Prolonged Postoperative Ileus Research Articles

Prevention and Management of Postoperative Ileus: A Review of Current Practice.

Postoperative ileus (POI) has long been a challenging clinical problem for both patients and healthcare physicians alike. Although a standardized definition does not exist, it generally includes symptoms of intolerance to diet, lack of passing stool, abdominal distension, or flatus. Not only does prolonged POI increase patient discomfort and morbidity, but it is possibly the single most important factor that results in prolongation of the length of hospital stay with a significant deleterious effect on healthcare costs in surgical patients. Determining the exact pathogenesis of POI is difficult to achieve; however, it can be conceptually divided into patient-related and operative factors, which can further be broadly classified as neurogenic, inflammatory, hormonal, and pharmacological mechanisms.Different strategies have been introduced aimed at improving the quality of perioperative care by reducing perioperative morbidity and length of stay, which include Enhanced Recovery After Surgery (ERAS) protocols, minimally invasive surgical approaches, and the use of specific pharmaceutical therapies. Recent studies have shown that the ERAS pathway and laparoscopic approach are generally effective in reducing patient morbidity with early return of gut function. Out of many studies on pharmacological agents over the recent years, alvimopan has shown the most promising results. However, due to its potential complications and cost, its clinical use is limited. Therefore, this article aimed to review the pathophysiology of POI and explore recent advances in treatment modalities and prevention of postoperative ileus.

Postoperative ileus: A pharmacological perspective.

Postoperative ileus (POI) is a frequent complication after abdominal surgery. The consequences of postoperative ileus can be potentially serious such as bronchial inhalation or acute functional renal failure. Numerous advances in peri-operative management, particularly early rehabilitation, have made it possible to decrease postoperative ileus. Despite this, the rate of prolonged postoperative ileus remains high and can be as high as 25% of patients in colorectal surgery. From a pathophysiological point of view, postoperative ileus has two phases, an early neurological phase and a later inflammatory phase, to which we could add a 'pharmacological' phase during which analgesic drugs, particularly opiates, play a central role. The aim of this review article is to describe the phases of the pathophysiology of postoperative ileus, to analyse the pharmacological treatments currently available through published clinical trials and finally to discuss the different research areas for potential pharmacological targets.

Activation of p38 mitogen-activated protein kinase pathway by lipopolysaccharide aggravates postoperative ileus in colorectal cancer patients.

Patients undergoing abdominal surgery can develop postoperative ileus (POI). Inflammation of the intestinal muscularis following intestinal manipulation may be caused by displaced bacteria or lipopolysaccharide (LPS). The aim of this study was to investigate the relationship between gut microbiota, LPS, and POI in colorectal cancer (CRC) patients and explore underlying mechanisms of LPS-triggered POI. Sixty CRC patients undergoing colorectal resection were included. Bacterial communities from fecal samples were characterized by 16S rRNA gene sequencing, and fecal LPS levels were determined by Limulus amebocyte lysate assay. Mice were used to mechanistically investigate the causal relationship between microbiota, LPS, and POI. We discovered that CRC patients who developed prolonged POI (PPOI) had a unique pro-inflammatory gut microbial composition during the perioperative period. The highest proportions of Gram-negative bacteria at the genus level were Escherichia-Shigella and Bacteroides; the abundance of Escherichia-Shigella was higher throughout the perioperative period. Fecal LPS levels were significantly higher in patients with PPOI. In mice treated with an antibiotic cocktail, intestinal muscularis inflammation and intestinal dysfunction were significantly improved. Inflammation and dysfunction were significantly reduced in mice treated with polymyxin B, but were worsened by treatment with LPS. Moreover, LPS upregulated p38 phosphorylation in mice, and treatment with an inhibitor of p38 (SB203580) significantly alleviated intestinal inflammation and dysmotility. Lipopolysaccharide increases intestinal muscularis inflammation via activation of p38 signaling, which aggravates POI. Removing bacterial sources of LPS during the perioperative period is promising for the prophylactic treatment of PPOI.

