Postoperative ileus: etiologies and interventions

Pathophysiology and Management of Postoperative Ileus in Adults and Neonates: A Review

Postoperative ileus (POI) is caused by enteric neural dysfunction and inflammatory response to the stress of surgery as well as the effect of anesthetics and opioid pain medications. POI results in prolonged hospital stays, increased medical costs, and diminished enteral nutrition, rendering it a problem worth tackling. Many cellular pathways are implicated in this disease process, creating numerous opportunities for targeted management strategies. There is a gap in the literature in studies exploring neonatal POI pathophysiology and treatment options. It is well known that neonatal immune and enteric nervous systems are immature, and this results in gut physiology which is distinct from adults. Neonates undergoing abdominal surgery face similar surgical stressors and exposure to medications that cause POI in adults. In this review, we aim to summarize the existing adult and neonatal literature on POI pathophysiology and management and explore applications in the neonatal population.

Effect evaluation of different preventive measures for ileus after abdominal operation: A systematic review and network meta-analysis

Background

Different approaches to the prevention of postoperative ileus have been evaluated in numerous randomized controlled trials. This network meta-analysis aimed to investigate the relative effectiveness of different interventions in preventing postoperative ileus.

Methods

Randomized controlled trials (RCTS) on the prevention of postoperative ileus were screened from Chinese and foreign medical databases and compared. STATA software was used for network meta-analysis using the frequency method. Random-effects network meta-analysis was also used to compare all schemes directly and indirectly.

Results

A total of 105 randomized controlled trials with 18,840 participants were included in this report. The results of the network meta-analysis showed that intravenous analgesia was most effective in preventing the incidence of postoperative ileus, the surface under the cumulative ranking curve (SUCRA) is 90.5. The most effective intervention for reducing the first postoperative exhaust time was postoperative abdominal mechanical massage (SUCRA: 97.3), and the most effective intervention for reducing the first postoperative defecation time was high-dose opioid antagonists (SUCRA: 84.3). Additionally, the most effective intervention for reducing the time to initiate a normal diet after surgery was accelerated rehabilitation (SUCRA: 85.4). A comprehensive analysis demonstrated the effectiveness and prominence of oral opioid antagonists and electroacupuncture (EA) combined with gum.

Conclusion

This network meta-analysis determined that oral opioid antagonists and EA combined with chewing gum are the most effective treatments and optimal interventions for reducing the incidence of postoperative ileus. However, methods such as abdominal mechanical massage and coffee require further high-quality research.

Enteric neuro-immune interactions in intestinal health and disease

The enteric nervous system is an autonomous neuronal circuit that regulates many processes far beyond the peristalsis in the gastro-intestinal tract. This circuit, consisting of enteric neurons and enteric glial cells, can engage in many intercellular interactions shaping the homeostatic microenvironment in the gut. Perhaps the most well documented interactions taking place, are the intestinal neuro-immune interactions which are essential for the fine-tuning of oral tolerance. In the context of intestinal disease, compelling evidence demonstrates both protective and detrimental roles for this bidirectional neuro-immune signaling. This review discusses the different immune cell types that are recognized to engage in neuronal crosstalk during intestinal health and disease. Highlighting the molecular pathways involved in the neuro-immune interactions might inspire novel strategies to target intestinal disease.

A history of bariatric surgery before surgery for colorectal cancer may improve short-term postoperative outcomes: Analysis of the national inpatient sample 2015-2019

BACKGROUND

Bariatric surgery is the most effective and sustainable form of weight loss. Bariatric surgery before elective operations for colorectal pathology may improve postoperative outcomes. To compare patients with and without prior bariatric surgery undergoing surgery for colorectal cancer in terms of postoperative morbidity and health care use.

METHODS

Adult patients undergoing resection for colorectal cancer from 2015 to 2019 were identified from the National Inpatient Sample. Patients were stratified according to their history of bariatric surgery. Propensity score matching with 4:1 nearest-neighbor matching was performed according to demographic, operative, and hospital characteristics. The primary outcome was postoperative morbidity. Secondary outcomes included system-specific postoperative complications, postoperative mortality, postoperative length of stay, total admission health care cost, and post-discharge disposition. McNemar's test and Wilcoxon matched-pairs signed-rank test were performed.

RESULTS

After propensity score matching, 1,197 patients without prior bariatric surgery and 376 patients with prior bariatric surgery were included. Patients with prior bariatric surgery had an absolute reduction of 6.5% in overall in-hospital postoperative morbidity (19.1% vs 25.6%, P < .0001), a $5,256 decrease in hospitalization cost ($70,344 vs $75,600, P = .034), and were more likely to be discharged home after their index operation (72.9% vs 63.9%, P < .0001).

CONCLUSION

Bariatric surgery before surgery for colorectal cancer may be associated with decreased postoperative morbidity and health care use. Bariatric surgery and other forms of rapid and effective weight loss, such as very low-energy diets, should be evaluated further for the optimization of obese patients before nonbariatric abdominal surgery.

Effects of Gum Chewing on Recovery From Postoperative Ileus: A Randomized Clinical Trail

BACKGROUND

Sham feeding with products such as chewing gum has been theorized to decrease the incidence and time to resolution of postoperative ileus. The conflicting findings in the literature on this subject are because in part of the use of mixed study populations, which has led to difficulties in assessing the value of sham feeding in ameliorating this condition.

PURPOSE

The aim of this study was to evaluate the efficacy of postsurgical gum chewing in restoring normal bowel movement in patients with colorectal cancer who had undergone abdominal surgery for colon resection.

METHODS

A randomized controlled trial was used to examine the time to first postoperative flatus and defecation. The intervention group ( n = 30) received xylitol chewing gum on the first day after colon resection, one piece of gum for 15 minutes, 3 times daily, until the time to first flatus and defecation. Both the intervention and control groups ( n = 30) received standard postoperative care and were encouraged to walk as soon as possible after surgery. The time to first flatus was reported by patients.

RESULTS

The time to first flatus and defecation in the intervention group was significantly shorter than that in the control group (39.13 ± 15.66 vs. 52.92 ± 21.97 hours and 54.55 ± 18.90 vs. 77.98 ± 34.59 hours, respectively). However, after controlling for age and surgical duration, only time to first flatus was significantly shorter in the intervention group. Significantly positive correlations were found between time to first flatus and time to first defecation in both groups.

CONCLUSIONS/IMPLICATIONS FOR PRACTICE

In this study, gum chewing was shown to have a positive effect on the time to first postoperative flatus and defecation. This inexpensive and noninvasive intervention may be recommended to decrease the time to resolution of postsurgical ileus in middle-aged and older patients who have undergone open abdominal surgery for colorectal resection.

Molecular and cellular mechanisms underlying postoperative paralytic ileus by various immune cell types

Postoperative ileus (POI) is a well-known complication following gut manipulation or surgical trauma, leading to an impaired gut motility and prolonged postoperative recovery time. Few current therapeutic strategies can prevent POI, and this disorder remains to be a major clinical challenge for patients undergoing surgery. Comprehensive understanding of cellular and molecular mechanisms related to the pathogenesis of POI stimulates the discovery of more promising targets for treatment. POI is closely associated with a series of inflammatory events within the bowel wall, and as key components of inflammatory mechanisms, different types of immune cells, including macrophages, dendritic cells, and T lymphocytes, play significant roles during the development of POI. A variety of immune cells are recruited into the manipulation sites after surgery, contributing to early inflammatory events or impaired gut motility. Our review intends to summarize the specific relationship between different immune cells and POI, mainly focusing on the relevant mechanisms underlying this disorder.

