Pathophysiology of Ascites: The importance of the intestine. A surgical contribution to the understanding of a medical problem.

The understanding of the mechanisms for the development of ascites has evolved over the years, involving the liver, peritoneum, heart, and kidneys as key responsible for its formation. In this article, we review the pathophysiology of ascites formation, introducing the role of the intestine as a major responsible for ascites production through "a game changer" case.

Power Management Unit for Solar Energy Harvester Assisted Batteryless Wireless Sensor Node.

This work describes an energy-efficient monolithic Power Management Unit (PMU) that includes a charge pump adapted to photovoltaic cells with the capability of charging a large supply capacitor and managing the stored energy efficiently to provide the required supply voltage and power to low energy consumption wireless sensor nodes such as RFID sensor tags. The proposed system starts-up self-sufficiently with a light source luminosity equal to or higher than 500 lux using only a 1.42 cm2 solar cell and integrating an energy monitor that gives the ability to supply autonomous sensor nodes with discontinuous operation modes. The system occupies an area of 0.97 mm2 with a standard 180 nm CMOS technology. The half-floating architecture avoids losses of charging the top/button plate of the stray capacitors in each clock cycle. Measurements' results on a fabricated IC exhibit an efficiency above 60% delivering 13.14 µW over 1.8 V. The harvested energy is enough to reach the communication range of a standard UHF RFID sensor tag up to 21 m.

First registry of adult patients with chronic intestinal failure due to short bowel syndrome in Argentina: The RESTORE project.

BACKGROUND: Short bowel syndrome (SBS) is considered a low prevalence disease. In Argentina, no registries are available on chronic intestinal failure (CIF) and SBS. This project was designed as the first national registry to report adult patients with this disease. METHODS: A prospective multicenter observational registry was created including adult patients with CIF/SBS from approved centers. Demographics, clinical characteristics, nutrition assessment, home parenteral nutrition (HPN) management, surgeries performed, medical treatment, overall survival, and freedom from HPN survival were analyzed. RESULTS: Of the 61 enrolled patients, 56 with available follow-up data were analyzed. At enrollment, the mean intestinal length was 59.5 ± 47.3 cm; the anatomy was type 1 (n = 41), type 2 (n = 10), and type 3 (n = 5). At the end of the interim analysis, anatomy changed to type 1 in 31, type 2 in 17, and type 3 in 8 patients. The overall mean time on HPN before enrollment was 33.5 ± 56.2 months. Autologous gastrointestinal reconstruction surgery was performed before enrollment on 21 patients, and afterward on 11. Nine patients (16.1%) were weaned off HPN with standard medical nutrition treatment; 12 patients received enterohormones, and 2 of them suspended HPN; one patient was considered a transplant candidate. In 23.7 ± 14.5 months, 11 of 56 patients discontinued HPN; Kaplan-Meier freedom from HPN survival was 28.9%. The number of cases collected represented 19.6 new adult CIF/SBS patients per year. CONCLUSION: The RESTORE project allowed us to know the incidence, the current medical and surgical approach for this pathology, as well as its outcome and complications at dedicated centers.

Autologous gastrointestinal reconstruction surgery for short bowel syndrome: the cornerstone for intestinal rehabilitation.

PURPOSE OF REVIEW: Intestinal failure (IF) evolved from being the last recognized organ failure, to become one of the most progressive fields in terms of therapeutic alternatives and results. Short bowel syndrome (SBS) is the main cause of IF in adults and children. The use of surgery allowed patients with unfavorable anatomy type and length to be wean off parenteral nutrition. We aim to evaluate its current impact on intestinal rehabilitation. RECENT FINDINGS: Autologous gastro-intestinal reconstructive surgery (AGIRS), including bowel lengthening contributes by converting patient's anatomy to a more favorable one, improving quality of life, and modifying the natural history of the disease, allowing to recover intestinal autonomy in approximately 70% of the adults and 50% of the children's with SBS-IF. The current use of postsurgical medical rehabilitation strategies including the use of enterohormones complement the path to sufficiency, increasing the chances of success in both age group of patients. SUMMARY: The development of AGIRS has changed the outcome of SBS-IF patients, becoming the main surgical procedure prescribed in multidisciplinary units, allowing to enhance the number of patients achieving intestinal autonomy throughout rehabilitation, leaving transplantation as the last surgical alternative.

