Resectability of bilobar liver tumours after simultaneous portal and hepatic vein embolization versus portal vein embolization alone: meta-analysis

BACKGROUND

Many patients with bi-lobar liver tumours are not eligible for liver resection due to an insufficient future liver remnant (FLR). To reduce the risk of posthepatectomy liver failure and the primary cause of death, regenerative procedures intent to increase the FLR before surgery. The aim of this systematic review is to provide an overview of the available literature and outcomes on the effectiveness of simultaneous portal and hepatic vein embolization (PVE/HVE) versus portal vein embolization (PVE) alone.

METHODS

A systematic literature search was conducted in PubMed, Web of Science, and Embase up to September 2022. The primary outcome was resectability and the secondary outcome was the FLR volume increase.

RESULTS

Eight studies comparing PVE/HVE with PVE and six retrospective PVE/HVE case series were included. Pooled resectability within the comparative studies was 75 per cent in the PVE group (n = 252) versus 87 per cent in the PVE/HVE group (n = 166, OR 1.92 (95% c.i., 1.13-3.25)) favouring PVE/HVE (P = 0.015). After PVE, FLR hypertrophy between 12 per cent and 48 per cent (after a median of 21-30 days) was observed, whereas growth between 36 per cent and 67 per cent was reported after PVE/HVE (after a median of 17-31 days). In the comparative studies, 90-day primary cause of death was similar between groups (2.5 per cent after PVE versus 2.2 per cent after PVE/HVE), but a higher 90-day primary cause of death was reported in single-arm PVE/HVE cohort studies (6.9 per cent, 12 of 175 patients).

CONCLUSION

Based on moderate/weak evidence, PVE/HVE seems to increase resectability of bi-lobar liver tumours with a comparable safety profile. Additionally, PVE/HVE resulted in faster and more pronounced hypertrophy compared with PVE alone.

Dragon 1 Protocol Manuscript: Training, Accreditation, Implementation and Safety Evaluation of Portal and Hepatic Vein Embolization (PVE/HVE) to Accelerate Future Liver Remnant (FLR) Hypertrophy

STUDY PURPOSE

The DRAGON 1 trial aims to assess training, implementation, safety and feasibility of combined portal- and hepatic-vein embolization (PVE/HVE) to accelerate future liver remnant (FLR) hypertrophy in patients with borderline resectable colorectal cancer liver metastases.

METHODS

The DRAGON 1 trial is a worldwide multicenter prospective single arm trial. The primary endpoint is a composite of the safety of PVE/HVE, 90-day mortality, and one year accrual monitoring of each participating center. Secondary endpoints include: feasibility of resection, the used PVE and HVE techniques, FLR-hypertrophy, liver function (subset of centers), overall survival, and disease-free survival. All complications after the PVE/HVE procedure are documented. Liver volumes will be measured at week 1 and if applicable at week 3 and 6 after PVE/HVE and follow-up visits will be held at 1, 3, 6, and 12 months after the resection.

RESULTS

Not applicable.

CONCLUSION

DRAGON 1 is a prospective trial to assess the safety and feasibility of PVE/HVE. Participating study centers will be trained, and procedures standardized using Work Instructions (WI) to prepare for the DRAGON 2 randomized controlled trial. Outcomes should reveal the accrual potential of centers, safety profile of combined PVE/HVE and the effect of FLR-hypertrophy induction by PVE/HVE in patients with CRLM and a small FLR.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT04272931 (February 17, 2020). Toestingonline.nl: NL71535.068.19 (September 20, 2019).

Immuno-activated highly expressed PD-1 phenotype in hepatocellular carcinoma is associated with lower recurrence

Objective

Hepatocellular carcinoma (HCC) accounts for 75–85% of all primary liver malignancies. Curative treatments in early-stage HCC are hampered by high recurrence rates, and targeted therapies against HCC are rare. Little is known about the impact of tumor microenvironment (TME) in HCC. One immunomodulatory strategy used by malignant tumors is the expression of programmed cell death receptor 1 ligand (PD-L1), whose receptor is expressed on activated T cells (PD-1). The use of immune checkpoint inhibitors (ICI) blocking this interaction has shown antitumor activity and unprecedented rates of durable clinical responses in various cancer types. In HCC, ICI are described as possible second-line therapies. It is known from other tumor entities that expression of PD-1 and PD-L1 in the TME has prognostic importance and can predict response to ICI. The aim of our study was to investigate the impact of PD-1 and PD-L1 expression on HCC recurrence and its relation to cancer-immune phenotypes.

Methods

Immunohistochemical staining was performed on archival tissue from 94 HCC, primary and recurrent, using the following antibodies: NAT105 (PD-1) and Ventana SP263 (PD-L1). Based on this protein expression, tumors were classified as immunologically active, excluded or deserted. PD-1 and PD-L1 immunoreactivity was evaluated as the proportion of positive cells compared to the total number of immune cells (0%, <1%, and >1%).

Results

Basic tumor characteristics were not related to recurrence of HCC. PD-1 expression >1% (78%; 38/49) was associated with a significantly lower recurrence rate compared to tumors with <1% PD-1 expression (p=0.048). Of note, HCC classified as immune active were also enriched for PD-1 expression >1% (77%; 49/64). Additionally, they also showed a significantly lower recurrence rate, especially in combination with PD-1 expression of >1% (p=0.066). Conversely, an association between HCC recurrence and PD-L1 expression on tumor cells was not found.

Conclusion

Consistent with previous reports, an association between PD-1 expression on immune cells and lower HCC recurrence was found. Furthermore, the results suggest that HCC recurrence is less frequent in immune-activated tumors. The use of therapeutic anti-PD-1 antibodies as an adjuvant therapy should thus be further investigated.