Clinical Importance, Incidence and Risk Factors for the Development of Postoperative Ileus Following Adult Spinal Deformity Surgery

STUDY DESIGN

Retrospective observational study of a cohort of consecutive patients.

OBJECTIVES

Postoperative ileus (POI) is associated with a variety of adverse effects. Although the incidence of and risk factors for POI following spinal surgery have been reported, the frequency and pathology of POI after spinal corrective surgery for adult spinal deformity (ASD) are still largely unknown. The study objectives were to: (1) clarify the prevalence and clinical significance of POI, (2) elucidate the risk factors for POI, (3) determine radiographically which preoperative and/or postoperative spinal parameters predominantly influence the risk of POI after spinal corrective surgery for ASD.

METHODS

We included data from 144 consecutive patients who underwent spinal corrective surgery. Perioperative medical complications and clinical information were extracted from patient electronic medical records. Preoperative radiographic parameters and changes in radiographic parameters after surgery were compared between patients with and without POI. Multivariate logistic regression analyses were performed to clarify potential risk factors for POI.

RESULTS

POI developed in 25/144 (17.4%) patients and was the most common complication in the present study. The frequencies of smoking, gastroesophageal reflux disease, and lateral lumbar interbody fusion (LLIF), as well as the duration of surgery were significantly greater in the group with POI versus the group without POI. Among radiographic parameters, only the change in thoracolumbar kyphosis (TLK) from before to after surgery was significantly larger in the group with POI. Multivariate logistic regression analysis showed that male sex, LLIF and large changes in TLK from before to after surgery were significantly associated with the development of POI.

CONCLUSIONS

These results suggested that LLIF and large corrections in TLK were independent risk factors for POI after ASD surgery. When patients with ASD have large TLK preoperatively, and it is determined that a large correction is needed, physicians must be aware of the potential for occurrence of POI.

Effect of anaesthetic depth on primary postoperative ileus after laparoscopic colorectal surgery: protocol for and preliminary data from a prospective, randomised, controlled trial

INTRODUCTION

Primary postoperative ileus is one of the principal factors affecting in-hospital recovery after colorectal surgery. Research on the relationship between anaesthetic depth and perioperative outcomes has been attracting growing attention. However, the impact of anaesthetic depth on the recovery of gastrointestinal function after surgery is unclear. We aimed to conduct a single-centre, prospective, randomised, controlled trial to explore the effect of anaesthetic depth on primary postoperative ileus after laparoscopic colorectal surgery.

METHODS AND ANALYSIS

In this single-centre, prospective, patient-blinded and assessor-blinded, parallel, randomised, controlled trial, a total of 854 American Society of Anesthesiologists physical status I-III patients, aged between 18 and 65 years and scheduled for laparoscopic colorectal surgery lasting ≥2 hours, will be randomly assigned to deep anaesthesia group (Bispectral Index (BIS) 30-40) or light anaesthesia group (BIS 45-55). The primary outcome is primary postoperative ileus during the hospital stay. Secondary outcomes were time to gastrointestinal function recovery, another defined postoperative ileus, 15-item quality of recovery score, length of postoperative stay, postoperative 30-day complications and serum concentrations of intestinal fatty acid-binding protein at 6 hours after surgery.

ETHICS AND DISSEMINATION

The protocol was approved by Medical Ethics Committee of Nanfang Hospital, Southern Medical University (Approval number: NFEC-2018-107) prior to recruitment. All participants will provide written informed consent before randomisation. Findings of the trial will be disseminated through peer-reviewed journals and scientific conferences.

TRIAL REGISTRATION NUMBER

ChiCTR1800018725.

Sympathetic Pathways Target Cholinergic Neurons in the Human Colonic Myenteric Plexus

Background

The sympathetic nervous system inhibits human colonic motility largely by effects on enteric neurons. Noradrenergic axons, which branch extensively in the myenteric plexus, are integral to this modulatory role, but whether they contact specific types of enteric neurons is unknown. The purpose of this study was to determine the association of noradrenergic varicosities with types of enteric neurons.

Methods

Human colonic tissue from seven patients was fixed and dissected prior to multi-layer immunohistochemistry for human RNA binding proteins C and D (HuC/D) (pan-neuronal cell body labelling), tyrosine hydroxylase (TH, catecholaminergic labelling), Enkephalin (ENK), choline acetyltransferase (ChAT, cholinergic labelling) and/or nitric oxide synthase (NOS, nitrergic labelling) and imaged using confocal microscopy. TH-immunoreactive varicose nerve endings and myenteric cell bodies were reconstructed as three dimensional digital images. Data was exported to a purpose-built software package which quantified the density of varicosities close to the surface of each myenteric cell body.

Results

TH-immunoreactive varicosities had a greater mean density within 1 μm of the surface of ChAT +/NOS− nerve cell bodies compared with ChAT−/NOS + cell bodies. Similarly, ENK-immunoreactive varicosities also had a greater mean density close to ChAT +/NOS− cell bodies compared with ChAT−/NOS + cells.

Conclusion

A method for quantifying close associations between varicosities and nerve cell bodies was developed. Sympathetic axons in the myenteric plexus preferentially target cholinergic excitatory cells compared to nitrergic neurons (which are largely inhibitory). This connectivity is likely to be involved in inhibitory modulation of human colonic motility by the sympathetic nervous system.

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.

Exposing the incidence of ileus in pelvic and acetabular fractures: a retrospective case analysis

BACKGROUND

Paralytic ileus is a temporary inhibition of gastrointestinal mobility in the absence of mechanical obstruction. Ileus has previously been observed in up to 40% of patients undergoing bowel surgery, leading to increased morbidity and length of stay. Pelvic and acetabular fractures are often caused by high energy trauma and are associated with a risk of visceral injury.  Prior to this study, there were no reported figures for the incidence of ileus in patients presenting with pelvic and/or acetabular fractures.

METHODS

All patients over the age of 16 presenting to a major trauma centre throughout 2019 were included. Data collected included patient demographics, injury pattern, fracture management and presence of ileus. As in previous studies, patients were identified as having ileus if they failed to tolerate an oral diet and open their bowels for more than three days (GI-2). Analysis assessed risk factors for ileus as well as its effect on length of stay.

RESULTS

An incidence of ileus of 40.35% was observed in the 57 included patients. Across all patients, ileus was three times more common in patients with a diagnosis of diabetes mellitus (p= 0.56) and 2.5 times more common in the presence of an open pelvic/ acetabular fracture (p= 0.73). Length of stay was significantly longer in patients under 65 years identified as having ileus (p= 0.046). Gender, age, opiate use, fracture management and surgical approach were not identified as risk factors for ileus.

CONCLUSION/ FINDINGS

This is the first study to report the incidence of and risk factors for ileus following admission with pelvic and/or acetabular fractures. Due to the morbidity and cost associated with this condition, further research is required to assess the effect of interventions to reduce its incidence in this patient subgroup.

