Guidelines for management of home parenteral support in adult chronic intestinal failure patients

Life on the line - Incidence and management of central venous catheter complications in intestinal failure

BACKGROUND & AIMS

Loss of venous access is threatening for patients with intestinal failure (IF) under long-term parenteral nutrition (PN). We aimed to identify the incidence of central venous catheter (CVC) complications, compare different devices, and analyze interventional recanalizing procedures to restore the patency of occluded CVCs.

METHODS

For this retrospective cohort study, patient data from a prospective IF database spanning 16 years was analyzed at a tertiary referral center. Catheter dwell times (CDTs) were distinguished by Kaplan-Meier survival analysis and subgroup analyses were performed for different CVC types (tunneled/port catheters). Specific complications (occlusion, catheter-related infection (CRI), displacement, and material defect) were analyzed. Explantation rates and CDTs were compared.

RESULTS

Overall, 193 CVCs in 77 patients with IF under PN could be enrolled (62.524 "CVC-days"). Broviac type "B" was found to be significantly superior to type "A" regarding occlusion, CRI, and material defects (log-rank test: p = 0.05; p = 0.026; p = 0.005 respectively). Port catheters were displaying the highest incidence of CRI (2.13 events/1000 catheter days). Interventional catheter recanalization was performed 91 times and significantly increased the CDT from a median of 131 days (IQR: 62; 258) to 389 days (IQR: 262; 731) (Mann-Whitney-U-test: p= <0.001) without increasing complications.

CONCLUSIONS

Different complication rates and CDT were seen depending on CVC type. Tunneled catheters were significantly superior concerning CRI. Interventional catheter recanalization is a viable alternative to fibrinolytics to restore CVC patency, but long-term patency data is scarce.

Emerging drugs for the treatment of short bowel syndrome

INTRODUCTION

SBS is a rare and disabling condition. The standard management is based on diet optimization with parenteral supplementation. In addition, glucagon-like peptide-2 (GLP-2)analogs, have shown promising results as disease-modifying therapies for SBS.

AREAS COVERED

Short bowel syndrome (SBS) is defined as a reduction in functional intestinal length to less than 200 cm, leading to intestinal failure (IF) leading to malnutrition and parenteral support dependency. This review discusses the current management of SBS-CIFpatients, the place of GLP-2 analog treatment in terms of efficacy, safety and availability, and the new perspectives opened by the use of enterohormones.

EXPERT OPINION

Clinical trials and real-world experience demonstrated that Teduglutide   reduces dependence on parenteral support and has a place in the management of patients with SBS-CIF.  The use of Teduglutide should be discussed in patients stabilized after resection and its introduction requires the advice of an expert center capable of assessing the benefit-risk ratio. The complex, individualized management of SBS-C IF requires theexpertise of a specialized IF center which a multidisciplinary approach. The arrival of new treatments will call for new therapeutic strategies, and the question of how to introduce and monitor them will represent a new therapeutic challenge.

Important issues in proposing autonomy training in home parenteral nutrition for short bowel syndrome patients: a qualitative insight from the patients' perspectives

OBJECTIVES

The standard treatment for short bowel syndrome is home parenteral nutrition. Patients' strict adherence to protocols is essential to decrease the risk of complications such as infection or catheter thrombosis. Patient training can even result in complete autonomy in daily care. However, some patients cannot or do not want too much responsibility. However, doctors often encourage them to acquire these skills. Based on qualitative investigations with patients, we wanted to document issues of importance concerning perceptions of autonomy in daily care.

METHODS

Semistructured interviews were conducted with 13 adult patients treated by home parenteral nutrition using a maximum variation sampling strategy. We proceeded to a thematic analysis following an inductive approach.

RESULTS

After achieving clinical management of symptoms, a good quality of life is within the realm of possibility for short bowel syndrome patients with home parenteral nutrition. In this context, achieving autonomy in home parenteral nutrition could be a lever to sustain patients' quality of life by providing better life control. However, counterintuitively, not all patients aim at reducing constraints by reaching autonomy in home parenteral nutrition. First, they appreciate the social contact with the nurses, which is particularly true among patients who live alone. Second, they can feel safer with the nurse's visits. Regaining freedom was the main motivation for patients in the training program and the main benefit for those who were already autonomous.

CONCLUSIONS

Medical teams should consider patients' health locus of control (internal or external) for disease management to support them concerning the choice of autonomy in daily care for parenteral nutrition.

