Incidence of prolonged postoperative ileus after colorectal surgery: a systematic review and meta-analysis

Influence of Robotic Rectal Resection Versus Laparoscopic Rectal Resection on Postoperative Ileus: A Single-center Experience

AIM

This study was performed to clarify the relationship between robotic rectal resection and postoperative ileus (POI) by comparing robotic surgery with laparoscopic surgery.

MATERIALS AND METHODS

We retrospectively reviewed 238 patients who underwent robotic (n=41) or laparoscopic (n=197) rectal resection for rectal cancer in our institution from January 2013 to June 2020. First, we compared the background factors and short-term surgical outcomes between robotic and laparoscopic surgery. Next, we investigated the postoperative complications of robotic and laparoscopic rectal resection. Finally, we identified the risk factors for POI following rectal cancer resection.

RESULTS

The percentages of patients with an Rb tumor location, treatment by abdominoperitoneal resection/intersphincteric resection/low anterior resection, a temporary diverting ileostomy, and a long operation time were significantly higher in robotic than laparoscopic surgery (P<0.0001,P=0.0002,P=0.0078, andP=0.0001, respectively). There was no significant difference in any individual postoperative complication between robotic and laparoscopic surgery. Risk factors for POI were male sex (P=0.0078), neoadjuvant chemoradiotherapy (P=0.0007), an Rb tumor location (P=0.0005), treatment by abdominoperitoneal resection/intersphincteric resection/low anterior resection (P=0.0044), a temporary diverting ileostomy (P<0.0001), and operation time of ≥240 minutes (P=0.0024). Notably, robotic surgery was not a risk factor for POI following rectal resection relative to laparoscopic surgery.

CONCLUSION

Although patients who underwent robotic surgery had more risk factors for POI, the risk of POI was similar between robotic and laparoscopic rectal resection.

A comparison of extracorporeal side to side or end to side anastomosis following a laparoscopic right hemicolectomy for colon cancer

Background

This study aimed to investigate whether an extracorporeal side‐to‐side (SS) or end‐to‐side (ES) stapled anastomosis impacts short‐term and long‐term outcomes after an oncological laparoscopic right hemicolectomy.

Methods

A retrospective cohort study of prospectively collected data from two Victorian tertiary referral hospitals was performed. Patients who underwent oncological resection for colorectal cancer between February 2010 and September 2020 were selected from the colorectal neoplasia database. Patients were divided into two groups depending on the type of stapled anastomosis: Group 1 (functional end‐to‐end/side‐to‐side (SS)); and Group 2 (end‐to‐side (ES)). Primary outcomes were anastomotic leak, postoperative ileus, mortality and morbidity, length of stay post‐surgery, readmission to hospital, and 30‐day mortality.

Results

This large case series of 1040 patients (SS = 625, ES = 415) demonstrated that the type of stapling technique impacted operative duration and postoperative ileus rates. Patients in the SS group had a faster operation of 108 min rather than 130 min in the ES group (p < 0.001). The SS group were more likely to experience a post‐operative ileus (p < 0.001) with no impact on length of stay (SS, 7 days versus ES, 7 days; p = 0.14). There were no differences between the two groups with respect to lymph node yield, lymph node ratio, anastomotic leaks, return to theatre, 30‐day mortality and 5‐year overall survival.

Discussion

The type of extracorporeal stapled anastomosis following an oncological laparoscopic right hemicolectomy has minimal impact on morbidity and survival outcomes; however, a side‐to‐side stapled anastomosis is more likely to be a faster operation with a higher postoperative ileus rate.

Impact of Early Oral Feeding on Nasogastric Tube Reinsertion After Elective Colorectal Surgery: A Systematic Review and Meta-Analysis

Background

Colorectal cancer is a common malignant tumor appearing in the gastrointestinal tract. Surgical resection is recognized as the best means to improve patient survival. However, it is controversial whether early oral feeding (EOF) after elective colorectal resection demonstrates safety and efficacy in concerned clinical outcomes.

Methods

We searched PubMed, Embase, Cochrane Library, and CNKI from inception to September 2021. Two authors independently screened the retrieved records and extracted data. EOF was defined as feeding within 24 h after surgery, while traditional oral feeding (TOF) was defined as feeding that started after the gastrointestinal flatus or ileus was resolved. The primary outcome was nasogastric tube insertion, and the secondary outcomes were the length of hospital stay and total complications. Categorical data were combined using odds ratio (OR), and continuous data were combined using mean difference (MD).

Results

We screened 10 studies from 34 records after full-text reading, with 1,199 patients included in the analysis. Nasogastric tube reinsertion (OR 1.69; 95% CI 1.08 to 2.64, p=0.02) was more frequent in the EOF group, and older ages (&gt;60 years) were associated with higher risk of nasogastric tube reinsertion (OR 2.05; 95% CI 1.05 to 3.99, p = 0.04). Reduced length of hospital stay (MD −1.76; 95% CI −2.32 to −1.21; p &lt; 0.01) and the rate of total complications (OR 0.49; 95% CI 0.37 to 0.65, p &lt; 0.01) were observed in EOF compared with TOF.

Conclusions

EOF was safe and effective for patients undergoing elective colorectal surgery, but the higher rate of nasogastric tube reinsertion compared with TOF should not be ignored.

Comparison of prolonged postoperative ileus between laparoscopic right and left colectomy under enhanced recovery after surgery: a propensity score matching analysis

Background

There were differences in the recovery of bowel function and prolonged postoperative ileus (PPOI) between laparoscopic right colectomy (RC) and left colectomy (LC) under the guidance of enhanced recovery after surgery.

Methods

We selected 870 patients who underwent elective laparoscopic colectomy from June 2016 to December 2021, including 272 patients who had RC and 598 who had LC. According to 1:1 proportion for propensity score matching and correlation analysis, 247 patients who had RC and 247 who had LC were finally enrolled.

Results

The incidence of PPOI in all patients was 13.1%. Age, sex, smoking habit, preoperative serum albumin level, operation type, and operation time were the important independent risk factors based on multivariate logistic regression and correlation analysis for PPOI (p<0.05). Age, sex, body mass index, preoperative serum albumin level, operation time, and degree of differentiation between the two groups were significantly different before case matching (p<0.05). There were no statistically significant differences in baseline characteristics and preoperative biochemical parameters between the two groups after case matching (p>0.05). The incidence of PPOI in patients who had RC was 21.9%, while that in patients who had LC was 13.0%. The first flatus, first semi-liquid, and length of stay in LC patients were lower than those in RC patients (p<0.05).

Conclusion

The return of bowel function in LC was faster than that in RC, and the incidence of PPOI was relatively lower. Therefore, caution should be taken during the early feeding of patients who had laparoscopic RC.

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.

Risk Factors for Post-operative Ileus: A Retrospective Study in Tertiary Referral Hospital in Indonesia

Background: Postoperative ileus is a complication that may result in the longer duration of stay and decreases the quality of life of patients. Previous studies have found some factors related to postoperative ileus. This study aimed to determine the risk factor of postoperative ileus in laparotomic resection and anastomosis surgery. Methods: Patients who underwent laparotomic resection and anastomosis surgery during January 2019 – July 2020 were included. Postoperative ileus was diagnosed in fourth day after surgery. The variables included in this study are age, gender, BMI, pathology site, duration of surgery, type of anastomosis, length of resection. Result: Fifty laparotomic resection and anastomosis surgery patients were included in this study, 50% of subjects is patients with postoperative ileus. Patient aged 65 years old or older had a higher incidence postoperative ileus (68% vs 28%; RR 2.3 95% CI: 1.23-4.33; p value: 0.010). Study also found duration of surgery 180 minutes or longer also had higher incidence postoperative ileus (79% vs 36%; RR: 2.49 95% CI: 1.20-5.15; p value: 0.010). Conclusion: This study concludes that age 65 years old or older and duration of surgery 180 minutes or longer are significant risk factor to postoperative ileus in laparotomic resection and anastomosis surgery patients.

Self-administered succus entericus reinfusion before ileostomy closure improves short-term outcomes

OBJECTIVE

The study aims to assess whether reinfusion of succus entericus prior to ileostomy closure can decrease postoperative length of stay and ameliorate low anterior resection score.

METHODS

This study is a retrospective analysis based on prospectively collected data. Patients were screened from May 2016 to November 2019. A total of 30 patients who underwent reinfusion with succus entericus (SER) were enrolled in the SER group and 42 patients without SER were enrolled in the non-SER group.

RESULTS

There was no significant difference in the incidence of postoperative ileus between succus entericus reinfusion (SER) group and the control group. Time to first passage of flatus or stool after surgery in the SER group (27.9 ± 6.02 h) is significantly shorter than the control group (32.3 ± 6.26, hours p = 0.004). Compared with the control group (5.52 (4.0-7.0) days), postoperative length of stay in the SER group was 4.90 (3.0-7.0)days (p = 0.009). As for low anterior resection score(LARS), the SER group had a lower score 1 week after discharge than the control group (p = 0.034). However, 1 month after discharge, the LARS in the two groups had no significant difference.

