKT group (7.5 g/day, p.o.) or the control group (lactobacillus preparation, 3g/day, p.o.). Primary endpoints included time to first flatus, bowel movement, and tolerance of diet after extubation. Secondary endpoints were WBC count, C-reactive protein (CRP) level, length of hospital stay, and postoperative ileus. Colonic transit time was measured using radiopaque markers and abdominal radiographs.

RESULTS

Fifty-one patients (DKT, 26 vs. control, 25) were included in the per-protocol analysis. The DKT group had significantly faster time until first flatus (67.5 +/- 13.6h vs. 77.9 +/- 11.8h, P < 0.01) and bowel movement (82.9 +/- 17.8h vs. 99.5 +/- 18.9h, P < 0.01) and colonic transit time (91.9 +/- 19.8h vs. 115.2 +/- 12.8 h, P < 0.05). There were no significant intergroup differences in secondary endpoints and adverse events.

CONCLUSIONS

DKT accelerates colonic motility in patients undergoing laparoscopic-assisted colectomy for colon cancer.

Word of caution before implementing ketotifen for gastrointestinal transit improvement

The therapeutic potential of long-term ketotifen in irritable bowel syndrome and postoperative ileus is currently under investigation. Ambiguous results of prolonged postoperative ketotifen use on gastrointestinal passage have been found. The current data point at a hampered gastrointestinal transit after prolonged postoperative ketotifen use in a rodent ileus induction model. Therefore, caution should be taken when administering ketotifen in the perioperative phase.

Effects of dried Citrus unshiu peels on gastrointestinal motility in rodents

Aqueous extracts of the dried mature (ANP-W) and immature Citrus unshiu peels (CUP-W) have been used as a traditional folk medicine for the treatment of gastrointestinal (GI) motility disorders in Korea. In the present study, neither ANP-W nor CUP-W exhibited significant toxicity even at an oral dose of 5 g/kg to mice. The effects of ANP-W and CUP-W on GI motor function were investigated by measuring the intestinal transit rate (ITR) of Evans blue in normal mice and rats with experimental GI motility dysfunctions (GMDs). In normal mice, the ITR was significantly increased by ANP-W (0.1-1 g/kg) in a dose dependent manner, whereas CUP-W elicited no significant change. GMD was induced by appropriate surgery or an intraperitoneal injection of acetic acid to the rats. The ITR in the GMD rats was significantly retarded compared to that in normal rats. However, the retardation was significantly inhibited by ANP-W (0.1-1 g/kg) in a dose dependent manner. The above results suggest that ANP-W has the potential for development as a prokinetic agent that may prevent or alleviate GMD in human patients.

[Efficacy of application of thiopoietines in complex of treatment of an acute adhesive ileus in patients with hepatic function disorder]

The peculiarities of an acute adhesive ileus (AAI) course in patients, suffering hepatic function disorder (HFD), were studied up, the additions to the conservative treatment scheme were proposed. There was established, that while HFD presence in the patients the trustworthy enhanced recurrence rate of adhesive disease is observed after operations, performed for AAM, The adhesive disease recurrence rate do not depend on the surgical access kind. Application of preparations, related to thiopoietins group and hepatoprotectors, while AAI treatment conduction, have promoted reduction of the peritoneal adhesive disease recurrence rate in terms of the three years postoperative follow-up.

Alvimopan for acceleration of GI recovery after bowel resection

Nurses play a critical role in the management of postoperative ileus during the perioperative phase of recovery. Alvimopan is an oral, peripherally acting, mu-opioid receptor antagonist that accelerates time to gastrointestinal recovery (resolution of postoperative ileus), representing a potential advance in management of these patients.

A pilot study of the effect of pantothenic acid in the treatment of post-operative ileus: results from an orthopedic surgical department

OBJECTIVES

Post-operative ileus can also occur in other types of surgery not strictly related to abdomen. The objective of this study was to investigate the efficacy of pantothenic acid administration to stimulate intestinal peristalsis in case of post-operative ileus and estimate the most effective dose. This vitamin can be used for the treatment of chronic atonic intestine or for chronic constipation, but therapeutic indications are not precise in these conditions.

PATIENTS AND METHODS

This pilot study has used patients divided in groups treated in post-operative period with physiological solution for patients in control group (Placebo) and Dexpantenolo, which is a derivative in alcohol of pantothenic acid, for all the actively treated patients. The treatments were administered intravenously during the second and third post-operative day, according to the treatment schedule.