OUP accepted manuscript

Background

Methods

Results

Conclusions

Development of an Enhanced Recovery Program in Pediatric, Adolescent, and Young Adult Surgical Oncology Patients

Enhanced recovery after surgery (ERAS) protocols are standardized perioperative treatment plans aimed at improving recovery time in patients following surgery using a multidisciplinary team approach. These protocols have been shown to optimize pain control, improve mobility, and decrease postoperative ileus and other surgical complications, thereby leading to a reduction in length of stay and readmission rates. To date, no ERAS-based protocols have been developed specifically for pediatric patients undergoing oncologic surgery. Our objective is to describe the development of a novel protocol for pediatric, adolescent, and young adult surgical oncology patients. Our protocol includes the following components: preoperative counseling, optimization of nutrition status, minimization of opioids, meticulous titration of fluids, and early mobilization. We describe the planning and implementation challenges and the successes of our protocol. The effectiveness of our program in improving perioperative outcomes in this surgical population could lead to the adaptation of such protocols for similar populations at other centers and would lend support to the use of ERAS in the pediatric population overall.

Enhanced Recovery after Surgery Protocol Accelerates Recovery of Lumbar Disc Herniation among Elderly Patients Undergoing Discectomy via Promoting Gastrointestinal Function

This study aimed to analyze the effect of the enhanced recovery after surgery (ERAS) protocol on the recovery of gastrointestinal function in patients with lumbar disc herniation after discectomy. A total of 179 patients with lumbar disc herniation were randomly divided into the ERAS and non-ERAS groups. The non-ERAS group received routine nursing, and the ERAS group received ERAS strategy. The two groups were compared for general recovery indicators such as postoperative hemoglobin and prealbumin, satisfaction, and length of hospital stay. Gastrointestinal function was also evaluated, such as postoperative feeding time, intestinal chirping recovery time, intestinal exhaust gas recovery time, and complications such as ileus, nausea, and vomiting. The satisfaction of patients in the ERAS group (86.15 ± 2.43) was significantly higher than that in the non-ERAS group (77.19 ± 3.32), and the difference was statistically significant (P < 0.05). The average time of eating in the ERAS group was 2.27 h after surgery. In addition, the amount of eating in the ERAS group was significantly better than that in the non-ERAS group, and the difference was statistically significant. In the ERAS group, intestinal chirping recovery time recovered to normal time, and exhaust recovery time and average defecation time were significantly shorter than those in the non-ERAS group. In the ERAS group, the average amount of hemoglobin and prealbumin decreased 3 days after operation, which was significantly lower than that in the non-ERAS group. To sum up, ERAS has an evident effect on the recovery of gastrointestinal function after discectomy of disc herniation, which can promote the recovery of patients.

Bowel dysfunction after elective spinal surgery: etiology, diagnostics and management based on the medical literature and experience in a university hospital

BACKGROUND

Bowel dysfunction after spinal surgery is often underestimated and if not treated in a timely manner can lead to undesirable surgical interventions or fatal complications. The current medical literature primarily focuses on bowel dysfunction as a result of spinal injury.

OBJECTIVE

The purpose of this review is to explore this topic in evaluating current evidence regarding the causes of acute bowel dysfunction after elective spinal surgery, primarily the thoracolumbar spine. Since available evidence for recommendations of treatment is scarce, an interdisciplinary management approach for treatment of bowel dysfunction following spinal surgery is also formulated.

MATERIAL AND METHODS

An extensive literature search was carried out on PubMed. Keywords that were used in the search included bowel dysfunction, obstruction, postoperative ileus, spinal surgery, spinal fusion, constipation, opioid-induced constipation, colonic pseudo-obstruction, ischemic colitis, immobility-induced bowel changes, epidural anesthesia and diet. Relevant studies were chosen and included in the review. The treatment approach used in the spine center of a university hospital was included.

RESULTS

Current research mainly focuses on investigating the nature and symptomatology of chronic bowel dysfunction after spinal cord injury. Emphasis on the acute phase of bowel dysfunction in patients after elective spinal surgery is lacking. The comorbidities that exacerbate bowel dysfunction postoperatively are well-defined. There has been refinement and expansion of the pharmacological and nonpharmacological treatment that could be implemented. Enough evidence exists to provide sufficient care.

CONCLUSION

Management of acute bowel dysfunction after spinal surgery requires a comprehensive and individualized approach, encompassing comorbidities, behavioral changes, medications and surgery. Close supervision and timely treatment could minimize further complications. Research is required to identify patients who are at a higher risk of developing bowel dysfunction after specific spinal procedures.

Postoperative ileus-An ongoing conundrum

BACKGROUND

Postoperative ileus is common and is a major clinical problem. It has been widely studied in patients and in experimental models in laboratory animals. A wide variety of treatments have been tested to prevent or modify the course of this disorder.

PURPOSE

This review draws together information on animal studies of ileus with studies on human patients. It summarizes some of the conceptual advances made in understanding the mechanisms that underlie paralytic ileus. The treatments that have been tested in human subjects (both pharmacological and non-pharmacological) and their efficacy are summarized and graded consistent with current clinical guidelines. The review is not intended to provide a comprehensive overview of ileus, but rather a general understanding of the major clinical problems associated with it, how animal models have been useful to elucidate key mechanisms and, finally, some perspectives from both scientists and clinicians as to how we may move forward with this debilitating yet common condition.

Risk factors for postoperative ileus after oblique lateral interbody fusion: a multivariate analysis

BACKGROUND CONTEXT

Oblique lateral interbody fusion (OLIF)-has become a widely used, efficient surgical tool for various degenerative lumbar conditions. Postoperative ileus (POI) is a relatively common complication after anterior lumbar interbody fusion due to the manipulation of the intestine during the surgical approach. However, to our knowledge, little is known about POI following OLIF even though it also involves bowel manipulation during a surgical procedure.

PURPOSE

To assess the incidence of POI and identify independent risk factors for POI development after OLIF.

STUDY DESIGN/SETTING

Retrospective cohort study.

PATIENT SAMPLE

All consecutive patients who underwent OLIF and percutaneous pedicle screw instrumentation from August 2012 until October 2019 at a single institution OUTCOME MEASURES: Patient demographics (sex, age, body weight, height, and body mass index), comorbidities (diabetes mellitus, gastroesophageal reflux disease, antithrombotic medication, previous abdominal surgery, and previous lumbar surgery), and perioperative details (preoperative diagnosis, number of levels fused, inadvertent endplate fracture during cage insertion, type of interbody graft, intraoperative estimated blood loss, duration of surgery and anesthesia, the amount of intraoperative remifentanil and propofol used as anesthetic agents, the total postoperative retroperitoneal closed-suction drainage output, and the cumulative opioid dosage administered in the first 72 hours postoperatively).

METHODS

POI was defined as 2 or more of the following at 72 hours postoperatively: (1) ongoing nausea or vomiting postoperatively, (2) the absence of flatus over last 24-hour period, (3) inability to tolerate an oral diet over last 24-hour period, (4) ongoing abdominal distention postoperatively, and (5) radiological confirmation. The subjects were divided into 2 groups: patients with POI and those without POI. Binary logistic regression analyses were performed on demographics, comorbidities, and perioperative factors to identify independent risk factors for POI.

RESULTS

Eighteen (3.9%) of 460 patients experienced POI after OLIF and percutaneous pedicle screw instrumentation. Patients with POI had a significantly longer postoperative length of hospital stay than those without POI (8.61 ± 2.66 vs 6.48 ± 2.64, p = .001). Multivariate logistic regression analysis identified inadvertent endplate fracture (adjusted odds ratio = 6.017, p = .001) and the amount of intraoperative remifentanil (adjusted odds ratio = 1.057, p = .024) as independent risk factors for the occurrence of POI following OLIF.

CONCLUSION

This study identified inadvertent endplate fracture and the amount of intraoperative remifentanil as independent risk factors for the development of POI after OLIF.

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.

