Meta-analysis of the prognostic role of perioperative platelet count in posthepatectomy liver failure and mortality.

BACKGROUND: Emerging evidence suggests that the perioperative platelet count (PLT) can predict posthepatectomy liver failure (PHLF). In this systematic review and meta-analysis, the impact of perioperative PLT on PHLF and mortality was evaluated. METHODS: MEDLINE and Web of Science databases were searched systematically for relevant literature up to January 2018. All studies comparing PHLF or mortality in patients with a low versus high perioperative PLT were included. Study quality was assessed using methodological index for non-randomized studies (MINORS) criteria. Meta-analyses were performed using Mantel-Haenszel tests with a random-effects model, and presented as odds ratios (ORs) with 95 per cent confidence intervals. RESULTS: Thirteen studies containing 5260 patients were included in the meta-analysis. Two different cut-off values for PLT were used: 150 and 100/nl. Patients with a perioperative PLT below 150/nl had higher PHLF (4 studies, 817 patients; OR 4·79, 95 per cent c.i. 2·89 to 7·94) and mortality (4 studies, 3307 patients; OR 3·78, 1·48 to 9·62) rates than patients with a perioperative PLT of 150/nl or more. Similarly, patients with a PLT below 100/nl had a significantly higher risk of PHLF (4 studies, 949 patients; OR 4·65, 2·60 to 8·31) and higher mortality rates (7 studies, 3487 patients; OR 6·35, 2·99 to 13·47) than patients with a PLT of 100/nl or greater. CONCLUSION: A low perioperative PLT correlates with higher PHLF and mortality rates after hepatectomy.

Analysis of the biliostatic potential of two sealants in a standardized porcine model of liver resection.

BACKGROUND: Improved resection techniques has decreased mortality rate following liver resections(LRx). Sealants are known as effective adjuncts for haemostasis after LRx. We compared biliostatic effectiveness of two sealants in a standardized porcine model of LRx. MATERIAL AND METHODS: We accomplished left hemihepatectomy on 27 pigs. The animals were randomized in control group(n = 9) with no sealant and treatment groups (each n = 9), in which resection surfaces were covered with TachoSil® and TissuFleece®/Tissucol Duo®. After 5 days the volume of ascites(ml), bilioma and/or bile leakages and degree of intra-abdominal adhesions were analysed. RESULTS: Proportion of ascites was lower in TissuFleece/Tissucol Duo® group. The ascites volume was lower in TachoSil® group. In sealant groups, increased adhesion specially in the TachoSil® group was seen. A reduction of the "bilioma rate" was seen in sealant groups, which was significantly lower in TissuFleece®/Tissucol Duo® group. CONCLUSION: In a standardized condition sealants have a good biliostatic effect but with heterogeneous potentials. This property in combination with the cost-benefit analysis should be the focus of future prospective studies.

Modified Spiral Intestinal Lengthening and Tailoring for Short Bowel Syndrome.

BACKGROUND: The spiral intestinal lengthening and tailoring (SILT) procedure is a new surgical technique for autologous intestinal reconstruction in patients with short bowel syndrome. The aim of this work is to present a first description of a modified SILT technique by which the mucosal layer is left intact to possibly reduce the severe postoperative complications of intestinal leakage and abdominal abscess formation. MATERIALS AND METHODS: The modified SILT technique was performed on a 10-cm-long intestinal segment in 2 pigs to determine the technical feasibility. Thereafter, the short-term clinical feasibility was monitored clinically in 2 dogs by gastrointestinal X-ray series at postoperative day 4 and by relaparotomy postoperative day 10. RESULTS: It was technically feasible to lengthen the intestinal segment from 10 cm to 20 cm and tailoring it from 3 cm to 1.7 cm in diameter, while leaving the intestinal mucosal layer intact. The postoperative course was uneventful for both dogs. The gastrointestinal X-ray series showed an inconspicuous intestinal transit time without any signs of stricture, perforation, or leakage. In the relaparotomy, the initially achieved lengthening and tailoring extents were preserved and the operated intestinal segment was well perfused with no early signs of necrosis, stenosis, or leakage. CONCLUSIONS: Leaving the mucosal layer intact during SILT is technically and clinically feasible in the short term in a large animal model. Further studies are needed to fully assess the impact of this technical modification on the long-term outcome of larger series.

Comparison of the laparoscopic versus open live donor nephrectomy: an overview of surgical complications and outcome.