CONCLUSIONS

Self-administered succus entericus reinfusion is a feasible prehabilitation management for outpatients and can improve better outcomes. Compared with non-reinfusion group, succus enterius reinfusion group displays significantly shorter time for gastrointestinal function recovery and postoperative hospital stay without increasing complication, and it can bring better quality of life in a short term.

The role of laparoscopic surgery in the surgical management of gallbladder carcinoma: A systematic review and meta-analysis

Previous studies have explored the role of laparoscopic surgery (LS) in the surgical management of gallbladder carcinoma (GBC) and obtained satisfactory outcomes versus conventional open surgery. However, most of them either included a small number of patients or mainly focused on the early-staged lesions. Therefore, their results were less statistical powerful and a more comprehensive evaluation on the role of LS in GBC is warranted. A thorough database searching was performed in PubMed, EMBASE and Cochrane Library for comparative studies between the laparoscopic and open approach in the surgical management of GBC and 18 comparative studies were finally identified. RevMan 5.3 and Stata 13.0 software were used for statistical analyses. Pooled results revealed that patients in the laparoscopic group recovered faster with less intraoperative hemorrhage and less postoperative morbidity. Comparable operative time, overall recurrence rate, R0 resection rate, lymph node yield, intraoperative gallbladder violation rate and postoperative survival outcomes were also acquired. Regarding the debating issue of port-site recurrence, a significantly higher incidence of port-site recurrence was observed in laparoscopic group. However, having excluded studies on incidental gallbladder carcinoma, the subsequent pooled result showed no significant difference. Considering the inherent inconsistency of the surgical indication between laparoscopic and open surgeries and the deficiency of advanced lesions, we drew a conclusion that laparoscopic surgery seems to be only safe and feasible for early- or middle-staged lesions. Upcoming random controlled trials or comparative studies with equivalent surgical indication focused on advanced lesions are warranted for further evaluation.

Post-operative ileus: definitions, mechanisms and controversies

Post-operative ileus (POI) is a syndrome of impaired gastrointestinal transit which occurs following abdominal surgery. There are few effective targeted therapies for ileus, and research has been limited by inconsistent definitions and an incomplete understanding of the underlying pathophysiology. Despite considerable effort, there remains no widely-adopted definition of ileus, and recent work has identified variation in outcome reporting is a major source of heterogeneity in clinical trials. Outcomes should be clearly-defined, clinically-relevant, and reflective of the underlying biology, impacts on hospital resources and quality of life. Further collaborative efforts will be needed to develop consensus definitions and a core outcome set for postoperative gastrointestinal recovery. Investigation into the pathophysiology of POI has been hindered by use of low-resolution techniques and difficulties linking cellular mechanisms to dysmotility patterns and clinical symptoms. Recent evidence has suggested the common assumption of post-operative GI paralysis is incorrect, and that the distal colon becomes hyperactive following surgery. The post-operative inflammatory response is important in the pathophysiology of ileus, but the time course of this in humans remains unclear, with the majority of evidence coming from animal models. Future work should investigate dysmotility patterns underlying ileus, and identify biomarkers which may be used to diagnose, monitor and stratify patients with ileus.

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

BACKGROUND

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.

METHOD

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.

RESULTS

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.

CONCLUSION

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.

Evaluation of a Broad-Spectrum Partially Automated Adverse Event Surveillance System: A Potential Tool for Patient Safety Improvement in Hospitals With Limited Resources

OBJECTIVE

The aim of the study was to evaluate the sensitivity and resource efficiency of a partially automated adverse event (AE) surveillance system for routine patient safety efforts in hospitals with limited resources.

METHODS

Twenty-eight automated triggers from the hospital information system's clinical and administrative databases identified cases that were then filtered by exclusion criteria per trigger and then reviewed by an interdisciplinary team. The system, developed and implemented using in-house resources, was applied for 45 days of surveillance, for all hospital inpatient admissions (N = 1107). Each trigger was evaluated for its positive predictive value (PPV). Furthermore, the sensitivity of the surveillance system (overall and by AE category) was estimated relative to incidence ranges in the literature.

RESULTS

The surveillance system identified a total of 123 AEs among 283 reviewed medical records, yielding an overall PPV of 52%. The tool showed variable levels of sensitivity across and within AE categories when compared with the literature, with a relatively low overall sensitivity estimated between 21% and 44%. Adverse events were detected in 23 of the 36 AE categories defined by an established harm classification system. Furthermore, none of the detected AEs were voluntarily reported.

CONCLUSIONS

The surveillance system showed variable sensitivity levels across a broad range of AE categories with an acceptable PPV, overcoming certain limitations associated with other harm detection methods. The number of cases captured was substantial, and none had been previously detected or voluntarily reported. For hospitals with limited resources, this methodology provides valuable safety information from which interventions for quality improvement can be formulated.

Targets for Intervention? Preoperative Predictors of Postoperative Ileus After Colorectal Surgery in an Enhanced Recovery Protocol

BACKGROUND

Postoperative ileus occurs in up to 30% of colorectal surgery patients and is associated with increased length of stay, costs, and morbidity. While Enhanced Recovery Protocols seek to accelerate postoperative recovery, data on modifiable preoperative factors associated with postoperative ileus in this setting are limited. We aimed to identify preoperative predictors of postoperative ileus following colorectal surgery in Enhanced Recovery Protocols, to determine new intervention targets.

METHODS

We performed a retrospective single-center cohort study of patients ≥ 18 years old who underwent colorectal surgery via Enhanced Recovery Protocols (7/2015-7/2017). Postoperative ileus was defined as nasogastric tube insertion postoperatively or nil-per-os by postoperative day 4. Preoperative risk factors including comorbidities and medication use were identified using multivariable stepwise logistic regression.

RESULTS

Of 530 patients, 14.9% developed postoperative ileus. On univariate analysis of perioperative and postoperative factors, postoperative ileus patients had increased psychiatric illness, antidepressant and antipsychotic use, American Society of Anesthesiologists classification, ileostomy creation, postoperative opioid use, complications, surgery duration, and length of stay (p < 0.05). Multivariable logistic regression model for preoperative factors identified psychiatric illness, preoperative antipsychotic use, and American Society of Anesthesiologists classification ≥ 3 as significant predictors of postoperative ileus (p < 0.05).

DISCUSSION

Postoperative ileus remains a common complication following colorectal surgery under Enhanced Recovery Protocols. Patients with pre-existing psychiatric comorbidities and preoperative antipsychotic use may be a previously overlooked cohort at increased risk for postoperative ileus. Additional research and preoperative interventions within Enhanced Recovery Protocols to reduce postoperative ileus for this higher-risk population are needed.

Reducing ileus after colorectal surgery: A network meta-analysis of therapeutic interventions

BACKGROUND

Several treatment strategies for avoiding post-operative ileus have been evaluated in randomised controlled trials. This network meta-analysis aimed to explore the relative effectiveness of these different therapeutic interventions on ileus outcome measures.

METHODS

A systematic literature review was performed to identify randomized controlled trials (RCTs) comparing treatments for post-operative ileus following colorectal surgery. A Bayesian network meta-analysis was performed using the Markov chain Monte Carlo method. Direct and indirect comparisons of all regimens were simultaneously compared using random-effects network meta-analysis.

RESULTS

A total of 48 randomised controlled trials were included in this network meta-analysis reporting on 3614 participants. Early feeding was found to be the best treatment for time to solid diet tolerance and length of hospital stay with a probability of P = 0.96 and P = 0.47, respectively. Early feeding resulted in significantly shorter time to solid diet tolerance (Mean Difference (MD) 58.85 h; 95% Credible Interval (CrI) -73.41, -43.15) and shorter length of hospital stay (MD 2.33 days; CrI -3.51, -1.18) compared to no treatment. Epidural analgesia was ranked best treatment for time to flatus (P = 0.29) and time to stool (P = 0.268). Epidural analgesia resulted in significantly shorter time to flatus (MD -18.88 h; CrI -33.67, -3.44) and shorter time to stool (MD -26.05 h; 95% CrI -66.42, 15.65) compared to no intervention. Gastrograffin was ranked best treatment to avoid the requirement for post-operative nasogastric tube insertion (P = 0.61) however demonstrated limited efficacy (OR 0.50; CrI 0.143, 1.621) compared to no intervention. Nasogastric and nasointestinal tube insertion, probiotics, and acupuncture were found to be least efficacious as interventions to reduce ileus.

CONCLUSION

This network meta-analysis identified early feeding as the most efficacious therapeutic intervention to reduce post-operative ileus in patients undergoing colorectal surgery, in addition to highlighting other therapies that require further investigation by high quality study. In patients undergoing colorectal surgery, emphasis should be placed on early feeding as soon as can be appropriately initiated to support the return of gastrointestinal motility.

Acupuncture combined with multidisciplinary care for recovery after traumatic multiple rib fractures: a prospective feasibility cohort study

INTRODUCTION

Acute pain significantly delays early physiological recovery and results in chronic functional disability in patients with traumatic multiple rib fractures (MRFs). This prospective cohort study aimed to investigate the feasibility of acupuncture combined with multidisciplinary care during recovery in patients with traumatic MRFs.