Incidence and Risk Factors of Gastrointestinal and Hepatobiliary Complications after Spinal Fusion Surgery: a Retrospective Cohort Study

BACKGROUND

Spinal surgery holds a higher chance of unpredicted postoperative medical complications among orthopedic surgeries. Several studies have analyzed the risk factors for diverse postoperative medical complications, but the majority investigated incidences of each complication qualitatively. Among gastrointestinal complications, reports regarding postoperative ileus were relatively frequent. However, risk factors or incidences of hepatobiliary complications have yet to be investigated. The purpose of this study was to examine the incidence of gastrointestinal complications after spinal surgery, quantitatively analyze the risk factors of frequent complications, and to determine cues requiring early approaches.

METHODS

In total, 234 consecutive patients who underwent spinal fusion surgery performed by one senior doctor at our institute in one-year period were retrospectively enrolled for analyses. The primary outcomes were presence of paralytic ileus, elevated serum alanine transaminase (ALT) and aspartate transaminase (AST) levels, and elevated total bilirubin levels. Univariate logistic regression analyses of all variables were performed. In turn, significant results were reanalyzed by multivariate logistic regression. The variables used were adjusted with age and gender.

RESULTS

Gastrointestinal complications were observed in 15.8% of patients. Upon the risk factors of postoperative ileus, duration of anesthesia (odds ratio [OR], 1.373; P = 0.015), number of fused segments (OR, 1.202; P = 0.047), and hepatobiliary diseases (OR, 2.976; P = 0.029) were significantly different. For elevated liver enzymes, men (OR, 2.717; P = 0.003), number of fused segments (OR, 1.234; P = 0.033), and underlying hepatobiliary (OR, 2.704; P = 0.031) and rheumatoid diseases (OR, 5.021; P = 0.012) had significantly different results. Lastly, risk factors for total bilirubin elevation were: duration of anesthesia (OR, 1.431; P = 0.008), number of fused segments (OR, 1.359; P = 0.001), underlying hepatobiliary diseases (OR, 3.426; P = 0.014), and thoracolumbar junction involving fusions (OR, 4.134; P = 0.002) compared to lumbar spine limited fusions.

CONCLUSION

Patients on postoperative care after spinal surgery should receive direct attention as soon as possible after manifesting abdominal symptoms. Laboratory and radiologic results must be carefully reviewed, and early consultation to gastroenterologists or general surgeons is recommended to avoid preventable complications.

Effects of electroacupuncture on the intestinal motility and local inflammation are modulated by acupoint selection and stimulation frequency in postoperative ileus mice

BACKGROUND

Electroacupuncture (EA) is widely used in various gastrointestinal diseases around the world, including POI. Here, we investigated different therapeutic effects of EA using lower limb and abdomen acupoints.

METHODS

Intestinal manipulation was performed in 88 mice, and eight mice underwent a sham operation. Forty mice were randomly divided into model group and four EA groups receiving stimulation at ST36 (2, 10, 30, 100 Hz). The most effective frequency was then used in the following experiments. Forty-eight mice were randomly divided into six groups receiving EA treatment at ST37, ST39, ST25, CV4, CV12, and a non-acupuncture point. Gastrointestinal motility and plasma TNF-α, IL-6 were evaluated in all mice. The local immune response and α-smooth muscle actin (α-SMA) expression were assessed by immunofluorescence, ELISA, and HE staining.

RESULTS

ST36 stimulated with 10 or 30 Hz EA significantly increased the gastrointestinal motility and attenuated peripheral inflammation; however, ST36 stimulated with 2 or 100 Hz did not induce any effect. The therapeutic effects on motility and inflammation of 10 Hz EA in the ST36 group were similar in the ST36, ST37, ST39, or CV4 groups, but when applied to ST25, CV12 or non-acupoint had no significant differences. EA at ST36, ST37, ST39, or CV4 significantly inhibited local MPO activity, immune cells infiltration, and increased α-SMA.

CONCLUSIONS

EA at lower limb and abdomen acupoints with the same stimulation parameters had different therapeutic effects on postoperative dysmotility and inflammation. Furthermore, EA protected SMC to improve gastrointestinal transit by reducing local inflammation in the intestinal musculature in POI.

Short-term Outcomes of Elective 2-Stage Restorative Proctocolectomy for Ulcerative Colitis in Korea: Does Laparoscopy Have Benefits?

Purpose

This study aimed to compare the short-term outcomes of the open and laparoscopic approaches to 2-stage restorative proctocolectomy (RPC) for Korean patients with ulcerative colitis (UC).

Methods

We retrospectively analyzed the medical records of 73 patients with UC who underwent elective RPC between 2009 and 2016. Patient characteristics, operative details, and postoperative complications within 30 days were compared between the open and laparoscopic groups.

Results

There were 26 cases (36%) in the laparoscopic group, which had a lower mean body mass index (P = 0.025), faster mean time to recovery of bowel function (P = 0.004), less intraoperative blood loss (P = 0.004), and less pain on the first and seventh postoperative days (P = 0.029 and P = 0.027, respectively) compared to open group. There were no deaths, and the overall complication rate was 43.8%. There was no between-group difference in the overall complication rate; however, postoperative ileus was more frequent in the open group (27.7% vs. 7.7%, P = 0.043). Current smoking (odds ratio [OR], 44.4; P = 0.003) and open surgery (OR, 5.4; P = 0.014) were the independent risk factors for postoperative complications after RPC.

Conclusion

Laparoscopic RPC was associated with acceptable morbidity and faster recovery than the open approach. The laparoscopic approach is a feasible and safe option for surgical treatment for UC in selective cases.

Retrospective evaluation of risk factors and treatment outcome predictors in cats presenting to the emergency room for constipation

OBJECTIVES

Constipation is a common complaint in cats presenting to the emergency room and can become a frustrating recurrent condition. Despite widespread anecdotal reports of risk factors for constipation, at the time of writing there have been no studies supporting these associations or assessing treatment outcomes. The aim of this study was to identify risk factors in the signalment, history, physical examination and clinicopathologic findings of cats presenting to the emergency room for constipation. In addition, we aimed to assess factors contributing to the success or failure of enemas administered to these cats.

METHODS

A medical record search identified 189 cats with a diagnosis of constipation/obstipation that were treated and discharged by the emergency service at an academic veterinary hospital. Data regarding signalment, medical history, physical examination and clinicopathologic findings, as well as treatments performed, were recorded. Ninety-nine cats presenting to the emergency room for other reasons were identified as controls. Statistical analysis was performed to assess risk factors for constipation, as well as success/failure of enema treatments.

RESULTS

Older, overweight cats and cats with chronic kidney disease or previous episodes of constipation were found to be at increased risk of constipation (P <0.0001, P = 0.0004, P = 0.0046 and P <0.0001, respectively). Ionized calcium levels were significantly higher in constipated cats, though varied significantly within the cohort (P = 0.0133). Cats noted to be painful on abdominal palpation were less likely to defecate following an enema. Adjunctive treatments (fluids, laxatives) increased the likelihood of a successful enema but were not statistically significant.

CONCLUSIONS AND RELEVANCE

Older, overweight cats with a history of constipation or chronic kidney disease are more likely to present for constipation. Further studies are needed to determine the most appropriate treatment protocol in an urgent care setting.

The Use of Coffee to Decrease the Incidence of Postoperative Ileus: A Systematic Review and Meta-Analysis

PURPOSE

To investigate the efficacy of providing coffee to elective abdominal surgery patients, immediately postoperatively, to lessen postoperative ileus.