BACKGROUND: Kidney transplantation (KTx) is considered to be the treatment of choice for end stage renal disease. One of the most challenging dilemmas in KTx is the shortage of suitable organs. The live donor nephrectomy is considered a unique operation performed on healthy donors, which provides a superior outcome in the recipients. Several surgical techniques have been developed so far to minimize donor postoperative complications as much as possible without compromising the quality of the kidney. The development of a minimally invasive surgery, laparoscopic live donor nephrectomy (LDN), was based on this concept. MATERIALS AND METHODS: By searching the pubmed, we reviewed the most evidence based clinical studies specifically randomized clinical trials and meta-analyses to give an overview of the efficacy and safety of LDN versus ODN. RESULTS: The advantages of a LDN vs. a conventional open donor nephrectomy (ODN) are a smaller incision, better wound cosmetics, a lower rate of incisional hernia and adhesion, less postoperative pain, shorter hospitalization, and earlier return to work. Some concerns are longer operative and warm ischemic times, long-term learning curve for surgeons, and the risk of more serious complications than during an ODN. CONCLUSION: Overall, the review of literature shows that a LDN provides less postoperative pain, a shorter hospital stay, a shorter period of rehabilitation, and earlier return to normal work and physical activities in comparison to the conventional open flank nephrectomy but is comparable to the mini muscle splitting approach. The complication rate is generally lower in centers accustomed to performing LDNs; however, complications can be life threatening and could impose significant costs to the health system. Weighing the longer operation and warm ischemic time, as well as the risk of more serious complications against the advantages of a LDN mandates a precise indication. The risk-benefit assessment for choosing one procedure should be done meticulously. Even though the short-term graft function in both techniques is comparable, there is a lack of enough long-term outcome analyses. Finally, in any transplant center, the cost of the laparoscopic procedure should be considered.

Comparison of two different transection techniques in liver surgery-an experimental study in a porcine model.

AIMS: Postoperative morbidity and mortality after liver resection is closely related to the degree of intraoperative blood loss; the majority of which occurs during transection of the liver parenchyma. Many approaches and devices have therefore been developed to limit bleeding, but none has yet achieved perfect results up to now. The aim of this standardized chronic animal study was to compare the safety and efficacy of the LigaSure™ Vessel Sealing System (LVSS) with the stapler technique, which is one of the modern techniques for transecting the parenchyma in liver surgery. METHODS: Sixteen pigs underwent a left liver resection (LLR). Eight pigs received a LLR by means of an Endo GIA, whereas the other eight pigs underwent liver parenchymal transection followed by simultaneous sealing by the LVSS. The operating time, transection time, blood loss during transection, and time of hemostasis were measured on the day of LLR (postoperative day 0/POD 0). Animals were re-explored on postoperative day 7 (POD 7) and the transection surface of remnant liver was observed for fluid collection (hematoma, biloma, and abscess), necrosis, and other pathologies. A biopsy was taken from the area of transection for histopathological examination. RESULTS: All animals survived until POD 7. Operating time and transection time of the liver parenchyma on POD 0 was significantly shorter in the stapler group. There was no significant difference between the two groups in terms of blood loss during transection, time of hemostasis and number of sutures for hemostasis on POD 0, morbidity rate, as well as the histopathological examination on POD 7. Furthermore, the material costs were significantly higher in the stapler group than in the LVSS group. CONCLUSION: In this standardized chronic animal study concerning transection of the parenchyma in liver surgery, LVSS seems not only to be safe, but also comparable with the stapler technique in terms of morbidity and mortality. Additionally, LVSS significantly reduces material costs. However, the transection time is significantly longer for LVSS than for the stapler resection technique.

Pig kidney transplantation: an up-to-date guideline.