Use of Total Parenteral Nutrition (TPN) as a Vehicle for Drug Delivery

Total Parenteral Nutrition (TPN) is a method of providing nutrients directly into the bloodstream for individuals who are unable to meet their nutritional needs through the normal digestive process or gastrointestinal system. It provides macronutrients and micronutrients in a single container, reducing handling and contamination risks and making it more cost-effective. TPN has the potential to be used as a drug delivery system, with applications in combination therapies, personalized medicine, and integrating advanced technologies. It can enhance drug dosage precision and provide nutritional assistance, potentially reducing hospitalization and improving patient outcomes. However, implementing new applications requires thorough testing and regulatory approval. TPN could be particularly useful in pediatric and geriatric care and could also contribute to global health by combating malnutrition in areas with limited medical resources. Healthcare professionals prepare a sterile solution tailored to each patient's nutritional needs, and administration involves a central venous catheter. However, the simultaneous administration of medications with PN admixtures can result in pharmacological incompatibility, which can impact the stability of the oil-in-water system. The European Society for Clinical Nutrition and Metabolism and the American Society for Parenteral and Enteral Nutrition recommendations advise against including non-nutrient drugs in PN admixtures due to safety concerns. This review focuses on the utilization of Total Parenteral Nutrition (TPN) as a method for delivering drugs. It discusses the benefits and difficulties associated with its commercial application and offers suggestions for future research endeavors.

Central venous catheter (CVC) salvage in case of central line-associated bloodstream infection (CLABSI): A monocentric prospective study in patients on long-term home parenteral nutrition (HPN)

BACKGROUND & AIMS

CLABSI is a major complication in HPN and frequently leads to central venous catheter (CVC) removal. We developed a salvaging attitude in long term HPN patients due to the necessity of venous preservation. The main objective of this study is to determine the prognosis of CLABSI.

METHODS

We followed-up for three months, in an approved HPN centre, a cohort of 250 adult patients receiving HPN with CLABSI from 2018 to 2020. CLABSI was defined by a blood culture growth differential [peripheral blood] - [CVC blood] ≥ 2h. A therapeutic approach to conserve CVC was established according to the department's protocol. The primary endpoint was conservation of CVC with negative CVC and peripheral blood cultures at 3 months without complications.

RESULTS

Data from 30 CLABSIs were collected for 22 HPN patients. The incidence rate of CLABSIs was 0.28 infections/1000 catheter days. Sixteen CVCs were removed immediately, with causes due to the type of germ (staphylococcus aureus: n = 6, candida parapsilosis: n = 4, klebsiella: n = 2), chronic colonization (n = 4) or initial complications (n = 4). Among the 14 non-removed CVC, 11 were maintained at 3 months with blood cultures on CVC and peripheral negative for 9 (80%) of them. 3 CVC were removed during the 3 months follow-up (non-CVC-related sepsis n = 2, and resistant pseudomonas aeruginosa n = 1).

CONCLUSION

The incidence rate of CLABSIs in an expert HPN centre remains low. In case of CLABSIs, according to specific protocol, approximately 50% of CVC were removed immediately (essentially due to bacteriological characteristics). In case of CLABSIs and without initial complication, 80% of CVCs can be maintained at 3 months. These results justify a conservative attitude according to standardized protocol.

Energy Guidance Using Indirect Calorimetry for Intestinal Failure Patients with Home Parenteral Nutrition: The Right Bag Right at the Start

Intestinal failure is defined as the inability to absorb the minimum of macro and micronutrients, minerals and vitamins due to a reduction in gut function. In a subpopulation of patients with a dysfunctional gastrointestinal system, treatment with total or supplemental parenteral nutrition is required. The golden standard for the determination of energy expenditure is indirect calorimetry. This method enables an individualized nutritional treatment based on measurements instead of equations or body weight calculations. The possible use and advantages of this technology in a home PN setting need critical evaluation. For this narrative review, a bibliographic search is performed in PubMed and Web of Science using the following terms: 'indirect calorimetry', 'home parenteral nutrition', 'intestinal failure', 'parenteral nutrition', 'resting energy expenditure', 'energy expenditure' and 'science implementation'. The use of IC is widely embedded in the hospital setting but more research is necessary to investigate the role of IC in a home setting and especially in IF patients. It is important that scientific output is generated in order to improve patients' outcome and develop nutritional care paths.

Effects of glepaglutide, a long-acting glucagon-like peptide-2 analog, on intestinal morphology and perfusion in patients with short bowel syndrome: Findings from a randomized phase 2 trial

BACKGROUND

The proadaptive effects of glucagon-like peptide-2 (GLP-2) include stimulation of intestinal mucosal growth as well as intestinal blood flow and angiogenesis. We have recently reported that daily subcutaneous injections of glepaglutide, a long-acting GLP-2 analog, improved intestinal absorptive function in patients with short bowel syndrome (SBS). As secondary and exploratory end points, the effects of glepaglutide on intestinal morphology and perfusion are reported.

