Right Hepatectomy in Patients over 70 Years of Age: An Analysis of Liver Function and Outcome

Background: As a consequence of the increase in life expectancy, hepatobiliary surgeons have to deal with an emerging aged population. We aimed to analyze the liver function and outcome after right hepatectomy (RH) in patients over 70years of age. Methods: From January 2006 to December 2009, we prospectively collected data of 207 consecutive elective hepatectomies. In patients who had RH, cardiac risk was assessed by a dedicated preoperative workup. Liver failure (LF) was defined by the "fifty-fifty” criteria at postoperative day 5 (POD) and morbidity by the Clavien-Dindo classification. Liver function tests (LFTs) and short-term outcome were retrospectively analyzed in patients over (elderly group, EG) and younger (young group, YG) than 70years of age. Results: Eighty-seven consecutive RH were performed during the study period. Indication for surgery included 90% malignancy in 47% of patients requiring preoperative chemotherapy. ASA grade>2 (44 vs. 16%, p=0.027), ischemic heart disease (17 vs. 5%, p=0.076), and preoperative cardiac failure (26 vs. 2%, p<0.001) were more frequent in the EG (n=23) than in the YG (n=64). Both groups were similar regarding rates of normal liver parenchyma, chemotherapy and intraoperative parameters. The overall morbidity rates were comparable, but the serious complication (grades III-V) rate was relatively higher in the EG (39 vs. 25%, p=0.199), particularly in patients with diabetes mellitus (100 vs. 29%, p=0.04) and those who had additional nonhepatic surgery (67 vs. 35%, p=0.110) and transfusions (44 vs. 30%, p=0.523). The 90-day mortality rate was similar (9% in the EG vs. 3% in the YG, p=0.28) and was related to heart failure in the EG. LFTs showed a similar trend from POD 1 to 8, and patients ≥70years of age had no liver failure. Conclusions: Age ≥70years alone is not a contraindication to RH. However, major morbidity is particularly higher in the elderly with diabetes. This high-risk group should be closely monitored in the postoperative course. Liver function is not altered in the elderly patient after R

Liver transplant outcomes after ex vivo machine perfusion: a meta-analysis

Background: The pressure on liver-transplant programmes has expanded the usage of extended-criteria allografts. Machine perfusion may be better than conventional static cold storage (SCS) in alleviating ischaemia-reperfusion injury in this setting. Recipient outcomes with hypothermic or normothermic machine perfusion were assessed against SCS here. Methods: A search in MEDLINE, EMBASE and Scopus was conducted in February 2021. Primary studies investigating ex vivo machine perfusion were assessed for the following outcomes: morbidity, ICU and hospital stay, graft and patient survival rates and relative costs. Meta-analysis was performed to obtain pooled summary measures. Results: Thirty-four articles involving 1742 patients were included, of which 20 were used for quantitative synthesis. Odds ratios favoured hypothermic machine perfusion (over SCS) with less early allograft dysfunction, ischaemic cholangiopathy, non-anastomotic strictures and graft loss. Hypothermic machine perfusion was associated with a shorter hospital stay and normothermic machine perfusion with reduced graft injury. Two randomized clinical trials found normothermic machine perfusion reduced major complication risks. Conclusion: Machine perfusion assists some outcomes with potential cost savings

Quantification of liver iron content with CT—added value of dual-energy

Objective: To evaluate the value of dual-energy CT (DECT) with use of an iron-specific, three-material decomposition algorithm for the quantification of liver iron content (LIC). Methods: Thirty-one phantoms containing liver tissue, fat and iron were scanned with dual-source CT using single-energy at 120kV (SECT) and DECT at 80kV and 140kV. Virtual iron concentration (VIC) images derived from an iron-specific, three-material decomposition algorithm and measurements of fat-free and fat-containing phantoms were compared with the LIC and healthy liver tissue. Results: In the absence of fat significant linear correlations were found between LIC and HU from SECT and VIC (r = 0.984-0.997, p  0.632). Conclusions: Virtual iron concentration images generated from DECT provide added value for the quantification of LIC by disregarding the confounding effect of the natural variation of healthy liver attenuation and of co-existing liver fa

Dixon-based MRI for assessment of muscle-fat content in phantoms, healthy volunteers and patients with achillodynia: comparison to visual assessment of calf muscle quality