BACKGROUND: Swine and human beings have many aspects in common that make swine a well-characterized large animal model for kidney transplantation (KTx). However, pigs have some peculiar anatomical characteristics that standardized techniques must adapt to. The aim of this study was to prepare an up-to-date guideline for porcine KTx. METHODS: To achieve this goal, we performed a Medline search using the terminology 'kidney' or 'renal' and 'transplantation' and 'pig' or 'swine' or 'porcine'. We found over 1,300 published articles since 1963. Only 13 studies focused on the surgical aspect. Furthermore, we reviewed related books and articles about swine anatomical characteristics and surgery. Finally, our experimental experiences of KTx during the last few decades were added to this collection. RESULTS: Proper hosting, fasting, anesthesia, medical therapy and monitoring can prevent postoperative complications. Explantation with a Carrel patch of the aorta facilitates the implantation and prevents future stenosis. Native nephrectomy makes the follow-up of the implanted organ more precise. KTx in the infrarenal fossa via end-to-side anastomosis to the aorta and inferior vena cava followed by ureteroureterostomy are the recommended options for KTx in pigs compared to other possible methods. CONCLUSION: Pigs, with respect to their characterizations, constitute one of the best large animal models for KTx. Preoperative preparations are as important as the intra- and postoperative management. Using the most adaptable methods of surgery with respect to the specific anatomical characteristics of pigs can prevent undermining the studies and avoid preventable complications and pitfalls.

Current practice and future perspectives in the treatment of short bowel syndrome in children--a systematic review.

PURPOSE: Short bowel syndrome (SBS) is a malabsorption disorder of the intestine, which leads to an inadequate alimentary supply. A number of therapeutic approaches are already in use, but research advances may provide new options in the future. The purpose of this paper was to provide an overview of the established therapeutic approaches together with a discussion of the future perspectives in the treatment of patients with SBS. We review those studies dealing with the treatment of SBS patients and discuss both surgical and non-surgical approaches together with tissue engineering. METHODS: A systemic review of Medline-cited studies dealing with current practice and future perspectives in the treatment of short bowel in children was performed. RESULTS: Surgical approaches, non-surgical approaches, and tissue engineering which was used in the treatment of SBS were analyzed. Among the surgical approaches, the bowel lengthening procedures and small bowel transplantation are prevalent. Stimulants are most important concerning non-surgical approaches. Tissue engineering seems to be more experimental and was also evaluated. CONCLUSION: The treatment of SBS patients remains very complex. It is eminent to find the best therapeutic option for each patient and to individualize and modify the different possible types of applied techniques frequently.

[Living-donor kidney transplantation]. / Lebendspende-Nierentransplantation.

Due to the existing organ shortage the option of a kidney transplantation (KTx) in patients with end-stage renal disease is not always possible despite the offer of this therapy. So far the required number of KTx could not be adequately achieved by organ donations from deceased persons. To solve this problem living donation KTx programs have already become established in many transplantation centers. In published reports it has been shown that with the living donation program better results could be achieved in terms of graft function and patient survival compared to cadaver donation KTx. Therefore, living donation KTx allows an optimal alternative to expand the organ pool. The aim of our study is to present the long-term results of our living donation KTx program regarding graft function and patient survival. Finally, the risks of living donation KTx will be discussed based on the reported experiences of other centers.

The role of an interdisciplinary transplant team on living donation kidney transplantation program.

During the last decades, the disparity between the organ supply and the demand for kidney transplantation in Europe has led to consider living donors as a more acceptable option. In the last 7 years, we have established an interdisciplinary supporting transplant team to increase the rate of living donation. After 2001, the new interdisciplinary transplant team consisted of a transplant surgeon, a nephrologist, a pediatrician, a radiologist, a psychologist, a transplant coordinator, and a transplant nurse. We performed a prospective analysis to examine the effect of implementing this team on our living donation program. Demographic data, the annual number of procedures, the duration of waiting, and the cold ischemia time were evaluated among brain-dead and living donors. From January 2002 until December 2008, the number of patients who were annually on the waiting list increased 42% (from 377 to 536 patients). Consequently, the number of the total kidney transplants increased from 81 to 120 with an annual median of 98 cases. By implementing the interdisciplinary transplant team, a significant increase of living kidney donors was observed: from 18 to 42 cases; median = 27). In the last 7 years, a total number of 796 kidney transplants have been performed: 567 from brain-dead and 229 from living donors. In 2001, the waiting list times for recipients who received grafts from brain-dead versus living donors were 1356 versus 615 days respectively. Compared with 2008, the duration on the waiting list decreased significantly for patients receiving a living donor graft, whereas there was a slight increase for the patients in the brain-dead group: brain death versus living donors: 1407 versus 305 days. The interdisciplinary approach has also reduced the cold ischemia time for the living donor recipients: 3 hours and 42 minutes in 2001 versus 2 hours and 50 minutes in 2008. During the last years, by implementing an interdisciplinary transplant team, supporting living donor procedures has produce a gradual increase in the number of kidney transplants from living donors with a remarkable decrease in waiting and cold ischemia times, the latter presumably influencing graft quality.