DESIGN

A systematic review with meta-analysis of six randomized controlled trials published since 2012.

METHODS

Methodological quality was evaluated using the Cochrane guidelines. The Grading of Recommendations, Assessment, Development, and Evaluations assessment tool evaluated the quality of the evidence. Subgroup analyses were completed if the I² statistic demonstrated heterogeneity (greater than 50%).

FINDINGS

Coffee was statistically significant in shortening the time between surgery and the first passage of stool (mean difference, -9.38; 95% confidence interval, -17.60 to -1.16; P = .03). Although not statistically significant (P = .20), the overall effect favored shorter hospital stays for those patients receiving coffee.

CONCLUSIONS

The current systematic review and meta-analysis suggests that coffee given as early as 2 hours postoperatively decreases time to first bowel movement. In addition, patients tolerated solid food faster and were discharged sooner when given coffee immediately postoperatively.

Postoperative paralytic ileus after cytoreductive surgery combined with heated intraperitoneal chemotherapy

Background

Patients with peritoneal malignancy treated by cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) are prone to develop postoperative paralytic ileus (POI). POI is associated with significant increase in both morbidity and mortality. CRS and HIPEC commonly result in prolonged POI (PPOI). The objective was to clarify the extent of PPOI in patients treated by CRS and HIPEC for peritoneal malignancy.

Methods

This was a prospective multicenter study including patients operated with CRS and HIPEC at the Department of Surgery, Aarhus University Hospital, Denmark and the Peritoneal Malignancy Institute, Basingstoke, United Kingdom. A total of 85 patients were included over 5 months. Patients prospectively reported parameters of postoperative gastrointestinal function in a diary from post-operative day 1 (POD1) until discharge. PPOI was defined as first defecation on POD6 or later.

Results

Median time to first flatus passage was 4 days (range 1–12). Median time to first defecation was 6 days (1–14). Median time to removal of nasojejunal tube was 4 days (3–13) and 7 days (1–43) for nasogastric tube. Forty-six patients (54%) developed PPOI. Patients with PPOI had longer time to first flatus (p<0.0001) and longer time to removal of nasojejunal tube (p=0.001). Duration of surgery correlated to time to first flatus (p=0.015) and time to removal of nasogastric or nasojejunal tube (p<0.0001) but not to time to first defecation (p=0.321).

Conclusions

Postoperative gastrointestinal paralysis remains a common and serious problem in patients treated with CRS and HIPEC.

Impact of Combination of Local Anesthetic Wounds Infiltration and Ultrasound Transversus Abdominal Plane Block in Patients Undergoing Robot-Assisted Radical Prostatectomy: Perioperative Results of a Double-Blind Randomized Controlled Trial

OBJECTIVE

To determinate benefits of the combination of local anesthetic wounds infiltration and ultrasound transversus abdominal plane (US-TAP) block with ropivacaine on postoperative pain, early recovery, and hospital stay in patients undergoing robot-assisted radical prostatectomy (RARP).

METHODS

The study is double-blinded randomized controlled trial. Our hypothesis was that the combination of wound infiltration and US-TAP block with ropivacaine would decrease immediate postoperative pain and opioids use. Primary outcomes included postoperative pain and opioids demand during the hospital stay. Secondary outcomes were nausea/vomiting rate, stool passing time, use of prokinetics, length of hospital stay (LOS), and 30-days readmission to the hospital for pain or other US-TAP block-related complications.

RESULTS

A total of 100 patients who underwent RARP were eligible for the analysis; 57 received the US-TAP block with 20 mL of 0.35% ropivacaine (US-TAP block group) and 43 did not receive US-TAP block (no-US-TAP group). All the patients received the local wound anesthetic infiltration with 20 mL of 0.35% ropivacaine. US-TAP block group showed a decreased mean Numerical Rating Scale (NRS) within 12 hours after surgery (1.6 vs 2.6; p = 0.02) and mean NRS (1.8 vs 2.7; p = 0.04) with lesser number of patients who used opioid (3.5% vs 18.6%; p = 0.01) during the first 24 hours. Moreover, we found a shorter mean LOS (4.27 vs 4.72, days; p = 0.04) with a lower requirement of prokinetics administration during the hospital stay (21% vs 72%; p < 0.001). No US-TAP block-related complications were reported.

CONCLUSION

Combination of anesthetic wound infiltration and US-TAP block with ropivacaine as part of a multimodal analgesic regimen can be safely offered to patients undergoing RARP and extended pelvic lymph node dissection. It improves the immediate postoperative pain control, reducing opioids administration and is associated to a decreased use of prokinetics and shorter hospital stay.

Gastrointestinal effects following acupuncture at Pericardium-6 and Stomach-36 in healthy dogs: a pilot study

OBJECTIVES

To quantify changes in gastric and intestinal emptying times in the conscious dog following gastrointestinal acupoint stimulation.

MATERIALS AND METHODS

In a randomised, blinded crossover study, six dogs were fed 30×1.5 mm barium-impregnated polyethylene spheres and underwent: (1) no acupuncture (Control); (2) stimulation of target points PC6 and ST36 (Target) and (3) stimulation of non-target points LU7 and BL55 (Sham). Abdominal radiographs were assessed immediately after feeding the spheres and every hour for 12 hours and their number in the stomach and large intestines was counted.

RESULTS

The number of barium-impregnated polyethylene spheres found distal to the stomach was less in the Target group compared to the Control and Sham groups between hours 2 and 4, but no differences between groups were seen for the remainder of the treatment period. The number of spheres found within the colon/rectum was less in the Target group compared to the Control and Sham groups between hours 4 and 6, and compared to the Sham group only at hour 7 but no differences between groups were seen after hour 8.

CLINICAL SIGNIFICANCE

Acupuncture targeted at the gastrointestinal tract of dogs was associated briefly with slowed gastric emptying and gastrointestinal transit time. This foundational study lays the groundwork for additional studies of acupuncture effects associated with altered physiologic states.

Efficacy of three different regimens in recovery of bowel function following elective cesarean section: a randomized trial

Aim:

To compare the efficacy of three postoperative feeding regimens on bowel function recovery after term elective cesarean section (CS).

Methods:

Women recruited for this randomized trial were allocated into three groups. Women in group (A) were instructed to chew sugarless gum for 10 min every 2 h after surgery. Group (B) mothers received IV fluids for 6 h followed by sipping fruit juices sweetened with honey. Group (C) had oral intake of clear fluids after passage of flatus and regular diet with the passage of bowel movement. The main outcome measures were the timing of first return to bowel movement and initiation of regular diet.

Results:

The mean times to first hearing of bowel sounds, to first flatus passage and to first defecation were significantly lower in group A (10, 17.5 and 28.1 h, respectively) compared to groups B and C [15.1, 24.9 and 36 h (B) and 21.6, 38.8 and 49.4 h (C)]. Initiation of regular diet was significantly earlier in group A compared to groups B and C (21 vs. 27.5 and 40.3 h, respectively).

Conclusion:

Chewing gum appears to be more advantageous than early or traditional feeding regimens after term elective CS resulting in rapid recovery of bowel function.

