Does Comprehensive Geriatric Assessment Reduce the Incidence of Postoperative Delirium? A Quasi-experimental Study in Older Adults Undergoing Transcatheter Aortic Valve Implantation.

Purpose: Postoperative delirium (POD) after transcatheter aortic valve implantation (TAVI) is frequent in older adults and associated with multiple negative outcomes including a higher mortality. We aimed to investigate whether a comprehensive geriatric assessment (CGA) prior to TAVI reduces the odds of POD and results in a positive change in self-care ability, intended to lay a foundation for future geriatric comanagement. Patients and methods: We used a retrospective, single-center study with a quasi-experimental design enrolling patients aged 70 years and older undergoing CGA before elective TAVI, and a nonrandomized comparison group without preoperative CGA. Data on POD occurrence during the first 5 days after TAVI (primary outcome) and change in self-care ability index (SPI) between admission and discharge (secondary outcome) were collected from electronic health records and CGA data (exposure) by clinical assessment. To explore associations between (1) CGA and POD, and (2) CGA and SPI, multivariate logistic regression and linear regression models were applied adjusting for age, sex, BMI, and number of medications. Results: Among 435 patients (mean age 81.0 ± 5.6 years, 43.6% women, median [IQR] SPI at baseline 40 [39, 40] points), POD incidence was 14.3% in the CGA group vs 18.8% in the non-CGA group (P 0.219). Undergoing CGA before TAVI was not associated with the odds for POD (OR: 1.15; 95%CI: 0.65-2.04) or improved SPI (P 0.073). Conclusion: We observed no association of CGA prior to TAVI with POD incidence or postoperative self-care, highlighting the need for additional studies investigating the effect of POD preventive measures in older TAVI patients integrated into a comprehensive geriatric comanagement program.

A Descriptive Analysis of Hybrid Cannulated Extracorporeal Life Support.

BACKGROUND: Extracorporeal life support (ECLS) is pivotal for sustaining the function of failing hearts and lungs, and its utilization has risen. In cases where conventional cannulation strategies prove ineffective for providing adequate ECLS support, the implementation of an enhanced system with a third cannula may become necessary. Hybrid ECLS may be warranted in situations characterized by severe hypoxemia of the upper extremity, left ventricular congestion, and dilatation. Additionally, it may also be considered for patients requiring respiratory support or experiencing hemodynamic instability. METHOD: All hybrid ECLS cases of adults at the University Hospital Zurich, Switzerland, between January 2007 and December 2019 with initial triple cannulation were included. Data were collected via a retrospective review of patient records and direct export of the clinical information system. RESULTS: 28 out of 903 ECLS cases were initially hybrid cannulated (3.1%). The median age was 57 (48.2 to 60.8) years, and the sex was equally distributed. The in-hospital mortality of hybrid ECLS was high (67.9%). In-hospital mortality rates differ depending on the indication (ARDS: 36.4%, refractory cardiogenic shock: 88.9%, cardiopulmonary resuscitation: 100%, post-cardiotomy: 100%, others: 75%). Survivors exhibited a lower SAPS II level compared with non-survivors (20.0 (12.0 to 65.0) vs. 55.0 (45.0 to 73.0)), and the allogenic transfusion of platelet concentrate was observed to be less frequent for survivors (0.0 (0.0) vs. 1.8 (2.5) units). CONCLUSION: The in-hospital mortality rate for hybrid ECLS was high. Different indications showed varying mortality rates, with survivors having lower SAPS II scores and requiring fewer platelet concentrate transfusions. These findings highlight the complexities of hybrid ECLS outcomes in different clinical scenarios and underline the importance of rigorous patient selection.

How to counteract the lack of donor tissue in cardiac surgery? Initial experiences with a newly established homograft procurement program.