P129 THORACIC VS. ABDOMINAL APPROACHES FOR DIAPHRAGMATIC HERNIA REPAIR: A NATIONWIDE STUDY OF CLINICAL OUTCOMES

Abstract Aim “To compare the outcomes of different surgical approaches for diaphragmatic hernia (DH) repair.” Material and Methods “Adult patients with a principal admitting diagnosis of uncomplicated DH registered in the National Inpatient Sample in the period 2010-2015 were included. Patients with obstruction, gangrene, or congenital hernias were excluded. The primary outcome was in-hospital mortality. Secondary outcomes were the incidence of complications, length of stay, and hospital charges. A multivariate logistic regression model adjusted by age, sex, elective admission, comorbidities, and hospital characteristics was used to analyze the impact of the surgical approach on the evaluated outcomes.” Results “A total of 14910 patients with DH were included (median age 65 years, 74% women). Abdominal approaches were the most commonly performed (78.9% laparoscopy and 13.6% open). Patients that underwent open abdominal and thoracic repairs had a higher risk of complications (sepsis, pneumonia, surgical site infection, prolonged postoperative ileus, and acute myocardial infarction), longer hospital stay, higher total hospital costs, and a significantly higher risk of mortality (OR 2.62. 95% CI 1.59-4.30 and OR 4.60; 95% CI 2.37-8.91, respectively) compared to patients that underwent laparoscopic abdominal repair. Individuals whose DH repair was performed through thoracoscopy had a similar mortality risk to those who underwent laparoscopic abdominal repair (OR 0.87; 95% CI 0.11-6.43).” Conclusions “Nowadays, laparoscopy has become the most used approach for DH repair. In the present cohort, it was associated with better outcomes in terms of complications, length of hospital stay, and mortality, as well as lower health costs. Additional studies assessing hernia characteristics are required to validate this result.”

Prolonged postoperative ileus following right- versus left-sided colectomy: A systematic review and meta-analysis.

Prolonged postoperative ileus (PPOI) is a common complication following colonic surgery, and is associated with longer hospital stay, greater risk of complications and substantial cost for patients and hospitals. Some reports have recently suggested that gastrointestinal (GI) recovery varies based on the side of resection (i.e., right-sided vs. left-sided colectomy). This systematic review and meta-analysis aimed to compare GI recovery by resection side. The MEDLINE, Embase, Cochrane Library and CENTRAL databases were systematically searched for articles reporting GI recovery outcomes in adults undergoing elective right- versus left-sided colectomy (excluding with ileostomy) of any surgical approach. The primary outcome was PPOI, and secondary outcomes included time to first passage of flatus, stool and tolerance of solid diet, and postoperative complications. Subgroup analyses of laparoscopic procedures and cohorts without inflammatory bowel disease and sensitivity analysis of adjusted multivariate results were also performed. Nine studies were identified, of which seven were included in the meta-analysis, comprising 29068 colectomies (14581 right-sided; 14487left-sided). PPOI was heterogeneously defined and was significantly more likely following right-sided compared to left-sided colectomy regardless of the surgical approach (OR 1.78, 95% CI 1.32-2.39; P<0.01; I2 =51%), as well as on subgroup analyses and adjusted multivariate meta-analysis. Secondary outcomes were reported in only a few small studies; hence meta-analysis did not produce reliable results. Based on heterogeneous definitions, consistently higher rates of PPOI were observed following right- versus left-sided colectomy. These differences are currently unexplained and highlight the need for further research into the pathophysiology of ileus.

Peri-operative Inflammatory Marker as a Predictive Factor for Prolonged Post-operative Ileus After Gastrectomy for Gastric Cancer.