METHODS

Twenty patients with traumatic MRFs who were admitted to a regional trauma centre in South Korea were enrolled. A combination of acupuncture and multidisciplinary inpatient ward management was provided at the trauma ward. Patients were permitted to continue acupuncture treatments at outpatient clinics for 3 months after the traumatic events. Clinical outcomes, including pain, acute physiological recovery, quality of life, patient satisfaction with the care provided, respiratory function and use of opioids, were evaluated up to 6 months after trauma.

RESULTS

Seventeen (85%) participants completed the 6-month follow-up. One patient withdrew consent during admission due to discomfort after three sessions of acupuncture. The proportion of patients with above-moderate level of pain decreased from 95% at baseline to 41% at 6 months. Quality of life appeared to deteriorate consistently throughout the study period. Around 80% of respondents expressed satisfaction with the acupuncture treatments and stated that they found acupuncture to be acceptable. Over 94% of respondents reported slight or considerable improvement.

CONCLUSION

The provision of acupuncture combined with multidisciplinary care for recovery in patients with traumatic MRFs was feasible in a regional trauma centre in South Korea. Randomised trials are needed to investigate the role of acupuncture combined with multidisciplinary care in the future.

TRIAL REGISTRATION NUMBER

KCT0002911 (Clinical Research Information Service).

Factors associated with diet failure after colon cancer surgery

BACKGROUND

Since the introduction of Enhanced Recovery After Surgery (ERAS), early diet after surgery has been emphasized and clinical outcomes have improved, though vomiting has been reported frequently. We defined diet failure based on clinical manifestation and images after colon cancer surgery and attempted to analyze underlying risk factors by comparing the early diet group with the conventional diet group.

METHODS

All consecutive patients underwent colectomy with curative intent at a single institution between August 2015 and July 2017. The early diet group was started on soft diet on the second day after surgery, while the conventional group started the same after flatulence. The primary outcome was the difference in the incidence of diet failure between the two groups. Secondary outcomes were analyzed to determine risk factors for diet failure and readmission due to ileus.

RESULTS

Overall, 293 patients were included in the conventional diet group and 231 in the early diet group. There were no significant differences between the two groups, except for shorter hospital stays in the early diet group (median 8 days, p < 0.001). A total of 46 patients (early diet, n = 20; conventional diet, n = 26, p = 1.000) had diet failure. Multivariate analysis showed that operation time (odds ratio [OR] 1.76, 95% confidence interval [CI] 1.33-2.32) and side-to-side anastomosis compared with the end-to-end method (OR 4.41, 95% CI 2.10-9.24) were independent risk factors for diet failure. Sixteen patients were readmitted due to ileus that occurred within 2 months after surgical operation. Diet resumption time was not a risk factor for both diet failure and ileus.

CONCLUSIONS

Early diet resumption does not increase diet failure and can reduce hospital stay. Anastomosis and operation time may be related to diet failure. Our study suggests that evaluation of surgical factors is important for postoperative recovery, and well-designed follow-up studies are needed.

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.

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.

Noninvasive vagus nerve stimulation to reduce ileus after major colorectal surgery: early development study

AIM

Vagus nerve stimulation has emerged as a plausible intervention to reduce ileus after surgery. An early development study was undertaken with the aim of exploring the feasibility of self-administered, noninvasive vagus nerve stimulation (nVNS) after major colorectal surgery.

METHOD

A parallel-group, randomized controlled trial was undertaken between 1 January 2018 and 31 August 2019. Forty patients undergoing colorectal surgery for malignancy were allocated equally to Sham and Active stimulation groups. Electrical vagus nerve stimulation was self-administered bilaterally over the cervical surface landmarks for 5 days before and after surgery. Outcomes of interest were postoperative complications and adverse events measured using the Clavien-Dindo scale, treatment compliance, device usability according to the Systems Usability Scale (SUS) and clinical measures of bowel recovery.

RESULTS

Forty patients were randomized and one withdrew, leaving 39 for analysis. Postoperative complications occurred in 9/19 (47.4%) participants receiving Sham and 11/20 (55.0%) receiving Active stimulation and were mostly minor. Compliance with treatment before surgery was 4.7 ± 0.9 days out of 5 days in the Sham group and 4.7 ± 1.1 in the Active group. Compliance with treatment after surgery was 4.1 ± 1.1 and 4.4 ± 1.5, respectively. Participants considered the intervention to be 'acceptable' according to the SUS. The most prominent differences in bowel recovery were days to first flatus (2.35 ± 1.32 vs 1.65 ± 0.88) and tolerance of solid diet (2.18 ± 2.21 vs 1.75 ± 0.91) for Sham and Active groups, respectively.

CONCLUSION

This study supports the safety, treatment compliance and usability of self-administered nVNS in patients undergoing major colorectal surgery.

Postoperative Ileus after Stimulation with Probiotics before Ileostomy Closure

Loop ileostomy closure after colorectal surgery is often associated with Postoperative ileus, with an incidence between 13-20%. The aim of this study is to evaluate the efficacy and safety of preoperative stimulation of the efferent loop with probiotics prior to ileostomy closure in patients operated on for colorectal carcinoma. For this, a prospective, randomized, double-blind, controlled study is designed. All patients who underwent surgery for colorectal carcinoma with loop ileostomy were included. Randomized and divided into two groups, 34 cases and 35 controls were included in the study. Postoperative ileus, the need for nasogastric tube insertion, the time required to begin tolerating a diet, restoration of bowel function, and duration of hospital stay were evaluated. The incidence of Postoperative ileus was similar in both groups, 9/34 patients stimulated with probiotics and 10/35 in the control group (CG) with a p = 0.192. The comparative analysis showed a direct relationship between Postoperative ileus after oncological surgery and Postoperative ileus after reconstruction surgery, independently of stimulation. Postoperative ileus after closure ileostomy is independent of stimulation of the ileostomy with probiotics through the efferent loop. There seem to be a relationship between Postoperative ileus after reconstruction and the previous existence of Postoperative ileus after colorectal cancer surgery.

Subtotal colectomy, extended right hemicolectomy, left hemicolectomy, or splenic flexure colectomy for splenic flexure tumors: a network meta-analysis

AIM

To perform a network meta-analysis of the current literature to evaluate the short-term and long-term outcomes of four operations for splenic flexure tumors.

METHODS

An electronic literature search of PubMed, Baidu Scholar, EMBASE, and Cochrane Central Register of Controlled Trials databases was performed up to August 2020. A Bayesian network meta-analysis was utilized to compare the outcomes involved in subtotal colectomy (STC), extended right hemicolectomy (ERHC), standard left hemicolectomy (LHC), and splenic flexure colectomy (SFC) by using R software.

RESULTS

A total of 10 non-randomized studies were included in this meta-analysis. There was no statistically significant difference among these 4 surgical techniques in terms of the utilization rate of minimally invasive surgery, reoperative surgery, anastomotic dehiscence, mortality, the proportion of patients with the number of lymph nodes harvested ≥ 12, local recurrence, distant recurrence and overall survival. Although ERHC was associated with a higher risk of postoperative ileus (ERHC vs SFC, OR = 6.4, 95% CI 1.4-45.0, P = 0.019), it has an advantage of a higher rate of primary anastomosis (ERHC vs LHC, OR = 4.2, 95% CI 1.3-18.0, P = 0.019) and a non-significant trend for lower anastomotic dehiscence when compared with more restrict resections.

CONCLUSION

SFC, LHC, ERHC and STC for the curative resection of splenic flexure tumors provide similar survival. An individualized surgical plan considering both long-term and short-term outcomes is necessary to select the appropriate operations.

State-of-the-art colorectal disease: postoperative ileus

PURPOSE

Postoperative Ileus (POI) remains an important complication for patients after abdominal surgery with an incidence of 10-27% representing an everyday issue for abdominal surgeons. It accounts for patients' discomfort, increased morbidity, prolonged hospital stays, and a high economic burden. This review outlines the current understanding of POI pathophysiology and focuses on preventive treatments that have proven to be effective or at least show promising effects.

METHODS

Pathophysiology and recommendations for POI treatment are summarized on the basis of a selective literature review.

RESULTS

While a lot of therapies have been researched over the past decades, many of them failed to prove successful in meta-analyses. To date, there is no evidence-based treatment once POI has manifested. In the era of enhanced recovery after surgery or fast track regimes, a few approaches show a beneficial effect in preventing POI: multimodal, opioid-sparing analgesia with placement of epidural catheters or transverse abdominis plane block; μ-opioid-receptor antagonists; and goal-directed fluid therapy and in general the use of minimally invasive surgery.

CONCLUSION

The results of different studies are often contradictory, as a concise definition of POI and reliable surrogate endpoints are still absent. These will be needed to advance POI research and provide clinicians with consistent data to improve the treatment strategies.