Homograft heart valves may have significant advantages and are preferred for the repair of congenital valve malformations, especially in young women of childbearing age, athletes and in patients with active endocarditis. A growing problem, however, is the mismatch between tissue donation and the increasing demand. The aim of this paper is to describe the initiation process of a homograft procurement program to attenuate the shortage of organs. A comprehensive description of the infrastructure and procedural steps required to initiate a cardiac and vascular tissue donation program combined with a prospective follow-up of all homografts explanted at our institution. Between January 2020 and May 2022, 28 hearts and 12 pulmonary bifurcations were harvested at our institution and delivered to the European homograft bank. Twenty-seven valves (19 pulmonary valves, 8 aortic valves) were processed and allocated for implantation. The reasons for discarding a graft were either contamination (n = 14), or morphology (n = 13) or leaflet damage (n = 2). Five homografts (3 PV, 2 AV) have been cryopreserved and stored while awaiting allocation. One pulmonary homograft with a leaflet cut was retrieved by bicuspidization technique and awaits allocation, as a highly requested small diameter graft. The implementation of a tissue donation program in cooperation with a homograft bank can be achieved with reasonable additional efforts at a transplant center with an in-house cardiac surgery department. Challenging situations with a potential risk of tissue injury during procurement include re-operation, harvesting by a non-specialist surgeon and prior central cannulation for mechanical circulatory support.

Inter-institutional analysis of the outcome after postcardiotomy veno-arterial extracorporeal membrane oxygenation.

INTRODUCTION: Patients requiring postcardiotomy veno-arterial extracorporeal membrane oxygenation (V-A-ECMO) have a high risk of early mortality. In this analysis, we evaluated whether any interinstitutional difference exists in the results of postcardiotomy V-A-ECMO. METHODS: Studies on postcardiotomy V-A-ECMO were identified through a systematic review for individual patient data (IPD) meta-analysis. Analysis of interinstitutional results was performed using direct standardization, estimation of observed/expected in-hospital mortality ratio and propensity score matching. RESULTS: Systematic review of the literature yielded 31 studies. Data from 10 studies on 1269 patients treated at 25 hospitals were available for the present analysis. In-hospital mortality was 66.7%. The relative risk of in-hospital mortality was significantly higher in six hospitals. Observed versus expected in-hospital mortality ratio showed that four hospitals were outliers with significantly increased mortality rates, and one hospital had significantly lower in-hospital mortality rate. Participating hospitals were classified as underperforming and overperforming hospitals if their observed/expected in-hospital mortality was higher or lower than 1.0, respectively. Among 395 propensity score matched pairs, the overperforming hospitals had significantly lower in-hospital mortality (60.3% vs 71.4%, p = 0.001) than underperforming hospitals. Low annual volume of postcardiotomy V-A-ECMO tended to be predictive of poor outcome only when adjusted for patients' risk profile. CONCLUSIONS: In-hospital mortality after postcardiotomy V-A-ECMO differed significantly between participating hospitals. These findings suggest that in many centers there is room for improvement of the results of postcardiotomy V-A-ECMO.

Predicting Survival for Veno-Arterial ECMO Using Conditional Inference Trees-A Multicenter Study.

BACKGROUND: Despite increasing use and understanding of the process, veno-arterial extracorporeal membrane oxygenation (VA-ECMO) therapy is still associated with considerable mortality. Personalized and quick survival predictions using machine learning methods can assist in clinical decision making before ECMO insertion. METHODS: This is a multicenter study to develop and validate an easy-to-use prognostic model to predict in-hospital mortality of VA-ECMO therapy, using unbiased recursive partitioning with conditional inference trees. We compared two sets with different numbers of variables (small and comprehensive), all of which were available just before ECMO initiation. The area under the curve (AUC), the cross-validated Brier score, and the error rate were applied to assess model performance. Data were collected retrospectively between 2007 and 2019. RESULTS: 837 patients were eligible for this study; 679 patients in the derivation cohort (median (IQR) age 60 (49 to 69) years; 187 (28%) female patients) and a total of 158 patients in two external validation cohorts (median (IQR) age 57 (49 to 65) and 70 (63 to 76) years). For the small data set, the model showed a cross-validated error rate of 35.79% and an AUC of 0.70 (95% confidence interval from 0.66 to 0.74). In the comprehensive data set, the error rate was the same with a value of 35.35%, with an AUC of 0.71 (95% confidence interval from 0.67 to 0.75). The mean Brier scores of the two models were 0.210 (small data set) and 0.211 (comprehensive data set). External validation showed an error rate of 43% and AUC of 0.60 (95% confidence interval from 0.52 to 0.69) using the small tree and an error rate of 35% with an AUC of 0.63 (95% confidence interval from 0.54 to 0.72) using the comprehensive tree. There were large differences between the two validation sets. CONCLUSIONS: Conditional inference trees are able to augment prognostic clinical decision making for patients undergoing ECMO treatment. They may provide a degree of accuracy in mortality prediction and prognostic stratification using readily available variables.