Background/AimsAlthough prolonged post-operative ileus (PPOI) is an important factor for the prolonged length of post-operative hospital stay, there is still a lack of effective predictive and therapeutic methods for PPOI. Previous studies reported that increased inflammatory markers, such as C-reactive protein (CRP) level and neutrophil to lymphocyte ratio (NLR), are associated with malignancies. The aim of our study is to elucidate the association between peri-operative inflammatory markers and PPOI after gastrectomy for gastric cancer.MethodsWe enrolled patients who received gastrectomy for gastric cancer from June 2013 to January 2016 at a single tertiary referral center in Seoul, Korea. We evaluated peri-operative inflammatory markers, including CRP level, NLR, and platelet to lymphocyte ratio (PLR) of enrolled patients. We compared these data between control group and PPOI group.ResultsA total of 390 subjects were enrolled in this study, and 132 patients (33.8%) showed PPOI. In univariate analysis, preoperative CRP level and NLR, post-operative day (POD) 1 CRP level, NLR, and PLR, and POD3 CRP level, NLR, and PLR were significantly associated with PPOI. In multivariate analysis, preoperative NLR (P = 0.014), POD1 NLR (P = 0.019), POD3 CRP (P = 0.004), and POD3 NLR (P = 0.008) were independent risk factors for PPOI.ConclusionsPeri-operative inflammatory markers, such as CRP level and NLR, are useful predictive factors for PPOI who received gastrectomy for gastric cancer. Moreover, prophylactic antibiotics and anti-inflammatory drugs can be preventive and therapeutic agents for PPOI.

Association of Abdominal Incision Length With Gastrointestinal Function Recovery Post-operatively: A Multicenter Registry System-Based Retrospective Cohort Study.

Objective: To evaluate the influence of the abdominal incision length on the gastrointestinal function recovery post-operatively.Background: Gut motility recovers more quickly after the minimally invasive laparoscopic surgery compared than after the traditional open surgery; however, whether the minimal abdominal incision contributes to the faster gut motility recovery is controversial and lacks solid clinical evidence.Methods: A registry-based secondary cohort analysis was conducted to evaluate the association between the abdominal incision length and gut motility recovery post-operatively based on a multicenter, prospective, and observational study of the prolonged post-operative ileus (PPOI) incidence and the risk factors in the patients with the major abdominal surgery. The incision length, in the centimeters, was the exposure. The primary outcome measures were the PPOI incidence and its association with the incision length. The secondary outcome included the days to the first passage of flatus and the days to the first passage of stool.Results: Overall, 1,840 patients, including 287 (15.7%) patients with the PPOI, were recruited. The PPOI incidence was 17.6% and 13.3% in the long-incision (>18 cm) and short-incision patients ( ≤ 18 cm), respectively. The incidence of the PPOI increased by 1.1% (1.0–1.1) by each centimeter increment of the incision length after adjusting for the confounding factors. In comparison to the short-incision patients, the long-incision patients had prolonged passage of stool (4.46 vs. 4.95 days, p < 0.001). Each centimeter increment of the incision length contributed to a 2% increased risk of delay in the first bowel movement [hazard ratio (HR) 0.980 (0.967, 0.994)].Conclusion: A long abdominal incision length independently contributed to the prolonged gut function recovery post-operatively mainly by delaying the time to the first bowel movement, but not influencing the time to first passage of flatus.

Modern Lower Extremity Bypass Outcomes by Anesthesia Type in the Veteran Population