Predicting complicated appendicitis based on clinical findings: the role of Alvarado and Appendicitis Inflammatory Response scores

PURPOSE

The pre-interventional differentiation between complicated and uncomplicated appendicitis is decisive for treatment. In the context of conservative therapy, the definitive diagnosis of uncomplicated appendicitis is mandatory. This study investigates the ability of clinical scoring systems and imaging to differentiate between the two entities.

METHODS

This is a retrospective analysis of two cohorts from two tertiary referral centers in Switzerland and Germany. All consecutive patients underwent appendectomy between January 2008 and April 2013 (in the first cohort) or between January 2017 and June 2019 (the second cohort). Exclusion criteria did not apply as all patients found by the database search and received an appendectomy were included. Diagnostic testing and calculation of a receiver operating curve were performed to identify a cutoff for clinical scores that resulted in a minimum sensitivity of 90% to detect complicated appendicitis. The cutoff was combined with additional diagnostic imaging criteria to see if diagnostic properties could be improved.

RESULTS

Nine hundred fifty-six patients were included in the analysis. Two hundred twenty patients (23%) had complicated appendicitis, and 736 patients (77%) had uncomplicated appendicitis or no inflammation. The complicated appendicitis cohort had a mean Alvarado score of 7.03 and a mean AIR of 5.21. This compared to a mean Alvarado of 6.53 and a mean AIR of 4.07 for the uncomplicated appendicitis cohort. The highest Alvarado score with a sensitivity of > 90% to detect complicated appendicitis was ≧ 5 (sensitivity = 95%, specificity 8.99%). The highest AIR score with a sensitivity of > 90% to detect complicated appendicitis was ≧ 3 (sensitivity 91.82%, specificity 18.53). The analysis showed that additional CT information did not improve the sensitivity of the proposed cut-offs.

CONCLUSION

AIR and Alvarado scores showed limited capability to distinguish between complicated and uncomplicated appendicitis even with additional imaging in this retrospective cohort. As conservative management of appendicitis needs to exclude patients with complicated disease reliably, appendectomy seems until now to remain the safest option to prevent undertreatment of this mostly benign disease.

Oral health-related quality of life of patients after solid organ transplantation is not affected by oral conditions: results of a multicentre cross-sectional study

Background

This multicentre cross-sectional study aimed in examination of oral health-related quality of life (OHRQoL) of patients after solid organ transplantation (SOT).

Material and Methods

Patients after SOT (liver, lung and heart) at one out of three German centers (Goettingen, Essen, Leipzig) were included. For comparison, a healthy control (HC) was recruited. OHRQoL was assessed by German short form of oral health impact profile (OHIP G14). Oral examination comprised: decayed-, missing- and filled-teeth index (DMF-T), remaining teeth and periodontitis severity.

Results

In total, 196 patients after SOT and 130 HC with comparable age, gender and smoking habits were included (p>0.05). DMF-T and number of remaining teeth was worse in SOT group (p<0.01). OHIP G14 sum score was significantly higher in SOT (3.49 ± 5.73 vs. 1.33 ± 2.63, p<0.01). In contrast to HC, in SOT no associations between OHIP G14 and oral health parameters were found (p>0.05). Number of remaining teeth was not an independent predictor of OHIP G14 sum score in SOT (β -0.082, CI95 -0.156 - 0.045, p=0.28).

Conclusions

OHRQoL of SOT recipients is not affected by their oral condition, leading to the assumption that the individual perception of patients physical oral health is not in line with the clinical situation.

Key words:Oral health, oral health-related quality of life, solid organ transplantation.

Does persistent cholecystitis after cholecystostomy increase mortality?

Objective

Numerous publications describe percutaneous cholecystostomy (PC) as a possible treatment option for acute cholecystitis (AC) in selected cases where laparoscopic or open cholecystectomy (CHE) is not feasible due to limited health conditions. Whereas certain experts propose PC as a definitive therapy option for AC, a number of studies question the use of PC, due to high complication rates, no additional benefit of PC compared to CHE, and an increased mortality. The aim of our study was to retrospectively analyze the outcome of patients treated with PC over an extended period of time.

Methods

We conducted a retrospective study of patients who underwent PC for AC at a tertiary referral hospital during the last 10 years. The collected data included basic demographics, details about PC procedure, outcome, surgical-rate and final histologic diagnosis.

Results

Out of 158 patients (median age 75 years) treated with PC for AC, 47 (30%) died without undergoing subsequent CHE. Half of the PC patients (79) underwent subsequent CHE (8% in the hot phase), with 97% of these patients undergoing subsequent CHE within one year after PC. Seven (5%) of them died within the first year. The overall Charlson Comorbidity Index (CCI) was 6.4 (CHE vs. no CHE 5.3 vs. 7.4). Histologically, 22 (29%) of the 75 analyzed specimens showed chronic cholecystitis (CC), and 57 patients (68%) had signs of an AC. In 48 patients (30%), a complication after PC occurred.

Conclusion

In our collective, the 1-year survival after PC was 72%. The majority of these patients were in limited health conditions with a mean pre-PC CCI &gt; 5, which implies a potential one-year mortality rate of over 85%. Histologic examination of almost all cholecystectomy specimens showed persistent inflammation. To our knowledge, this is the first extensive report of histologic findings in gallbladder specimens after PC.

Based on our findings, especially in view of the high mortality rate of PC patients, we propose CHE as the treatment of choice in AC, even in chronically ill and elderly patients after stabilization, e.g. with a PC. PC represents no definitive treatment for AC and should remain a short-term solution because of the persistent inflammatory focus. Because CHE in a critically ill patient can be challenging, it should be performed by the most experienced surgeons.

Association of time under immunosuppression and different immunosuppressive medication on periodontal parameters and selected bacteria of patients after solid organ transplantation

Background

Aim of this study was to investigate the association of the time under immunosuppression and different immunosuppressive medication on periodontal parameters and selected periodontal pathogenic bacteria of immunosuppressed patients after solid organ transplantation (SOT).