The association of alvimopan treatment with postoperative outcomes after abdominal surgery: A systematic review across different surgical procedures and contexts of perioperative care

BACKGROUND

Alvimopan is a Food and Drug Administration-approved treatment to accelerate gastrointestinal recovery after abdominal surgery; however, benefits may vary across different procedures and contexts of care. The purpose of this study is to summarize the evidence regarding the effect of alvimopan on postoperative outcomes after abdominal surgery.

METHODS

Major databases (Medline, Embase, Biosis, Cochrane, Web of Science, and Scopus) were searched for randomized controlled trials and nonrandomized studies comparing alvimopan versus control. Risk of bias was assessed using Cochrane's risk of bias tool 2.0 (for randomized controlled trials) and Risk of Bias in Nonrandomized Studies-of Intervention tool (for nonrandomized studies). Results were appraised descriptively as heterogeneity in reporting and risk of bias hindered meta-analysis. Quality of evidence across different surgical procedures and contexts of care (ie, open versus minimally invasive surgery, traditional care versus enhanced recovery pathway) was evaluated using Grading of Recommendations Assessment, Development, and Evaluation.

RESULTS

Nine randomized controlled trials and 35 nonrandomized studies were identified. Evidence of low to moderate certainty supports that alvimopan reduces length of stay and improves gastrointestinal recovery after open bowel resection and open radical cystectomy. Limited evidence supports alvimopan for surgeries not listed in Food and Drug Administration labels (ie, total abdominal hysterectomy and retroperitoneal lymph node dissection). Similar effects were observed in traditional and enhanced recovery pathway settings, but enhanced recovery pathway elements varied across studies. There is very low certainty of evidence supporting alvimopan for patients undergoing minimally invasive surgery.

CONCLUSION

Evidence supports that alvimopan improves outcomes after open bowel resection and open radical cystectomy. Benefits for patients undergoing minimally invasive surgery and treated in contemporary enhanced recovery pathway settings remain uncertain. These findings contribute important new knowledge to inform evidence-based alvimopan prescribing.

The Effect of an Enhanced Recovery Program on Elective Right Hemicolectomies for Crohn's Disease vs. Colon Cancer: A Retrospective Cohort Analysis

BACKGROUND

Enhanced recovery after surgery (ERAS) protocols are widely employed in colorectal surgery, successful in reducing postoperative morbidities and hospital length of stay (LOS). However, ERAS effects on the inflammatory bowel disease population remain unclear. This study examines the postoperative course of both Crohn's disease (CD) and colon cancer (CC) patients after elective right hemicolectomies and compares the effectiveness of ERAS protocol.

METHODS

A retrospective analysis was performed on patients with CD and CC undergoing elective right hemicolectomies and ileocecectomies from January 2014 through June 2016 (pre-ERAS) and January 2017 through April 2019 (post-ERAS) from a single tertiary care center. Patient demographics and perioperative variables were examined, including prolonged postoperative ileus (PPOI), hospital LOS, and 30-day readmission.

RESULTS

98 CC patients and 91 CD patients met the inclusion criteria. The pre-ERAS CC and post-ERAS CC cohorts were significantly different: post-ERAS had fewer patients with congestive heart failure and chronic obstructive pulmonary disease and had higher albumin levels. The pre-ERAS CC cohort had significantly longer operative durations and higher rates of concomitant procedures than the post-ERAS CC cohort. Both patients with CC and CD had a reduction in LOS with implementation of ERAS, decreasing by 2.24 days (P = .002) and 1.21 days (P = .038), respectively. There was a reduction in rates of organ space infections with CD (pre .132, post .00, P = .007). There was a trend towards an increased rate of PPOI with CD (Pre .079, Post .226, P = .062).

DISCUSSION

The ERAS protocol significantly reduced LOS for both groups, without increasing 30-day readmission rates or other morbidities.

No Coil® placement in patients undergoing left hemicolectomy and low anterior resection for colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is the most common tumor of the gastrointestinal tract. Anastomotic leak (AL) and prolonged postoperative ileus (PPOI) are two important complications of colorectal surgery. In this observational retrospective study, we evaluated the positive effects of transanal tube No Coil® in patients with CRC undergoing low anterior resection (LAR) and left hemicolectomy (LC).

METHODS

Thirty-eight cases and forty controls resulted eligible for the final sample. No Coil® placement (SapiMed Spa, Alessandria, Italy) was considered an inclusion criteria for the case group. No Coil® was placed immediately after the end of surgical treatment.

RESULTS

PPOI was significantly more frequent in the control group. AL was evident in 1 patient (2.6%) of cases and 3 patients (7.5%) of controls. No statistical difference was found in AL occurrence between groups. POI days and AL resulted associated with hospital stay. POI days were negatively associated with No Coil placement and positively with AL.

CONCLUSION

With our preliminary data, we suggest that No Coil® placement can be considered as a valuable procedure assisting colorectal surgery, but further studies are required to confirm and enlarge actual evidence.

Are right-sided colectomies for neoplastic disease at increased risk of primary postoperative ileus compared to left-sided colectomies? A coarsened exact matched analysis

INTRODUCTION

The objective of this study was to determine whether right-sided colectomies (RC) were associated with a higher incidence of primary postoperative ileus (pPOI) compared to left-sided colectomies (LC).

METHODS

Patients who underwent elective colectomy for neoplastic disease between 2012 and 2016 were identified using the American College of Surgeons National Surgical Quality Improvement Program database. RC and LC were defined as having an ileocolic or colocolic/colorectal anastomosis, respectively. Coarsened Exact Matching (CEM) was used to balance the two groups (1:1) on important confounders. The association between type of colectomy and pPOI, defined as POI in the absence of intra-abdominal sepsis, was then assessed in a multiple logistic regression analysis of the matched data.

RESULTS

Of 40,636 patients who underwent a colectomy for neoplastic disease, 15,231 underwent a RC and 25,405 a LC. After CEM, 12,949 matched patients remained in each group, and all important confounders were well balanced. The incidence of pPOI was higher in the RC group (11.5% vs. 8.8%, p < 0.001). On multiple logistic regression, RC was associated with a 35% higher odds of developing pPOI compared to LC (OR 1.35, 95% CI 1.25-1.47). RC was also associated with increased risk for NSQIP-defined major morbidity (OR 1.10, 95% CI 1.01-1.20), 30-day readmission (OR 1.16, 95% CI 1.06-1.27), and increased length of stay (β = 0.16 days, 95% CI 0.11-0.22).

CONCLUSION

pPOI is more common after RC than LC. Future research should aim at better understanding the pathophysiology behind this increased risk and identifying interventions to mitigate pPOI in this population.

Prediction of Postoperative Ileus in Patients With Colorectal Cancer by Preoperative Gut Microbiota

Background

Ileus and postoperative ileus (POI) are common complications of colorectal cancer (CRC). However, little is known about the gut microbiota associated with ileus.

Method

Differences in gut microbiota were evaluated by 16S rRNA gene sequencing. We characterized the gut microbiota in 85 CRC patients (cohort 1) and detected differences, and an independent cohort composed of 38 CRC patients (cohort 2) was used to evaluate the results.

Results

The gut microbiota of CRC patients with and without ileus exhibited large differences in alpha- and beta-diversities and bacterial taxa. The Firmicutes-to-Bacteroidetes ratio and microbial dysbiosis index (MDI) showed greater dysbiosis among ileus patients than among those without ileus. According to the location of CRC, the difference in gut microbiota between patients with and without ileus was more obvious in those with distal CRC than in those with proximal CRC. Finally, Faecalibacterium was significantly reduced in the postoperative perioperative period in patients with ileus. Thus, we used Faecalibacterium as a biomarker for predicting perioperative or POI: the AUC value was 0.74 for perioperative ileus and 0.67 for POI that appeared at 6 months after hospital discharge. The predictive power was evaluated in Cohort 2, with an AUC value of 0.79.

Conclusion

These findings regarding difference of gut microbiota in postoperative CRC patients may provide a theoretical basis for the use of microbiota as biomarkers for the prediction of POI.

Postoperative Ileus and Postoperative Gastrointestinal Tract Dysfunction: Pathogenic Mechanisms and Novel Treatment Strategies Beyond Colorectal Enhanced Recovery After Surgery Protocols

Postoperative ileus (POI) and postoperative gastrointestinal tract dysfunction (POGD) are well-known complications affecting patients undergoing intestinal surgery. GI symptoms include nausea, vomiting, pain, abdominal distention, bloating, and constipation. These iatrogenic disorders are associated with extended hospitalizations, increased morbidity, and health care costs into the billions and current therapeutic strategies are limited. This is a narrative review focused on recent concepts in the pathogenesis of POI and POGD, pipeline drugs or approaches to treatment. Mechanisms, cellular targets and pathways implicated in the pathogenesis include gut surgical manipulation and surgical trauma, neuroinflammation, reactive enteric glia, macrophages, mast cells, monocytes, neutrophils and ICC's. The precise interactions between immune, inflammatory, neural and glial cells are not well understood. Reactive enteric glial cells are an emerging therapeutic target that is under intense investigation for enteric neuropathies, GI dysmotility and POI. Our review emphasizes current therapeutic strategies, starting with the implementation of colorectal enhanced recovery after surgery protocols to protect against POI and POGD. However, despite colorectal enhanced recovery after surgery, it remains a significant medical problem and burden on the healthcare system. Over 100 pipeline drugs or treatments are listed in Clin.Trials.gov. These include 5HT4R agonists (Prucalopride and TAK 954), vagus nerve stimulation of the ENS-macrophage nAChR cholinergic pathway, acupuncture, herbal medications, peripheral acting opioid antagonists (Alvimopen, Methlnaltexone, Naldemedine), anti-bloating/flatulence drugs (Simethiocone), a ghreline prokinetic agonist (Ulimovelin), drinking coffee, and nicotine chewing gum. A better understanding of the pathogenic mechanisms for short and long-term outcomes is necessary before we can develop better prophylactic and treatment strategies.