Induction Versus Maintenance Immunosuppression After Intestinal Transplant: Determining Which Treatment Most Impacts Long-Term Patient And Graft Survival.

OBJECTIVES: Immunosuppressive strategies for intestinal transplant have changed over time. However, specific intestinal transplant-oriented protocols and reports on long-term maintenance regimens are scarce. Our objective was to evaluate the impact of 2 different initial immunosuppressive protocols based on thymoglobulin (group A) and basiliximab (anti-interleukin 2 antibody) (group B) and of changes to maintenance immunosuppression over long-term follow-up in intestinal transplant recipients. MATERIALS AND METHODS: We performed a retrospective analysis of a prospectively established protocol for intestinal transplant immunosuppression, conducted between May 2006 and December 2020. We analyzed 51 intestinal transplant recipients, with 6 patients excluded because of early death or graft loss. Acute cellular rejection frequency and grade, number of acute cellular rejection episodes, time to the first acute cellular rejection episode, response to treatment, number of patients who progressed to chronic allograft rejection, kidney function, infections, incidence of posttransplant lymphoproliferative disorder and graft-versus-host disease, and patient and graft survival were analyzed. RESULTS: In the study groups, there were 87 acute cellular rejection episodes in 45 patients (33 in group A and 54 in group B). We found degree of acute cellular rejection to be mild in 45 patients, moderate in 18, and severe in 24 (not significant between groups). Our comparison of induction therapy (thymoglobulin [group A] vs interleukin 2 antibody [group B]) did not show any statistical difference during clinical followup. Long-term review showed that all patients were on tacrolimus. Five-year patient and graft survival rates were 62% and 45% for group A and 54% and 46% for group B, respectively (not significant). CONCLUSIONS: Long-term patient and graft outcomes reflected the use of an individualized follow-up with adjustments and changes in immunosuppressive medications according to the patient's clinical course and complications rather than based on the induction immunosuppressive protocol used.

Non-conventional vascular accesses for the management of superior vena cava syndrome in patients with Intestinal Failure. Case series and systematic review.

BACKGROUND: Type III Intestinal Failure (IF) is a devastating clinical condition.characterized by the inability of the gut to absorb necessary macronutrients, and/or water and electrolytes, requiring Parenteral Nutrition (PN) as chronic therapy. Long-term PN may lead to life-threatening complications; the loss of central venous access (LCVA) is the most frequent and challenging. To date, few studies in the literature have reported the relevance of Non-conventional Vascular Accesses (NCVA) in the management IF as part of the comprehensive multidisciplinary care. METHODS: A retrospective analysis of a database collected from January 2006 to December 2019 was performed using SPSS v25.0 for statistical analysis, followed by a systematic review, using the PRISMA.methodology RESULTS: From January 2006 to December 2019, 184 NCVA were placed in 71 patients with LCVA as IF-related complication; 173 were placed in 61 patients by interventional radiology (IR) and 11 NCVA were placed in 10 patients by the surgical team during the intestinal transplant (ITx) operation. From the 173 IR procedures 166 (95.9%) were successful with 3 ± 2.7 procedures/patient; average catheter permanence rate was 738.68 ± 997 days; complications related to the procedures occurred in 18/173 (10.4%), including two deaths. On the other hand, among the 11 NCVA implanted by the surgical team, 7 (64%) were successful and were safely withdrawn 30 days after ITx when were no longer needed; 2 (18%) catheters malfunctioned during the first week and could not be further used, and 1 was accidently removed; average catheter permanence rate was 26 ± 4 days. There was one complication (9%) requiring laparotomy; there was no mortality associated the procedure in this group. A systematic review was conducted to evaluate the success and safety of NCVA as part of the treatment of HPN-related complications; from 337,542 papers, 14 studies were included. A total of 28 HPN-patients with LCVA received NCVA; 34 procedures were successfully performed, while procedure-related complications were reported in 11.7%, as well as one death. CONCLUSIONS: The data analyzed show that NCVAs may be successfully placed by expert teams, allowing to sustain long-term PN, as well as increasing the Intestinal Transplantation applicability for candidates in the extreme need of vascular access.