Lower extremity bypass (LEB) revascularization can be performed under general (GA) or neuraxial anesthesia (NA). Studies show that the use of NA may decrease morbidity, 30-day mortality, and hospital length-of-stay (LOS). The goal of our analysis is to examine the differences in postsurgical outcomes following LEB between patients who undergo GA compared to NA in the Veteran Affairs Surgical Quality Improvement Program (VASQIP) database. After IRB approval, the VASQIP database was assessed for patients who underwent LEB between 1998-2018. Only infrainguinal bypass procedures and anesthesia type classified as "general," "epidural," or "spinal" were included. The neuraxial cohort includes both spinal and epidural anesthesia patients. The Risk Analysis Index (RAI), a validated measure of frailty, was additionally calculated for each patient. Chi squared, paired t-test, and binary logistic regression were used to compare the cohorts. During this period, 22,960 veterans underwent LEB recorded in VASQIP. Compared to those who underwent surgery under GA, patients with procedures performed using NA were older (66.4 ± 9.6 years vs. 65.3 ± 9 years respectively; P <0.001) and more frail (average RAI score 25.7 ± 7.0 vs. 24.9 ± 6.7; P < 0.001). Operative time was shorter in the NA group (4.1 ± 1.7 hrs vs. 4.7 ± 3.0 hrs; P < 0.001) and fewer cases were emergent (1.55% vs. 4.13%; P <0.001). Patients in the GA group had higher rates of postoperative prolonged ileus (0.31% vs. 0.00%; P=0.03), pneumonia (1.60% vs. 1.06%; P=0.025), deep wound infection (2.67% vs. 2.61%; P=0.01), sepsis (1.68% vs. 0.79%; P < 0.001), reintubation (1.80% vs. 1.30%) (P=0.04),and number of packed red blood cell (pRBC) transfused intraoperatively (0.39 ± 1.21 units vs. 0.22 ± 0.79 units; P <0.001). There was no significant difference in rate of graft failure, return to the OR, myocardial infarction, death, or LOS. In regression analysis, those undergoing NA were less likely to require pRBC transfusion intraoperatively (OR: 0.43; 95% CI: 0.31-0.61; P < 0.001), however no other outcomes reached statistical significance. Although younger and less frail, veteran patients undergoing GA for lower extremity revascularization had higher rates of postoperative ileus, pneumonia, deep wound infection, sepsis, and need for transfusion as compared to those undergoing NA. There was no significant difference in the rate of other major complications, myocardial infarction, death or LOS. After adjustment, only intraoperative transfusion remained statistically significant, likely reflecting longer and more complex cases for those that undergo general anesthesia rather than the effect of anesthetic choice itself.

Should minimally invasive approaches in rectal surgery be regarded as a key element of modern enhanced recovery perioperative care?

Introduction The aim of study was to assess the impact of an enhanced recovery after surgery (ERAS) protocol and minimally invasive approaches on short-term outcomes in rectal surgery. Patients and methods A consecutive series of patients that underwent open or minimally invasive rectal resections in a single institution between January 2015 and April 2020 were included in the study. An ERAS program was introduced in April 2016. The study cohort was divided into three groups: open surgery without ERAS, open surgery with ERAS, and minimally invasive surgery with ERAS. Outcome measures compared were recovery parameters, surgical stress parameters, 30-day morbidity and mortality, oncological radicality and length of hospital stay. Results A total of 202 patients were included: 43 in the open non-ERAS group, 92 in the open ERAS group and 67 in the minimally invasive ERAS group. All recovery parameters apart from postoperative nausea and vomiting were significantly improved in both ERAS groups. Surgical stress parameters, prolonged postoperative ileus, and hospital stay were significantly reduced in the minimally invasive ERAS group. The overall 30-day morbidity and mortality and oncological radicality did not significantly differ among the three groups. Conclusions Minimally invasive approaches and enhanced recovery care in rectal surgery improve short-term outcomes. Their combination leads to an improvement in recovery parameters and a reduction of prolonged postoperative ileus and hospital stay.

Risk factors for upper and lower type prolonged postoperative ileus following surgery for Crohn\u2019s disease