METHODS

The following assessments were done in 18 patients with SBS in a randomized, crossover, dose-finding, phase 2 trial before and after three weeks of treatment with glepaglutide: plasma citrulline and mucosa biopsies to assess changes in (1) intestinal morphology by immunohistochemistry and (2) gene expressions associated with absorption, proliferation, and markers of tight-junction integrity by quantitative polymerase chain reaction. Intestinal perfusion was assessed in stoma nipples by laser speckle contrast imaging and quantitative fluorescence angiography with indocyanine green.

RESULTS

In the 1- and 10-mg dose groups, glepaglutide significantly increased plasma citrulline by 15.3 µmol/L (P = 0.001) and 15.6 µmol/L (P = 0.001), respectively. Trends toward an increase in villus height, crypt depth, and epithelium height were seen in the same groups. No significant changes were seen in gene expressions or intestinal perfusion.

CONCLUSION

The increase in plasma citrulline and the morphological improvements may partly account for improvement in the intestinal absorptive function. However, the finding of a stability in perfusion after three weeks of treatment with glepaglutide may have been preceded by a more profound acute-phase increase in intestinal perfusion at treatment initiation.

Central venous catheter infection in Canadian home parenteral nutrition patients: a 5-year multicenter retrospective study

HIGHLIGHTS

A lower central venous catheter (CVC) infection rate suggests an improvement in practice and education. CVC infection remains a complication that often requires significant health care resources. Use of tunneled CVC and patient education on catheter care reduces CVC infection rates.

OBJECTIVES

CVC infection is one of the most frequent, life-threatening complications in home parenteral nutrition (HPN) patients. Our objective was to conduct a 5-year retrospective chart review regarding CVC infections in 3 adult HPN programs.

METHODS

Data were collected from the Canadian HPN Registry and patient charts that include demography, infection diagnosis, blood cultures, and treatments.

RESULTS

Results are reported as median (range) ± standard error of mean or population frequency. Eighty-one charts were reviewed. Mean age was 51.98 ± 1.71 years. Short bowel syndrome (54.3%) was the primary diagnosis, with 36 months (range, 1324 months) median length of HPN therapy. Forty-seven subjects (58%) had infections over a 5-year period. Of these, there were 144 sepsis events. There was positive correlation (r=0.423; P<0.001) between number of infections and HPN duration. The median length of time the CVC was in place was 281 (range, 14-4380) days. There were 66.7% tunneled CVCs; 25.9% peripherally inserted central catheters (PICCs), and 7.4% implanted venous port. In this sample, there was no association between line infection and catheter type. Most patients presented with fever (58.3%) and chills (38.2%). Blood cultures were done (89.6%), and coagulase negative Staphylococcus was the resulting pathogen present in 25.7%. Patients with bloodstream infection were treated for 17.9 ± 1.2 days with combination antibiotics (22.2%). Overall, the CVC infection rate was 0.97 per 1000 catheter days.

CONCLUSION

We found the standard approach to infection prevention is comparable to reports in literature. However, a subset of patients with multiple CVC infections require education with an emphasis on preventive techniques in order to reduce the incidence of infection.

Weaning from Parenteral Nutrition

The ultimate goal of treatment of short bowel syndrome/intestinal failure patients is to achieve enteral autonomy by eliminating parenteral nutrition (PN)/intravenous fluids (IV). After optimization of diet, oral hydration and anti-diarrheal medications, attempt should be made to eliminate PN/IV. Weaning from PN/IV should be individualized for each patient. Although teduglutide is the preferred agent for PN/IV volume reduction or successful weaning, optimal patient selection and long-term safety need further evaluation. Following PN/IV elimination, patients need long-term monitoring for nutritional deficiencies. This article will address clinical considerations before, during, and after PN/IV weaning to facilitate safe and successful PN/IV weaning process.

Physicochemical Compatibility and Stability of Linezolid with Parenteral Nutrition

Patients referred to intensive care units (ICU) require special care due to their life-threatening condition, diseases and, frequently, malnutrition. Critically ill patients manifest a range of typical physiological changes caused by predominantly catabolic reactions in the body. It is necessary to provide the patients with proper nutrition, for example by administering total parenteral nutrition (TPN). The addition of linezolid to TPN mixtures for patients treated for linezolid-sensitive infections may reduce the extent of vascular access handling, resulting in a diminished risk of unwanted catheter-related infections. The compatibility and stability studies were conducted of linezolid in parenteral nutrition mixtures of basic, high- and low-electrolytic, high- and low-energetic and immunomodulatory composition. Mixtures containing linezolid were stored at 4–6 °C and 25 °C with light protection and at 25 °C without light protection for 168 h. In order to evaluate changes in the concentration of linezolid a previously validated reversed-phase HPLC method with UV detection was used. It was found that linezolid was stable at 4–6 °C in the whole course of the study whereas at 25 °C it proved stable over a period of 24 h required for administration of parenteral nutrition mixtures. The TPN mixtures demonstrated compatibility with linezolid and suitable stability, which were not affected by time or storage conditions.