Rehabilitación del intestino utilizando un análogo semisintético del péptido 2 similar al glucagón. Primera experiencia con teduglutide en Uruguay / Intestinal rehabilitation using semisynthetic glucagon-like peptide-2 analogue. First experience with teduglutide in Uruguay / Reabilitação do intestino usando um análogo semi-sintético do peptídeo 2 semelhante ao glucagon. Primeira experiência com teduglutide no Uruguai

Resumen: La falla intestinal crónica (FIC) o tipo III es una condición invalidante, y la nutrición parenteral crónica (NPC) domiciliaria es el tratamiento que permite a estos pacientes mantenerse con vida. Sin embargo, solamente uno de cada tres países latinoamericanos cuentan con ese recurso, y sus complicaciones no son infrecuentes. Estas complicaciones son las principales indicaciones para trasplante intestinal, un procedimiento que en la mayoría de los países de ingresos medios no se ha desarrollado y no ha presentado los resultados esperados. En los últimos años, la rehabilitación intestinal a nivel mundial ha mejorado sustancialmente con el uso de análogos semisintéticos del péptido 2 similares al glucagón, existiendo cada vez mayor evidencia que demuestra la posibilidad de rehabilitación intestinal e independencia de la NPC con este fármaco, incluso en pacientes con anatomía desfavorable. Estos resultados han permitido mejorar la supervivencia y la calidad de vida de pacientes con FIC y, en muchas ocasiones, prescindir del trasplante. El paciente del caso que presentamos es el primero en recibir esta terapéutica en nuestro país. En este artículo analizamos la respuesta precoz favorable al tratamiento y sus perspectivas a futuro.

Abstract: Long-term home parenteral nutrition (HPN) is a life-saving treatment for patients with chronic intestinal failure, an invalidating condition. However, only 1 out of 3 countries can rely on this treatment and complications associated to chronic parenteral nutrition are rather frequent. The latter constitute the main indication for intestinal transplantion, a procedure that in most middle-income countries has not yet developed and has not shown the expected outcome. In recent years, intestinal rehabilitation has significantly improved at the global level with the use of GLP2, based on the growing evidence that proves the possibility of intestinal rehabilitation and independence from parenteral nutrition with Teduglutide, even in the case of patients with unfavorable anatomy. These results have caused a positive impact on survival and the quality of life of patients with chronic renal failure, and they can often abstain from transplant. The patient of the case study is the first one who received this therapy in our country and this article analyses his favorable early response to treatment and future perspectives.

Resumo: A insuficiência intestinal crônica (CIF) ou tipo III é uma condição incapacitante e a nutrição parenteral crônica (NPC) domiciliar é o tratamento que permite a sobrevida desses pacientes. No entanto, apenas 1 em cada 3 países latino-americanos dispõe desse recurso e as complicações da NPC não são raras. Essas complicações são as principais indicações para o transplante intestinal, procedimento que na maioria dos países de renda média não foi desenvolvido ou não apresentou os resultados esperados. Nos últimos anos, a reabilitação intestinal em todo o mundo tem melhorado substancialmente com o uso de sGLP2, com um número cada vez maior de evidências que mostram a possibilidade de reabilitação intestinal e independência da NPC, mesmo em pacientes com anatomia desfavorável. Esses resultados têm possibilitado prolongar a sobrevida e melhorar a qualidade de vida dos pacientes com CIF e, em muitos casos, dispensar o transplante. O paciente do caso que apresentamos é o primeiro a receber essa terapia em nosso país. Neste artigo, analisamos a resposta favorável ao tratamento precoce e suas perspectivas futuras.

Quality of life after intestinal transplantation.

PURPOSE OF REVIEW: Intestinal transplantation (ITx) is the last therapeutic option in chronic intestinal failure (CIF) patients who develop life-threatening complication related to home parenteral nutrition (HPN). Improvement of quality of life (QoL) has been proposed as one of the nonconventional indications for ITx in these patients. This review aims to summarize the current evidence about QoL assessment in ITx recipients. RECENT FINDINGS: Several studies were conducted to determine QoL in ITx patients, with differences in the samples and instruments used to assess it. Patients evaluated for ITx had lower QoL than those on HPN without complications. QoL seems to improve in most psychological, emotional and social areas after a successful ITx, a trend that seems to increase over time. These results would support the rehabilitative role of ITx for patients with irreversible CIF and impossibility to continue receiving HPN. SUMMARY: Although QoL after ITx patients improved over time compared with life on HPN, the heterogeneity in the samples included in several studies, and the lack of validated assessment tools, hinder the possibility to draw conclusions about improvement of QoL after ITx.

