Irreversible intestinal failure, nutrition support, and small bowel transplantation

Nutrition Management of Small Bowel Transplant Patients

Nutrition therapy after small bowel or combined liver/small bowel transplantation is challenging. The objective is to restore enteral autonomy to a patient with a complex past surgical history and equally complex posttransplant immunosuppressive regimen in the context of a newly created surgical anatomy. Improved surgical techniques and immunosuppressive regimens have led to superior outcomes. Accompanying these advances is a range of nutrition issues that require specific management strategies. This review outlines the current clinical practice and decision making used to create individualized nutrition regimens for small bowel or combined liver/small bowel transplant recipients. Successful small bowel transplant outcomes require a coordinated effort from a transplant team to restore nutritional autonomy to transplant recipients and free them from parenteral nutrition.

Application of a self-made swivel intravenous transfusion device in constructing allogenic small bowel transplantation rejection model in rats

BACKGROUND

Lacking a long-term continuous intravenous infusion device for experimental animals is the biggest obstacle to constructing an allogenic small bowel transplantation rejection model.

OBJECTIVE

To establish a rat heterotopic small bowel transplantation model with the use of a swivel device for intravenous transfusion.

METHODS

The randomized block design of controlled observations included 90 inbred male F344/NCrl BR rats as donors and 90 LEW/Crl rats as recipients. On the basis of body weight, the rats were divided into three groups each with 30 pairs of rats. Group 1, the control group, underwent small bowel transplantation. Group 2, the transfusion group, received small bowel transplantation and continuous infusion of parenteral nutrient solution. Group 3, the tacrolimus (FK506) treatment group, received small bowel transplantation, continuous infusion of parenteral nutrient solution, and intravenous injection of FK506. The general status and survival time of transplanted rats were observed for 5 weeks.

RESULTS

The operative success rate was 100%. The survival rate was 83.3% (25/30) in the control group; and 96.7% (58/60) in groups 2 and 3 (P = .039). The mean survival time of the FK506 group was 22.1 +/- 13.4 days, which was significantly higher than that in the transfusion group (10.4 +/- 2.9 days, P = .023).

CONCLUSION

The simple, practical swivel intravenous infusion device provided treatment for more than 30 days, a useful tool for heterotopic segmental small bowel transplantation.

Gene expression profile in rat small intestinal allografts after cold preservation/reperfusion

AIM: To determine the changes of gene expression profile in small intestinal allografts in rats after cold preservation/reperfusion, and to identify the genes relevant to cold preservation/reperfusion injury.

METHODS: Heterotopic segmental small bowel transpla-ntation was performed in six rats with a sham operation and they were used as controls. Total RNA was extracted from the allografts (experimental group) and normal intestines (control group) 1 h after cold preservation/reperfusion, and then purified to mRNA, which was then reversely transcribed to cDNA, and labeled with fluorescent Cy5-dUTP and Cy3-dUTP to prepare hybridization probes. The mixed probes were hybridized to the cDNA microarray. After high-stringent washing, the fluorescent signals on cDNA microarray chip were scanned and analyzed.

RESULTS: Among the 4 096 target genes, 82 differentially expressed genes were identified between the two groups. There were 18 novel genes, 33 expression sequence tags, and 31 previously reported genes. The selected genes may be divided into four classes: genes modulating cellular adhesion, genes regulating cellular energy, glucose and protein metabolism, early response genes and other genes.

CONCLUSION: A total of 82 genes that may be relevant to cold preservation/reperfusion injury in small intestinal allografts are identified. Abnormal adhesion between polymorphonuclears and endothelia and failure in energy, glucose and protein metabolism of the grafts may contribute to preservation/reperfusion injury. The functions of the novel genes identified in our study need to be clarified further.

Is portal venous outflow better than systemic venous outflow in small bowel transplantation? Experimental study in syngeneic rats

BACKGROUND/PURPOSE

Blood drainage of the graft into the recipient portal vein reestablishes the physiological venous outflow after small bowel transplantation (SBT). However, although this approach is likely beneficial for the host, it may be technically more demanding making portocaval venous drainage the preferred arrangement during human SBT. The aim of this study was to examine in a syngeneic model of SBT the possible benefits of portoportal anastomosis (PPA) vs portocaval anastomosis (PCA) in terms of body and organ weights and bacterial translocation.

METHODS

Syngeneic SBT was carried out in 25 Brown-Norway male rats weighing 249 +/- 17.5 g using either PPA (n = 13) or PCA (n = 12). Half the animals in each group were killed, respectively, on postoperative day 2 or 7. Liver, spleen, and lungs were weighed and under sterile conditions the regional lymph nodes were excised. The nodes and venous samples from the cava and portal veins were cultured for aerobes and anaerobes. Bacterial components were detected in blood by polymerase chain reaction. The findings in both groups were compared by chi2 or Mann-Whitney U tests.