Changes to gastrointestinal function after surgery for colorectal cancer

Bowel function is increasingly considered as an important outcome for patients undergoing surgery for colorectal cancer. Increasing technical skills and technological advances have meant fewer patients require a long-term stoma but this comes at the cost, often, of poor function. With a larger range of treatment options available for a given cancer, both function and oncology should be considered in parallel when counselling patients before surgery. In the perioperative phase, bowel function can be improved with minimally invasive surgery and enhanced recovery after surgery protocols, with limited evidence for targeted medical therapies. Early detection and sound management of surgical complications such as anastomotic leak and stricture can mitigate their adverse effects on bowel function. Long-term gastrointestinal dysfunction manifests as diarrhoea and low anterior resection syndrome for colon and rectal cancer respectively. Multi-modal strategies for low anterior resection syndrome are emerging to improve significantly quality of life after restorative rectal cancer surgery.

Perspectives on paralytic ileus

Paralytic ileus is the condition where the motor activity of the bowel is impaired, usually not associated with a mechanical cause. Although the condition may be self‐limiting, it is serious and if prolonged and untreated will result in death in much the same way as in acute mechanical obstruction. Management of paralytic ileus depends on the knowledge of the most likely cause and the perceived chance of resolution without operation. Postoperative ileus is the single largest factor influencing length of hospital stay after bowel resection, and has great implications for patients and resource utilization. Early diagnosis and correct management is essential in reducing complications. This article briefly outlined the plausible pathophysiological mechanisms and clinical implications of paralytic ileus.

Intracorporeal versus extracorporeal anastomosis for right colectomy does not affect gastrointestinal recovery within an enhanced recovery after surgery program

INTRODUCTION

Delayed gastrointestinal (GI) recovery remains a significant morbidity after colorectal surgery. Intracorporeal anastomosis for right colectomy may hasten GI recovery. Therefore, the objective of this study was to determine the effect of intracorporeal versus extracorporeal anastomosis on GI recovery after elective laparoscopic right colectomy within an established ERAS program.

METHODS

Adult patients undergoing elective laparoscopic right colectomy at a single high-volume institution from 07/2014 to 12/2018 were reviewed. Patients were divided into two groups: intracorporeal (IC) and extracorporeal (EC). The primary outcome was time to GI-3 defined as days to tolerance of solid diet and first flatus/bowel movement. Prolonged postoperative ileus (PPOI) was defined as GI-3 not met by postoperative day 4. Secondary outcomes were length of stay (LOS) and overall 30-day complications. Sensitivity analysis was performed using coarsened exact matching to account for unmeasured confounding. Multiple regression was performed using a Cox proportional hazard model to identify predictors of GI recovery.

RESULTS

A total of 346 patients were reviewed, of which 226 were included (71IC, 155EC). Patient characteristics were well balanced between groups: mean age was 64.9 years (SD 15.9), BMI was 26.3 (SD 5.7), 38.1% of patients had ASA ≥ 3, and 78.3% underwent surgery for neoplasms. IC anastomosis was associated with longer operative duration (165 min (SD 40); 144 min (SD 48), p = 0.002). There was no difference in the median time to GI-3 (IC 2 days [IQR1-2]; EC 2 days [IQR2-3], p = 0.135). The incidence of PPOI (IC 8.5%; EC 10.3%, p = 0.659), superficial SSI (4.2% vs. 5.8%, p = 0.757), deep SSI (2.8% vs. 5.2%, p = 0.729), and median LOS (3 days [IQR 2-4] vs. 3 [IQR 3-5], p = 0.059) were also similar. On multivariate analysis, IC anastomosis did not independently predict faster GI recovery (HR 0.98, 95% CI 0.71-1.34). Similar results were observed in the matched cohort (185 patients (61IC, 124EC)).

CONCLUSION

In this study, IC anastomosis was not associated with faster GI recovery or reduced complication rate compared to EC anastomosis. Longer term studies may be required to determine the potential benefits of IC anastomosis.

Comparison between the cervical and abdominal vagus nerves in mice, pigs, and humans

BACKGROUND

Vagus nerve (VN) stimulation is currently evaluated as a novel approach to treat immune-mediated disorders. The optimal stimulation parameters, however, largely depend on the VN composition potentially impacting on its clinical translation. Hence, we evaluated whether morphological differences exist between the cervical and abdominal VNs across different species.

MATERIALS AND METHODS

The cervical and abdominal VNs of mouse, pig, and humans were stained for major basic protein and neurofilament F to identify the percentage and size of myelinated and non-myelinated fibers.

RESULTS

The percentage of myelinated fibers was comparable between species, but was higher in the cervical VN compared with the abdominal VN. The cervical VN contained 54 ± 4%, 47 ± 7%, and 54 ± 7% myelinated fibers in mouse, pig, and humans, respectively. The myelinated fibers consisted of small-diameter (mouse: 71%, pig: 80%, and humans: 63%), medium-diameter (mouse: 21%, pig: 18%, and humans: 33%), and large-diameter fibers (mouse: 7%, pig: 2%, and humans: 4%). The abdominal VN predominantly contained unmyelinated fibers (mouse: 93%, pig: 90%, and humans: 94%). The myelinated fibers mainly consisted of small-diameter fibers (mouse: 99%, pig: 85%, and humans: 74%) and fewer medium-diameter (mouse: 1%, pig: 13%, and humans: 23%) and large-diameter fibers (mouse: 0%, pig: 2%, and humans: 3%).

CONCLUSION

The VN composition was largely similar with respect to myelinated and unmyelinated fibers in the species studied. Human and porcine VNs had a comparable diameter and similar amounts of fibrous tissue and contained multiple fascicles, implying that the porcine VN may be suitable to optimize stimulation parameters for clinical trials.

Pretreatment with transcutaneous electrical acupoint stimulation to prevent postoperative ileus in patients undergoing laparoscopic colon surgery: study protocol for a randomised controlled trial

INTRODUCTION

Postoperative ileus (POI), a common complication after surgery, severely affects postoperative recovery. It is unclear whether pretreatment with transcutaneous electrical acupoint stimulation (TEAS) can improve recovery from POI. This trial will evaluate the effects of pretreatment with TEAS on POI.

METHODS AND ANALYSIS

This will be a prospective, randomised controlled trial. American Society of Anesthesiologists (ASA) physical status classification I-III level patients, aged 18-75 years and scheduled for laparoscopic colon surgery, will be included in the study. It is planned that 146 subjects will be randomised to the TEAS and sham TEAS (STEAS) groups. The groups will undergo two sessions of TEAS/STEAS daily for 3 days before surgery, with a final TEAS/STEAS treatment 30 min before anaesthesia. The primary endpoint of the study will be time to first defaecation. Secondary endpoints will include time to first flatus, time to tolerance of oral diet, GI-2 (composite outcome of time to first defaecation and time to tolerance of oral diet), time to independent walking, length of hospital stay, postoperative pain Visual Analogue Scale score on the first 3 days after surgery, analgesic requirements, complications and plasma concentrations of interferon-β (IFN-β), IFN-γ, interleukin-6 (IL-6) and IL-1β. Multiple linear regression will be used to identify independent predictors of outcome measures.

ETHICS AND DISSEMINATION

This study has been approved by the Chinese Registered Clinical Trial Ethics Review Committee (No. ChiECRCT-20170084). The results of the trial will be published in an international peer-reviewed journal.

TRIAL REGISTRATION NUMBER

This study has been registered with the Chinese Clinical Trial Registry (No. ChiCTR-INR-17013184).

TRIAL STATUS

The study was in the recruitment phase at the time of manuscript submission.

Guidelines for Perioperative Care in Cytoreductive Surgery (CRS) with or without hyperthermic IntraPEritoneal chemotherapy (HIPEC): Enhanced Recovery After Surgery (ERAS®) Society Recommendations - Part II: Postoperative management and special considerations

BACKGROUND

Enhanced recovery after surgery (ERAS) pathways have been shown to considerably reduce complications, length of stay and costs after most of surgical procedures by standardised application of best evidence-based perioperative care. The aim was to elaborate dedicated recommendations for cytoreductive surgery (CRS) ± hyperthermic intraperitoneal chemotherapy (HIPEC) in a two-part series of guidelines based on expert consensus. The present part II of the guidelines highlights postoperative management and special considerations.