Postsurgical Intestinal Rehabilitation Using Semisynthetic Glucagon-Like Peptide-2 Analogue (sGLP-2) at a Referral Center: Can Patients Achieve Parenteral Nutrition and sGLP-2 Independency?

BACKGROUND: Teduglutide, a semisynthetic analogue of glucagon-like peptide-2 (sGLP-2), increases intestinal absorption of fluids and nutrients, reducing the need for parenteral nutrition (PN). This report aims to describe our experience with sGLP-2 in a cohort of adult patients with short-bowel syndrome. METHODS: This is a prospective observational study on adult patients initially evaluated in our specialized intestinal rehabilitation program that received sGLP-2 from June 2014 to March 2020. RESULTS: Autologous gastrointestinal reconstruction surgery (AGIRS) was performed in 108 patients; 68.5% (74 of 108) achieved intestinal sufficiency with standard medical therapy. Seventeen patients were treated with sGLP-2; 66.5% (8 of 12) received treatment for a mean time of 25.8 weeks (3.4-54.0) and could suspend PN. One patient reinitiated treatment due to renal lithiasis and acute renal failure. Currently, 7 of 12 patients (53.8%) continue without PN for a mean time of 165.6 weeks. Volume, energy, and days of PN were reduced in all patients. No serious adverse events were registered. Four of 7 patients (57.1%) who discontinued PN could also discontinue sGLP-2. Therefore, the use of sGLP-2 increased the overall success rate of PN independency after AGIRS to 76% (82 of 108). CONCLUSION: This study confirmed that sGLP-2 should be considered as part of the standard therapy for postsurgical medical rehabilitation treatment in patients with chronic intestinal failure. We add to the current knowledge that some patients can discontinue both PN and sGLP-2 in the long term, achieving complete recovery of their quality of life.

A 21 m Operation Range RFID Tag for "Pick to Light" Applications with a Photovoltaic Harvester.

In this paper, a novel Radio-Frequency Identification (RFID) tag for "pick to light" applications is presented. The proposed tag architecture shows the implementation of a novel voltage limiter and a supply voltage (VDD) monitoring circuit to guarantee a correct operation between the tag and the reader for the "pick to light" application. The feasibility to power the tag with different photovoltaic cells is also analyzed, showing the influence of the illuminance level (lx), type of source light (fluorescent, LED or halogen) and type of photovoltaic cell (photodiode or solar cell) on the amount of harvested energy. Measurements show that the photodiodes present a power per unit package area for low illuminance levels (500 lx) of around 0.08 µW/mm2, which is slightly higher than the measured one for a solar cell of 0.06 µW/mm2. However, solar cells present a more compact design for the same absolute harvested power due to the large number of required photodiodes in parallel. Finally, an RFID tag prototype for "pick to light" applications is implemented, showing an operation range of 3.7 m in fully passive mode. This operation range can be significantly increased to 21 m when the tag is powered by a solar cell with an illuminance level as low as 100 lx and a halogen bulb as source light.

Results of Surgical and Medical Rehabilitation for Adult Patients With Type III Intestinal Failure in a Comprehensive Unit Today: Building a New Model to Predict Parenteral Nutrition Independency.

BACKGROUND: Short-bowel syndrome remains the primary cause of intestinal failure (IF) in adult patients. We aim to report the long-term results of medical and surgical rehabilitation in a cohort of patients with type III IF (III-IF) and develop a formula to predict parenteral nutrition (PN) independency. METHODS: We used a retrospective analysis of a prospective database for III-IF patients undergoing autologous gastrointestinal reconstruction surgery (AGIRS) from March 2006 to August 2018. Analyzed variables included demographic data, postsurgical intestinal length (PSIL), postsurgical anatomy, teduglutide (TED) treatment, and PN volume reduction. Univariate analysis, Cox regression, logistic regression forward stepwise models, and receiver operating characteristic (ROC) curve were done using SPSS v20. RESULTS: AGIRS was performed in 88 patients. The most frequent anatomy at first visit was type 1. Prevailing anatomy after surgery was type 3. Eight patients started TED; 6 achieved freedom from PN. At a mean follow-up time of 1606.1 ± 1190.25 days, freedom from PN survival was achieved in 83%. Variables identified at the logistic regression analysis led to a novel formula to predict intestinal rehabilitation, including PSIL, presence of ileocecal valve, and use of TED as part of postsurgical treatment. CONCLUSIONS: AGIRS in this group of patients enabled intestinal length increase and also intestinal anatomy conversion into a more favorable type for intestinal rehabilitation. TED treatment was useful to discontinue PN in patients with classical negative anatomical predictors. The novel predicting formula has an ROC area under the curve = 0.82. Further studies are necessary to validate this formula.