Effect of Yikou-Sizi powder hot compress on gastrointestinal functional recovery in patients after abdominal surgery: Study protocol for a randomized controlled trial

BACKGROUND

Postoperative gastrointestinal dysfunction (PGD) is a common complication of patients who have undergone surgery. The clinical manifestations cause great discomfort to postoperative patients and can severely affect postoperative recovery. However, although various pharmacologic agents have been explored for several years, success has been limited. Because some commonly used drugs have caused adverse reactions and because abdominal surgery patients generally cannot consume food or medication during the perioperative period, we were prompted to try an external Chinese medicine treatment method. Yikou-Sizi powder hot compress is an efficient therapy in our hospital, but there is a lack of rigorous studies to certify the safety and effectiveness of its external use to improve gastrointestinal motility. This study aimed to introduce the clinical trial design and test the ability of Yikou-Sizi powder hot compress treatment to accelerate gastrointestinal functional recovery after abdominal surgery.

METHODS

This study is a randomized controlled clinical trial. The participants will undergo laparoscopic colorectal cancer surgery and laparoscopic total hysterectomy. The primary outcome measure will be the gastrointestinal functional evaluation index, including the time to first passage of flatus, first defecation, first normal bowel sounds, and first consumption of liquid/semigeneral diet foods. According to good clinical practice (GCP), we will evaluate the clinical efficacy and safety of Yikou-Sizi powder hot compress and objectively study the acting mechanism of ghrelin. This pilot trial will be a standard, scientific, and clinical study designed to evaluate the effect of Yikou-Sizi powder hot compress for the recovery of gastrointestinal function after surgery and determine its overall safety.

DISCUSSION

This is the first study to describe the use of Yikou-Sizi powder hot compress to accelerate the recovery of gastrointestinal function after abdominal surgery. The study is designed as a randomized, controlled, clinical, large sample size and pilot trial. Evaluation will consist of combining the primary outcome measures with secondary outcome measures to ensure the objectivity and scientific validity of the study. Due to the observational design and the limited follow-up period, it is not possible to evaluate to what extent the connection between the observed improvement and the interventions represents a causal relationship. Efficient comparison between groups will be analyzed by chi-square test.

Opportunities and Challenges for Single-Unit Recordings from Enteric Neurons in Awake Animals

Advanced electrode designs have made single-unit neural recordings commonplace in modern neuroscience research. However, single-unit resolution remains out of reach for the intrinsic neurons of the gastrointestinal system. Single-unit recordings of the enteric (gut) nervous system have been conducted in anesthetized animal models and excised tissue, but there is a large physiological gap between awake and anesthetized animals, particularly for the enteric nervous system. Here, we describe the opportunity for advancing enteric neuroscience offered by single-unit recording capabilities in awake animals. We highlight the primary challenges to microelectrodes in the gastrointestinal system including structural, physiological, and signal quality challenges, and we provide design criteria recommendations for enteric microelectrodes.

Osteopathic Manipulative Treatment in Surgical Care: Short Review of Research Publications in Osteopathic Journals During the Period 1990 to 2017

Background.

A growing trend in surgical care is the investigation and incorporation of multimodal interventions into standardized programs. Additionally, manual therapies such as osteopathic manipulative treatment (OMT) are being used with patients in surgical care. Yet the scientific dialogue and the use of OMT in surgical care are currently insubstantial.

Objective.

The aim of this study was to present an overview of published research articles within the subject field of OMT in surgical care.

Method.

Summative review of peer-reviewed research articles published in osteopathic journals during the period 1990 to 2017. In total, 10 articles were identified.

Result.

Previous research has been conducted within the areas of abdominal, thoracic, gynecological, and/or orthopedic surgery with measured outcomes such as pain, analgesia consumption, length of hospital stay, and range of motion. Heterogeneity was identified in usage of osteopathic techniques, treatment duration, and occurrence, as well as in the treating osteopath’s experience.

Conclusion.

Despite the small number of research articles within this field, both positive measured effects as well as the absence of such effects were identified. Overall, there was a heterogeneity concerning surgical contexts, diagnoses, signs and symptoms, as well as surgical phases in current interprofessional osteopathic publications. In this era of multimodal surgical care, we argue that there is an urgent need to evaluate OMT in this context of care and with a proper research approach.

Daikenchuto for reducing postoperative ileus in patients undergoing elective abdominal surgery

BACKGROUND

Postoperative ileus is a major complication for persons undergoing abdominal surgery. Daikenchuto, a Japanese traditional medicine (Kampo), is a drug that may reduce postoperative ileus.

OBJECTIVES

To assess the efficacy and safety of Daikenchuto for reducing prolonged postoperative ileus in persons undergoing elective abdominal surgery.

SEARCH METHODS

We searched the following databases on 3 July 2017: CENTRAL, MEDLINE, Embase, ICHUSHI, WHO (World Health Organization) International Clinical Trials Registry Platform (ICTRP), EU Crinical Trials registry (EU-CTR), UMIN Clinical Trials Registry (UMIN-CTR), ClinicalTrials.gov, The Japan Society for Oriental Medicine (JSOM), American Society of Clinical Oncology (ASCO), Society of American Gastrointestinal and Endscopic Surgeons (SAGES). We set no limitations on language or date of publication.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing Daikenchuto with any control condition in adults, 18 years of age or older, undergoing elective abdominal surgery.

DATA COLLECTION AND ANALYSIS

We applied standard methodological procedures expected by Cochrane. Two review authors independently reviewed the articles identified by literature searches, extracted data, and assessed risk of bias of the included studies using the Cochrane software Review Manager 5.

MAIN RESULTS

We included seven RCTs with a total of 1202 participants. Overall, we judged the risk of bias as low in four studies and high in three studies. We are uncertain whether Daikenchuto reduced time to first flatus (mean difference (MD) -11.32 hours, 95% confidence interval (CI) -17.45 to -5.19; two RCTs, 83 participants; very low-quality evidence), or time to first bowel movement (MD -9.44 hours, 95% CI -22.22 to 3.35; four RCTs, 500 participants; very low-quality evidence) following surgery. There was little or no difference in time to resumption of regular solid food following surgery (MD 3.64 hours, 95% CI -24.45 to 31.74; two RCTs, 258 participants; low-quality evidence). There were no adverse events in either arm of the five RCTs that reported on drug-related adverse events (risk difference (RD) 0.00, 95% CI -0.02 to 0.02, 568 participants, low-quality evidence). We are uncertain of the effect of Daikenchuto on patient satisfaction (MD 0.09, 95% CI -0.19 to 0.37; one RCT, 81 participants; very low-quality of evidence). There was little or no difference in the incidence of any re-interventions for postoperative ileus before leaving hospital (risk ratio (RR) 0.99, 95% CI 0.06 to 15.62; one RCT, 207 participants; moderate-quality evidence), or length of hospital stay (MD -0.49 days, 95% CI -1.21 to 0.22; three RCTs, 292 participants; low-quality evidence).

AUTHORS' CONCLUSIONS

Evidence from current literature was unclear whether Daikenchuto reduced postoperative ileus in patients undergoing elective abdominal surgery, due to the small number of participants in the meta-analyses. Very low-quality evidence means we are uncertain whether Daikenchuto improved postoperative flatus or bowel movement. Further well-designed and adequately powered studies are needed to assess the efficacy of Daikenchuto.

Application of Pyridostigmine in Pediatric Gastrointestinal Motility Disorders: A Case Series

BACKGROUND

Gastrointestinal (GI) motility disorders are common in children. Treatment is challenging with limited medical and surgical options. Pyridostigmine, an acetyl cholinesterase inhibitor, increases acetylcholine at the neuromuscular junction promoting intestinal contractions. Little is known about the role and dosing of pyridostigmine in pediatric GI motility disorders.