Interventional radiologic procedures in the treatment of complications after liver transplantation.

The aim of this study is to report our interventional radiologic procedures (IRP) in liver transplant (LTX) patients. These include procedures for biliary, arterial, venous, and portal complications, as well as the treatment of infected and non-infected fluid collections. This retrospective study covered 583 patients (mean age: 44 +/- 14 yr) in whom a total of 685 LTX were performed from August 1987 to April 2005. Overall, 182 LTX patients underwent a total of 428 IRP, including digital subtraction angiography (n = 152/35.51%), percutaneous transluminal angioplasty (PTA) (n = 4/0.93%) and PTA + stent (n = 7/1.63%) of arterial anastomosis, PTA + stent of the celiac trunk (n = 2/0.46%), transjugular intrahepatic portosystemic shunt (TIPS) (n = 2/0.46%), arterial lysis (n = 4/0.93%), venous lysis (n = 2/0.46%), inferior vena cava stenting (n = 2/0.46%), percutaneous biliary drainage (n = 34/7.94%), percutaneous transluminal dilatation (PTD) of the choledocho-enteric anastomosis (n = 16/3.73%), biliary stent (n = 5/1.16%), intrahepatic biliary flushing treatment, stone and cast biliary extraction (n = 27/6.30%), other interventions (e.g., embolization in other regions, transjugular liver biopsies, lymphangiographies) (n = 9/2.10%), and ultrasound- and computer tomography-guided biopsies and percutaneous drainage (n = 153/35.74%). The overall success rate was 85.7%. Technical improvements in LTX and interventional radiology permit vascular and biliary complications to be treated successfully by interventional radiology.

A single center experience of combined liver kidney transplantation.

With advancements in the operative techniques, patient survival following liver transplantation (LTx) has increased substantially. This has led to the acceleration of pre-existing kidney disease because of immunosuppressive nephrotoxicity making additional kidney transplantation (KTx) inevitable. On the other hand, in a growing number of patients on the waiting list to receive liver, long waiting time has resulted in adverse effect of decompensated liver on the kidney function. During the last two decades, the transplant community has considered combined liver kidney transplantation (CLKTx) to overcome this problem. The aim of our study is to present an overview of our experience as well as a review of the literature in CLKTx and to discuss the controversy in this regard. All performed CLKTx (n = 22) at our institution as well as all available reported case series focusing on CLKTx are extracted. The references of the manuscripts were cross-checked to implement further articles into the review. The analyzed parameters include demographic data, indication for LTx and KTx, duration on the waiting list, Model for End-Stage Liver Disease (MELD) score, Child-Turcotte-Pugh (CTP) score, immunosuppressive regimen, post-transplant complications, graft and patient survival, and cause of death. From 1988 to 2009, a total of 22 CLKTx were performed at our institution. The median age of the patients at the time of CLKTx was 44.8 (range: 4.5-58.3 yr). The indications for LTx were liver cirrhosis, hyperoxaluria type 1, polycystic liver disease, primary or secondary sclerosing cholangitis, malignant hepatic epithelioid hemangioendothelioma, cystinosis, and congenital biliary fibrosis. The KTx indications were end-stage renal disease of various causes, hyperoxaluria type 1, polycystic kidney disease, and cystinosis. The mean follow-up duration for CLKTx patients were 4.6 +/- 3.5 yr (range: 0.5-12 yr). Overall, the most important encountered complications were sepsis (n = 8), liver failure leading to retransplantation (n = 4), liver rejection (n = 3), and kidney rejection (n = 1). The overall patient survival rate was 80%. Review of the literature showed that from 1984 to 2008, 3536 CLKTx cases were reported. The main indications for CLKTx were oxalosis of both organs, liver cirrhosis and chronic renal failure, polycystic liver and kidney disease, and liver cirrhosis along with hepatorenal syndrome (HRS). The most common encountered complications following CLKTx were infection, bleeding, biliary complications, retransplantation of the liver, acute hepatic artery thrombosis, and retransplantation of the kidney. From the available data regarding the need for post-operative dialysis (n = 673), a total of 175 recipients (26%) required hemodialysis. During the follow-up period, 154 episodes of liver rejection (4.3%) and 113 episodes of kidney rejection (3.2%) occurred. The cumulative 1, 2, 3, and 5 yr survival of both organs were 78.2%, 74.4%, 62.4%, and 60.9%, respectively. Additionally, the cumulative 1, 2, 3, and 5 yr patient survival were 84.9%, 52.8%, 45.4%, and 42.6%, respectively. The total number of reported deaths was 181 of 2808 cases (6.4%), from them the cause of death in 99 (55%) cases was sepsis. It can be concluded that there is still no definitive evidence of better graft and patient survival in CLKTx recipients when compared with LTx alone because of the complexity of the exact definition of irreversible kidney function in LTx candidates. Additionally, CLKTx is better to be performed earlier than isolated LTx and KTx leading to the avoidance of deterioration of clinical status, high rate of graft loss, and mortality. Shorter graft ischemia time and more effective immunosuppressive regimens can reduce the incidence of graft malfunctioning in CLKTx patients. Providing a model to reliably determine the need for CLKTx seems necessary. Such a model can be shaped based upon new and precise markers of renal function, and modification of MELD system.