Monitoring long-term parenteral nutrition

PURPOSE OF REVIEW

This review discusses the monitoring aimed at achieving good long-term outcomes in people dependent on home parenteral nutrition (HPN).

RECENT FINDINGS

There have been recent studies highlighting the importance of treating low bone mineral density in HPN-dependent patients, methods of screening for liver disease, assessment of quality of life (QoL) and the need for early assessment for intestinal transplantation and growth factor therapy.

SUMMARY

High-quality HPN services require expert multidisciplinary teams with a focus on strict aseptic catheter care protocols alongside regular monitoring and management of clinical, laboratory and patient-related factors. Areas that should be considered in the routine monitoring of HPN include regular laboratory measurements, QoL, assessment for intestinal failure-associated liver disease, treatment of metabolic bone disease and consideration of evolving treatments, alongside management of any underlying condition leading to intestinal failure.

Challenges and Obstacles of Long-Term Home Parenteral Nutrition

Patients receiving long-term home parenteral nutrition (HPN) and clinicians managing their care face complex challenges not fully addressed by existing clinical practice guidelines. This review aims to increase awareness of some of the challenges encountered when managing patients receiving HPN and provide strategies for management. The ability to optimally manage these patients starts with involvement of a qualified team of clinicians, which is sometimes difficult to find. There are unique challenges related to the parenteral nutrition (PN) prescribing and compounding process that are not typically encountered with inpatient use. Clear communication is required between the HPN prescriber/team and the home infusion pharmacist to prevent errors related to misinterpretation of the order and PN product shortages. Dependency on HPN and living with chronic disease create a number of psychosocial, financial, and other lifestyle restrictions that can negatively impact a patient's quality of life. HPN nonadherence is a challenge that complicates the clinician's ability to accurately assess and make appropriate adjustments to therapy. HPN adherence may be improved by incorporating a patient-centered approach to care that allows patients to prioritize those issues most meaningful and valuable to them. Patient-centered care also encourages self-care and relies on a high level of HPN education. Clinicians are encouraged to use an interactive interview style when engaging patients to prioritize goals of care and make self-motivated decisions for change. In spite of challenges, HPN therapy has allowed patients the ability to maintain adequate nutrition and thrive in the home setting when the oral/enteral route fails.

Parenteral therapy and complications in patients with intestinal failure in a regional unit

OBJECTIVE

To describe a cohort of patients with intestinal failure (IF) and tunnelled catheters in a regional IF unit, treatment and catheter-related complication rates, and to compare the quality of care with previously published results from specialised IF centres in Denmark.

METHODS

A retrospective chart review of an adult IF patient cohort receiving parenteral therapy through tunnelled catheters in a regional IF unit from 2005 to 2014. Demographics, indication, type and frequency of parenteral therapy, dwell time, cause of removal and complications were recorded.

RESULTS

Parenteral therapy was provided to 78 patients with a median age of 64 (25-86) years. Numbers increased from seven patients in 2005 to 40 in 2014. The cause of IF was surgical complications (33%), cancer (28%), inflammatory bowel disease (IBD, 15%) and other causes (24%). The median duration of parenteral therapy was 453 days (range: 16-3651 days). One hundred and forty-two tunnelled catheters were inserted. The incidence of catheter-related blood stream infection (CRBSI) was 1.51/1000 days (95% CI: 1.20-1.90) and the incidence of thrombosis was 0.10/1000 days (0.04-0.25). Seventy-two episodes of CRBSI occurred with 89 microorganisms cultured, the most common being coagulase-negative Staphylococcus (n = 25, 28%).

CONCLUSION

The rate of CRBSI did not differ from larger centres in Denmark but the rate of thrombotic events was higher than expected. Parenteral therapy can safely and effectively be offered to patients with IF in smaller centres.