RESULTS

Mean postoperative body weight change was -3.6% +/- 1.5% in PPA and -6.0% +/- 1.2% in PCA animals (ns) on day 2 and -6.5% +/- 2.6% and -8.0% +/- 5.0% (ns) on day 7. Liver, spleen, and lung weights were not significantly different between both groups on either end point. Gram-negative enteric bacteria were found in 3 of 7 PCA animals and 2 of 6 PPA animals at day 2 (ns) and in 1 of 6 and 4 of 6 on day 7 (ns). Aerobic gram-positive bacteria were found in 1 of 7 and 1 of 6 (ns), 3 of 6 and 3 of 6 (ns), respectively, in the 4 groups. Most positive cultures corresponded to portal blood and lymph node samples. There were no anaerobic growths.

CONCLUSIONS

-No body or organ weight change suggesting significant functional advantages of one technical alternative over the other could be demonstrated. -Bacterial translocation in the absence of rejection was frequent after SBT independently of the variety of venous outflow used. No difference in bacterial translocation between both anastomosis could be demonstrated. -Orthotopic venous drainage did not seem to be advantageous in the present experimental setting.

[Apoptosis participation in the acute rejection of intestinal transplantation in rats]

BACKGROUND

Intestinal transplantation is a possible treatment for patients with short bowel syndrome, aiming the reintroduction of oral diet. However, the major obstacle in this procedure is the strong rejection. Delay in rejection diagnosis may be irreversible and lethal.

AIM

To define method for early diagnosis of rejection based on the apoptosis from intestinal allograft.

MATERIAL AND METHODS

Isogenic rats Brown-Norway (BN) and Lewis (LEW) were submitted to intestinal heterotopic allotransplantation and divided in two groups: LEW donor to LEW recipient isograft group C and BN donor to LEW recipient allograft group (Tx). According to the day of sacrifice, Tx group were subdivided in three subgroups with eight animals each as follow: Tx3-- sacrificed at third postoperative day (POD), Tx5 -- sacrificed at fifth POD and Tx7 -- sacrificed at seventh POD. Eight animals from control group were subdivided in three moments according to the time of biopsy from the graft as follow: C3 -- biopsy at third POD; C5 -- biopsy at fifth POD and C7 -- biopsy at seventh POD. All animals from control group were sacrificed at seventh POD. Rejection parameters were compared between the control groups (C3 vs C5, C3 vs C7 and C5 vs C7, and allograft group (Tx3 vs Tx5, Tx3 vs Tx7 and Tx5 vs Tx7). The same parameters were analyzed between the control group and allograft groups ( C3 vs Tx3, C5 vs Tx5 and C7 vs Tx7). In C group no statistical significant difference regarding the expression of the apoptotic cells were detected, while in Tx group, the presence of apoptotic cells were remarkable since the third postoperative day.

[Cytokine participation in the acute rejection of intestinal transplantation in rats]

BACKGROUND

Intestinal transplantation is a possible treatment for patients with short bowel syndrome, aiming the reintroduction of oral diet. However, the major obstacle in this procedure is the strong rejection. Delay in rejection diagnosis may be irreversible and lethal.

AIM

To define method for early diagnosis of rejection based on the presence of interleucin-6 (IL-6) e interferon- gamma (IFN-gamma) from intestinal allograft.

MATERIAL AND METHODS

Isogenic rats Brown-Norway (BN) and Lewis (LEW) were submitted to intestinal heterotopic allotransplantation and divided in two groups: LEW donor to LEW recipient isograft group (C) and BN donor to LEW recipient allograft group (Tx). According to the day of sacrifice, Tx group were subdivided in three subgroups with eight animals each as follow: Tx3--sacrificed at third postoperative day (POD), Tx5--sacrificed at fifth POD and Tx7--sacrificed at seventh POD. Eight animals from control group were subdivided in three moments according to the time of biopsy from the graft as follow: C3--biopsy at third POD; C5--biopsy at fifth POD and C7--biopsy at seventh POD. All animals from control group were sacrificed at seventh POD. Rejection parameters were compared between the control groups (C3 vs C5, C3 vs C7 and C5 vs C7, and allograft group (Tx3 vs Tx5, Tx3 vs Tx7 and Tx5 vs Tx7). The same parameters were analyzed between the control group and allograft groups (C3 vs Tx3, C5 vs Tx5 and C7 vs Tx7).