Material and Methods

169 Patients after SOT (lung, liver or kidney) were included and divided into subgroups according their time under (0-1, 1-3, 3-6, 6-10 and >10 years) and form of immunosuppression (Tacrolimus, Cyclosporine, Mycophenolate, Glucocorticoids, Sirolimus and monotherapy vs. combination). Periodontal probing depth (PPD) and clinical attachment loss (CAL) were assessed. Periodontal disease severity was classified as healthy/mild, moderate or severe periodontitis. Subgingival biofilm samples were investigated for eleven selected potentially periodontal pathogenic bacteria using polymerasechainreaction.

Results

The mean PPD and CAL as well as prevalence of Treponema denticola and Capnocytophaga species was shown to be different but heterogeneous depending on time under immunosuppression (p<0.05). Furthermore, only the medication with Cyclosporine was found to show worse periodontal condition compared to patients without Cyclosporine (p<0.05). Prevalence of Porphyromonas gingivalis, Tannerella forsythia and Fusobacterium nucleatum was reduced and prevalence of Parvimonas micra and Capnocytophaga species was increased in patients under immunosuppression with Glucocorticoids, Mycophenolate as well as combination therapy.

Conclusions

Time under and form of immunosuppression might have an impact on the clinical periodontal and microbiological parameters of patients after SOT. Patients under Cyclosporine medication should receive increased attention. Differences in subgingival biofilm, but not in clinical parameters were found for Glucocorticoids, Mycophenolate and combination therapy, making the clinical relevance of this finding unclear.

Key words:Immunosuppression, organ transplantation, periodontitis, periodontal bacteria.

Oral health-related quality of life in patients on chronic haemodialysis and after kidney transplantation

OBJECTIVES

The objective of the study was to evaluate oral health-related quality of life (OHRQoL) depending on dental and periodontal situation in patients on haemodialysis (HD) and after kidney transplantation (KTx) compared to healthy controls (HC).

SUBJECTS AND METHODS

OHRQoL was assessed using the German short form of Oral Health Impact Profile (OHIP G14). Dental health was estimated using the decayed, missing and filled teeth index (DMF-T). Periodontal health was classified as healthy/mild or moderate/severe periodontitis.

STATISTICAL ANALYSIS

Mann-Whitney U-test, Kruskal-Wallis test, chi-square test and Fisher's test.

RESULTS

Eighty-seven HD patients, 39 KTx patients and 91 HC were included. Significant differences in DMF-T, D-T, M-T and F-T scores were identified between groups (P < 0.001). The prevalence of moderate/severe periodontitis was significantly higher in the HD and KTx group compared to HC (P = 0.002). Differences in OHIP G14 between groups were neither clinical relevant nor statistically significant (P = 0.199). A significant effect of DMF-T (P = 0.012), M-T (P < 0.001) and periodontitis (P = 0.023) on the OHIP G14 scores was identified only in HC.

CONCLUSIONS

Improvement in dental care of HD and KTx patients is required. OHIP G14 values provide a subjectively considered low importance of oral health in HD and KTx patients, leading to need of motivation and sensitisation of these patients.

Proangiogenic potency of MUC18 in arteriosclerotic disease

AIM

Stenotic peripheral and dilatative arteriosclerotic diseases have different pathomechanism although associations between both diseases are well known. The adhesion molecule MUC18 is a cell membrane glycoprotein also known as the melanoma cell adhesion molecule. As MUC18 has proangiogenic potency in melanoma and prostate cancer this study investigated the role of MUC18 in patients with stenotic or dilatative arteriosclerotic disease as a putative biochemical marker.

METHODS

Using qRT-PCR, Western Blot and immunohistochemistry techniques, the expression of MUC18 in arteriosclerotic arteries from major lower limb amputates (AP, N.=15) as well as specimen from femoral endarterectomies (TEA, N.=20) and in dilatative aortic diseases using abdominal aortic aneurysms (AAA, N.=13) was evaluated. Human visceral arteries without macroscopic arteriosclerosis from liver transplants served as controls (AN, N.=19).

RESULTS

MUC18 mRNA and protein expression could be found in AN, AP, TEA and AAA tissues. Immunohistochemical analysis showed that a complete and intact intima was the predominant location of MUC18 expression. Although in stenotic arteriosclerotic disease (AP and TEA) the intima was widely calcified, qRT-PCR analysis showed overexpression compared to normal tissue. Interestingly, MUC18 expression was significantly down-regulated in dilatative compared to stenotic arteriosclerotic disease and normal arteries.

CONCLUSION

In peripheral stenotic arteriosclerotic disease the proangiogenic potency of MUC18 may play a role in angiogenesis of collaterals, whereas in dilatative aortic diseases the induction of collaterals is typically not evident. The results support the hypothesis of a role in angiogenesis of MUC18 in stenotic arteriosclerotic disease.

Improved survival in liver transplant recipients receiving prolonged-release tacrolimus in the European Liver Transplant Registry

This study was a retrospective analysis of the European Liver Transplant Registry (ELTR) performed to compare long-term outcomes with prolonged-release tacrolimus versus tacrolimus BD in liver transplantation (January 2008-December 2012). Clinical efficacy measures included univariate and multivariate analyses of risk factors influencing graft and patient survival at 3 years posttransplant. Efficacy measures were repeated using propensity score-matching for baseline demographics. Patients with <1 month of follow-up were excluded from the analyses. In total, 4367 patients (prolonged-release tacrolimus: n = 528; BD: n = 3839) from 21 European centers were included. Tacrolimus BD treatment was significantly associated with inferior graft (risk ratio: 1.81; p = 0.001) and patient survival (risk ratio: 1.72; p = 0.004) in multivariate analyses. Similar analyses performed on the propensity score-matched patients confirmed the significant survival advantages observed in the prolonged-release tacrolimus- versus tacrolimus BD-treated group. This large retrospective analysis from the ELTR identified significant improvements in long-term graft and patient survival in patients treated with prolonged-release tacrolimus versus tacrolimus BD in primary liver transplant recipients over 3 years of treatment. However, as with any retrospective registry evaluation, there are a number of limitations that should be considered when interpreting these data.