PurposeProlonged postoperative ileus (PPOI) is common after bowel resections, especially in Crohn’s disease (CD). The pathophysiology of PPOI is not fully understood. PPOI could affect only the upper or lower gastrointestinal (GI) tract. The aim of this study was to assess risk factors for diverse types of PPOI, particularly to differentiate PPOI of upper and lower GI tract.MethodsA retrospective analysis of 163 patients with CD undergoing ileocecal resection from 2015 to 2020 in a single center was performed. PPOI of the upper GI tract was predefined as the presence of vomiting or use of nasogastric tube longer than the third postoperative day. Lower PPOI was predefined as the absence of defecation for more than three days. Independent risk factors were identified by multivariable logistic regression analysis.ResultsOverall incidence of PPOI was 42.7%. PPOI of the upper GI tract was observed in 30.7% and lower PPOI in 20.9% of patients. Independent risk factors for upper PPOI included older age, surgery by a resident surgeon, hand-sewn anastomosis, prolonged opioid analgesia, and reoperation, while for lower PPOI included BMI ≤ 25 kg/m2, preoperative anemia, and absence of ileostomy.ConclusionThis study identified different risk factors for upper and lower PPOI after ileocecal resection in patients with CD. A differentiated upper/lower type approach should be considered in future research and clinical practice. High-risk patients for each type of PPOI should be closely monitored, and modifiable risk factors, such as preoperative anemia and opioids, should be avoided if possible.

Impact of STIMUlant and osmotic LAXatives (STIMULAX trial) on gastrointestinal recovery after colorectal surgery: randomized clinical trial.

Recovery of gastrointestinal (GI) function is often delayed after colorectal surgery. Enhanced recovery protocols (ERPs) recommend routine laxative use, but evidence of benefit is unclear. This study aimed to investigate whether the addition of multimodal laxatives to an ERP improves return of GI function in patients undergoing colorectal surgery. This was a single-centre, parallel, open-label RCT. All adult patients undergoing elective colorectal resection or having stoma formation or reversal at the Royal Adelaide Hospital between August 2018 and May 2020 were recruited into the study. The STIMULAX group received oral Coloxyl® with senna and macrogol, with a sodium phosphate enema in addition for right-sided operations. The control group received standard ERP postoperative care. The primary outcome was GI-2, a validated composite measure defined as the interval from surgery until first passage of stool and tolerance of solid intake for 24 h in the absence of vomiting. Secondary outcomes were the incidence of prolonged postoperative ileus (POI), duration of hospital stay, and postoperative complications. The analysis was performed on an intention-to-treat basis. Of a total of 170 participants, 85 were randomized to each group. Median GI-2 was 1 day shorter in the STIMULAX compared with the control group (median 2 (i.q.r. 1.5-4) versus 3 (2-5.5) days; 95 per cent c.i. -1 to 0 days; P = 0.029). The incidence of prolonged POI was lower in the STIMULAX group (22 versus 38 per cent; relative risk reduction 42 per cent; P = 0.030). There was no difference in duration of hospital day or 30-day postoperative complications (including anastomotic leak) between the STIMULAX and control groups. Routine postoperative use of multimodal laxatives after elective colorectal surgery results in earlier recovery of gastrointestinal function and reduces the incidence of prolonged POI. Registration number: ACTRN12618001261202 (www.anzctr.org.au).

Increased risk of complications in smokers undergoing reversal of diverting ileostomy.

Diverting ileostomy (DI) is utilised in rectal cancer surgery to mitigate the effects of anastomotic leak. The aim of this study was to assess the clinical risk factors associated with post-operative complications of DI reversal. A single-centre retrospective analysis of patients who underwent surgical resection for rectal cancer and subsequent DI reversal between January 2012 and December 2020 was undertaken. Medical records were reviewed to extract clinical, operative and pathologic details and post-operative complications according to the Clavien-Dindo classification. Univariate and multivariable analyses were undertaken to assess risk factors associated with post-operative complications of DI reversal. One hundred and twenty-six adult patients who underwent DI reversal were included of which 49 had a post-operative complication (39%). The most common complication was prolonged post-operative ileus, which occurred in 24 patients (19%). On multivariable analysis smoking was significantly associated with overall complications (odds ratio [OR]=5.60, 95% confidence interval [CI] 1.90-16.52, p=0.0018), and high Clavien-Dindo (2-5) category complications (OR=4.60, 95% CI 1.81-11.68, p=0.0013). In addition, patients who received adjuvant chemotherapy were less likely to have a reversal of DI complication (OR=0.43, 95% CI 0.19-0.94, p=0.0342) and less likely to have a high Clavien-Dindo (2-5) category complication (OR=0.44, 95% CI 0.20-0.93, p=0.0311). Smokers who have undergone surgical resection of rectal cancer have a significantly increased risk of post-operative complications after DI reversal. In these patients, the importance of smoking cessation must be emphasised. The decreased complication rate observed in patients who received adjuvant chemotherapy was an unexpected finding.