0.5 V and 0.43 pJ/bit Capacitive Sensor Interface for Passive Wireless Sensor Systems.

This paper presents an ultra low-power and low-voltage pulse-width modulation based ratiometric capacitive sensor interface. The interface was designed and fabricated in a standard 90 nm CMOS 1P9M technology. The measurements show an effective resolution of 10 bits using 0.5 V of supply voltage. The active occupied area is only 0.0045 mm2 and the Figure of Merit (FOM), which takes into account the energy required per conversion bit, is 0.43 pJ/bit. Furthermore, the results show low sensitivity to PVT variations due to the proposed ratiometric architecture. In addition, the sensor interface was connected to a commercial pressure transducer and the measurements of the resulting complete pressure sensor show a FOM of 0.226 pJ/bit with an effective linear resolution of 7.64 bits. The results validate the use of the proposed interface as part of a pressure sensor, and its low-power and low-voltage characteristics make it suitable for wireless sensor networks and low power consumer electronics.

Avances en Gastroenterología Trasplante intestinal desde la clínica a la investigación traslacional: contribuciones de una unidad integral de insuficiencia intestinal, rehabilitación y trasplante. Seguimiento biomédico del proceso de trasplante intestinal y su correlación con los distintos eventos fisiopatológicos que atraviesa el paciente.

One of the greatest achievements in gastroenterology and surgery of the last 50 years has been the capability to transplant different abdominal organs of the digestive system separately or as a whole. The complexity of the intestinal transplantation demands a multidisciplinary team engaged in the management of patients with intestinal failure responsible for defining the need for nutritional support, rehabilitation, or intestinal transplantation. This team should include a basic research area to provide answers to unresolved clinical problems. The aim of this work is to update the current status of intestinal transplantation, and to show the progress and results of our center; emphasizing our achievements in the clinical area, and the contributions of the translational research and mucosal immunology studies as part of the integral unit of intestinal failure, rehabilitation and transplantation. The data reported here demonstrate that the intestinal transplantation has been established as a therapeutic option in our country and Latin America, with long term results that have ranked our service at the level of the best centers in the world positioning us as referent in the specialty.

Immunosuppressive therapies after intestinal transplant modulate the expression of Th1 signature genes during acute cellular rejection. Implications in the search for rejection biomarkers.

BACKGROUND AND AIMS: Acute cellular rejection (ACR) and infections are leading causes of graft loss and death in intestinal transplant patients. Our aim was to evaluate the impact of maintenance immunosuppressive therapies on the expression of pro-inflammatory mediators in small bowel at ACR diagnosis. MATERIALS AND METHODS: We analyzed expression levels of Th1-associated genes, IFNG, CXCL10, and CXCL11 by qPCR in 46 selected graft biopsies unequivocally assigned to mild ACR (n = 14) or normal histopathology and clinical condition (n = 32) from 15 patients receiving two different immunosuppressive (IS) schemes. Double treatment: corticosteroids and tacrolimus (n = 17) and triple treatment: sirolimus or mycophenolate mofetil in addition to the basal therapy (n = 29). RESULTS: IFNG, CXCL10, and CXCL11 were induced during rejection (p < 0.05; p < 0.005, and p < 0.05, respectively). However, when rejection and control groups were classified according to immunosuppressive treatment, in the rejection group, significant differences of IFNG, CXCL10, and CXCL11 expression (p < 0.001; p < 0.005, and 0.01, respectively) were detected, whereas no differences were observed in the control group. CONCLUSION: Gene expression of Th1 response mediators is higher during ACR. Triple IS group showed significantly lower expression of pro-inflammatory Th1 mediators during mild ACR indicating that use of these markers to monitor rejection can be affected by the IS treatment used.