RESULTS

60 patients were recruited and they were allocated to five treatment groups or one control group. For males, the median time of the first bowel evacuation was 90 hours while for females the median time was 84 hours (p=0.891). For patients who received a spinal anesthetic, the median time was 72 hours, while for those who received a peridural anesthetic the median time was 96 hours (p=0.571). Between six treatment groups, instead, there is a significant difference between the median times from the operation to the first bowel evacuation (p<0.001). Linear regression model obtained using as outcome evacuation hours after surgery show that only variable which significantly affects time between operation and the first bowel evacuation is treatment dose (Beta = -0.868, p<0.001).

DISCUSSION

This study would seem to indicate that pantothenic acid is effective for treatment of post-operative intestinal ileus; there is a dose response relationship between pantothenic acid and the decreasing time from surgical operation to first bowel evacuation. However, this study is preliminary; further studies are necessary, preferably randomized and with a larger number of patients.

Ghrelin as a target for gastrointestinal motility disorders

The therapeutic potential of ghrelin and synthetic ghrelin receptor (GRLN-R) agonists for the treatment of gastrointestinal (GI) motility disorders is based on their ability to stimulate coordinated patterns of propulsive GI motility. This review focuses on the latest findings that support the therapeutic potential of GRLN-R agonists for the treatment of GI motility disorders. The review highlights the preclinical and clinical prokinetic effects of ghrelin and a series of novel ghrelin mimetics to exert prokinetic effects on the GI tract. We build upon a series of excellent reviews to critically discuss the evidence that supports the potential of GRLN-R agonists to normalize GI motility in patients with GI hypomotility disorders such as gastroparesis, post-operative ileus (POI), idiopathic chronic constipation and functional bowel disorders.

Can the intestinal dysmotility of critical illness be differentiated from postoperative ileus?

Gastrointestinal dysmotility is commonly noted in the intensive care unit and postoperative settings. Characterized by delayed passage of stool and flatus, nausea, vomiting, and abdominal distention, the condition is associated with nutritional deficiencies, risk of aspiration, and considerable allocation of health care resources. Knowledge of gastrointestinal function in health and illness continues to expand. While the factors that precipitate ileus differ between postoperative and critically ill patients, the two clinical scenarios seem to have similar mechanisms and share many of the same pathophysiologic patterns. By reviewing and comparing the literature on the respective mechanisms and contributing factors generated in these separate clinical settings, a common more comprehensive management strategy may be derived with the potential for newer innovative therapeutic options.

[Ileus as a manifestation of intestinal tuberculosis]

BACKGROUND

'Intestinal tuberculosis' is sometimes difficult to diagnose. The symptoms are non-specific and there is an extensive differential diagnosis.

CASE DESCRIPTION

A 27-year-old man from Pakistan presented at the emergency department with a history of constipation, weight loss and abdominal pain. An abdominal CT scan revealed dilated small bowel loops, lymphadenopathy and a thickened intestinal wall of the terminal ileum. Cultures of a cervical lymph node biopsy tested positive for Mycobacterium tuberculosis: intestinal tuberculosis. The man eventually recovered after treatment with tuberculostatics.

CONCLUSION

The most sensitive methods for establishing the diagnosis 'intestinal tuberculosis' are an abdominal CT scan and a colonoscopy with ileal and colonic biopsies; establishing the diagnosis can be challenging as a result of non-specific test results.

Molecular Medicine - CHI's 17th International Tri-Conference: Mastering Medicinal Chemistry - CHI's Seventh Annual Conference

CHI's 17th International Tri-Conference on Molecular Medicine, held in San Francisco, included topics covering the drug discovery process, with an emphasis on lead optimization. This conference report highlights selected presentations on the development of several launched and investigational drugs, including Plerixafor, Trox-1 (CombinatoRX Inc), lorcaserin (Arena Pharmaceuticals Inc), vorapaxar (Merck & Co Inc) and ulimorelin (Tranzyme Pharma Inc).

[Systemic prokinetic treatment of postoperative ileus following abdominal surgery. Assessment of a Cochrane review]

Based on the evidence presented in the Cochrane review "Systemic prokinetic pharmacologic treatment for postoperative adynamic ileus following abdominal surgery in adults", routine administration of systemic prokinetics for the prevention of postoperative ileus is not recommendable. The potential of selective opioid antagonists and intravenous lidocaine should be further investigated, particularly in conjunction with laparoscopic surgery, epidural pain management and fast-track surgery.

[A case of successful treatment using octreotide acetate for occlusive ileus in terminal stage cancer]

We report a 35-year-old female bearing ovarian cancer who was suffering from intestinal obstruction due to multiple recurrences. The treatment of 300 microg/day of octreotide acetate was started. The symptom of obstruction, such as vomiting and nausea, caused by intestinal obstruction was suddenly controlled and the quality of life was improved. Octreotide acetate can be applied for the management of intestinal obstruction caused by metastases at the terminal stage of cancer.