Parenteral Nutrition and Intestinal Failure

Severe short bowel syndrome (SBS) is a major cause of chronic (Type 3) intestinal failure (IF) where structural and functional changes contribute to malabsorption and risk of micronutrient deficiencies. Chronic IF may be reversible, depending on anatomy and intestinal adaptation, but most patients require long-term nutritional support, generally in the form of parenteral nutrition (PN). SBS management begins with dietary changes and pharmacologic therapies taking into account individual anatomy and physiology, but these are rarely sufficient to avoid PN. New hormonal therapies targeting intestinal adaptation hold promise. Surgical options for SBS including intestinal transplant are available, but have significant limitations. Home PN (HPN) is therefore the mainstay of treatment for severe SBS. HPN involves chronic administration of macronutrients, micronutrients, fluid, and electrolytes via central venous access in the patient's home. HPN requires careful clinical and biochemical monitoring. Main complications of HPN are related to venous access (infection, thrombosis) and metabolic complications including intestinal failure associated liver disease (IFALD). Although HPN significantly impacts quality of life, outcomes are generally good and survival is mostly determined by the underlying disease. As chronic intestinal failure is a rare disease, registries are a promising strategy for studying HPN patients to improve outcomes.

Home Initiation of Parenteral Nutrition

Parenteral nutrition (PN) has been successfully initiated in the home since the early 1990s. The American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.) Standards for Specialized Nutrition Support: Home Care Patients, Safe Practices for Parenteral Nutrition, and Guidelines for the Use of Parenteral and Enteral Nutrition in Adult and Pediatric Patients do not contain specific information on the initiation of home PN (HPN). Peer-reviewed, published guidelines are necessary to provide safe and appropriate initiation of HPN. Certain patients should not have PN initiated in the home, such as those with organ failure, uncontrolled diabetes, or uncorrectable electrolyte abnormalities. Excellent candidates for initiation of HPN include patients who have failed enteral feedings, have gastrointestinal (GI) diseases without excessive GI losses, or those with an oncology diagnosis and inability to tube feed. One concern of initiation of HPN is the potential for refeeding syndrome. Refeeding syndrome can be prevented when patients are properly evaluated and managed before initiation of PN. Refeeding syndrome can be avoided by rehydration with fluid and electrolytes before initiation of HPN to normalize blood chemistry when necessary and by starting with a moderate-volume, low-carbohydrate HPN solution compounded with optimal potassium, phosphorus, and magnesium content, and slowly advanced to goal. The "start low and go slow" motto of nutrition support should continue to be followed, but more specific guidelines are needed to assist nutrition support clinicians with safe and appropriate initiation of HPN.

Principles and Strategies for Monitoring Home Parenteral Nutrition

Patients who cannot ingest adequate calories to maintain body weight via their gastrointestinal tract may require parenteral nutrition (PN) at home. As with any therapy, the patient must be evaluated to determine if the home PN (HPN) is effective and the patient is free of complications. This review discusses specific items to monitor for HPN patients. Parameters to monitor can be divided into those used to determine effectiveness and those used to prevent complications of HPN. In addition, potential HPN-associated complications can be divided into those that occur with short- or long-term PN administration. Specific items to monitor are discussed within this framework.

Clinical aspects of neurointestinal disease: Pathophysiology, diagnosis, and treatment

The enteric nervous system (ENS) is involved in the regulation of virtually all gut functions. Conditions referred to as enteric neuropathies are the result of various mechanisms including abnormal development, degeneration or loss of enteric neurons that affect the structure and functional integrity of the ENS. In the past decade, clinical and molecular research has led to important conceptual advances in our knowledge of the pathogenetic mechanisms of these disorders. In this review we consider ENS disorders from a clinical perspective and highlight the advancing knowledge regarding their pathophysiology. We also review current therapies for these diseases and present potential novel reparative approaches for their treatment.

ESPEN guidelines on chronic intestinal failure in adults

BACKGROUND & AIMS

Chronic Intestinal Failure (CIF) is the long-lasting reduction of gut function, below the minimum necessary for the absorption of macronutrients and/or water and electrolytes, such that intravenous supplementation is required to maintain health and/or growth. CIF is the rarest organ failure. Home parenteral nutrition (HPN) is the primary treatment for CIF. No guidelines (GLs) have been developed that address the global management of CIF. These GLs have been devised to generate comprehensive recommendations for safe and effective management of adult patients with CIF.

METHODS

The GLs were developed by the Home Artificial Nutrition & Chronic Intestinal Failure Special Interest Group of ESPEN. The GRADE system was used for assigning strength of evidence. Recommendations were discussed, submitted to Delphi rounds, and accepted in an online survey of ESPEN members.

RESULTS

The following topics were addressed: management of HPN; parenteral nutrition formulation; intestinal rehabilitation, medical therapies, and non-transplant surgery, for short bowel syndrome, chronic intestinal pseudo-obstruction, and radiation enteritis; intestinal transplantation; prevention/treatment of CVC-related infection, CVC-related occlusion/thrombosis; intestinal failure-associated liver disease, gallbladder sludge and stones, renal failure and metabolic bone disease. Literature search provided 623 full papers. Only 12% were controlled studies or meta-analyses. A total of 112 recommendations are given: grade of evidence, very low for 51%, low for 39%, moderate for 8%, and high for 2%; strength of recommendation: strong for 63%, weak for 37%.