Liver injury following blunt abdominal trauma: a new mechanism-driven classification

Purposes

The current classifications for blunt liver trauma focus only on the extent of liver injury. However, these scores are independent from the localization of liver injury and mechanism of trauma.

Methods

The type of liver injury after blunt abdominal trauma was newly classified as type A when it was along the falciform ligament with involvement of segments IVa/b, III, or II, and type B when there was involvement of segments V–VIII. With the use of a prospectively established database, the clinical, perioperative, and outcome data were analyzed regarding the trauma mechanism, as well as the radiological and intraoperative findings.

Results

In 64 patients, the type of liver injury following blunt abdominal trauma was clearly linked with the mechanism of trauma: type A injuries (n = 28) were associated with a frontal trauma, whereas type B injuries (n = 36) were found after complex trauma mechanisms. The demographic data, mortality, ICU stay, and hospital stay showed no significant differences between the two groups. Interestingly, all patients with type A ruptures required immediate surgical intervention, whereas six patients (16.7 %) with type B ruptures could be managed conservatively.

Conclusions

This new classification for blunt traumatic hepatic injury is based on the localization of parenchymal disruption and correlates with the mechanism of trauma. The type of liver injury correlated with the necessity for surgical therapy.

Octreotide prophylaxis is not beneficial for biochemical activity and clinical severity of postoperative pancreatic fistula after pancreatic surgery

BACKGROUND

Prospective randomized trials indicate that prophylactic octreotide treatment does not decrease the incidence of postoperative pancreatic fistula (POPF). The aim of this study was to analyze if octreotide prophylaxis could decrease the severity grade of POPFs after pancreatic surgery.

METHOD

Seventy-eight of 684 patients undergoing pancreatic resection with POPF were included in the study. Prophylactic octreotide treatment was started immediately after surgery and was performed in 22 patients, whereas 56 patients had no octreotide treatment and served as controls. Lipase activity was measured in the abdominal drainage on postoperative days (POD) 3, 5 and 7. Primary endpoints of the study were clinical severity of the POPF and lipase activity in the drainage.

RESULTS

There was no significant difference concerning length of postoperative hospital stay. Lipase activity in the abdominal drainage was not influenced by octreotide prophylaxis at POD 5 or 7 compared to POD 3. Multivariate analysis showed that the risk to develop a type B or C fistula in the octreotide group was independent of the kind of operation and the consistency of the pancreas (RR = 3.4; CI = 1.0-11.7; p = 0.050 and RR = 6.3; CI = 1.4-29.6; p = 0.019).

CONCLUSION

Octreotide prophylaxis after pancreatic surgery has no beneficial effect on clinical severity of POPF.

A comparative evaluation of ablations produced by high-frequency coagulation-, argon plasma coagulation-, and cryotherapy devices in porcine liver

INTRODUCTION

Hepatic resection is the only curative treatment option for primary or metastatic malignancies of the liver. Although R1 resections can also lead to prolonged survival, the main surgical goal is complete tumor resection (R0). To achieve this, additional treatment of the resection margin with ablation devices is discussed. Using a porcine in vivo model, we therefore analyzed the effect of different ablation devices on depth and completeness of hepatic parenchymal cell destruction.

METHODS

Swabian-Hall strain pigs underwent ablation on the surface of the right, middle, or left liver lobe using seven different types of high-frequency (HF)-, cryotherapy (Cryo)-, or argon plasma coagulation (APC) devices. Penetration depth and volume were analyzed from histological sections. Severity of parenchymal cell destruction was assessed by a histomorphological score.

RESULTS

The greatest penetration depth was achieved with Cryo (10.4 ± 1.7 mm), whereas HF and APC exhibited a smaller penetration depth. However, HF and APC compared to Cryo achieved complete destruction of the intralobular architecture and hepatocellular morphology depending on the application time and the adjusted power.

CONCLUSION

HF, APC, and Cryo applied to the liver surface induce different parenchymal penetration depth and cell destruction. HF and APC are considered to be standard surgical instruments and therefore recommended as standard treatment, whereas Cryo may be used only if particularly deep penetration is required.

Hepatic arterial infusion with tumor necrosis factor-α induces early hepatic hyperperfusion

BACKGROUND

Hepatic arterial infusion (HAI) has been developed for high-dose regional chemotherapy of unresectable liver metastases or primary liver malignancies. While it is well known that high concentrations of tumor necrosis factor (TNF)-α damage tumor blood perfusion, there is no information on whether autochthonous liver perfusion is affected by HAI with TNF-α. Therefore, we investigated the effects of HAI with TNF-α on hepatic macro- and microvascular perfusion.

METHODS

Swabian Hall pigs were randomized into three groups. HAI was performed with either 20 or 40 µg/kg body weight TNF-α (n = 6 each group). Saline-treated animals served as controls (n = 6). Analyses during a 2-hour post-HAI observation period included systemic hemodynamics, portal venous and hepatic arterial blood flow, portal venous pressure, and the blood flow in the hepatic microcirculation.

RESULTS

HAI with TNF-α caused a slight decrease of mean arterial blood pressure (p < 0.001), which was compensated by a moderate increase of heart rate (p < 0.001). No further systemic side effects of TNF-α were observed. HAI with TNF-α further caused a slight but not significant decrease of portal venous blood flow (p = 0.737) in both experimental groups, paralleled by an increase of hepatic arterial blood flow (p = 0.023, 20 µg/kg; p = 0.034, 40 µg/kg) resulting in an overall hepatic hyperperfusion. The hepatic hyperperfusion after HAI with 20 µg/kg TNF-α was more pronounced and associated with a 40% decrease of the blood flow in the hepatic microcirculation (p = 0.009). HAI with 40 µg/kg TNF-α was only associated with a temporary and moderate total hepatic hyperperfusion and did not affect the blood flow in the hepatic microcirculation.