Gastric and small bowel ileus after severe burn in rats: the effect of cyclooxygenase-2 inhibitors

Gastrointestinal (GI) ileus is a common complication after severe burns. Selective cyclooxygenase-2 inhibitors (COX-2i) improved post-operative ileus, but its effect on burn-induced GI dysmotility is unknown. Our aim was to test whether a COX-2i improves gastric emptying (GE) and small bowel transit (SBT) after burn. Experiment on GE: rats were anesthetized and randomized into sham/scald burn, treated/untreated with COX-2i. Six hours after burn, rats received a phenol red meal and were sacrificed 30 min later. Gastric emptying was determined based on the percentage of phenol red recovered in harvested stomachs. Experiment on SBT: rats received a duodenostomy and were scald/sham burned 5 days later. Six hours after burn, rats received a phenol red meal through the duodenostomy catheter and were sacrificed 100 min later. Geometric center (GC) was calculated for SBT. GE was decreased significantly in burned vs. sham animals (p<0.001). SBT was significantly impaired in burned vs. sham animals (p<0.001). The COX-2i improved GE in the burn rats but not GE in the control rats or SBT in the burn rats. COX-2i improves burn-induced delayed GE, suggesting the mediation of the latter via the prostaglandin pathway.

Pilot postoperative ileus study of escin in cancer patients after colorectal surgery

BACKGROUND

Postoperative ileus, a common complication in patients after abdominal surgery, brings no benefit to the recovery of postoperative patients, and treatment targeted at restoring gastrointestinal motility may shorten the hospital stay. Studies have shown that escin accelerates gastrointestinal transit in mice and improves gastrointestinal motility in patients after abdominal surgery. A pilot study of escin's effect on the recovery of gastrointestinal motility was conducted in colorectal cancer patients in anticipation of a multiple-center randomized controlled trial.

METHODS

A total of 72 postoperative colorectal cancer patients were randomly assigned to four parallel groups on the basis of sealed envelopes-escin 5 mg group (E5 mg), escin 15 mg group (E15 mg), escin 25 mg group (E25 mg), and placebo group-with 18 patients in each group. Escin or placebo was diluted in 500 ml 5% dextrose injection, which was given once daily through the subclavian vein. The first injection took place 6 h after completion of the surgery. The treatment continued for 7 days or stopped at the time of the patient's first bowel movement. Time to recovery of passage of gas (TRPG), time to recovery of gastrointestinal sounds (TRGS), and time to recovery of bowel movements (TRBM) were recorded to evaluate the efficacy of escin.

RESULTS

The TRPGs of the three escin treatment groups were 76.78 + 28.81 h (E5 mg), 72.06 + 14.65 h (E15 mg), and 65.50 + 26.70 h (E25 mg), respectively, with differences of 6.03 +/- 7.64 h (p = 0.436; E5 mg), 10.75 +/- 4.92 h (p = 0.036; E15 mg), and 17.31 +/- 7.20 h (p = 0.022; E25 mg) compared with the placebo group. The TRGSs of the three escin treatment groups were 45.28 +/- 26.15 h (E5 mg), 41.22 +/- 16.98 h (E15 mg), and 40.33 +/- 14.09 h (E25 mg), respectively, with differences of 4.33 +/- 7.12 h (p = 0.547; E5 mg), 8.39 +/- 5.36 h (p = 0.127; E15 mg), and 9.28 +/- 4.87 h (p = 0.065; E25 mg) compared with the placebo group. The TRBMs of the three escin treatment groups were 89.25 +/- 23.77 h (E5 mg), 84.83 +/- 27.91 h (E15 mg), and 84.44 +/- 19.74 h (E25 mg), respectively, with differences of 19.03 +/- 10.13 h (p = 0.069; E5 mg), 23.44 +/- 10.70 h (p = 0.035; E15 mg), and 23.83 +/- 9.63 h (p = 0.019; E25 mg) compared with the placebo group.

CONCLUSION

The results of this pilot Postoperative Ileus Study of Escin (PISE) showed that escin can shorten the time to recovery of gastrointestinal motility in cancer patients after colorectal surgery.