CONCLUSIONS

CIF management requires complex technologies, multidisciplinary and multiprofessional activity, and expertise to care for both the underlying gastrointestinal disease and to provide HPN support. The rarity of the condition impairs the development of RCTs. As a consequence, most of the recommendations have a low or very low grade of evidence. However, two-thirds of the recommendations are considered strong. Specialized management and organization underpin these recommendations.

ESPEN endorsed recommendations. Definition and classification of intestinal failure in adults

BACKGROUND & AIMS

Intestinal failure (IF) is not included in the list of PubMed Mesh terms, as failure is the term describing a state of non functioning of other organs, and as such is not well recognized. No scientific society has yet devised a formal definition and classification of IF. The European Society for Clinical Nutrition and Metabolism guideline committee endorsed its "home artificial nutrition and chronic IF" and "acute IF" special interest groups to write recommendations on these issues.

METHODS

After a Medline Search, in December 2013, for "intestinal failure" and "review"[Publication Type], the project was developed using the Delphi round methodology. The final consensus was reached on March 2014, after 5 Delphi rounds and two live meetings.

RESULTS

The recommendations comprise the definition of IF, a functional and a pathophysiological classification for both acute and chronic IF and a clinical classification of chronic IF. IF was defined as "the reduction of gut function below the minimum necessary for the absorption of macronutrients and/or water and electrolytes, such that intravenous supplementation is required to maintain health and/or growth".

CONCLUSIONS

This formal definition and classification of IF, will facilitate communication and cooperation among professionals in clinical practice, organization and management, and research.

Liver disease secondary to intestinal failure

IFALD is a common and potentially life-threatening condition for patients with SBS requiring long-term PN. There exists the potential for decreasing its incidence by optimizing the composition and the rate of infusion of parenteral solutions, by advocating a multidisciplinary approach, and by early referral for intestinal-liver transplantation to ensure long-term survival of patients with SBS.

New perspectives in the diagnosis and management of enteric neuropathies

Chronic disturbances of gastrointestinal function encompass a wide spectrum of clinical disorders that range from common conditions with mild-to-moderate symptoms to rare diseases characterized by a severe impairment of digestive function, including chronic pain, vomiting, bloating and severe constipation. Patients at the clinically severe end of the spectrum can have profound changes in gut transit and motility. In a subset of these patients, histopathological analyses have revealed abnormalities of the gut innervation, including the enteric nervous system, termed enteric neuropathies. This Review discusses advances in the diagnosis and management of the main clinical entities--achalasia, gastroparesis, intestinal pseudo-obstruction and chronic constipation--that result from enteric neuropathies, including both primary and secondary forms. We focus on the various evident neuropathologies (degenerative and inflammatory) of these disorders and, where possible, present the specific implications of histological diagnosis to contemporary treatment. This knowledge could enable the future development of novel targeted therapeutic approaches.

Effects of a multimodal management strategy for acute mesenteric ischemia on survival and intestinal failure

BACKGROUND & AIMS

Acute mesenteric ischemia (AMI) is an emergency with a high mortality rate; survivors have high rates of intestinal failure. We performed a prospective study to assess a multidisciplinary and multimodal management approach, focused on intestinal viability.

METHODS

In an Intestinal Stroke Center, we developed a multimodal management strategy involving gastroenterologists, vascular and abdominal surgeons, radiologists, and intensive care specialists; it was tested in a pilot study on 18 consecutive patients with occlusive AMI, admitted to a tertiary center from July 2009 to November 2011. Patients with left ischemic colitis, nonocclusive AMI, chronic mesenteric ischemia, and other emergencies were excluded. Patients received specific medical management: revascularization of viable small bowel and/or resection of nonviable small bowel; 12 patients received arterial revascularization. We evaluated the percentages of patients who survived for 30 days or 2 years, the number with permanent intestinal failure, and morbidity. Lengths and rates of intestinal resection were compared with or without revascularization, and in patients with early or late-stage disease.

RESULTS

Patients were followed up for a mean of 497 days (range, 7-2085 d); 95% survived for 30 days, 89% survived for 2 years, and 28% had morbidities within 30 days. Intestinal resection was necessary for 7 cases (39%), with mean lengths of intestinal resection of 30 cm and 207 cm, with or without revascularization, respectively (P = .03). Among patients with early or late-stage AMI, rates of resection were 18% and 71%, respectively (P = .049). Patients with early stage disease had shorter lengths of intestinal resection than those with late-stage disease (7 vs 94 cm; P = .02), and spent less time in intensive care (2.5 vs 49.8; P = .02).