CONCLUSION

HAI with TNF-α causes a decrease of portal venous flow; however, this is overcompensated by an increased hepatic arterial blood flow, resulting in a total hepatic hyperperfusion. Moderate total hepatic hyperperfusion does not affect the blood flow in the hepatic microcirculation, while a persistent and more pronounced hyperperfusion may cause hepatic microcirculatory disturbances.

Graft-versus-host disease or toxic epidermal necrolysis: diagnostic dilemma after liver transplantation

Graft-versus-host disease (GvHD) and toxic epidermal necrolysis (TEN) are rare and severe complications after liver transplantation. While mild acute GvHD is quite different from TEN and easy to distinguish, severe acute GvHD and TEN can be hard to differentiate because of similar clinical symptoms. We herein report a case with rapid progression of critical illness, after liver transplantation, caused by GvHD or TEN, although between those, diagnosis was not possible during the clinical course. Although, based on the timing/progression of the symptoms and the chimerism of >40%, the case seemed much more clinically consistent with GVHD, the combination of clinical symptoms together with skin rashes and the histologic appearance of skin lesions indicated diagnosis of a Stevens-Johnson syndrome/TEN overlap. The true diagnostic dilemma in such cases is discussed in detail, as these cases emphasize the need for more advanced diagnostic techniques.

[Benchmarking surgical resources--a work sampling analysis at a German university hospital]

INTRODUCTION

Work densification caused by lack of young surgeons with increased clinical documentation keeps surgeons busy. It is proven by many studies that surgeons work significantly longer hours per week and deal with a larger amount of medical and non-medical documentation than staff members in conservative disciplines. The aim of the study was to investigate surgeons work distribution in a surgical university department and to evaluate by means of a work sampling analysis whether it can be standardised and slimmed down by systematic use of IT-supported, process-managed work-flow. In addition the data obtained are compared wuith those from other studies on similar topics.

METHODS

Based on the results of an independent pilot observational study, 21 surgeons (14 residents, 7 staff surgeons) had to document over a 10-day period in a self-observation once in an hour their actual activity in a two dimensional matrix concerning medical activity (13 items) and patient contact (5 items). After the study, each physician had to estimate his/her own work distribution. Real percentages of the self-observation study were compared to the physicians' estimates of work distribution. IT-supported clinical pathways have been implemented since 2004 in our department.

RESULTS

Over a ten-day evaluation period (1830 observation points), surgeons spent 30.2% of their activity in the operating theatre or on direct patient care. During 13.9% they were in meetings and they spent 10.8% of their time on documentation. Time needed for studying medical records (9.2%) and ward rounds (9.0%) ranged in a similar way. There was a significant accordance of estimated and real work distribution concerning the 5 most frequent daily activities. In only 14% there was no direct patient relationship.

CONCLUSION

Application of work sampling analysis in surgery is a valid procedure for the evaluation of work flows in the course of personal observations. Surgeons working time in a hospital is limited. To achieve a maximum of direct patient care, clinical documentation has to be optimised by process automatisation within the context of IT-supported clinical pathways. Surgeons are able to estimate very exactly the distribution of their daily activities so that data of working time estimations is valuable.

[Reduced time-frame for ward rounds and patient satisfaction]

INTRODUCTION

The introduction in 2006 of the European legislation restricting physicians work-ing hours has had a dramatic impact on working conditions. This restriction called for a marked improvement in hospital workflow, leading to a reduction of time spent on ward rounds. We conducted an opinion survey assessing patient satisfaction in the area of markedly reduced ward rounds.

MATERIALS AND METHODS

By January 2009, the time-frame allowed for morning ward rounds had been reduced by 33 % from 45 to 30 min. At the same time, the attendance of the senior staff surgeon was declared mandatory on each ward round. We conducted a prospective study, assessing patient satisfaction over a period of 3 months.

RESULTS

86 patients with an average age of 56.7 years were repeatedly questioned by a single investigator. Average length of hospital stay was 7.2 days. Patients expected ward rounds to average 5.3 min, which was significantly higher than actually observed. However, an overall patient satisfaction of above 80 % could be measured.

CONCLUSION

In spite of the reduced time spent on ward rounds, a high level of overall patient satisfaction can be obtained due to the regular attendance of a senior staff surgeon. Process management is furthermore endorsed by the routine -application of clinical pathways in patient management.

Tumour growth following portal branch ligation in an experimental model of liver metastases

BACKGROUND

Portal branch ligation (PBL) is being used increasingly before hepatectomy for colorectal metastases. This study evaluated the effect of PBL on angiogenesis, growth factor expression and tumour growth in a mouse model of hepatic colorectal metastases.

METHODS

CT26.WT cells were implanted into the left liver lobe of BALB/c mice. Animals underwent PBL of the left liver lobe or sham treatment. Angiogenesis, microcirculation, growth factor expression, cell proliferation and tumour growth were studied over 14 and 21 days by intravital multifluorescence microscopy, laser Doppler flowmetry, immunohistochemistry and western blotting.

RESULTS

Left hilar blood flow and tumour microcirculation were significantly diminished during the first 7 days after PBL. This resulted in tumour volume being 20 per cent less than in sham controls by day 14. Subsequently, PBL-treated animals demonstrated recovery of left hilar blood flow and increased expression of hepatocyte growth factor and transforming growth factor alpha, associated with increased cell proliferation and acceleration of growth by day 21.