Objectives: To quantify the muscle fat-content (MFC) in phantoms, volunteers and patients with achillodynia using two-point Dixon-based magnetic resonance imaging (2pt-MRIDIXON) in comparison to MR spectroscopy (MRS) and visual assessment of MFC. Methods: Two-point Dixon-based MRI was used to measure the MFC of 15 phantoms containing 0-100% fat-content and calf muscles in 30 patients (13 women; 57 ± 15years) with achillodynia and in 20 volunteers (10 women; 30 ± 14years) at 1.5T. The accuracy of 2pt-MRIDIXON in quantification of MFC was assessed in vitro using phantoms and in vivo using MRS as the standard of reference. Fat-fractions derived from 2pt-MRIDIXON (FFDIXON) and MRS (FFMRS) were related to visual assessment of MFC (Goutallier grades 0-4) and Achilles-tendon quality (grade 0-4). Results: Excellent linear correlation was demonstrated for FFDIXON with phantoms and with FFMRS in patients (p c = 0.997/0.995; p  0.05). FFMRS and FFDIXON were significantly higher in subjects with (>grade 1) structural damage of the Achilles-tendon (p = 0.01). Conclusions: Two-point Dixon-based MRI allows for accurate quantification of MFC, outperforming visual assessment of calf muscle fat. Structural damage of the Achilles tendon is associated with a significantly higher MFC. Key points: • Two-point Dixon-based MRI allows accurate quantification of muscular fat content (MFC). • Quantitative analysis outperforms visual analysis in the detection of elevated MFC. • Achillodynia results in an increased MFC of the gastrocnemius muscles. • Structural damage of the Achilles tendon further increases the MFC

Pre-Emptive Endoluminal Negative Pressure Therapy at the Anastomotic Site in Minimally Invasive Transthoracic Esophagectomy (the preSPONGE Trial): Study Protocol for a Multicenter Randomized Controlled Trial

Introduction: Anastomotic leakage (AL) accounts for a significant proportion of morbidity following oesophagectomy. Endoluminal negative pressure (ENP) therapy via a specifically designed polyurethane foam (EsoSponge®, B.Braun Medical, Melsungen, Germany) has become the standard of care for AL in many specialized centres. The prophylactic (pENP) application of this technique aims to reduce postoperative morbidity and is a novel approach which has not yet been investigated in a prospective study. The aim of this study is therefore to assess the effect of pENP at the anastomotic site in high-risk patients undergoing minimally invasive transthoracic Ivor Lewis oesophagectomy. Methods and analysis: The study design is a prospective, multi-centre, two-arm, parallel-group, randomised controlled trial and will be conducted in two phases. Phase one is a randomised feasibility and safety pilot trial involving 40 consecutive patients. After definitive sample size calculation, additional patients will be included accordingly during phase two. The primary outcome of the study will be the postoperative length of hospitalization until reaching previously defined “fit for discharge criteria”. Secondary outcomes will include postoperative morbidity, mortality and postoperative AL-rates based on 90-day follow-up. A confirmatory analysis based on intention-to-treat will be performed. Ethics and dissemination: The ethics committee of the University of Zurich approved this study (2019-00562), which has been registered with ClinicalTrials.gov on 14.11.2019 (NCT04162860) and the Swiss National Clinical Trials Portal (SNCTP000003524). The results of the study will be published and presented at appropriate conferences

Diagnosis of Fault Modes Masked by Control Loops with an Application to Autonomous Hovercraft Systems

This paper introduces a methodology for the design, testing and assessment of incipient failure detection techniques for failing components/systems of an autonomous vehicle masked or hidden by feedback control loops. It is recognized that the optimum operation of critical assets (aircraft, autonomous systems, etc.) may be compromised by feedback control loops by masking severe fault modes while compensating for typical disturbances. Detrimental consequences of such occurrences include the inability to detect expeditiously and accurately incipient failures, loss of control and inefficient operation of assets in the form of fuel overconsumption and adverse environmental impact. We pursue a systems engineering process to design, construct and test an autonomous hovercraft instrumented appropriately for improved autonomy. Hidden fault modes are detected with performance guarantees by invoking a Bayesian estimation approach called particle filtering. Simulation and experimental studies are employed to demonstrate the efficacy of the proposed methods