METHODS

We present a case series of children with GI dysmotility managed with oral pyridostigmine. Patients' diagnoses include chronic intestinal pseudo-obstruction, gastroparesis with delayed small bowel transit, chronic constipation with failure to thrive, and prolonged ileus after pelvic surgery with chronic opioid use.

RESULTS

Pyridostigmine was effective and safe in all cases. Pyridostigmine decreased abdominal distention, increased bowel movement frequency, and improved enteral feeding tolerance. Effective dosing ranged between 0.25-2.0 mg/kg/day. One patient experienced cramping abdominal pain while on pyridostigmine, but pain resolved after medication was discontinued.

CONCLUSION

We found oral pyridostigmine to be helpful in children with different GI motility problems. Pyridostigmine should be considered in such patients when other treatment interventions have not been beneficial.

Pre-surgical Administration of Microbial Cell Preparation in Colorectal Cancer Patients: A Randomized Controlled Trial

INTRODUCTION

Disruption of normal gut function is a common side effect post abdominal surgery. It may result in reduced tolerance to oral nutrition and progress to postoperative ileus. Microbial cell preparation is beneficial as a pre-surgical nutritional supplement to aid in bowel recovery and promote the return of normal gut function following abdominal surgery. The aim of this study was to evaluate the efficacy of pre-surgical administration of microbial cell preparation in promoting the return of normal gut function.

METHOD

The study is a randomized, double-blind, placebo-controlled trial. In total, 40 patients were recruited. Patients were randomized to receive either microbial cell preparation (n = 20) or placebo (n = 20) for 7 days prior to elective surgery. The primary end point was the time to return of normal gut function, while the secondary end point was the duration of hospital stay.

RESULTS

The treatment group demonstrated significantly faster return of normal gut function with a median of 108.5 h (80-250 h) which was 48 h earlier than the placebo group at a median of 156.5 h (94-220 h), p = 0.022. The duration of hospital stay in the treatment group was also shorter at a median of 6.5 days (4-30 days), in comparison to the placebo group at 13 days (5-25 days), p = 0.012.

CONCLUSION

Pre-surgical administration of microbial cell preparation promotes the return of normal gut function in patients after colorectal cancer surgery, thus associated with faster recovery and shorter duration of hospital stay.

Nicotine chewing gum for the prevention of postoperative ileus after colorectal surgery: a multicenter, double-blind, randomised, controlled pilot study

PURPOSE

When postoperative ileus is not resolved after 5 days or recurs after resolution, prolonged POI (PPOI) is diagnosed. PPOI increases discomfort, morbidity and hospitalisation length, and is mainly caused by an inflammatory response following intestinal manipulation. This response can be weakened by targeting the cholinergic anti-inflammatory pathway, with nicotine as essential regulator. Chewing gum, already known to stimulate gastrointestinal motility itself, combined with nicotine is hypothesised to improve gastrointestinal recovery and prevent PPOI. This pilot study is the first to assess efficacy and safety of nicotine gum in colorectal surgery.

METHODS

Patients undergoing elective oncological colorectal surgery were enrolled in this double-blind, parallel-group, controlled trial and randomly assigned to a treatment protocol with normal or nicotine gum (2 mg). Patient reported outcomes (PROMS), clinical characteristics and blood samples were collected. Primary endpoint was defined as time to first passage of faeces and toleration of solid food for at least 24 h.

RESULTS

In total, 40 patients were enrolled (20 vs. 20). In both groups, six patients developed PPOI. Time to primary endpoint (4.50 [3.00-7.25] vs. 3.50 days [3.00-4.25], p = 0.398) and length of stay (5.50 [4.00-8.50] vs. 4.50 days [4.00-6.00], p = 0.738) did not differ significantly between normal and nicotine gum. There were no differences in PROMS, inflammatory parameters and postoperative complications.

CONCLUSIONS

We proved nicotine gum to be safe but ineffective in improving gastrointestinal recovery and prevention of PPOI after colorectal surgery. Other dosages and administration routes of nicotine should be tested in future research.

Alvimopan in the setting of colorectal resection with an ostomy: To use or not to use?

BACKGROUND

Postoperative ileus (POI) is a major cause of morbidity, increased length of stay (LOS) and hospital cost after colorectal surgery. Alvimopan is a µ-opioid antagonist used to accelerate upper and lower gastrointestinal function after bowel resection. We hypothesized that alvimopan would reduce LOS in patients undergoing colorectal resection with stoma, a situation that has not been evaluated.

METHODS

A retrospective review (2010-2015) identified 58 patients who underwent colorectal resection for benign or malignant disease with stoma creation and received alvimopan. They were case-matched to 58 non-alvimopan patients based on age, BMI, baseline comorbidities, stoma type created and surgical approach. We compared overall LOS, incidence of POI and other postoperative complications.

RESULTS

There were equal numbers of laparoscopic (N = 18) and open resections (N = 40) in the alvimopan group and non-alvimopan group. There were also equal numbers of patients with an ileostomy (N = 37) or colostomy (N = 21) in each group. Overall, 41 patients underwent resection for malignant disease in the alvimopan group compared to 37 in the non-alvimopan group. There was a significant reduction in median LOS overall (alvimopan 5 (4-7) versus control 6 (4.75-9.25) days, P = 0.03). While the 6-day median LOS was similar for patients undergoing ileostomy creation (P = 0.25), alvimopan patients had a 3-day decreased median LOS that approached statistical significance (P = 0.06). The overall 30-day complication rate was higher in the control group (41.4 vs. 51.7%, P = 0.26), but the readmission rate within 30 days was higher in the alvimopan group (19 vs. 13.8%, P = 0.45). Neither of these differences reached statistically significance.

CONCLUSION

The use of alvimopan in patients undergoing colorectal resection with stoma is associated with a significantly shorter LOS, but the increased readmission rate warrants further study. Based on these data, alvimopan should be evaluated in a controlled setting for patients undergoing colorectal resection with colostomy creation.

Chewing gum for enhancing early recovery of bowel function after caesarean section

BACKGROUND

Caesarean sections (CS) are the most frequent major surgery in the world. A transient impairment of bowel motility is expected after CS. Although this usually resolves spontaneously within a few days, it can cause considerable discomfort, require symptomatic medication and delay hospital discharge, thus increasing costs. Chewing gum in the immediate postoperative period is a simple intervention that may be effective in enhancing recovery of bowel function in other types of abdominal surgeries.

OBJECTIVES

To assess the effects of chewing gum to reduce the duration of postoperative ileus and to enhance postoperative recovery after a CS.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (20 June 2016), LILACs (20 June 2016), ClinicalTrials.gov (20 June 2016), WHO International Clinical Trials Registry Platform (ICTRP) (20 June 2016) and the reference lists of retrieved studies.

SELECTION CRITERIA

All randomised controlled trials comparing chewing gum versus usual care, for women in the first 24 hours after a CS. We included studies published in abstract form only.Quasi-randomised, cross-over or cluster-randomised trials were not eligible for inclusion in this review.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected the studies for inclusion, extracted data and assessed the risk of bias following standard Cochrane methods. We present dichotomous outcome results as risk ratio (RR) with 95% confidence intervals (CI) and continuous outcome results as mean differences (MD) and 95% CI. We pooled the results of similar studies using a random-effects model in case of important heterogeneity. We used the GRADE approach to assess the overall quality of evidence.