Effect of intraoperative fluid volume on postoperative ileus after robot-assisted radical cystectomy

This study aimed to investigate the effect of intraoperative fluid volume on the postoperative ileus (POI) recovery period. A retrospective review of the Korean robot-assisted radical cystectomy database identified 718 patients who underwent robot-assisted radical cystectomy (RARC). Regression analyses were performed to identify the associations between the amount of intraoperative fluid administration (crystalloid/colloid/total), POI period (time to flatus/bowel movements), and length of hospital stay (LOS) after adjusting for covariates. In addition, we analyzed the risk factors for gastrointestinal complications and prolonged POI using a logistic regression model. An increasing volume of the administered crystalloid/total fluid was associated with prolonged POI (crystalloid R2 = 0.0725 and P < 0.0001; total amount R2 = 0.0812 and P < 0.0001), and the total fluid volume was positively associated with the LOS (R2 = 0.099 and P < 0.0001). The crystalloid amount was a risk factor for prolonged POI (P < 0.001; odds ratio, 1.361; 95% confidence interval, 1.133–1.641; P < 0.001). In the context of RARC, increased intravenous fluids are associated with prolonged POI and longer LOS.

Complications and postoperative ileus in laparoscopic versus open colectomy: A retrospective cohort study

Background: Postoperative complications are a major concern after colorectal surgery, and can lead to an increased burden on patients and the healthcare system. Complications include postoperative ileus (POI) and prolonged postoperative ileus (PPOI). There are well-established risk factors and potential modifiable risk factors that affect the incidence of POI and PPOI, including invasive techniques, operative difficulty, perioperative blood loss, and delayed mobilization. We compared the incidence of POI, PPOI, and other postoperative complications between laparoscopic colectomy and open colectomy. Methods: This retrospective review investigates 120 patients who underwent either laparoscopic or open colectomy in King AbdulAziz University Hospital in Jeddah, Saudi Arabia, between January 2016 and June 2019. Data were collected from patients’ electronic medical records. Patients were classified into laparoscopic and open colectomy groups. The main outcomes of interest were POI, PPOI and the overall complication rate. These outcomes were calculated and compared between the two groups. Results: The overall incidence of POI and PPOI was 4.2% and 15%, respectively. There was a higher incidence of POI in the laparoscopic approach group (7.2% vs. 1.5%, P=0.03); however, the incidence of PPOI was higher in the open approach group (20% vs. 9.1%, P=0.03). The open surgery group showed a higher rate of overall complications (P=0.001). The mean estimated blood loss was lower in the laparoscopy group (139.09±145.83 vs. 343.85±307.78 mL; P&lt;0.001). Significant earlier mobilization was observed in the laparoscopic group (3.12±1.77 vs. 5.39±3.48 days; P&lt;0.001). Conclusion: The incidence of PPOI was significantly different depending on the surgical approach; however, the laparoscopy group tolerated regular diet earlier and had better outcomes regarding postoperative complications. The laparoscopic approach was associated with earlier ambulation and was more cost-effective based on the length of the hospital stay. Further randomized studies are required to confirm superiority of the laparoscopic approach in terms of postoperative recovery.

