Objective evaluation of minimally invasive surgical skills for transplantation. Surgeons using a virtual reality simulator.

BACKGROUND: The learning curve in laparoscopic surgery may be associated with higher patient risk, which is unacceptable in the setting of kidney donation. Virtual reality simulators may increase the safety and efficiency of training in laparoscopic surgery. The aim of this study was to investigate if the results of a training session reflect the actual skill level of transplantation surgeons and whether the simulator could differentiate laparoscopic experienced transplantation surgeon from advanced trainees. SUBJECTS AND METHODS: 16 subjects were assigned to one of two groups: 5 experienced transplantation surgeon and 11 advanced residents, with only assistant role during transplantation. The level of performance was measured by a relative scoring system that combines single parameters assessed by the computer. RESULTS: The higher the level of transplantation experience of a participant, the higher the laparoscopic performance. Experienced transplantation surgeons showed statistically significant better scores than the advanced group for time and precision parameters. CONCLUSIONS: Our results show that performance of the various tasks on the simulator corresponds to the respective level of experience in transplantation surgery in our research groups. This study confirms construct validity for the LapSim. It thus measures relevant skills and can be integrated in an endoscopic training and assessment curriculum for transplantations surgeons.

[Introduction of a critical incident reporting system in a surgical university clinic. What can be achieved in a short term?]. / Einführung eines Critical Incident Reporting System in einer chirurgischen Universitätsklinik: Was kann kurzfristig erreicht werden?

BACKGROUND AND OBJECTIVE: "Critical incident reporting systems" (CIRS) are voluntary systems which, within the framework of risk management, provide pointers to the type and origin of critical incidents (including "errors"). The interest in introducing a CIRS is great, but whether it can fulfill its promises remains to be clarified. The aim of this study was to answer the question of whether an CIRS in a structured form would be acceptable to staff and whether it would be suitable for introducing targeted measures for achieving improvements. METHODS: The introduction of a CIRS in the Department of Visceral, Thoracic and Vascular Surgery proceeded according to the recommendations of the Action Alliance for Patients' Safety (Aktionsbündnis für Patientensicherheit e.V.). RESULTS: During a period of 13 months we received a total of 96 reports, 29.3% from various levels of carers/nurses, while 35.4% were from doctors. 40.6% of the incidents had been observed by the reporting person, in 38.5% of cases the reporting person had been involved in the incident and in 12.5% this person had helped in dealing with the incident. 38.5% of the reported critical incidents occurred between 06.00 and 12.00, while 34.4% occurred between 12:00 and 18:00 o/c. In 32.3% of cases the estimated duration of dealing with the incident was under four hours and between four and eight hours in 26%. During the first year of this study 12 actions were started and continued in consequence of an analysis of the reported critical incidents. CONCLUSION: After one year of the study it was found that a CIRS can be reliably introduced into a surgical department in accordance with the recommendations of the Action Alliane for Patients' Safety. When introduced correctly CIRS provides valuable information, which will lead to risk reduction in surgery.

Intraoperative assessment of liver organ condition by the procurement surgeon.

UNLABELLED: Generally the transplanting surgeon accepts or declines the offer of a marginal organ in view of all available information. Hence, in some cases it is the procurement surgeon who decides about the suitability for potential further liver transplantation. METHODS: From January 1, 2003 to September 30, 2005, a total of 402 organ procurement operations were performed in our region. RESULTS: Due to infrastructural problems in nine cases intraoperative evaluation of liver biopsies was not achievable in time, and the decision to reject the organs was based on the procurement surgeon's clinical assessment. The main reason for liver rejection was alleged extreme steatosis, (6 of 9) or liver cirrhosis (3 of 9). Surprisingly, postoperative histological examinations only confirmed the clinical impression in one of nine cases. CONCLUSIONS: The clinical assessment of the explanting surgeon resulted in discarding eight of nine organs, potentially not contributing them to the donor pool of EUROTRANSPLANT. Further research is necessary to examine the accuracy of clinical evaluation of donor livers as well their correlation with histology.

Impact of donor dopamine on immediate graft function after kidney transplantation.