Access to a Simulator is Not Enough: The Benefits of Virtual Reality Training Based on Peer-Group-Derived Benchmarks—A Randomized Controlled Trial

Background: Virtual reality (VR) simulators are widely used to familiarize surgical novices with laparoscopy, but VR training methods differ in efficacy. In the present trial, self-controlled basic VR training (SC-training) was tested against training based on peer-group-derived benchmarks (PGD-training). Methods: First, novice laparoscopic residents were randomized into a SC group (n=34), and a group using PGD-benchmarks (n=34) for basic laparoscopic training. After completing basic training, both groups performed 60 VR laparoscopic cholecystectomies for performance analysis. Primary endpoints were simulator metrics; secondary endpoints were program adherence, trainee motivation, and training efficacy. Results: Altogether, 66 residents completed basic training, and 3,837 of 3,960 (96.8%) cholecystectomies were available for analysis. Course adherence was good, with only two dropouts, both in the SC-group. The PGD-group spent more time and repetitions in basic training until the benchmarks were reached and subsequently showed better performance in the readout cholecystectomies: Median time (gallbladder extraction) showed significant differences of 520s (IQR 354-738s) in SC-training versus 390s (IQR 278-536s) in the PGD-group (p<0.001) and 215s (IQR 175-276s) in experts, respectively. Path length of the right instrument also showed significant differences, again with the PGD-training group being more efficient. Conclusions: Basic VR laparoscopic training based on PGD benchmarks with external assessment is superior to SC training, resulting in higher trainee motivation and better performance in simulated laparoscopic cholecystectomies. We recommend such a basic course based on PGD benchmarks before advancing to more elaborate VR trainin

Cosmesis and body image after single-port laparoscopic or conventional laparoscopic cholecystectomy: a multicenter double blinded randomised controlled trial (SPOCC-trial)

BACKGROUND: Emerging attempts have been made to reduce operative trauma and improve cosmetic results of laparoscopic cholecystectomy. There is a trend towards minimizing the number of incisions such as natural transluminal endoscopic surgery (NOTES) and single-port laparoscopic cholecystectomy (SPLC). Many retrospective case series propose excellent cosmesis and reduced pain in SPLC. As the latter has been confirmed in a randomized controlled trial, patient's satisfaction on cosmesis is still controversially debated. METHODS/DESIGN: The SPOCC trial is a prospective, multi-center, double blinded, randomized controlled study comparing SPLC with 4-port conventional laparoscopic cholecystectomy (4PLC) in elective surgery. The hypothesis and primary objective is that patients undergoing SPLC will have a better outcome in cosmesis and body image 12 weeks after surgery. This primary endpoint is assessed using a validated 8-item multiple choice type questionnaire on cosmesis and body image. The secondary endpoint has three entities: the quality of life 12 weeks after surgery assessed by the validated Short-Form-36 Health Survey questionnaire, postoperative pain assessed by a visual analogue scale and the use of analgesics. Operative time, surgeon's experience with SPLC and 4PLC, use of additional ports, conversion to 4PLC or open cholecystectomy, length of stay, costs, time of work as well as intra- and postoperative complications are further aspects of the secondary endpoint. Patients are randomly assigned either to SPLC or to 4PLC. Patients as well as treating physicians, nurses and assessors are blinded until the 7th postoperative day. Sample size calculation performed by estimating a difference of cosmesis of 20% (alpha = 0.05 and beta = 0.90, drop out rate of 10%) resulted in a number of 55 randomized patients per arm. DISCUSSION: The SPOCC-trial is a prospective, multi-center, double-blind, randomized controlled study to assess cosmesis and body image after SPLC

Assessing the Value of Prehabilitation in Patients Undergoing Colorectal Surgery According to the Enhanced Recovery After Surgery (ERAS) Pathway for the Improvement of Postoperative Outcomes: Protocol for a Randomized Controlled Trial

A key element in the postoperative phase of the standardized Enhanced Recovery After Surgery (ERAS) treatment pathways is mobilization. Currently, there are no recommendations in the ERAS guidelines for preoperative physical activity. Patients undergoing major surgery are prone to functional decline due to the impairment of muscle, cardiorespiratory, and neurological function as a response to surgical stress. It has been shown that preoperative physical training reduces postoperative complications. To date, there are limited studies that investigate preoperative physical training combined with ERAS