Differences in effectiveness and use of laparoscopic surgery in locally advanced colon cancer patients

Patients with locally advanced colon cancer have worse outcomes. Guidelines of various organizations are conflicting about the use of laparoscopic colectomy (LC) in locally advanced colon cancer. We determined whether patient outcomes of LC and open colectomy (OC) for locally advanced (T4) colon cancer are comparable in all colon cancer patients, T4a versus T4b patients, obese versus non-obese patients, and tumors located in the ascending, descending, and transverse colon. We used data from the 2013–2015 American College of Surgeons’ National Surgical Quality Improvement Program. Patients were diagnosed with nonmetastatic pT4 colon cancer, with or without obstruction, and underwent LC (n = 563) or OC (n = 807). We used a composite outcome score (mortality, readmission, re-operation, wound infection, bleeding transfusion, and prolonged postoperative ileus); length of stay; and length of operation. Patients undergoing LC exhibited a composite outcome score that was 9.5% lower (95% CI − 15.4; − 3.5) versus those undergoing OC. LC patients experienced a 11.3% reduction in postoperative ileus (95% CI − 16.0; − 6.5) and an average of 2 days shorter length of stay (95% CI − 2.9; − 1.0). Patients undergoing LC were in the operating room an average of 13.5 min longer (95% CI 1.5; 25.6). We found no evidence for treatment heterogeneity across subgroups (p > 0.05). Patients with locally advanced colon cancer who receive LC had better overall outcomes and shorter lengths of stay compared with OC patients. LC was equally effective in obese/nonobese patients, in T4a/T4b patients, and regardless of the location of the tumor.

Prolonged Postoperative Ileus in Colorectal Surgery Within an Enhanced Recovery Protocol: a Multivariate Analysis

Prolonged Postoperative Ileus in Colorectal Surgery Within an Enhanced Recovery Protocol: a Multivariate Analysis

Safety and Suitability of the SmartPill® after Abdominal Surgery: Results of the Prospective, Two-Armed, Open-Label PIDuSA Trial

Introduction: Postoperative ileus (POI) is a common complication after abdominal surgery. Until today, an evidence-based treatment of prolonged POI is still lacking, which can be attributed to the poor quality of clinical trials. Various different surrogate markers used to define POI severity are considered to be the cause of low-quality trials making it impossible to derive treatment recommendation. The SmartPill®, which is able to record pH values, temperature and pressure after ingestion, could be an ideal tool to measure transit times and peristalsis and therefore analyze POI severity. Unfortunately, the device has no approval for postoperative use due to safety concerns. The primary objective of the study is to determine safety of the SmartPill® in patients undergoing surgery. Secondary objectives were the quality of the recorded data and the suitability of the SmartPill® for analyzing intestinal motility after different surgical procedures. Methods: The PIDuSA Study is a prospective, 2-arm, open-label trial. At the end of surgery, the SmartPill® was applied to 49 patients undergoing abdominal surgery having a high risk for impaired intestinal motility and 15 patients undergoing extra-abdominal surgery. Patients were visited daily to access safety data of the SmartPill® on the basis of adverse and serious adverse events (AEs/SAEs). Suitability and data quality were investigated by analyzing data completeness and feasibility to determine transit times and peristalsis for all sections of the gastrointestinal tract. Results: In total, 179 AEs and 8 SAEs were recorded throughout the study affecting 42 patients in the abdominal (158 AEs) and 9 patients in the extra-abdominal surgery group (21 AEs, p = 0.061); none of them were device related. Primary capsule failure was observed in 5 patients, ultimately resulting in an impossibility of data analysis in only 3 patients (4.4%). 9% of the recorded data were incomplete due to the patient’s incompliance in keeping the receiver close to the body. In 3 patients (4.4%), isolated small bowel transit could not be determined due to pH alterations as a result of prolonged POI. Discussion: Our study demonstrates that the use of the SmartPill® is safe after surgery but requires a reasonable patient compliance to deliver meaningful data. An objective analysis of transit times and peristalsis was possible irrespective of type and site of surgery in over 95% indicating that the SmartPill® has the potential to deliver objective parameters for POI severity in future clinical trials. However, in some patients with prolonged POI, analysis of small bowel transit could be challenging.