CONCLUSION

PBL initially reduced vascular perfusion and tumour growth, but this was followed by increased growth factor expression and cell proliferation. This resulted in delayed acceleration of tumour growth, which might explain the stimulated tumour growth observed occasionally after PBL.

Randomized clinical trial of efficacy and costs of three dissection devices in liver resection

BACKGROUND

In recent decades a variety of instruments for liver dissection has become available. This randomized controlled trial analysed the efficacy and costs of three different liver dissection devices.

METHODS

Ninety-six patients without cirrhosis undergoing liver resection were randomized to either ultrasonic dissection, waterjet dissection or dissecting sealer (32 in each group). Patients were unaware of the device used. The primary endpoint was dissection speed. Secondary endpoints were intraoperative blood loss, morbidity and mortality, and costs of dissection devices, staplers and haemostatic agents.

RESULTS

Dissection was slower with the dissecting sealer (P = 0.004 versus waterjet dissector). The difference was more pronounced for extended resections (mean(s.e.m.) 1.62(0.36) cm(2)/min versus 3.42(0.53) and 3.63(0.51) cm(2)/min for ultrasonic and water dissectors respectively; P = 0.037). Costs were significantly higher for the dissecting sealer when atypical or segmental resections were performed. Four patients died after extended resections; postoperative complications did not differ between groups.

CONCLUSION

The dissecting sealer is slower than the ultrasonic dissector or water dissector. The three devices are equally safe in terms of blood loss, transfusions and postoperative complications. Ultrasonic and water dissectors might be more favourable economically than the dissecting sealer.

REGISTRATION NUMBER

ISRCTN52294555 (http://www.controlled-trials.com).

Analysis of spinal kinematics following implantation of lumbar spine disc prostheses versus fusion: radiological study

STUDY DESIGN

This is a prospective controlled study comparing lumbar spine disc replacement versus fusion for monosegmental degenerative disc disease (DDD). SUMMARY OF BACKGROUND DATA AND OBJECTIVE: Fusion has been reported to be the standard therapy by DDD of the lumbar spine. Due to unsatisfactory long-term results of fusion by progressive adjacent level degeneration, disc replacement was developed and thought to reduce pain while restoring disc height and motion at the affected level. The expected long-term advantage of disc replacement over fusion is the preservation of motion. This again is very difficult to judge; therefore the aim of the current study was to analyze segmental motion following disc replacement versus fusion.

METHODS

Patients meeting inclusion criteria were consented for the study. This analysis includes data up to 12 months from the first included patients. There were 13 patients who underwent disc replacement, and 11 patients had fusion procedures. Radiostereometric analysis was done 1 and 6 weeks and 3, 6, and 12 months after surgery.

RESULTS

The mobility provocation RSA showed a significant segmental motion in the disc replacement group in comparison to fusion.

CONCLUSIONS

Disc replacement using Active L prostheses preserves segmental motion during the period examination time of 12 months.

Differential CXC receptor expression in colorectal carcinomas

In this study, we aimed to assess the expression profile of chemokine receptors CXCR1-4 in inflammatory and malignant colorectal diseases and corresponding hepatic metastases of synchronous and metachronous origin to elucidate their role in colorectal cancer (CRC) progression and metastasis. Chemokine receptor expression was assessed by quantitative real-time PCR, immunohistochemistry (IHC) and Western blot analysis in resection specimens from patients with ulcerative colitis (UC, n = 25), colorectal adenomas (CRA, n = 8), different stages of CRC (n = 48) as well as colorectal liver metastases (CRLM) along with their corresponding primary colorectal tumours (n = 16). While none of the chemokine receptors were significantly upregulated or downregulated in UC or CRA tissues, CXC receptors 1, 2 and 4 demonstrated a significant increase in expression in all tumour stages of CRC specimens with CXCR4 correlating with tumour grading (P < 0.05). On the other hand, CXCR3 showed no significant upregulation in either tumour stage, but significant overexpression in CRLM. While CXCR4 demonstrated significant upregulation in both tumour entities, IHC analysis revealed that the predominate cell type expressing CXCR4 in CRC is represented by tumour cells, whereas in CRLM the majority of positive CXCR4 signals is due to hepatocytes along the tumour invasion front. In conclusion, our findings show a very differential expression pattern of the four receptors in colorectal carcinomas and their corresponding liver metastases with prominent expression profiles that indicate a potential role in the pathogenesis of CRC.

Pancreatojejunal leakage after pancreas head resection: anatomic and surgeon-related factors

Leakage of pancreatojejunostomies after pancreatic resections remains a challenge even at high volume centers. We here utilized a simple pancreas anatomy classification to study the effect of pancreatic anatomy on the development of pancreatic fistula after pancreas resection and pancreatojejunostomies. Also, the effect of surgical experience on the development of pancreatic fistulas was studied. Three hundred ninety-one patients undergoing pancreatic resections and reconstruction with a pancreatojejunostomy were studied. Closed suction drain was placed behind the anastomosis, and drainage fluid was collected postoperatively. A twofold increase over the serum amylase level was considered a fistula and was classified as described by the International Study Group on Pancreatic Fistula Definition. In 67 patients, the structural quality of the pancreatic parenchyma and the diameter of the pancreatic duct were classified as being <2 mm (2 points), between 2 and 5 mm (1 point), or >5 mm (0 points). The pancreatic parenchyma was assessed as being soft (2 points), intermediate (1 point), or hard (0 points). Pancreatic leakage as a function of surgeons' experience was also studied. Leakage was found in 25.1%, 8.9% being of type A, 10.2% being of type B, and 5.9% of type C. Pancreatic fistulas were only observed in patients with a score of 2 points or more. Age over 70 years, operations >6 h, and extended lymphadenectomy or surgeons experience were not associated with a higher leakage rate. In this study, leakage after pancreatojejunostomy was only associated with pancreatic anatomy, classified with a simple score. That score might improve comparability of studies on pancreatic leakage. Furthermore, drainage of pancreatic anastomosis might safely be omitted in patients with a low risk score for leakage.