Optimizing medical donor management may have a considerable impact on transplantation outcome. This study investigated the effect of donor dopamine on initial graft function in renal allograft recipients, involving 254 consecutive recipients of a cadaver kidney, aged 18-74 years, transplanted between 1990 and 2003. Immunosuppression was based on cyclosporine. Patients were grouped according to donor use of dopamine during intensive care. Delayed graft function (DGF), and serial creatinine concentrations were compared between the groups. Dopamine-treated and -untreated donors were very similar regarding hemodynamics and renal function. Delayed graft function occurred in 47/158 treated and 48/96 untreated kidneys (p = 0.001). Donor dopamine was associated with a more rapid decrease of s-creatinine, which became obvious on the first postoperative day. Of patients in the treated and untreated group, respectively, 81.9% and 65.8% reached a s-creatinine level less than 2 mg/dL during the first month (p = 0.005). Donor dopamine remained predictive of a normalized s-creatinine level [HR 1.71; 95% CI 1.22-2.41] after controlling for confounding factors by multivariate Cox regression. Donor dopamine is associated with improvements of initial graft function after kidney transplantation. The beneficial effect of dopamine is achievable without side-effects for the recipients, and correlates with superior long-term graft survival.

[Abdominal drainages]. / Abdominelle Drainagen.

The use of drainages in abdominal surgery is characterized by tradition and personal experience of the surgeon. There are only a few high-quality, randomized studies on the use of prophylactic drainages. The risk of postoperative mediastinitis leads surgeons to maintain the use of drainages in esophageal anastomosis. The use of drainages in gastric and small bowel surgery appears to be negligible. There are evidence grade A recommendations for hepatobiliary surgery (without biliodigestive anastomosis) to abstain from the use of drainages. One prospective, randomized study showed an advantage of surgery without drainage in pancreatic resections (and bilioenteric anastomosis). The situation is clear for colorectal surgery. Several prospective, randomized studies have shown the advantages of avoiding drainages. The use of drainages in perforated appendicitis appears to be associated with an increased rate of postoperative complications. There are no general recommendations for the use of drainages in cases of peritonitis. The few high-quality studies published show that the use of drainages in visceral surgery has to be questioned continuously. High-quality clinical studies are necessary to obtain evidence-based recommendations for the use of drainages in visceral surgery.

Endotoxin tolerance in rats: influence on LPS-induced changes in excretory liver function.

OBJECTIVE AND DESIGN: We investigated in a rat model of endotoxic shock whether endotoxin tolerance (ETT) prevents lipopolysaccharide (LPS) associated lethality and studied the initial function of liver response to LPS. ANIMALS: Male Sprague-Dawley rats. TREATMENT: ETT was induced by i.p. injection of LPS (Salmonella friedenau) intraperitoneally over 5 days. Rats (n = 6 each group) received 1 mg LPS/kg b. w. intravenously (Salmonella friedenau). The common bile duct was then canalized and bile was collected every 60 min for 6 h. 1 h after LPS-application liver biopsies were taken for determination of TNF-alpha by RT-PCR. Sham operated animals (n = 6 each group) were treated identically but without application of LPS. RESULTS: All ETT animals survived the duration of the experiment whereas non-tolerant animals (NETT) died before the end of the experiment (5/6). NETT animals showed a continuous decrease in bile flow after 240 min. The amount of bile acids was significantly lower (ANOVA) in NETT animals than in sham operated controls or ETT-animals. Analysis of TNF-alpha mRNA expression in the liver revealed an upregulation 1 h after LPS application, which was significantly lower in LPS-tolerant animals. CONCLUSIONS: Our results show that excretory liver failure and death subsequent to intravenous LPS application can be successfully counteracted by induction of ETT.

[Results of emergency ERCP in the treatment of acute biliary pancreatitis]. / Ergebnisse der notfallmässigen ERCP bei der Behandlung der akuten biliären Pancreatitis.

Indication for emergency ERCP (< 48 hours after onset of symptoms) with stone extraction from the common bile duct (CBD) in patients with biliary pancreatitis remains controversial. In our hospital emergency ERCP with stone extraction from CBD is part of the therapeutical concept in patients with biliary pancreatitis. The aim of the study was to elucidate retrospectively results and impact of this concept on morbidity and lethality in surgical intensive care patients. We included all patients with a documented indication for emergency ERCP. Among 4 466 patients (1. 1. 1999-31. 12. 2000) treated in the SICU, 37 (0.9 %) required an emergency ERCP due to a biliary pancreatitis. (26 females/11 males, 62.0 +/- 15.4 years). After ERCP stones were present in 32 of the 37 patients with subsequent successful endoscopic extraction in all cases but one. The mean duration from admission to ERCP was 11.6 +/- 10.1 hours. Bilirubin as well as amylase and lipase decreased after ERCP (p < 0.05). Only in one case an elevation of pancreatic enzymes over the pre-ERCP values was observed, an aggravation of pancreatitis was not seen in our series. In 5 of the 37 cases bile duct stones were not found after ERCP despite strong clinical suggestion (elevation of bilirubin and pancreatic enzymes, ultrasound). During the observational period 2 patients died, in one case possibly due to the ERCP. Emergency ERCP removed in our series the pancreatitis causing agent. Still considering the limitations of a retrospective study these positive results are stimulating us to continue with our therapeutical concept.