CONCLUSIONS

A multidisciplinary and multimodal management approach might increase survival of patients with AMI and prevent intestinal failure.

Faecal D/L lactate ratio is a metabolic signature of microbiota imbalance in patients with short bowel syndrome

Our objective was to understand the functional link between the composition of faecal microbiota and the clinical characteristics of adults with short bowel syndrome (SBS).

Sixteen patients suffering from type II SBS were included in the study. They displayed a total oral intake of 2661±1005 Kcal/day with superior sugar absorption (83±12%) than protein (42±13%) or fat (39±26%). These patients displayed a marked dysbiosis in faecal microbiota, with a predominance of Lactobacillus/Leuconostoc group, while Clostridium and Bacteroides were under-represented. Each patient exhibited a diverse lactic acid bacteria composition (L. delbrueckii subsp. bulgaricus, L. crispatus, L. gasseri, L. johnsonii, L. reuteri, L. mucosae), displaying specific D and L-lactate production profiles in vitro. Of 16 patients, 9/16 (56%) accumulated lactates in their faecal samples, from 2 to 110 mM of D-lactate and from 2 to 80 mM of L-lactate. The presence of lactates in faeces (56% patients) was used to define the Lactate-accumulator group (LA), while absence of faecal lactates (44% patients) defines the Non lactate-accumulator group (NLA). The LA group had a lower plasma HCO3⁻ concentration (17.1±2.8 mM) than the NLA group (22.8±4.6 mM), indicating that LA and NLA groups are clinically relevant sub–types. Two patients, belonging to the LA group and who particularly accumulated faecal D-lactate, were at risk of D-encephalopathic reactions. Furthermore, all patients of the NLA group and those accumulating preferentially L isoform in the LA group had never developed D-acidosis. The D/L faecal lactate ratio seems to be the most relevant index for a higher D- encephalopathy risk, rather than D- and L-lactate faecal concentrations per se. Testing criteria that take into account HCO3⁻ value, total faecal lactate and the faecal D/L lactate ratio may become useful tools for identifying SBS patients at risk for D-encephalopathy.

Determinants of home parenteral nutrition dependence and survival of 268 patients with non-malignant short bowel syndrome

BACKGROUND & AIMS

Short bowel syndrome (SBS) is a rare and severe condition where home parenteral nutrition (HPN) dependence can be either permanent or transient. The timing of HPN discontinuation and the survival, according to SBS characteristics, need to be further reported to help plan pre-emptive intestinal transplantation and reconstructive surgery.

METHODS

268 Non-malignant SBS patients have been followed in our institution since 1980. HPN dependence and survival rate were studied with univariate and multivariate analysis.

RESULTS

Median follow-up was 4.4 (0.3-24) years. Actuarial HPN dependence probabilities were 74%, 64% and 48% at 1, 2 and 5 years, respectively. In multivariate analysis, HPN dependence was significantly decreased with an early (<6 mo) plasma citrulline concentration >20 μmol/l, a remaining colon >57% (4/7) and a remnant small bowel length >75 cm. Among the 124 patients who became HPN independent, 26.5% did so more than 2 years after SBS constitution.

CONCLUSIONS

This study indicates that long-term HPN is required in 47% of SBS patients started on this therapy. HPN independence is significantly associated with the remnant small bowel length, remaining colon and early plasma citrulline concentration. Noteworthy, HPN dependence could be reversed until 5 years after SBS constitution.

Nutritional support in the severely compromised motility patient: when and how?

The management of CIPO remains difficult and requires a multidisciplinary approach. In adult patients with CIPO on HPN, the 10-year survival rate was 68%. Long-term HPN dependence does not seem to be associated with a significant increase in mortality and morbidity. HPN could be a safe and efficient approach to the management of intestinal failure caused by CIPO, with restoring oral intake and lowering hospitalization frequency as major goals of treatment.

Intestinal transplantation: current status and future directions

Three decades after the first intestinal transplant was performed in humans, this life-saving procedure has come of age and now offers hope of long-term survival in a small group of patients with life-threatening complications of intestinal failure and parenteral nutrition. Success rates have greatly improved, largely through advances in immunosuppression protocols, improved surgical technique and postoperative care, and accumulated experience. Management of the intestinal transplant recipient entails careful surveillance, prevention, and treatment of rejection and infection, as well as optimization of feeding and nutrition. With this approach, survival and quality of life are demonstrably improved, such that intestinal transplantation is now an established and accepted procedure for this very select group of highly-complex patients.