METHODS

The core group assembled a multidisciplinary panel of 24 experts involved in peritoneal surface malignancy surgery representing the fields of general surgery (n = 12), gynaecological surgery (n = 6), and anaesthesia (n = 6). Experts systematically reviewed and summarized the available evidence on 72 identified perioperative care items, following the GRADE (grading of recommendations, assessment, development, evaluation) system. Final consensus (defined as ≥50%, or ≥70% of weak/strong recommendations combined) was reached by a standardised 2-round Delphi process, regarding the strength of recommendations.

RESULTS

Response rates were 100% for both Delphi rounds. Quality of evidence was evaluated high, moderate low and very low, for 15 (21%), 26 (36%), 29 (40%) and 2 items, respectively. Consensus was reached for 71/72(98.6%) items. Strong recommendations were defined for 37 items. No consensus could be reached regarding the preemptive use of fresh frozen plasma.

CONCLUSION

The present ERAS recommendations for CRS ± HIPEC are based on a standardised expert consensus process providing clinicians with valuable guidance. There is an urgent need to produce high quality studies for CRS ± HIPEC and to prospectively evaluate recommendations in clinical practice.

Alterations of the Rectal Microbiome Are Associated with the Development of Postoperative Ileus in Patients Undergoing Colorectal Surgery

BACKGROUND

The most common complications after colorectal surgery, postoperative ileus, surgical site infections, and anastomotic leaks continue to occur despite advances in surgical technique and enhanced recovery pathways. Preclinical studies have documented that intestinal bacteria play a role in the development of these complication, yet human data is lacking. Here we hypothesized that patients that develop ileus, surgical site infection, and/or anastomotic leak following colorectal surgery harbor a specific preoperative gut microbiome.

METHODS

We performed a prospective cohort study on 101 patients undergoing colon or rectal resection at the Mayo Clinic. Rectal samples were collected preoperatively and on the ward on postoperative day two. The bacterial community from each sample was characterized by 16S rRNA and associated with the development of complications.

RESULTS

The rectal microbiome collected from patients in the operating room (p = .003) and on postoperative day two (p = .001) was significantly difference in patients whom later developed postoperative ileus compared with patients that had a normal return of bowel function. Patients whom developed ileus showed increased abundance of Bacteroides spp., Parabacteroides spp., and Ruminococcus spp., bacteria that are associated with promoting intestinal inflammation. There were no differences in the microbiome in patients that developed surgical site infections or anastomotic leaks.

CONCLUSIONS

In this pilot study, patients that develop postoperative ileus harbor a specific gut microbiome during the perioperative period. These findings demonstrate that the preoperative bacterial composition may predispose patients to the development of ileus and that perioperative manipulation of the gut bacteria may provide a novel method to promote normal return of bowel function.

Preoperative albumin levels predict prolonged postoperative ileus in gastrointestinal surgery

BACKGROUND

Prolonged postoperative ileus (PPOI) is a prolonged state of "pathological" gastrointestinal (GI) tract dysmotility. There are relatively few studies examining the influence of preoperative nutritional status on the development of PPOI in patients who underwent GI surgery. The association between preoperative albumin and PPOI has not been fully studied. We hypothesized that preoperative albumin may be an independent indicator of PPOI.

AIM

To analyze the role of preoperative albumin in predicting PPOI and to establish a nomogram for clinical risk evaluation.

METHODS

Patients were drawn from a prospective hospital registry database of GI surgery. A total of 311 patients diagnosed with gastric or colorectal cancer between June 2016 and March 2017 were included. Potential predictors of PPOI were analyzed by univariate and multivariable logistic regression analyses, and a nomogram for quantifying the presence of PPOI was developed and internally validated.

RESULTS

The overall PPOI rate was 21.54%. Advanced tumor stage and postoperative opioid analgesic administration were associated with PPOI. Preoperative albumin was an independent predictor of PPOI, and an optimal cutoff value of 39.15 was statistically calculated. After adjusting multiple variables, per unit or per SD increase in albumin resulted in a significant decrease in the incidence of PPOI of 8% (OR = 0.92, 95%CI: 0.85-1.00, P = 0.046) or 27% (OR = 0.73, 95%CI: 0.54-0.99, P = 0.046), respectively. Patients with a high level of preoperative albumin (≥ 39.15) tended to experience PPOI compared to those with low levels (< 39.15) (OR = 0.43, 95%CI: 0.24-0.78, P = 0.006). A nomogram for predicting PPOI was developed [area under the curve (AUC) = 0.741] and internally validated by bootstrap resampling (AUC = 0.725, 95%CI: 0.663-0.799).

CONCLUSION

Preoperative albumin is an independent predictive factor of PPOI in patients who underwent GI surgery. The nomogram provided a model to screen for early indications in the clinical setting.

Incidence and Risk Factors for Severity of Postoperative Ileus After Colorectal Surgery: A Prospective Registry Data Analysis

BACKGROUND

Defining severe postoperative ileus in terms of consequences could help physicians standardize the management of this condition. The recently described classification based on consequences requires further investigation. The aim of this study was to obtain a snapshot of postoperative ileus in patients undergoing colorectal surgery within enhanced recovery programs and to identify factors associated with non-severe and severe postoperative ileus.

METHODS

This prospective registry data analysis was conducted in 40 centers in five different countries. A total of 786 patients scheduled for colorectal surgery within enhanced recovery programs were included. The primary endpoint was the incidence rate of postoperative ileus as defined by Vather et al. RESULTS: A total of 121 patients experienced postoperative ileus (15.4%). Non-severe POI occurred in 48 patients (6.1%), and severe postoperative ileus occurred in 73 patients (9.3%). In multivariate analysis, the male gender and intra-abdominal complications were associated with severe postoperative ileus: odd ratio (OR) = 2.03 [95% confidence interval (CI) 1.14-3.59], p = 0.01 and OR = 3.60 [95% CI 1.75-7.40], p < 0.0001, respectively. Conversely, open laparotomy and urinary retention were associated with non-severe POI: OR = 3.03 [95% CI 1.37-6.72], p = 0.006 and OR = 2.70 [95% CI 0.89-8.23], p = 0.08, respectively.

CONCLUSIONS

Postoperative ileus occurred in 15% of patients after colorectal surgery within enhanced recovery programs. For 60% of patients, this was considered severe. The physiopathology of these two entities could be different, severe POI being linked to intraabdominal complication, while non-severe POI being linked with risk factors for "primary" POI. The physician should pay attention to male patients having POI after colorectal surgery and look for features evocating intraabdominal complications.

Potential Association Between Perioperative Fluid Management and Occurrence of Postoperative Ileus

BACKGROUND

Postoperative ileus remains an issue after colorectal surgery delaying recovery and increasing the length of hospital stay and costs.

OBJECTIVE

The purpose of this study was to analyze the impact of perioperative fluid management on ileus occurrence after colorectal surgery within a fully implemented enhanced recovery pathway.

DESIGN

This was a retrospective cohort study of a prospectively maintained institutional database.

SETTINGS

The study was conducted at a tertiary academic facility with fully implemented standardized enhanced recovery pathway over the entire study period.

PATIENTS

All of the consecutive elective major colorectal resections for benign or malign indications between 2011 and 2016 were included.

MAIN OUTCOME MEASURES

Postoperative ileus was defined as the need for nasogastric tube reinsertion. Perioperative fluid management and surgical outcome were compared between patients presenting with ileus and those without. Potential risk factors for ileus were identified through multinomial logistic regression.

RESULTS

Postoperative ileus occurred in 377 (9%) of 4205 included patients at day 4 (interquartile range, 2-5 d). Intraoperatively, ileus patients received 3.2 ± 2.6 L of fluids, whereas the remaining patients received 2.5 ± 1.7 L (p < 0.001). Weight gain was 3.8 ± 7.1 kg in ileus patients versus 3.0 ± 6.6 kg (p = 0.272) in the remaining patients at postoperative day 1, 4.4 ± 6.5 kg versus 3.1 ± 7.0 kg (p = 0.028) at postoperative day 2, and 1.8 ± 6.0 kg versus 0.0 ± 6.0 kg at discharge (p = 0.002). The multivariable model including all significant (p < 0.05) demographic, fluid management-related, and surgical parameters retained postoperative day 0 fluids of >3 L (OR = 1.65 (95% CI, 1.13-2.41); p = 0.009), postoperative day 2 weight gain of >2.5 kg (OR = 1.49 (95% CI, 1.01-2.21); p = 0.048), and occurrence of postoperative complications (OR = 2.00 (95% CI, 1.39-2.90); p < 0.001) as independent risk factors for ileus.

LIMITATIONS

This study was limited by its retrospective design. Fluid management depends on patient-, disease-, and surgery-related factors and cannot be generalized and extrapolated.