Evaluation of the combined laparoscopic and mediastinoscopic esophagectomy technique.

BACKGROUND: Laparoscopic esophagectomy is technically difficult especially during dissection in the upper mediastinum. This limitation may be surpassed with the help of mediastinoscopy or of the recently introduced robotic surgical systems. The aim of the present study was to evaluate in an experimental porcine model the feasibility of the combined laparoscopic and mediastinoscopic transhiatal esophagectomy technique and to compare it with the robotic-assisted transhiatal and conventional approaches. MATERIALS AND METHODS: Transhiatal esophagectomy was performed in Landrace pigs under general anesthesia using three different techniques: Group A (n = 9): combined laparoscopic and mediastinoscopic, group B (n = 4): robotic-assisted and group C (n = 8): conventional "open". The feasibility, difficulty and accuracy of the procedure along with operative time, blood loss, intraoperative incidents and overall satisfaction of the surgical team were assessed for each technique. RESULTS: Operations in group A were feasible and reproducible. Although the procedure was technically difficult, the constant view on the operative field was highly appreciated by the operative team and facilitated an accurate and safe dissection. The main intraoperative complications were related to the side-effects of tension pneumothorax accompanying pleural injuries. In group B the features of the robotic system reduced the difficulty of dissection and obviated the need for mediastinoscopy. Operations in group C were quick and almost incident-free, facilitated also by the particularities of the animal model that could not reproduce identically the clinical situation. CONCLUSIONS: The combined laparoscopic and mediastinoscopic esophagectomy technique is feasible and offers certain advantages over the open approach while the robotic-assisted approach is an emerging less difficult alternative. Further studies are required to establish whether the advantages of minimally-invasive approach compensate for the increased technical difficulty and prolonged operative time.

Current concepts in transplant surgery: liver transplantation today.

INTRODUCTION: The discipline of liver transplantation (LTx) has been developed over the past decades, and LTx is now considered the gold standard for the treatment of patients with end-stage liver diseases and early liver tumors in cirrhotic livers. This procedure is now performed routinely in many transplant centers, and it has provided an enormous technical innovation to the field of hepatobiliary surgery. Allocation decision of liver organs is based on medical need and timing. MATERIALS AND METHODS: The Mayo Model for End Stage Liver Disease based on patient-specific criteria was developed and applied to prioritize patients on the waiting list. From the donor aspects of LTx, sources of organ, excluding xenotransplantation, can be brain-dead donors, living donors, and non-heart-beating donors. Today, the majority of livers are procured from cadaveric donors. In addition to the conventional LTx, other types are living-donor LTx, reuse of grafts as domino transplantation, ex situ as well as in situ split LTx, and reduced-size LTx. The transplantation procedure consists of several steps including donor selection and management, liver procurement and preservation, back-table preparation, recipient operation with liver implantation, postoperative care, immunosuppression, and follow-up. RESULTS: The postoperative complications are divided into surgical, non-surgical, and multifactorial complications. Surgical complications account about 34% of morbidities after LTx and are mainly categorized to vascular and biliary complications. The main medical ones are non-surgical bleeding and infections. The multifactorial complications include primary non- or poor function and small-for-size syndrome. The pretransplant outcome predictors of LTx can be divided into donor, recipient, operative, and postoperative factors. CONCLUSION: LTx is now considered a safe and standardized procedure with a substantially improved graft and patient survival and acceptable morbidity rates. However, the new problems, including recurrence of hepatitis C or hepatocellular carcinoma, chronic biliary complications, opportunistic infections, and development of de-novo malignancies are the major problems affecting the long-term outcome of transplanted patients.