RESULTS

In C group no statistical significant difference regarding the immunoexpression of the cytokines, while in Tx group, immunoexpression of IL-6 and IFN-gamma were remarkable since the fifth postoperative day.

Italian guidelines for intestinal transplantation: potential candidates among the adult patients managed by a medical referral center for chronic intestinal failure

In 2002, the Italian guidelines for eligibility of patients for intestinal transplantation (ITx) were defined as: life-threatening complications of home parenteral nutrition (HPN), lack of venous access for HPN, locally invasive tumors of the abdomen, Chronic intestinal failure (CIF) with a high risk of mortality, primary disease-related poor quality of life (QoL) despite optimal HPN. Our aim was to identify potential candidates for ITx according to these national guidelines among patients managed by a medical referral center for CIF. Records of patients who received HPN were reviewed. CIF was considered reversible or irreversible (energy by HPN <50% or >50% basal energy expenditure). Patients with irreversible CIF were considered eligible for ITx in the absence of a contraindication, as are used for solid organs Tx. From 1986 to 2003 among 64 patients who met the entry criteria 23 showed reversible and 41 irreversible, CIF. Twenty-one patients with irreversible CIF had an indication for ITx, but eight had also contraindications; thus 13 were eligible, including intestinal pseudo-obstruction (n = 6), mesenteric ischemia (n = 3), Crohn's (n = 2), radiation enteritis (n = 1), and desmoid (n = 1). Indications for ITx included HPN liver failure (n = 2), lack of venous access (n = 2), CIF with high risk of mortality (n = 3), very poor QoL (n = 6 including 5 with pseudo-obstruction). According to the Italian guidelines for ITx, 31% of patients with irreversible CIF managed by a medical referral center were eligible for ITx. Primary disease-related poor QoL was the indication in half of them. Studies on the QoL after ITx are required to allow patients to make an educated decision.

Management of a small bowel transplant with complicated central venous access in a patient with asymptomatic superior and inferior vena cava obstruction

During the past few years, small bowel transplantation (SBT) has become a realistic alternative for patients with irreversible intestinal failure who have or will develop severe complications from total parenteral nutrition (TPN). Transplantation can be associated with large fluid shifts and massive blood loss necessitating rapid infusions of large quantities of crystalloid and/or blood products. Invasive monitoring and large-bore venous access are necessary in order to manage these patients intraoperatively. Because patients with irreversible intestinal failure are often managed with total parenteral nutrition via a central venous catheter, thrombotic intraluminal obstruction of major vessels may develop over time. Additionally, this may lead to superior vena cava (SVC) syndrome as well as challenging problems with vascular access. We present a 34-year-old woman with a past medical history for long-standing Crohn's disease with multiple small bowel resections and short gut syndrome who presented for an SBT. The patient had a long history of TPN use, complicated by SVC syndrome and inferior vena cava (IVC) obstruction. She was presently asymptomatic from her SVC obstruction. Central venous access was obtained by an interventional radiologist. A 7-French double-lumen Hickman minicatheter was placed in the left femoral vein with the tip of the catheter positioned just distal to the IVC narrowing. A left radial 20-gauge arterial line was placed for hemodynamic monitoring and frequent blood sampling. The patient's left and right dorsal-saphenous veins were cannulated with 16-guage catheters and adequate flow was observed. Lower extremity pressure was measured via the Hickman catheter in the left femoral vein. A multiplane transesophageal echo was used to assess ventricular volume. The options and intraoperative management of such patients are discussed.

Modifications in combined liver-small bowel transplantation in pigs

AIM: To introduce combined liver-small bowel transplantation in pigs.

METHODS: Eighteen transplantations in 36 large white pigs were performed. Three modifications in combined liver-small bowel transplantation model were applied: Veno-venous bypass was not used. Preservation of the donor duodenum and head of pancreas in continuity with the combined graft to avoid biliary reconstruction. The splenic vein of donor was anastomosed end-to-end with the portal vein of recipients by the formation of a “cuff”.

RESULTS: Without immunosuppressive therapy, 72-hour survival rate of the transplanted animals was 72% (13/18). Five of 18 pigs operated died of respiratory failure (3 cases) and bleeding during hepatectomy (2 cases). The longest survival time of animals was 6 days.

CONCLUSION: Our surgical modifications are feasible and reliable, which have made the transplantation in pigs simpler and less aggressive, and thus these can be used for preclinical study.

Early protective effect of ischemic preconditioning on small intestinal graft in rats

AIM: To investigate the early protective effect of ischemic preconditioning on small intestinal graft in rats.