Novel opioid antagonists for opioid-induced bowel dysfunction and postoperative ileus

Peripherally acting mu-opioid receptor antagonists methylnaltrexone and alvimopan are a new class of drugs designed to reverse opioid-induced side-effects on the gastrointestinal system without compromising pain relief. This article gives an overview of the pharmacology, the efficacy, and adverse effects of these drugs. Both compounds seem to be generally well tolerated and effective for the treatment of opioid-related bowel dysfunction and postoperative ileus. Methylnaltrexone recently received approval by the US Food and Drug Administration (FDA) and the European Medicines Agency for treatment of opioid-related bowel dysfunction in patients with advanced illness. Alvimopan was recently approved by the FDA for treatment of postoperative ileus, but the use of the drug is restricted to inpatients because it has been associated with an increased rate of myocardial infarction. Further research should assess the effectiveness and safety of these drugs in clinical practice.

Pharmacological management of postoperative ileus

The duration of postoperative ileus following abdominal surgery is quite variable, and prolonged postoperative ileus is an iatrogenic phenomenon with important influence on patient morbidity, hospital costs and length of stay in hospital. Adequate treatment for prolonged postoperative ileus is important to improve patient morbidity and clinical efficiency. Both clinical and pharmacological management strategies have improved rapidly over the last decade, and appropriate and timely management using multimodal techniques should be used for optimal care. In this review, we define postoperative ileus, describe the pathogenesis and briefly discuss clinical management before detailing potential pharmacologic management options.

Contractile effects of 5-hydroxytryptamine (5-HT) in the equine jejunum circular muscle: functional and immunohistochemical identification of a 5-HT1A-like receptor

REASONS FOR PERFORMING STUDY

Prokinetic drugs used to treat gastrointestinal ileus in man have equivocal results in horses. In man, prokinetic drugs have 5-hydroxytryptamine4(5-HT4) receptors as their target, but little is known about the 5-HT-receptor subtypes in the equine small intestine.

OBJECTIVE

Functional and immunohistochemical identification of the serotonin receptor subtype(s) responsible for the 5-HT induced contractile response in the equine circular jejunum.

METHODS

Isometric organ-bath recordings were carried out to assess spontaneous and drug-evoked contractile activity of equine circular jejunum. Histological investigations by immunofluorescence analyses were performed to check for presence and localisation of this functionally identified 5-HT receptor subtype.

RESULTS

Tonic contractions were induced by 5-HT in horse jejunal circular muscle. Tetrodotoxin, atropine and NG-nitro L-arginine did not modify this response. A set of 5-HT receptor subtype selective antagonists excluded interaction with 5-HT1B, 1D, 2A, 3, 4 and 7 receptors. The selective 5-HT1A receptor antagonists WAY 100635 and NAN 190 caused a clear rightward shift of the concentration-response curve to 5-HT. The contractile effect of 5-CT, that can interact with 5-HT1A, 1B, 1D, 5 and 7 receptors was also antagonised by WAY 100635, identifying the targeted 5-HT receptor as a 5-HT1A-like receptor. Immunohistology performed with rabbit polyclonal anti-5-HT1A receptor antibodies confirmed the presence of muscular 5-HT1A receptors in the muscularis mucosae, and both longitudinal and circular smooth muscle layers of the equine jejunum.

CONCLUSIONS

Contractile responses in equine jejunal circular smooth muscle induced by 5-HT involves 5-HT1A-like receptors.

Distribution of the neurokinin-1 receptor in equine intestinal smooth muscle

REASON FOR PERFORMING STUDY

Tachykinins have profound effects on equine intestinal motility, but the distribution of the neurokinin receptors (NKRs) through which they act is unknown. This study reports the distribution of one of these receptors, the neurokinin-1 receptor (NK1R), in smooth muscle throughout the equine intestinal tract.

OBJECTIVES

To quantify the distribution of the NK1R, based upon mRNA expression, in smooth muscle of different regions of the equine intestinal tract.

METHODS

Nine regions of the intestinal tract were sampled in 5 mature horses. Total RNA was isolated from smooth muscle and reverse transcribed; NK1R mRNA was then quantified using real-time PCR.

RESULTS

NK1R mRNA was found at all levels of the sampled intestinal tract. The smooth muscle of the proximal small intestine and the ventral colon exhibited the highest level of NK1R mRNA expression in the equine intestinal tract.

CONCLUSIONS

Tachykinins probably affect intestinal contractility and propulsion in the proximal small intestine and in the ventral colon.

Methylnaltrexone, a new peripheral mu-receptor antagonist for the prevention and treatment of opioid-induced extracerebral side effects

Progenics Pharmaceuticals Inc and Wyeth Pharmaceuticals are developing methylnaltrexone, a micro-receptor opioid antagonist derived from naltrexone by the addition of a methyl group. The intravenous formulation of methylnaltrexone is currently in phase III clinical trials for the potential treatment of postoperative ileus.