CONCLUSIONS

Fluid overload and occurrence of postoperative complications were independent risk factors for postoperative ileus. This calls for action to keep perioperative fluids below suggested thresholds. See Video Abstract at http://links.lww.com/DCR/B54. ASOCIACIÓN POTENCIAL ENTRE EL MANEJO DEL LÍQUIDO PERIOPERATORIO Y EL SUCESO DE ÍLEO POSTOPERATORIO: El íleo postoperatorio sigue siendo un problema después de una cirugía colorrectal que retrasa la recuperación y aumenta la duración de la estancia hospitalaria y los costos.Analizar el impacto del manejo del líquido perioperatorio en la incidencia de íleo después de la cirugía colorrectal dentro de una vía de recuperación mejorada totalmente implementada.Estudio de cohorte retrospectivo de una base de datos institucional mantenida prospectivamente.Centro académico terciario con una ruta de recuperación mejorada estandarizada completamente implementada durante todo el período del estudio.Se incluyeron todas las resecciones colorrectales mayores electivas consecutivas para indicaciones benignas o malignas entre 2011 y 2016.El íleo postoperatorio se definió como la necesidad de reinserción de la sonda nasogástrica. El manejo del líquido perioperatorio y el resultado quirúrgico se compararon entre los pacientes con íleo y los que no. Los posibles factores de riesgo para el íleo se identificaron mediante regresión logística multinominal.El íleo postoperatorio se ocurrió en 377 (9%) de los 4205 pacientes incluidos al cuarto día (RIC 2-5). Intraoperatoriamente, los pacientes con íleo recibieron 3.2 ± 2.6 L de líquidos, mientras que los pacientes restantes recibieron 2.5 ± 1.7 L (p < 0.001). El aumento de peso fue de 3.8 ± 7.1 kg en pacientes con íleo versus 3 ± 6.6 kg (p = 0.272) en los pacientes restantes en el día postoperatorio 1, 4.4 ± 6.5 kg vs. 3.1 ± 7 kg (p = 0.028) en el día postoperatorio 2 y 1.8 ± 6 kg versus a 0 ± 6 kg al tiempo de alta hospitalaria (p = 0.002). El modelo multivariable que incluye todos los parámetros demográficos, del manejo de líquidos y quirúrgicos significativos (p <0.05) mantuvo líquidos del día 0 después de la operación de> 3L (proporción de probabilidad 1.65, intervalo de confianza del 95% 1.13-2.41, p = 0.009), ganancia de peso de > 2.5 kg en el dia postoperatorio 2 (proporción de probabilidad 1.49, 95% intervalo de confianza 1.01-2.21, p = 0.048) y aparición de complicaciones postoperatorias (proporción de probabilidad 2, 95% intervalo de confianza 1.39-2.9, p <0.001) como factores de riesgo independientes para íleo.Diseño retrospectivo. El manejo de líquidos depende de factores relacionados con el paciente, la enfermedad y la cirugía, y no puede generalizarse ni extrapolarse.La sobrecarga de líquidos y la aparición de complicaciones postoperatorias fueron factores de riesgo independientes para el íleo postoperatorio. Esto requiere medidas para mantener los líquidos perioperatorios por debajo de los umbrales sugeridos. Vea el Video del Resumen en http://links.lww.com/DCR/B54.

Feasibility of perioperative volatile organic compound breath testing for prediction of paralytic ileus following laparoscopic colorectal resection

BACKGROUND

Despite implementation of enhanced recovery after surgery (ERAS) and laparoscopic techniques, postoperative ileus (POI) remains frequent after colorectal surgery, impacting the patient, their recovery and health-care resources. Presently there are no tests that reliably predict or enable early POI diagnosis. Volatile organic compounds (VC) are products of human and microbiota cellular metabolism and we hypothesised that a detectable alteration occurs in POI.

METHOD

This was a prospective observational study of patients undergoing laparoscopic colorectal resection within an established ERAS programme. Standardized end-expiratory breath sampling was performed on the morning of surgery and on the first three postoperative mornings. The concentrations of VCs commonly found in intestinal gas were analysed using selected ion flow tube mass spectrometry and GastroCH₄ ECK®. Feasibility data, bowel preparation, postoperative oral intake, POI and 30-day morbidity were recorded.

RESULTS

Of the 75 potentially eligible patients, 58 (77%) agreed to participate. Per-protocol breath sampling was successfully completed in 94%. There were no analytical failures. Baseline and postoperative concentrations of VCs were broadly comparable and were not altered by bowel preparation or postoperative oral intake. POI developed in 14 (29%) patients. Preoperative ammonia concentration was higher in patients who developed POI [830 parts per billion (ppb) vs 510 ppb, P = 0.027]. There was an increase in the concentration of acetic acid detected on day 2 in patients who developed POI (99 ppb vs 171 ppb, P = 0.021).

CONCLUSION

Repeated VC breath sampling and analysis is feasible in the perioperative setting. An elevated ammonia concentration on the morning of surgery may be a potential predictor of POI.

Animal Models for Functional Gastrointestinal Disorders

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

A systematic review and meta-analysis of baseline risk factors for the development of postoperative ileus in patients undergoing gastrointestinal surgery

INTRODUCTION

Postoperative ileus occurs frequently following abdominal surgery. Identification of groups at high risk of developing ileus before surgery may allow targeted interventions. This review aimed to identify baseline risk factors for ileus.

METHODS

A systematic review was conducted with reference to PRISMA and MOOSE guidelines. It was registered on PROSPERO (CRD42017068697). Searches of MEDLINE, EMBASE and CENTRAL were undertaken. Studies reporting baseline risk factors for the development of postoperative ileus based on cohort or trial data and published in English were eligible for inclusion. Dual screening of abstracts and full texts was undertaken. Independent dual extraction was performed. Bias assessment was undertaken using the quality in prognostic studies tool. Meta-analysis using a random effects model was undertaken where two or more studies assessed the same variable.

FINDINGS

Searches identified 2,430 papers, of which 28 were included in qualitative analysis and 12 in quantitative analysis. Definitions and incidence of ileus varied between studies. No consistent significant effect was found for association between prior abdominal surgery, age, body mass index, medical comorbidities or smoking status. Male sex was associated with ileus on meta-analysis (odds ratio 1.12, 95% confidence interval 1.02-1.23), although this may reflect unmeasured factors. The literature shows inconsistent effects of baseline factors on the development of postoperative ileus. A large cohort study using consistent definitions of ileus and factors should be undertaken.

Role of the intestinal microbiome in colorectal cancer surgery outcomes

OBJECTIVES

Growing evidence supports the role of the intestinal microbiome in the carcinogenesis of colorectal cancers, but its impact on colorectal cancer surgery outcomes is not clearly defined. This systematic review aimed to analyze the association between intestinal microbiome composition and postoperative complication and survival following colorectal cancer surgery.

METHODS

A systematic review was conducted according to the 2009 PRISMA guidelines. Two independent reviewers searched the literature in a systematic manner through online databases, including Medline, Scopus, Embase, Cochrane Oral Health Group Specialized Register, ProQuest Dissertations and Theses Database, and Google Scholar. Human studies investigating the association between the intestinal microbiome and the short-term (anastomotic leakage, surgical site infection, postoperative ileus) and long-term outcomes (cancer-specific mortality, overall and disease-free survival) of colorectal cancer surgery were selected. Patients with any stage of colorectal cancer were included. The Newcastle-Ottawa scale for case-control and cohort studies was used for the quality assessment of the selected articles.

RESULTS

Overall, 8 studies (7 cohort studies and 1 case-control) published between 2014 and 2018 were included. Only one study focused on short-term surgical outcomes, showing that anastomotic leakage is associated with low microbial diversity and abundance of Lachnospiraceae and Bacteroidaceae families in the non-cancerous resection lines of the stapled anastomoses of colorectal cancer patients. The other 7 studies focused on long-term oncological outcomes, including survival and cancer recurrence. The majority of the studies (5/8) found that a higher level of Fusobacterium nucleatum adherent to the tumor tissue is associated with worse oncological outcomes, in particular, increased cancer-specific mortality, decreased median and overall survival, disease-free and cancer-specific survival rates. Also a high abundance of Bacteroides fragilis was found to be linked to worse outcomes, whereas the relative abundance of the Prevotella-co-abundance group (CAG), the Bacteroides CAG, and the pathogen CAG as well as Faecalibacterium prausnitzii appeared to be associated with better survival.

CONCLUSIONS

Based on the limited available evidence, microbiome composition may be associated with colorectal cancer surgery outcomes. Further studies are needed to elucidate the role of the intestinal microbiome as a prognostic factor in colorectal cancer surgery and its possible clinical implications.

Cutaneous Patches to Monitor Myoelectric Activity of the Gastrointestinal Tract in Postoperative Pediatric Patients

PURPOSE

Limited means exist to assess gastrointestinal activity in pediatric patients postoperatively. Recently, myoelectric gastrointestinal activity recorded by cutaneous patches has been shown in adult patients to be predictive of clinical return of gastrointestinal function postoperatively. The aim of this case series is to demonstrate the feasibility of this system in pediatric patients and to correlate myoelectric signals with return of bowel function clinically.

METHODS

Pediatric patients undergoing abdominal surgery were recruited to have wireless patches placed on the abdomen within two hours postoperatively. Myoelectric data were transmitted wirelessly to a mobile device with a user-interface and forwarded to a cloud server where processing algorithms identified episodes of motor activity, quantified their parameters and nominally assigned them to specific gastrointestinal organs based on their frequencies.