METHODS: SD rats were randomly divided into the following groups: sham operation group (S group, n = 6), small bowel transplantation group (SBT group, n = 12), ischemic preconditioning plus small bowel transplantation group (ISBT group, n = 12). Heterotopic SBT was performed with a technique modified from that described by Monchik et al When the graft was revascularized successfully and reperfused for 1 h, samples were obtained from the different groups. Laminin was analyzed with immunohistochemical staining. Quantitative analysis of laminin positive signals was performed using image acquiring analysis system. Apoptotic epithelia of small intestinal graft were detected by the TdT-mediated dUTP nick end labeling method. The morphological change of epithelial basement membrane was observed by transmission electron microscopy.

RESULTS: The mean optical density value of laminin positive signals was 39.52 ± 2.60, 13.53 ± 0.44, 25.40 ± 1.79, respectively, in S, SBT and ISBT groups. The average optical density value of laminin positive products in SBT group was sharply lower than that in S group (P < 0.05). However, the mean optical density value of laminin positive products in ISBT group was significantly higher than that in SBT group (P < 0.05). The apoptotic index (AI) in S, SBT and ISBT group was 2.2 ± 0.83,30.8 ± 3.2, 13.2 ± 2.86, respectively. The AI in SBT group was significantly higher than that in S group (P < 0.05), and AI in ISBT group was sharply lower than that in SBT group (P < 0.05). On transmission electron microscopy, the epithelial basement membrane in S group stayed normal, but in SBT group it became disrupted and collapsed, even disappeared. The lesion of epithelial basement membrane in ISBT group was slighter compared with that in SBT group.

CONCLUSION: Ischemic preconditioning has an early protective effect on epithelial cells and extracellur matrix of small intestinal graft. Inhibition of epithelial cell apoptosis may be one of the mechanisms of ischemic preconditioning.

Transplante de intestino delgado

RACIONAL: Avanços da biotecnologia e o desenvolvimento de novas drogas imunossupressoras melhoraram os resultados do transplante de intestino delgado. Esse transplante é atualmente indicado para casos especiais da falência intestinal. OBJETIVO: A presente revisão realça os recentes desenvolvimentos na área do transplante de intestino delgado. MATERIAL E MÉTODO: Mais de 600 publicações de transplante de intestino delgado foram revisadas. O desenvolvimento da pesquisa, novas estratégias de imunossupressão, monitorização do enxerto e do receptor, e avanços na técnica cirúrgica são discutidos. RESULTADOS: Realizaram-se cerca de 700 transplante de intestino delgado em 55 centros: 44% intestino-fígado, 41% enxerto intestinal isolado e 15% transplante multivisceral. Rejeição e infecção são as principais limitações desse transplante. Sobrevida de 5 anos na experiência internacional é de 46% para o transplante de intestino isolado, 43% para o intestino-fígado e de cerca de 30% para o transplante multivisceral. Sobrevidas prolongadas são mais freqüentes nos centros com maior experiência. Em série de 165 transplantes intestinais na Universidade de Pittsburgh, PA, EUA, foi relatada sobrevida do paciente maior do que 75% no primeiro ano, 54% em 5 anos e 42% em 10 anos. Mais de 90% desses pacientes assumem dieta oral irrestrita. CONCLUSÃO: O transplante de intestino delgado evoluiu de estratégia experimental para uma alternativa viável no tratamento da falência intestinal permanente. Promover o refinamento da terapia imunossupressora, do manejo e prevenção de infecções, da técnica cirúrgica e da indicação e seleção adequada dos pacientes é crucial para melhorar a sobrevida desse transplante.

The effects of the formula of amino acids enriched BCAA on nutritional support in traumatic patients

AIM: To investigate the formula of amino acid enriched BCAA on nutritional support in traumatic patients after operation.

METHODS: 40 adult patients after moderate or large abdominal operations were enrolled in a prospective, randomly and single-blind-controlled study, and received total parenteral nutrition (TPN) with either formula of amino acid (AA group, 20 cases) or formula of amino acid enriched BCAA (BCAA group, 20 cases). From the second day after operation, total parenteral nutrition was infused to the patients in both groups with equal calorie and equal nitrogen by central or peripheral vein during more than 12 hours per day for 6 days. Meanwhile, nitrogen balance was assayed by collecting 24 hours urine for 6 days. The markers of protein metabolism were investigated such as amino acid patterns, levels of total protein, albumin, prealbumin, transferrin and fibronectin in serum.

RESULTS: The positive nitrogen balance in BCAA group occurred two days earlier than that in AA group. The serum levels of total protein and albumin in BCAA group were increased more obviously than that in AA group. The concentration of valine was notably increased and the concentration of arginine was markedly decreased in BCAA group after the formula of amino acids enriched BCAA transfusion.