MAIN RESULTS

We included 17 randomised trials (3149 participants) conducted in nine different countries. Seven studies (1325 women) recruited exclusively women undergoing elective CS and five studies (833 women) only included women having a primary CS. Ten studies (1731 women) used conventional feeding protocols (nil by mouth until the return of intestinal function). The gum-chewing regimen varied among studies, in relation to its initiation (immediately after CS, up to 12 hours later), duration of each session (from 15 to 60 minutes) and number of sessions per day (three to more than six). All the studies were classified as having a high risk of bias due to the nature of the intervention, women could not be blinded and most of the outcomes were self-reported.Primary outcomes of this review: for the women that chewed gum, the time to passage of first flatus was seven hours shorter than those women in the 'usual care' control group (MD -7.09 hours, 95% CI -9.27 to -4.91 hours; 2399 women; 13 studies; random-effects Tau² = 14.63, I² = 95%, very low-quality evidence). This effect was consistent in all subgroup analyses (primary and repeat CS, time spent chewing gum per day, early and conventional feeding protocols, elective and non-elective CS and time after CS when gum-chewing was initiated). The rate of ileus was on average over 60% lower in the chewing-gum group compared to the control (RR 0.39, 95% CI 0.19 to 0.80; 1139 participants; four studies; I² = 39%, low-quality evidence). Tolerance to gum-chewing appeared to be high. Three women in one study complained about the chewing gum (but no further information was provided) and none of the studies reported adverse effects (eight studies, 925 women, low-quality evidence).Secondary outcomes of this review: the time to passage of faeces occurred on average nine hours earlier in the intervention group (MD -9.22 hours, 95% CI -11.49 to -6.95 hours; 2016 participants; 11 studies; random-effects Tau² = 12.53, I² = 93%, very low-quality evidence). The average duration of hospital stay was shorter in the intervention compared to the control group (MD -0.36 days, 95% CI -0.53 to -0.18 days; 1489 participants; seven studies; random-effects Tau² = 0.04, I² = 92%). The first intestinal sounds were heard earlier in the intervention than in the control group (MD -4.56 hours, 95% CI -6.18 to -2.93 hours; 1729 participants; nine studies; random-effects Tau² = 5.41, I² = 96%). None of the studies assessed women's satisfaction in relation to having to chew gum. The need for analgesia or antiemetic agents did not differ between the intervention and control groups (average RR 0.50, 95% CI 0.12 to 2.13; 726 participants; three studies; random-effects Tau² = 0.79, I² = 69%).

AUTHORS' CONCLUSIONS

This review found 17 randomised controlled trials (involving 3149 women). We downgraded the quality of the evidence for time to first passage of flatus and of faeces and for adverse effects/intolerance to gum chewing because of the high risk of bias of the studies (due to lack of blinding and self-report). For time to first flatus and faeces, we downgraded the quality of the evidence further because of the high heterogeneity in these meta-analyses and the potential for publication bias based on the visual inspection of the funnel plots. The quality of the evidence for adverse effects/tolerance to gum chewing and for ileus was downgraded because of the small number of events. The quality of the evidence for ileus was further downgraded due to the unclear risk of bias for the assessors evaluating this outcome.The available evidence suggests that gum chewing in the immediate postoperative period after a CS is a well tolerated intervention that enhances early recovery of bowel function. However the overall quality of the evidence is very low to low.Further research is necessary to establish the optimal regimen of gum-chewing (initiation, number and duration of sessions per day) to enhance bowel function recovery and to assess potential adverse effects of and women's satisfaction with this intervention. New studies also need to assess the compliance of the participants to the recommended gum-chewing instructions. Future large, well designed and conducted studies, with better methodological and reporting quality, will help to inform future updates of this review and enhance the body of evidence for this intervention.

The use of alvimopan for postoperative ileus in small and large bowel resections

Transient ileus is a normal physiologic process after surgery. When prolonged, it is an important contributor to postoperative complications, increased length of stay and increased healthcare costs. Efforts have been made to prevent and manage postoperative ileus; alvimopan is an oral, peripheral μ-opioid receptor antagonist, and the only currently US FDA-approved medication to accelerate the return of gastrointestinal function postoperatively.

Randomized clinical trial of postoperative chewing gum versus standard care after colorectal resection

Background

Chewing gum may stimulate gastrointestinal motility, with beneficial effects on postoperative ileus suggested in small studies. The primary aim of this trial was to determine whether chewing gum reduces length of hospital stay (LOS) after colorectal resection. Secondary aims included examining bowel habit symptoms, complications and healthcare costs.

Methods

This clinical trial allocated patients randomly to standard postoperative care with or without chewing gum (sugar‐free gum for at least 10 min, four times per day on days 1–5) in five UK hospitals. The primary outcome was LOS. Cox regression was used to calculate hazard ratios for LOS.

Results

Data from 402 of 412 patients, of whom 199 (49·5 per cent) were allocated to chewing gum, were available for analysis. Some 40 per cent of patients in both groups had laparoscopic surgery, and all study sites used enhanced recovery programmes. Median (i.q.r.) LOS was 7 (5–11) days in both groups (P = 0·962); the hazard ratio for use of gum was 0·94 (95 per cent c.i. 0·77 to 1·15; P = 0·557). Participants allocated to gum had worse quality of life, measured using the EuroQoL 5D‐3L, than controls at 6 and 12 weeks after operation (but not on day 4). They also had more complications graded III or above according to the Dindo–Demartines–Clavien classification (16 versus 6 in the group that received standard care) and deaths (11 versus 0), but none was classed as related to gum. No other differences were observed.

Conclusion

Chewing gum did not alter the return of bowel function or LOS after colorectal resection. Registration number: ISRCTN55784442 (http://www.controlled-trials.com).

No advantage observed

Alvimopan combined with enhanced recovery strategy for managing postoperative ileus after open abdominal surgery: a systematic review and meta-analysis

BACKGROUND

To assess the efficacy and safety of alvimopan in conjunction with enhanced recovery strategy, compared with this strategy alone, in management of postoperative ileus in patients undergoing open abdominal surgery.

METHODS

Electronic databases were comprehensively searched for relevant randomized controlled trials. We were interested in doses of 6 and 12 mg. The efficacy end points included the time to recovery of full gastrointestinal (GI) function (a composite end point measured by the time to first toleration of solid food [SF] and the time to first passage of stool, GI-2), the recovery of upper (SF) or the lower (the time to first bowel movement, BM) GI function, and the length of hospital stay (the time to discharge order written). Safety end points included GI-related, non-GI-related, and serious adverse events. These parameters were all analyzed by RevMan 5.3 software.

RESULTS

Nine randomized controlled trials involving 4075 patients were enrolled in this study. The pooled results showed that alvimopan significantly decreased the time to GI-2 recovery (6 mg, hazard ratio [HR] = 1.45, P < 0.00001; 12 mg, HR = 1.59, P < 0.00001), BM (6 mg, HR = 1.54, P < 0.00001; 12 mg, HR = 1.74, P = 0.0002), and the time to discharge order written (6 mg, HR = 1.37, P < 0.00001; 12 mg, HR = 1.34, P < 0.00001) compared with the placebo group. However, SF was significantly reduced in 6 mg group (HR = 1.23, P = 0.008) rather than 12 mg group (HR = 1.14, 95% confidence interval 1.00, 1.30, P = 0.04). The incidence of some GI-related and serious adverse events were significantly lower in the alvimopan group than the placebo group, and the dose of 12 mg was superior to 6 mg in this regard.

CONCLUSIONS

Alvimopan can accelerate recovery of GI function (especially for the lower GI tract), shorten the length of hospital stay, and reduce postoperative ileus-related morbidity without compromising opioid analgesia in an enhanced recovery setting.