RESULTS

Three patients (ages 5 months, 4 year, 16 year) were recruited for this study. Multiple patches were placed on the older subjects, while the youngest had a single patch due to space limitations. Rhythmic signals of the stomach, small intestine, and colon could be identified in all three subjects. Patients showed gradual increase in myoelectric intestinal and colonic activity leading up to the first recorded bowel movement.

CONCLUSION

Measuring myoelectric intestinal activity continuously using a wireless patch system is feasible in a wide age range of pediatric patients. The increase in activity over time correlated well with the patients' return of bowel function. More studies are planned to determine if this technology can predict return of bowel function or differentiate between physiologic ileus and pathologic conditions.

Nomogram to predict prolonged postoperative ileus after gastrectomy in gastric cancer

BACKGROUND

Prolonged postoperative ileus (PPOI) is one of the common complications in gastric cancer patients who underwent gastrectomy. Evidence on the predictors of PPOI after gastrectomy is limited and few prediction models of nomogram are used to estimate the risk of PPOI. We hypothesized that a predictive nomogram can be used for clinical risk estimation of PPOI in gastric cancer patients.

AIM

To investigate the risk factors for PPOI and establish a nomogram for clinical risk estimation.

METHODS

Between June 2016 and March 2017, the data of 162 patients with gastrectomy were obtained from a prospective and observational registry database. Clinical data of patients who fulfilled the criteria were obtained. Univariate and multivariable logistic regression models were performed to detect the relationship between variables and PPOI. A nomogram for PPOI was developed and verified by bootstrap resampling. The calibration curve was employed to detect the concentricity between the model probability curve and ideal curve. The clinical usefulness of our model was evaluated using the net benefit curve.

RESULTS

This study analyzed 14 potential variables of PPOI in 162 gastric cancer patients who underwent gastrectomy. The incidence of PPOI was 19.75% in patients with gastrectomy. Age older than 60 years, open surgery, advanced stage (III-IV), and postoperative use of opioid analgesic were independent risk factors for PPOI. We developed a simple and easy-to-use prediction nomogram of PPOI after gastrectomy. This nomogram had an excellent diagnostic performance [area under the curve (AUC) = 0.836, sensitivity = 84.4%, and specificity = 75.4%]. This nomogram was further validated by bootstrapping for 500 repetitions. The AUC of the bootstrap model was 0.832 (95%CI: 0.741-0.924). This model showed a good fitting and calibration and positive net benefits in decision curve analysis.

CONCLUSION

We have developed a prediction nomogram of PPOI for gastric cancer. This novel nomogram might serve as an essential early warning sign of PPOI in gastric cancer patients.

Predictors of ileus following colorectal resections

BACKGROUND

Ileus following colorectal surgery is a significant burden for healthcare and can be challenging to manage. This study aims to evaluate risk factors for postoperative ileus in patients undergoing colorectal surgery.

METHODS

Patients who underwent colorectal resections for any diagnosis were identified from our institutional database between 2009 and 2014. Patient demographics, pre-operative comorbidities, and operation-related variables were compared in patients with and without ileus within 30 days after surgery.

RESULTS

A total of 5369 patients were identified with a mean age of 53 years. 892 patients (16.6%) developed postoperative ileus. Males were twice as likely (p < 0.001) and patients with anastomosis were 1.4 times more likely to develop ileus compared to those without (p < 0.001). Laparoscopic surgery and younger age were associated with lower ileus risk. Patients with colorectal cancer, Crohn's disease, and ulcerative colitis diagnoses were all more likely to develop postoperative ileus compared to patients with diverticular disease.

CONCLUSIONS

Evaluation of factors such as male gender, older age, anastomosis formation, diagnosis of cancer and inflammatory bowel disease, can help facilitate earlier diagnosis of postoperative ileus and may require consideration of prophylactic therapy.

Prolonged postoperative ileus in gastric surgery: Is there any difference between laparoscopic and open surgery?

BACKGROUND

Prolonged postoperative ileus (PPOI) is a common complication after abdominal surgery, but data about risk factors of PPOI for patients with gastric cancer are rare. We sought to investigate the impact of laparoscopic versus open surgery for PPOI after gastric cancer surgery.

METHODS

A retrospective cohort study was conducted using a registry database consecutively collected from June 2016 to March 2017. PPOI was defined as no bowel function persisting for more than 4 days. Univariate analysis and multiple logistic regression models were performed to investigate risk factors, and stratified analysis was carried out to examine the primary association at different levels of a potential confounding factor.

RESULTS

A total of 162 patients composed of 63 patients undergoing laparotomy and 99 patients undergoing laparoscopy were enrolled and PPOI was observed in 32 (19.75%) patients. Risk factors significantly correlated with PPOI were as follows: open surgery, older age, late surgical pathologic staging, postoperative use of opioid analgesic, low level of postoperative albumin and serum potassium. Compared to open surgery, the laparoscopic surgery was a strong protective factor for PPOI after adjusting related variables (OR = 0.17, CI: 0.05-0.52, P = .002). There was an interaction between surgical methods and the postoperative WBC level (P for interaction = .007). In the two group stratified analysis of WBC, laparoscopic surgery had a significant lower risk of PPOI than open group for the patients with WBC counts above the middle level in crude or adjusted models. This result remained significantly in the three group stratified analysis for the patients with WBC counts in the middle and or high tertile groups.

CONCLUSIONS

PPOI is a common postoperative complication of patients after gastrectomy. Laparoscopic surgery is associated with decreased risk of PPOI in gastric surgery. Patients who underwent open surgery and presented with high level of WBC should be cautious with PPOI.

Validity of the I-FEED score for postoperative gastrointestinal function in patients undergoing colorectal surgery

BACKGROUND

Postoperative ileus (POI) is common after gastrointestinal surgery and is associated with significant morbidity and costs. However, POI is poorly defined. The I-FEED score is a novel outcome measure for POI, developed by expert consensus. It contains five elements (intake, response to nausea treatment, emesis, exam, and duration, each scored with 0, 1, or 3 points) and classifies patients into normal, postoperative gastrointestinal intolerance (POGI), and postoperative gastrointestinal dysfunction (POGD). However, it has not yet been validated in a clinical context. The objective was to provide validity evidence for the I-FEED score to measure the construct of POI in patients undergoing colorectal surgery.

METHODS

Data previously collected from a clinical trial investigating the impact of different perioperative fluid management strategies on primary POI in patients undergoing elective laparoscopic colectomy (2013-2015) were analyzed. Patients were managed by a longstanding Enhanced Recovery program (expected length of stay (LOS): 3 days). Daily I-FEED scores were generated (normal 0-2, POGI 3-5, POGD 6+ points) up to hospital discharge or postoperative day 7. Validity was assessed by testing the hypotheses that I-FEED score was higher (1) in patients with longer time to GI3 (tolerating diet + flatus/bowel movement), (2) with longer LOS (> 3 days vs shorter), (3) in patients with complications vs without, (4) in patients with poorer recovery (measured by Quality of Recovery-9 questionnaire).

RESULTS

A total of 128 patients were included for analysis (mean age 61.7 years (SD 15.2), 57% male, 71% malignancy, and 39.1% rectal resection). Median LOS was 4 days [IQR3-5], and 32% experienced postoperative in-hospital morbidity. Overall, 48% of patients were categorized as normal, 22% POGI, and 30% POGD. The data supported all 4 hypotheses.

CONCLUSIONS

This study contributes preliminary validity evidence for the I-FEED score as a measure for POI after colorectal surgery.

Prediction model and web-based risk calculator for postoperative ileus after loop ileostomy closure

Background

Postoperative ileus (POI) is a significant complication after loop ileostomy closure given both its frequency and impact on the patient. The purpose of this study was to develop and externally validate a prediction model for POI after loop ileostomy closure.

Methods

The model was developed and validated according to the TRIPOD checklist for prediction model development and validation. The development cohort included consecutive patients who underwent loop ileostomy closure in two teaching hospitals in Montreal, Canada. Candidate variables considered for inclusion in the model were chosen a priori based on subject knowledge. The final prediction model, which modelled the 30-day cumulative incidence of POI using logistic regression, was selected using the highest area under the receiver operating characteristic curve (AUC) criterion. Model calibration was assessed using the Hosmer–Lemeshow goodness-of-fit test. The model was then validated externally in an independent cohort of similar patients from the University of British Columbia.

Results

The development cohort included 531 patients, in whom the incidence of POI was 16·8 per cent. The final model included five variables: age, ASA fitness grade, underlying pathology/treatment, interval between ileostomy creation and closure, and duration of surgery for ileostomy closure (AUC 0·68, 95 per cent c.i. 0·61 to 0·74). The model demonstrated good calibration (P = 0·142). The validation cohort consisted of 216 patients, and the incidence of POI was 15·7 per cent. On external validation, the model maintained good discrimination (AUC 0·72, 0·63 to 0·81) and calibration (P = 0·538).

Conclusion

A prediction model was developed for POI after loop ileostomy closure and included five variables. The model maintained good performance on external validation.