CONCLUSION: The formula of amino acid enriched BCAA may normalize the levels of serum amino acids, reduce the proteolysis, increase the synthesis of protein, improve the nutritional status of traumatic patients after operation.

Review article: nutrition and adult inflammatory bowel disease

Major advances in the understanding of the aetio-pathogenesis and genetics of inflammatory bowel disease have been accompanied by an escalation in the sophistication of immunomodulatory inflammatory bowel disease therapeutics. However, the basic 'triple' therapy (5-aminosalicylates, corticosteroids, azathioprine) and nutrition have maintained their central role in the management of patients with inflammatory bowel disease over recent decades. This review provides an overview of the supportive and therapeutic perspectives of nutrition in adult inflammatory bowel disease. The objective of supportive nutrition is to correct malnutrition in terms of calorie intake or specific macro- or micronutrients. Of particular clinical relevance is deficiency in calcium, vitamin D, folate, vitamin B12 and zinc. There is justifiably a growing sense of unease amongst clinicians and patients with regard to the long-term use of corticosteroids in inflammatory bowel disease. This, rather than arguments about efficacy, should be the catalyst for revisiting the use of enteral nutrition as primary treatment in Crohn's disease. Treatment failure is usually related to a failure to comply with enteral nutrition. Potential factors that militate against successful completion of enteral nutrition are feed palatability, inability to stay on a solid-free diet for weeks, social inconvenience and transient feed-related adverse reactions. Actions that can be taken to improve treatment outcome include the provision of good support from dietitians and clinicians for the duration of treatment and the subsequent 'weaning' period. There is evidence to support a gradual return to a normal diet through exclusion-re-introduction or other dietary regimen following the completion of enteral nutrition to increase remission rates. We also review the evidence for emerging therapies, such as glutamine, growth factors and short-chain fatty acids. The future may see the evolution of enteral nutrition into an important therapeutic strategy, and the design of a 'Crohn's disease-specific formulation' that is individually tailored, acceptable to patients, cost-effective, free from adverse side-effects and combines enteral nutrition with novel pre- and pro-biotics and other factors.

Role of changes in tissular nucleotides on the development of apoptosis during ischemia/reperfusion in rat small bowel

The aim of this study was to evaluate whether xanthine and adenosine, substances modified proportionally to the duration of ischemia, can determine cell demise (apoptosis/necrosis) during intestinal ischemia/reperfusion (I/R) and to determine the role of nitric oxide (NO) during this process. The following experimental groups were studied: I, cold ischemia; I+X, effect of xanthine; I+T, effect of adenosine (blocking its receptor by theophylline); I+A, effect of excess adenosine; I+T+X, effect of xanthine alone, and I+T+ spermine NONOate (NONOs), I+A+NONOs, I+X+NONOs, role of NO. DNA fragmentation, xanthine/adenosine levels, caspase-3 activity, NO generation, and histological analysis were measured in tissue samples. The rats treated with xanthine or adenosine showed increased levels of caspase-3 activity and DNA fragmentation. In contrast, theophylline-treated rats showed decreased levels of DNA fragmentation and tended to show lower mean values of caspase-3 activity. Administration of xanthine or NONOs to theophylline-treated rats reversed these effects. The results of histological evaluation were in agreement with these previous results. In conclusion, the present study indicates that xanthine and adenosine induced an apoptotic response during cold ischemic preservation of rat small intestine. In particular, the action of adenosine on apoptotic events was mediated by NO. We consider that identification of the role of these factors may help to define the best conditions of tissue preservation before intestinal transplantation.

Combined small bowel and reduced auxiliary liver transplantation: Case report

AIM: To present a case of combined small bowel and reduced auxiliary liver transplantation.

METHODS: A 55-year-old patient with short bowel syndrome and TPN-related liver dysfunction received small bowel transplantation combined with a reduced auxiliary liver graft. A liver was added to restore the patient's liver function and to protect the intestinal allograft from rejection. His own liver was not removed.

RESULTS: Without donor pretreatment and by conventional immunosuppresive therapy following transplantation, the patient experienced had only one episode of mild intestinal rejection, which was easily reversed by treatment with Methylprednisolone. No liver rejection occurred. Unfortunately, the patient died of heart and lung failure 30 d after transplantation, despite successful graft replacement. Histopathologic examination of specimens after death demonstrated normal structure in both intestinal and liver grafts.

CONCLUSION: The auxiliary liver graft might play a role in preventing intestinal allograft rejection. However, the observation period in this case is short. Further study is needed to determine the risks, effect on the protecting the small-bowel from rejection, and feasibility of general application of this procedure.