Hemoglobin induces cytotoxic damage of glycine-preserved renal tubules

In isolated tubular segments (ITS) of rat kidney cortex, we studied the effect of hemoglobin (Hb) on reoxygenation damage. All tubules were suspended in Ringer's solution containing 5-mm glycine and oxygenated for 30 min with 95% O(2):5% CO(2), followed by a 30-min period with 95% N(2):5% CO(2), and final reoxygenation for 60 min. Untreated tubules served as controls. Different concentrations of free Hb and equivalent amounts of intact erythrocytes were added to the incubation medium. Secondly, we added deferoxamine (DFO) to Hb and erythrocytes. Membrane leakage and lipid peroxidation were measured by lactate dehydrogenase and glutamate dehydrogenase and the development of thiobarbituric acid reactive substances. Cell function was quantified by gluconeogenesis and intracellular potassium accumulation. Hb exerted concentration-dependent cytotoxic effects indicated by significantly increased enzyme leakage rates, lipid peroxidation and a significantly decreased cell function (P < 0.05), in ITS during hypoxia, and subsequent reoxygenation. Moreover, we found that toxicity of both Fe(2+) and Fe(3+) ions increased with rising concentration. However, Fe(2+) showed a higher tissue toxicity than Fe(3+). DFO reduced significantly the reoxygenation damage of free Hb and iron ions. Our data clearly demonstrate a pronounced cytotoxic effect of free Hb in ITS, which critically depended on the reduction state of the iron ions.

Studies on MIP-2 and CXCR2 expression in a mouse model of extrahepatic colorectal metastasis

AIMS

The CXC chemokine macrophage inflammatory protein (MIP)-2 has been shown to promote outgrowth of colorectal liver metastasis by enhancing angiogenesis and tumor cell migration. However, the effect of MIP-2 on extrahepatic metastasis is not known yet. With a use of a murine model, we therefore studied cell proliferation and microvascularization of extrahepatic CT26.WT-GFP colorectal tumors after exposure to MIP-2.

METHODS

Green fluorescent protein (GFP)-transfected CT26.WT colorectal cancer cells were implanted in dorsal skinfold chambers of syngeneic BALB/c mice. After 5 days, the tumors were locally exposed to 100 nM MIP-2. Cell proliferation as well as tumor microvascularization and growth were studied during a further 9-day period using intravital fluorescence microscopy, histology and immunohistochemistry. Tumors exposed to PBS served as controls.

RESULTS

MIP-2 induced a marked CXCR2 expression and promoted a distinct tumor cell proliferation. This was associated with a significant increase of tumor size compared to PBS-treated controls. Of interest, MIP-2 did not affect dilation and permeability of the tumor microvessels, which would be indicators for an enhanced VEGF action. Accordingly, the angiogenic response, e.g. the outgrowth of new microvessels, was not affected, and the density of the established tumor microvascular network was even found decreased after MIP-2 exposure when compared to PBS controls.

CONCLUSION

With the use of a murine tumor model, we demonstrate that MIP-2 accelerates growth of experimentally established extrahepatic colorectal metastases by inducing tumor cell proliferation rather than promoting vascularization.

Efficacy and quality of vessel sealing

BACKGROUND

During the past few years, a variety of energy-based techniques for vessel ligation have been introduced. With the use of a porcine model and different devices for bipolar vessel sealing (BiClamp and LigaSure), we studied the impact of different clamp surface structures on the efficacy and quality of vessel sealing.

METHODS

Eight Swabian Hall pigs underwent splenectomy, nephrectomy, salpingo-oophorectomy, and small bowel resection with the use of bipolar vessel sealing devices designed for open and laparoscopic surgery. Vessel sealing with clamps with a smooth (nonstructured) surface (BiClamp for open surgery and LigaSure for laparoscopic surgery) was compared to that of clamps with a structured (grooved, wafer-like) surface (BiClamp for laparoscopic surgery and LigaSure for open surgery). Measurements of sealed vessels (2- to 7-mm diameter) included the seal failure rate, instrument sticking, and heat-associated morphological vascular wall alterations.

RESULTS

Analysis of seal failures did not reveal significant differences between the different devices for both open [BiClamp, 17.9% (17/95); LigaSure, 15.5% (11/71)] and laparoscopic surgery [BiClamp, 2.8% (1/36); LigaSure, 8.6% (3/35)]. Comparing all data of structured versus smooth clamp surfaces, the seal failure rate was lower using clamps with a structured (11.2%) compared to a smooth surface (15.4%). Instrument sticking and thermal spread were found to be significantly increased after sealing with structured surfaces, regardless of whether devices designed for open (p < 0.05 and p < 0.001, respectively) or laparoscopic surgery (p < 0.001 and p < 0.01, respectively) were used.

CONCLUSION

Clamps with a structured surface seem to be superior to those with a smooth surface for successful bipolar vessel sealing, as indicated by an increase of thermal spread. However, the more pronounced instrument sticking represents an undesired side effect and should encourage the search for more inert materials to further improve the sealing procedure.

[Esophageal resection with fundus rotation gastroplasty]

Esophageal resection with fundus rotation gastroplasty. Anastomotic failure after esophageal resection remains a surgical problem with high clinical relevance. Anastomotic failure can be attributed to tension at the anastomosis especially in cervical anastomoses, as well as a perfusion deficit due to resection of the arterial arcade along the gastric lesser curvature. We attributed the anatomical deficiencies of conventional gastroplasties by developing a technique, that utilizes the whole gastric fundus and maintains the arterial arcade along the gastric lesser curvature: fundus rotation gastroplasty. Experimentally those tubes are 20 % longer than conventional tubes according to Kirschner/Akiyama and twice as good perfused. Clinically low failure rates of 7 % for cervical and thoracic anastomoses are achieved.