Vitamin D deficiency in patients receiving home parenteral nutrition

BACKGROUND

In addition to its role in bone metabolism, vitamin D has important immunomodulatory and antineoplastic effects. Patients on home parenteral nutrition (HPN) receive most of their vitamin D from intravenous (IV) supplementation. Vitamin D deficiency is common in the general population, and the adequacy of vitamin D supplementation in HPN patients is unclear. The purpose of this study is to determine the vitamin D status of patients on HPN.

METHODS

Consecutive patients seen in a regional home nutrition program had their oral and IV vitamin D intakes determined. Plasma 25-hydroxyvitamin D levels were measured in all patients. Intake of calcium, magnesium, and phosphate were also determined.

RESULTS

The mean 25-hydroxyvitamin D level in 22 patients receiving HPN for a mean of 33.5 months (range, 1-177) was 42 nmol/L. Vitamin D deficiency was present in 15 (68%) patients and vitamin D insufficiency in 6 (27%) patients. The mean dietary vitamin D intake was 79.5 IU per day, while the mean IV supplementation was 166 IU per day.

CONCLUSIONS

In this study of a regional Canadian HPN program, there was a high prevalence of vitamin D deficiency/insufficiency affecting virtually all patients. All patients receiving HPN should be supplemented with vitamin D and have their 25-hydroxyvitamin D levels monitored. Further studies are required to determine optimal methods and dosing of vitamin D replacement using oral supplements or ultraviolet light therapy.

Acute intestinal failure in critically ill patients: is plasma citrulline the right marker?

INTRODUCTION

Small bowel functions are more complex than colon functions, and short bowel conditions are associated with increased mortality. Gastrointestinal dysfunction in critically ill patients is common, probably underestimated, and associated with a poor prognosis. However, a validated definition of acute intestinal failure is lacking, in absence of a marker to measure it. Consequently, small bowel dysfunction is not clearly integrated into the overall approach used to treat ICU patients.

MATERIALS AND METHODS

Review of the literature on gastrointestinal dysfunction in critically ill patients, and proposition of a definition of acute intestinal failure.

CONCLUSION

On the one hand, small bowel ischemia is related to acute reduction of enterocyte mass and loss of gut barrier function by epithelial lifting of villi. On the other hand, systemic inflammatory response syndrome (SIRS) and sepsis could be linked to an acute dysfunction of enterocytes without enterocyte reduction. Citrulline is an amino acid mainly synthesized by small bowel enterocytes. Various contexts of chronic and acute reduction of enterocyte mass have been correlated with low plasma citrulline concentration. Critically ill patients with shock have an acute reduction of enterocyte mass and reduced gut citrulline synthesis, leading to a low plasma citrulline concentration. Acute intestinal failure could be defined as an acute reduction of enterocyte mass and/or acute dysfunction of enterocytes, associated or not with loss of gut barrier function. The influence of SIRS and acute renal failure on plasma citrulline concentration and the value of this concentration as an indicator of acute intestinal failure in critically ill patients must be further evaluated.

Frequency of mitochondrial defects in patients with chronic intestinal pseudo-obstruction

BACKGROUND & AIMS

Chronic intestinal pseudo-obstruction (CIPO) is a rare disorder caused by intestinal dysmotility and characterized by chronic symptoms suggesting bowel obstruction in the absence of fixed, occluding lesions. CIPO has been associated with primary defects of the mitochondrial oxidative phosphorylation pathway, although the frequency of mitochondrial disorders in patients with CIPO is unknown. This study evaluates mitochondrial function in patients with CIPO.

METHODS

A retrospective study was performed of data collected from 80 CIPO patients at a tertiary centre over a 25-year period. Mitochondrial disorders were detected by analysis of serum lactate and thymidine phosphorylase activities, brain magnetic resonance images, and muscle biopsies. Genes encoding thymidine phosphorylase, mitochondrial DNA tRNA(leu(UUR)) or tRNA(lys), and DNA polymerase-gamma were analyzed for mutations.

RESULTS

Mitochondrial defects were identified in 15 patients (10 women; median age at diagnosis 32 years), representing 19% of the study cohort. All 15 patients had extra-digestive symptoms, 5 had mutations in the thymidine phosphorylase gene, 2 had mutations in tRNA(leu(UUR)), and 5 had mutations in the DNA polymerase-gamma gene. No genetic defect was detected in 3 of the patients with mitochondrial disorders. Patients with mitochondrial CIPO differed from patients without mitochondrial defects in their very severe nutritional status (frequent and long-term requirement for parenteral nutrition) and poor prognosis (frequent digestive and neurologic complications that led to a high incidence of premature death).

CONCLUSION

Mitochondrial disorders seem to be an important cause of CIPO. Patients with CIPO, especially severe cases with associated neurologic symptoms, should be tested for mitochondrial defects.