The role and value of sirolimus administration in kidney and liver transplantation.

Enormous advancements in visceral transplantation have led to significant improvements in the quality of life of patients. However, despite these developments, the average graft half-life after transplantation has remained almost unchanged and chronic rejection is still considered a major problem. In this regard, more concerns have shifted to factors influencing long-term graft survival, patient survival, and quality of life. To achieve this goal, detrimental effects of immunosuppressive (IS) agents, which have deleterious influence on the quality of life and/or patient survival, should be reduced. In the course of recent years, the transplant community has worked on reducing these side effects by developing new ISs, employing new combination regimens, or finding and adjusting optimal dosages and blood level concentrations. Among the IS agents, the antifungal, antitumoral and IS activity of mammalian target of rapamycin (mTOR) inhibitors without nephrotoxicity, have received special attention regarding this new class of IS. Sirolimus (SRL), as the first member of mTOR inhibitors, has been utilized in many clinical trials with respect to its benefit-risk assessment. In our review, the clinical evolution of SRL, as well as the evidence-based clinical benefits of SRL in kidney and liver transplantation (KTx, LTx), are summarized. Various studies of SRL in KTx and LTx have shown that combination therapy with SRL will enrich the variety of IS modalities. It also can be regarded as a safe base therapy to which other necessary drugs can be added. In addition to the enhanced acute rejection prophylaxis, and in contrast to the calcineurin inhibitors (CNI) and steroids, this drug solely does not have common side effects such as nephrotoxicity, neurotoxicity, diabetes mellitus and hypertension. Moreover, this agent might diminish vasculopathic processes that mediate chronic allograft nephropathy (CAN). Therefore, by reducing the likelihood of CAN it can decrease the rate of long-term organ failure. One possibly desirable characteristic of SRL is its antiproliferative effect, which could provoke antitumoral or antiatherogenic activity following transplantation. Despite all promising impacts of SRL in organ transplantation, there are some concerns regarding the adverse effects of this drug, for instance dyslipidemia, pneumonitis and wound healing problems. However, the majority of these side effects can be reduced or ceased by careful dose adjustments and correct timing of use. In conclusion, after a decade of both in vivo and in vitro studies on SRL, it can be advocated that SRL is a promising, potent and effective IS agent as it reduces the rate of acute rejection episodes in de novo transplants. It could improve the quality of life, graft and patient survival rate, and achieve excellent outcomes with few adverse effects when wisely used in combination with other immunosuppressants.

Wound complications following kidney and liver transplantation.

Advances in surgical techniques and immunosuppression (IS) have led to an appreciable reduction in postoperative complications following transplantation. However, wound complications as probably the most common type of post-transplantation surgical complication can still limit these improved outcomes and result in prolonged hospitalization, hospital readmission, and reoperation, consequently increasing overall transplant cost. Our aim was to review the literature to delineate the evidence-based risk factors for wound complications following kidney and liver transplantation (KTx, LTx), and to present the preventive and therapeutic modalities for this bothersome morbidity. Generally, wound complications are categorized as superficial and deep wound dehiscences, perigraft fluid collections and seroma, superficial and deep wound infections, cellulitis, lymphocele and wound drainage. The results of several studies showed that the most important risk factors for wound complications are IS and obesity. Additionally, there are surgical and/or technical factors, including type of incision, reoperation, and surgeon's expertise, as well as comorbidities such as advanced age, diabetes mellitus, malnutrition, and uremia. Preventive management of wound complications necessitates defining their etiological factors so that their detrimental effects on healing processes can be addressed and reduced. IS modalities and agents, especially sirolimus (SRL), and steroids (ST) should be adjusted according to the patient's co-existing risk factors. SRL should be administered three months after transplantation and ST should be tapered as soon as possible. A body mass index (BMI) lower than 30 kg/m2 is advisable for inclusion in a transplantation program, but higher BMIs do not exclude recipients. Surgical risk factors can be prevented by applying precise surgical techniques. Therapeutic modalities must focus on the most efficient and cost-effective medications and/or interventions to facilitate and improve wound healing.

Development and evaluation of a training module for the clinical introduction of the da Vinci robotic system in visceral and vascular surgery.