The suprapubic approach for laparoscopic appendectomy

BACKGROUND

Because it produces superior cosmetic results, patients prefer laparoscopic appendectomy over open appendectomy. We developed two alternative laparoscopic routes of access to the abdominal cavity for appendectomy that use suprapubic incisions placed below the line of pubic hair. We then compared the results for these three different modes of access.

METHODS

Operative characteristics, morbidity, outcome, and patient preference regarding three different approaches to laparoscopic appendectomy were compared in a retrospective study. In addition, a group of 24 healthy women were surveyed by questionnaire about their preferred technique and expected cosmetic results.

RESULTS

Between January 1997 and August 2000, 149 patients underwent laparoscopic appendectomy and were assigned to undergo one of the three techniques. Operative results, morbidity, and hospital stay were similar. Twenty-five percent of patients submitted to technique 1 (no suprapubic trocars) were satisfied with their method, vs 54% of patients with technique 2 (one suprapubic port, angled working trocars) and 100% of patients with technique 3 (two suprapubic parallel trocars). Almost all patients (92% of those who had technique 1 and 100% of those who had techniques 2 and 3) chose the standard laparoscopic access as the cosmetically least attractive method. All of the healthy controls we interviewed preferred technique 3.

CONCLUSION

The placement of suprapubic trocars improves the surgeon's working position during laparoscopic appendectomy. A laparoscopic approach using two suprapubic trocars yields the best cosmetic results in the opinion of the majority of patients and healthy interviewees.

Primary vs. secondary anastomosis after sigmoid colon resection for perforated diverticulitis (Hinchey Stage III and IV): a prospective outcome and cost analysis

PURPOSE

Our hypothesis was that in patients with perforated sigmoid colon diverticulitis and peritonitis (Hinchey Stage III and IV) a one-stage sigmoid colon resection is safe and cost effective when performed by an experienced colorectal surgeon. We evaluated outcome and cost of one-stage vs. two-stage sigmoid colon resection after diverticulitis perforation and peritonitis.

METHODS

Patients undergoing emergency resection for perforated sigmoid colon diverticulitis and peritonitis (Hinchey Stage III and IV). Outcome, costs, and insurers reimbursement were compared between 13 patients undergoing sigmoid colon resection and primary anastomosis (Group A) and 42 patients undergoing sigmoid colon resection with Hartmann's procedure and secondary descendorectostomy (Group B).

RESULTS

Group A patients were comparable to Group B patients in age, gender, preoperative risk and severity of peritonitis (Mannheim Peritonitis Index and C-reactive protein). Operating room time for sigmoid colon resection with primary anastomosis (3.3 +/- 1.2 hours) was identical to the time for sigmoid colon resection with colostomy (3.3 +/- 1 hour), and morbidity and mortality, intensive care unit, and in-hospital stay were not significantly different between the two groups. In Group B patients' intestinal continuity was restored 169 +/- 74 days after the primary resection in 32 of 42 patients only (78 percent). The second procedure took on average 1.4 hours longer than the first procedure. Patients in Group B received more antibiotics (2.2 vs. 2) albeit for a shorter period of time (4.5 vs. 5.7 days, P = not significant). Overall expenses for restoration of intestinal continuity were between 74 and 229 percent higher for Group B patients than for Group A patients. Reimbursement was 18,191 +/- 16,761 SFr (Group A) and 41,321 +/- 26,983 SFr (Group B) respectively.

CONCLUSION

With meticulous surgical technique and extensive intraoperative lavage, perforated sigmoid colon diverticulitis with peritonitis can be treated by a one-stage sigmoid colon resection and anastomosis with a low mortality and morbidity. A one-stage procedure is considerably cheaper and patients are rehabilitated faster and to a higher percentage.

Liver transplantation after organ preservation with normothermic extracorporeal perfusion

OBJECTIVE

To study normothermic extracorporeal liver perfusion (NELP) as a means to preserve livers for transplantation and to reverse warm ischemic injury.

SUMMARY BACKGROUND DATA

The authors provide experimental evidence that successful transplantation after 4 hours of normothermic extracorporeal liver perfusion is possible and as reliable as 4 hours of cold preservation in University of Wisconsin solution. NELP preserves liver function completely and can reverse 60 minutes of warm ischemic injury in non-heart-beating donors.

METHODS

Thirty-six German Landrace pigs received transplants in six groups. Group 1 animals received direct transplantation. Group 2 received transplants after 4 hours of cold preservation with University of Wisconsin solution and Group 3 animals after 4 hours of NELP. Group 4 animals sustained 1 hour of warm ischemia before transplantation. Group 5 animals received transplants after 1 hour of warm ischemia and 4 hours of cold preservation and Group 6 animals after 1 hour of warm ischemia and 4 hours of NELP.

RESULTS

All animals receiving livers treated by NELP survived more than 7 days after the transplant (Groups 3 and 6). In contrast, all animals in Group 5 developed primary graft nonfunction within 24 hours after transplantation.

CONCLUSION

The technique of NELP holds the potential to keep a mammalian liver outside the body completely functional, possibly for more than 4 hours. NELP can be used for liver preservation before transplantation or for the use of organs from non-heart-beating donors.

Treatment of chyloperitoneum after extended lymphatic dissection during duodenopancreatectomy

BACKGROUND

Chyloperitoneum is a rare postoperative complication that might be caused by an interruption of chylous ducts in the mesenteric root or the cysterna chyli. Two cases of chyloperitoneum after duodenopancreatectomy are reported in the literature.

METHODS

We here report the third case that developed a chyloperitoneum 2 wk postoperatively when he resumed his normal diet.

RESULTS

The patient was treated conservatively with paracenteses and chyloperitoneum subsided thereafter.

CONCLUSIONS

Chyloperitoneum after extended duodenopancreatectomy might be treated conservatively.