Effects of endotoxin tolerance on liver function after hepatic ischemia/reperfusion injury in the rat.

OBJECTIVE: It is known that endotoxin tolerance prevents lethality after ischemia/reperfusion injuries (e.g., myocardial infarction) in laboratory animals. We used a rat model of partial hepatic ischemia/reperfusion to investigate whether endotoxin tolerance prevents associated lethality and disorders of liver function. DESIGN: Prospective animal study. SETTING: University research facility. SUBJECTS: Male Sprague-Dawley rats. INTERVENTIONS: Hepatic ischemia was initiated by atraumatic clipping across the portal venous and hepatic arterial blood supply to the left lateral lobe for 90 mins. The common bile duct was canalized, and in a second set of experiments the bile duct of the left lateral lobe was canalized selectively. Bile flow, bile acids, and transaminases were determined during ischemia and 300 mins of reperfusion in endotoxin-tolerant and -nontolerant rats. MEASUREMENTS AND MAIN RESULTS: Endotoxin-nontolerant animals showed a 50% lethality after hepatic ischemia/reperfusion injuries. All endotoxin-tolerant rats survived and did not react with any change in bile flow, showing a constant flow. The amount of bile acids in the common bile duct was reduced during ischemia and regained the concentrations of sham-operated animals 60 mins after reperfusion. From 180 mins after reperfusion, the difference between endotoxin-tolerant and -nontolerant animals was statistically significant. When bile acid concentration was determined in the ischemic left lateral lobe, ischemia/reperfusion was found to significantly decrease in endotoxin-nontolerant rats 60 mins after reperfusion. In contrast, endotoxin-tolerant rats produced normal amounts of bile acids 60 mins after reperfusion. At 120 mins after reperfusion, the amount of bile acids in the formerly ischemic left lateral lobe was more than normal. CONCLUSIONS: In this model of partial hepatic ischemia/reperfusion, endotoxin tolerance prevents ischemia/reperfusion injury-associated lethality and local disorders of liver function. This phenomenon induced by endotoxin tolerance may be useful in liver surgery to prevent ischemia/reperfusion injury.

Relevance of two-stage total hepatectomy and liver transplantation in acute liver failure and severe liver trauma.

Emergency liver transplantation frequently is the only life-saving procedure in cases of acute liver failure. It remains unclear whether emergency hepatectomy with portocaval shunt followed by liver transplantation as a two-stage procedure should be performed in cases in which a donor organ is not yet available. It has been stated that "toxic liver syndrome" could be treated by means of this strategy. From 1990 to 1995 we performed emergency hepatectomies in eight cases of acute liver failure or traumatic liver rupture with exsanguinating bleeding. In six cases we were able to perform a subsequent liver transplantation. Five of the six patients who underwent an emergency hepatectomy died. Emergency hepatectomy led to a significant increase in epinephrine dosage until the transplantation was performed. Only after transplantation did the need for epinephrine therapy decrease. The need for oxygen support did not change during the entire observation period. Plasmatic coagulation was stabilized by substitution, showing significantly higher values at 24 h after transplantation than at 48 h before transplantation. Fibrinogen increased significantly after transplantation in this group of patients. The experiences gathered at our clinic, however, do not show advantages that would allow a recommendation of emergency hepatectomy and subsequent liver transplantation as a two-stage procedure except for situations of severe and uncontrollable hepatic bleeding. Considering the progressive destabilization of our patients, fast procurement of donor organs seems to be of imminent importance for the outcome.

Outcome and management of blunt liver injuries in multiple trauma patients.