Serum albumin level during intestinal exfoliative rejection: a potential predictor of graft recovery and patient outcome.

Exfoliative rejection is a severe complication after intestinal transplant. The assessment of mucosa histology is restricted to the area reached by endoscopy. We aim to evaluate the serum albumin (SA) value as a parameter of graft damage and clinical prognosis in intestinal exfoliative rejection (ExR). The present study is a retrospective analysis of 11 episodes of ExR occurred in a cohort of 26 patients. SA levels were measured 24 h after diagnosis and twice a week thereafter and then correlated with parameters of clinical and graft histological recovery (HR). During ExR, all patients had very low SA levels, reaching a minimum average of 1.9 ± 0.3 g/dL. According to the value of albumin levels at ExR diagnosis, the patients were grouped finding a correlation with their clinical evolution. Six ExR episodes presented with severe hipoalbuminemia (<2.2 g/dL; p < 0.05) that correlated with worse patient and graft outcome, ranging from graft loss and need for re-transplantation to delayed clinical and HR. SA at ExR diagnosis may be an indicator of the severity of the ExR process, and it could also be used as an early predictor of patient and graft outcome.

Visceral Kaposi's sarcoma remission after intestinal transplant. First case report and systematic literature review.

BACKGROUND: Kaposi's sarcoma (KS) is an infrequent vascular neoplasm commonly diagnosed as an isolated cutaneous lesion that can involve other organs. So far, there are no data in the literature about the development of KS after intestinal transplant. METHODS: In this study, the authors describe a case of "visceral KS" with pulmonary and intestinal involvement and perform a systematic literature review of case reports and single-center series identified in MEDLINE. RESULTS: This case was a 42-year-old man, diagnosed with visceral KS 9 months after receiving an isolated intestinal transplant. He was successfully treated with a combination of sirolimus and liposomal doxorubicin and achieved an 18-month disease-free survival. A total of 54 cases from 27 manuscripts and the present case were analyzed in this study. The mean time from transplant to diagnosis was 17.2 months. Lungs and gastrointestinal tract were the main organs involved. Immunosuppressants were discontinued in two of the three (66.7%) cases, and sirolimus was added in eight cases. Doxorubicin was used in 12 cases. In a univariate analysis, the use of Tacrolimus, type of transplant, and presence of cutaneous KS seem to be the significant predictors of response to therapy and survival; the addition of doxorubicin showed a reduction in graft loss. CONCLUSIONS: Treatment of KS in posttransplant patients should be designed aiming to obtain a complete response, irrespective of the organ affected. Only recipients who are able to achieve a sustained response would be able to obtain long-term disease-free survival.

Evaluation of a noninvasive method for cardiac output measurement in critical care patients.

OBJECTIVE: Thermodilution (TD) is the gold standard to monitor cardiac output (CO) in critical care. However, there is concern about the safety of right-ventricular catheterization. The CO(2) rebreathing technique allows noninvasive CO determination by means of the indirect Fick principle. Our objectives were: (a) to assess the accuracy of a new system of CO measurement using the CO(2) partial rebreathing method (PRCO); (b) to evaluate whether the PRCO itself may induce changes in CO. DESIGN AND SETTING: Prospective study in the intensive care department in a university-affiliated hospital. PATIENTS: Twenty-two mechanically ventilated critically ill patients. INTERVENTIONS: CO measured simultaneously by PRCO and TDCO. MEASUREMENTS AND RESULTS: PRCO and TDCO values were compared by concordance analysis. Stability of cardiac output during PRCO was evaluated by comparing the TDCO measurements before, during, and after the partial rebreathing period using analysis of variance. From a total of 79 valid sets of measurements, bias and precision was calculated at -0.18+/-1.39 l/min. The concordance analysis of lower and intermediate CO values (<7 l/min) yielded a bias and precision calculation of -0.07+/-0.91 l/min. No changes in hemodynamics were observed during the partial rebreathing period. CONCLUSIONS: The noninvasive partial CO(2) rebreathing technique may be an alternative method for CO determination in mechanically ventilated critically ill patients. The rebreathing maneuver alone does not induce changes in CO.