BACKGROUND: With the increasing use of the surgical robotic system in the clinical arena, appropriate training programs and assessment systems need to be established for mastery of this new technology. The authors aimed to design and evaluate a clinic-like training program for the clinical introduction of the da Vinci robotic system in visceral and vascular surgery. METHODS: Four trainees with different surgical levels of experience participated in this study using the da Vinci telemanipulator. Each participant started with an initial evaluation stage composed of standardized visceral and vascular operations (cholecystectomy, gastrotomy, anastomosis of the small intestine, and anastomosis of the aorta) in a porcine model. Then the participants went on to the training stage with the rat model, performing standardized visceral and vascular operations (gastrotomy, anastomosis of the large and small intestines, and anastomosis of the aorta) four times in four rats. The final evaluation stage was again identical to the initial stage. The operative times, the number of complications, and the performance quality of the participants were compared between the two evaluation stages to assess the impact of the training stage on the results. RESULTS: The operative times in the final evaluation stage were considerably shorter than in the initial evaluation stage and, except for cholecystectomies, all the differences reached statistical significance. Also, significantly fewer complications and improved quality for each operation in the final evaluation stage were documented, as compared with their counterparts in the initial evaluation stage. These improvements were recorded at each level of experience. CONCLUSIONS: The presented experimental small and large animal model is a standardized and reproducible training method for robotic surgery that allows evaluation of the surgical performance while shortening and optimizing the learning-curve.

Evaluation of microperfusion disturbances in the transplanted liver after Kupffer cell destruction using GdCl3: an experimental porcine study.

BACKGROUND: Organ function after liver transplantation is determined by ischemia-reperfusion injury. Destruction of Kupffer cells with gadolinium chloride (GdCl3) has been shown to have a possible preventive effect on the extent of this injury, which can be extrapolated by analyzing the distribution of hepatic microperfusion. The aim of this study was to evaluate the protective effect of GdCl3 on disturbances of microperfusion in the transplanted liver. METHODS: Landrace pigs were randomly divided into three groups. In the control group (CG; n=6) a mapping of the native liver was conducted. For mapping, the four hepatic liver lobes were named from right to left with A to D and every lobe was divided into three vertical segments (cranial, medial, and caudal). In each of these 12 areas, microperfusion was quantified using a thermodiffusion probe (TD [mL/100 g/min]). The other two groups were considered as transplanted treated group (TTG; n=10) and transplanted nontreated group (TnTG; n=10). The TTG received an infusion of 20 mg/kg GdCl3 intravenously 24 hours before organ harvesting. Then standardized orthotopic liver transplantation was performed. In TnTG, standardized orthotopic liver transplantation was carried out without prior GdCl3 injection. In the recipients, the microperfusion of transplanted livers were mapped in both TnTG and TTG, in two different time points (1 hour [n=5] and 24 hours (n=5]) after reperfusion. RESULTS: A significant reduction of macrophages in the TTG livers in comparison to the CG and TnTG livers was observed (P<.05). However, the number of macrophages in CG and TnTG livers showed no significant difference (P>.05). Regarding liver microperfusion, in TnTG, a marked heterogeneity was detected in the livers after reperfusion. Significant differences between liver lobes (horizontal planes; P=.032) and vertical layers of intralobar liver parenchyma (P=.029) were observed. The same pattern was seen in TTG livers after reperfusion and a significant difference between horizontal (P=.024) and vertical layers (P=.018) of liver tissue were observed. Comparing intralobar regional flow data between vertical planes 24 hours after reperfusion still showed a prominent variation of hepatic tissue perfusion in TnTG livers (P=.028). Within the same horizontal layers, no significant differences between lobes were measured anymore (P=.16). Contrary to TnTG, in TTG, a homogenous pattern of regional liver tissue perfusion was recorded 24 hours after reperfusion. Comparison of TD data on the liver regions showed no significant microperfusion differences in either horizontal (P=.888) or vertical (P=.841) layers. CONCLUSIONS: Application of GdCl3 resulted in a significant reduction of Kupffer cells. Twenty four hours after transplantation microperfusion showed a homogeneous pattern, which constituted an earlier and better recovery of the transplanted liver. Therefore, destruction of Kupffer cells reduced ischemia-reperfusion injury and seemed to be responsible for the early recovery of microperfusion disturbances and thus for an improvement of graft function.