Randomized Controlled Trial: Perioperative Dexamethasone Reduces Excessive Postoperative Inflammatory Response and Ileus After Surgery for Inflammatory Bowel Disease

An excessive postoperative inflammatory response is common after surgery for inflammatory bowel disease (IBD) and may be associated with an increased incidence of postoperative ileus. This study assessed the role of perioperative dexamethasone in postoperative ileus after IBD surgery. Patients undergoing elective IBD surgery were randomized to either an intravenous 8-mg dose of dexamethasone (n = 151) or placebo (n = 151) upon induction of anesthesia. The primary outcome was the incidence of prolonged postoperative ileus. Secondary outcomes included incidence of reported nausea or vomiting, time to first passage of flatus and stool, GI-2 recovery, postoperative pain, length of stay, and surgical complications. An intention-to-treat analysis revealed that patients who received dexamethasone exhibited a lower incidence of prolonged postoperative ileus (22.5% vs 38.4%; P = 0.003), shorter time to first passage of stool (28 vs 48 h, P < 0.001), GI-2 recovery (72 vs 120 h; P < 0.001), reduced postoperative length of stay (9.0 vs 10.0 d; P = 0.002), and less postoperative pain (P < 0.05) compared with controls. Moreover, there were no significant differences in postoperative nausea or vomiting (P = 0.531), major postoperative complications (P = 0.165), or surgical site infections (P = 0.337) between the groups. A benefit was only observed in patients with Crohn's disease, restored bowel continuity, colon/rectal resections, and those who underwent open operations. A single, intravenous 8-mg dose of dexamethasone upon induction of anesthesia reduced the incidence of prolonged postoperative ileus, the intensity of postoperative pain, and shortened the postoperative length of stay for IBD patients undergoing elective surgery. ClinicalTrials.gov: NCT03456752.

Variable Gut Function Recovery After Right vs. Left Colectomy May Be Due to Rectosigmoid Hyperactivity.

It is established that gut function recovers slower after right vs. left colectomies with higher rates of prolonged post-operative ileus (PPOI), but the reason is unclear. Development of PPOI is multifactorial. A recent manometry study in right colectomy patients showed that the distal colon becomes hyperactive after surgery with predominantly cyclic motor patterns (CMPs). In this perspective, we evaluate the hypothesis that the slower gut recovery after right hemicolectomy could be induced by a functional obstruction due to hyperactive CMPs.

Relationships between serum electrolyte concentrations and ileus: A joint clinical and mathematical modeling study

AimProlonged postoperative ileus (PPOI) occurs in around 15% of patients after major abdominal surgery, posing a significant clinical and economic burden. Significant fluid and electrolyte changes may occur peri‐operatively, potentially contributing to PPOI; however, this association has not been clearly elucidated. A joint clinical‐theoretical study was undertaken to evaluate peri‐operative electrolyte concentration trends, their association with ileus, and predicted impact on bioelectrical slow waves in interstitial cells of Cajal (ICC) and smooth muscle cells (SMC).MethodsData were prospectively collected from 327 patients undergoing elective colorectal surgery. Analyses were performed to determine associations between peri‐operative electrolyte concentrations and prolonged ileus. Biophysically based ICC and SMC mathematical models were adapted to evaluate the theoretical impacts of extracellular electrolyte concentrations on cellular function.ResultsPostoperative day (POD) 1 calcium and POD 3 chloride, sodium were lower in the PPOI group (p < 0.05), and POD3 potassium was higher in the PPOI group (p < 0.05). Deficits beyond the reference range in PPOI patients were most notable for sodium (Day 3: 29.5% ileus vs. 18.5% no ileus, p = 0.04). Models demonstrated an 8.6% reduction in slow‐wave frequency following the measured reduction in extracellular NaCl on POD5, with associated changes in cellular slow‐wave morphology and amplitude.ConclusionLow serum sodium and chloride concentrations are associated with PPOI. Electrolyte abnormalities are unlikely to be a primary mechanism of ileus, but their pronounced effects on cellular electrophysiology predicted by modeling suggest these abnormalities may adversely impact motility recovery. Resolution and correction of electrolyte abnormalities in ileus may be clinically relevant.