BACKGROUND: In Germany, abdominal trauma in multiple- trauma patients can be observed in about 25-35% of all cases. Due to major bleeding complications, the initial treatment of blunt abdominal trauma in multiple-trauma patients has high priority. The aim of this study was to discuss management, treatment and outcome of blunt liver injury in multiple-trauma patients treated in our department. METHODS: The clinical records of 1192 multiple-trauma patients [injury severity score (ISS) 3-18] treated at the Surgical Department of the University Clinic of Essen from January 1975 to February 1998 were reviewed. Seventy-five patients with an ISS above 18 operated on due to a blunt liver injury could be included. The mean age was 29.82+/-1.80 years (60 males and 15 females). The degree of injury in this group was high (ISS 37.12+/-1.06). RESULTS: Twenty-three of the 75 (30.6%) patients died during their hospital stay. Deceased patients were older (27+/-2 years versus 37+/-4 years; P<0.01) and had a higher ISS (ISS=34.5+/-1 versus 43.2+/-2; P<0.01). In nine cases, death was strongly related to liver injury. Operational blood loss was higher in the group of multiply injured patients with liver injury and in those patients who did not survive (P<0.05). An increased mortality could be seen in this selected patient group when compared with our large collective of multiply injured patients. The age of the patients, the ISS and operative blood loss were the significant factors that influenced the operative mortality after blunt hepatic injuries in our study.

Endotoxin tolerance in rats: expression of TNF-alpha, IL-6, IL-10, VCAM-1 AND HSP 70 in lung and liver during endotoxin shock.

Endotoxin can induce a state of tolerance against its own pathological effects, commonly referred to as endotoxin tolerance. This phenomenon has been found to be associated with reduced serum levels of cytokines such as TNF-alpha, IL-1, IL-6 and IL-10. In the present study the expression of TNF-alpha, IL-6, IL-10, the adhesion molecule VCAM-1 and the heat shock protein 70 was determined in vivo in lung and liver of LPS-tolerant and naive rats by means of semiquantitative RT-PCR after i.v. LPS injection. TNFalpha, IL-6, IL-10, HSP 70 and VCAM-1 were induced in lung and liver after LPS injection. In liver and lung of endotoxin-tolerant rats TNF-alpha and IL-6 were induced to a lower degree after LPS treatment when compared to non-tolerant controls. The LPS-induced IL-10 expression was also slightly attenuated in the lung of tolerant rats, but in the liver no differences between tolerant and non-tolerant animals were observed. HSP 70 and VCAM-1 were expressed after systemic LPS treatment in liver and lung. The degree of induction, however, was the same in tolerant and untreated controls. The presented data show that endotoxin tolerance is reflected by a reduced cytokine expression in lung and liver in vivo. On the other hand, levels of expression of the adhesion molecule VCAM-1 and the stress protein HSP 70 do not appear to be changed by endotoxin tolerance.

Impact of CT in patients with sepsis of unknown origin.

PURPOSE: To evaluate the diagnostic relevance of CT in patients with sepsis of unknown origin. MATERIAL AND METHODS: Sixty-three consecutive intensive care patients with suspicion of an abscess and negative or inconclusive previous radiological examinations were included. CT was performed using the helical technique. A total of 45 abdominal and 38 chest examinations were evaluated. RESULTS: 5/38 examinations of the chest revealed the source of sepsis (pleural empyema 2, lung abscess 1, mediastinitis 1, retrosternal abscess 1). 7/45 abdominal CT examinations showed the source of sepsis (intraabdominal abscess 2, hepatic abscess 3, intestinal perforation 1, gangrenous colitis 1). CONCLUSION: CT is useful for the evaluation of patients with fever or sepsis without a known source. Due to the detection of a septic focus by CT, 19% of the patients in our study could be immediately referred to causal therapy as percutaneous drainage or surgery.

[Surgical management of ruptured abdominal aortic aneurysm--diagnosis, risk factors and prognosis]. / Chirurgische Versorgung des rupturierten Bauchaortenaneurysmas--Diagnose, Risikofaktoren und Prognose.

It has been observed that the number of emergency operations for ruptured abdominal aortic aneurysms (AAA) is still high, as is the corresponding mortality. With the aim to determine how pre-clinical as well as clinical factors affect survival of patients with perforated AAA, we examined the course of patients admitted with perforated AAA in the last six years. Retrospectively we assessed the following documented parameters: patient's age, pre-clinical interval between onset of symptoms and hospitalization, the preoperative circulatory situation, hospital resuscitation period before surgery, the duration of aortic cross-clamping and the need of intraoperative blood transfusions in relation to the hospital mortality. In the period between 1.1.1990-31.12.1995, 39 patients with ruptured abdominal aortic aneurysms were operated on emergency basis in the Department of General Surgery of the University of Essen. There were 36 men and 3 women. The average age was 69.1 years. 25 patients (64%) died on admission, 4 of them intraoperatively. The most relevant observed prognostic factors were the preoperative circulatory status (systolic blood pressure p < 0.0001; hemoglobin p < 0.01) as well as the intraoperative blood transfusion requirement (p < 0.01) In view of the high mortality associated with surgical treatment of ruptured AAA and with the difficulty to decisively influence the relevant prognostic factors, early elective surgery of asymptomatic patients with AAA is highly recommended.

Prevalence of diverticulosis and incidence of bowel perforation after kidney transplantation in patients with polycystic kidney disease.

Sigmoid perforation due to diverticulitis is a life-threatening complication in the postoperative course of allogenic kidney transplantation. The incidence of diverticulosis is especially high among patients with autosomal dominant polycystic kidney disease (ADPKD). Thus, those who undergo allogenic kidney transplantation represent a high-risk group. The aim of this study was to evaluate the prevalence of diverticulosis in ADPKD patients awaiting renal transplantation and the incidence of bowel perforation following allogenic kidney transplantation due to ADPKD. Within the group of 1128 patients who underwent transplantation between January 1974 and January 1990, there were 46 patients (4.07%) whose indication for transplantation was ADPKD. There was one patient who developed a sigmoid perforation under postoperative immunosuppression. Surgical treatment was a discontinuity resection of the sigmoid (Hartmann's procedure). The postoperative course was favorable, the bowel continuity has already been restored, and the graft is still functioning well. Fifteen of the 28 (53.5%) ADPKD patients awaiting transplantation had colon diverticulosis (12 male and 3 female patients). No case of bowel perforation has thus far been observed in 15 of these patients who have undergone transplantation. A sigmoid resection was necessary in one patient due to diverticulitis without perforation. We did not find a higher prevalence of diverticulosis in patients with ADPKD, nor did we see a higher incidence of sigmoid perforation during post-transplant immunosuppression in this study.

Mediators of antigen-induced gastrin release: role of antigen-antibody complexes and the complement system.

That orally administered antigen was shown to induce gastrin release in immunized animals was a new aspect of gastrointestinal physiology. The mediators responsible for this immunological effect are still unclear. In an attempt to discover more about the mechanisms regarding antigen-induced gastrin release, we developed an in vitro system where fragments of rat antral mucosa were challenged. This makes it possible to determine the role of antigen-antibody complexes and the complement system in the mechanism of antigen-induced gastrin release. Wistar rats were immunized in vivo with NIP-OVA and mucosal fragments were challenge, in vitro with NIP-HGG. Gastrin was determined after a preincubation and a challenged incubation period without supernatants. After antigenic challenge, supernatants were used for in vitro challenge in order to rule out the presence of a soluble mediator and activation of complement. In a second group of experiments Wistar rats were used to study in vitro the release of specific antibodies after antigenic challenge. With this experimental design we were able to show increased gastrin secretion after antigenic challenge in vitro in the presence of intact tissue. It is shown that the increased gastrin release is most probably mediated by activation of the complement system in the presence of antigen-antibody complexes. These are built up by specific anti-NIP antibodies and NIP-HGG used for the challenge. The complement system might be the final pathway of the observed increased gastrin release.

The anastomotic stoma: a useful procedure in emergency bowel surgery.

In emergency surgery of the bowel a primary anastomosis may be risky. Discontinuing colostomies have the disadvantage that a secondary laparotomy is necessary to restore continuity. If sufficient bowel loop mobilization is possible, we prefer to perform an anastomotic stoma. After resection of the diseased bowel segment, we bring the proximal and distal loop together and proceed to the anastomosis of the posterior wall. The anterior wall of the anastomosis remains open and is then fixed to the abdominal wall as a stoma. So far, we have used this method in 91 patients. In 73 cases this technique was performed during emergency operations. No patient died as a result of complications of the method: 21 patients, however, died as a consequence of their primary disease. Bowel continuity could be restored in 78 cases. The anastomotic stoma protects the posterior wall from elevated pressure and allows daily control of the anastomosis. In the case of extraperitoneal closure, a secondary laparotomy for reconstruction of the continuity is not necessary. The anastomotic stoma can be performed in most regions of the small and large bowel.

[Perforation of the heart wall--a rare complication after thoracic drainage treatment]. / Herzwandperforation--seltene Komplikation nach Anlegen einer Thoraxdrainage.

Complications after chest-tube treatment are rare if the correct technique is used. We describe a case of an iatrogenic perforation of the heart after bringing in a chest tube to treat a ventral pneumothorax during the postoperative intensive care treatment.