Predictors associated with mortality of veno-venous extracorporeal membrane oxygenation therapy.

Background: The use of veno-venous extracorporeal membrane oxygenation (V-V ECMO) has rapidly increased in recent years. Today, applications of V-V ECMO include a variety of clinical conditions such as acute respiratory distress syndrome (ARDS), bridge to lung transplantation and primary graft dysfunction after lung transplantation. The purpose of the present study was to investigate in-hospital mortality of adult patients undergoing V-V ECMO therapy and to determine independent predictors associated with mortality. Methods: This retrospective study was conducted at the University Hospital Zurich, a designated ECMO center in Switzerland. Data was analyzed of all adult V-V ECMO cases from 2007 to 2019. Results: In total, 221 patients required V-V ECMO support (median age 50 years, 38.9% female). In-hospital mortality was 37.6% and did not statistically vary significantly between indications (P=0.61): 25.0% (1/4) for primary graft dysfunction after lung transplantation, 29.4% (5/17) for bridge to lung transplantation, 36.2% (50/138) for ARDS and 43.5% (27/62) for other pulmonary disease indications. Cubic spline interpolation showed no effect of time on mortality over the study period of 13 years. Multiple logistic regression modelling identified significant predictor variables associated with mortality: age [odds ratio (OR), 1.05; 95% confidence interval (CI): 1.02-1.07; P=0.001], newly detected liver failure (OR, 4.83; 95% CI: 1.27-20.3; P=0.02), red blood cell transfusion (OR, 1.91; 95% CI: 1.39-2.74; P<0.001) and platelet concentrate transfusion (OR, 1.93; 95% CI: 1.28-3.15; P=0.004). Conclusions: In-hospital mortality of patients receiving V-V ECMO therapy remains relatively high. Patients' outcomes have not improved significantly in the observed period. We identified age, newly detected liver failure, red blood cell transfusion and platelet concentrate transfusion as independent predictors associated with in-hospital mortality. Incorporating such mortality predictors into decision making with regards to V-V ECMO use may increase its effectiveness and safety and may translate into better outcomes.

[Benefit of a Geriatric Evaluation before Operations, Interventions and Oncological Therapies]. / Nutzen altersmedizinischer Abklärungen vor Operationen, Interventionen und onkologischen Therapien.

Benefit of a Geriatric Evaluation before Operations, Interventions and Oncological Therapies Abstract: Older patients face an increased risk of complications and adverse outcomes during and after operations, interventions, and intense oncological therapies. At the same time, this patient group should not be excluded per se from potentially beneficial medical procedures based on chronological age alone. The timely identification of geriatric syndromes and increased vulnerability by means of comprehensive geriatric assessment is becoming increasingly important and is already recommended in the guidelines of professional societies of several medical disciplines. Nonetheless, the geriatric assessment should ideally be followed by proactive co-management in the sense of integrated care. The establishment of interdisciplinary and integrated care pathways for older hospital patients can contribute to significantly improved treatment outcomes. In addition to better patient-related outcomes and rising quality indicators, this approach may also offer positive health economic effects.

The impact of right ventricular hemodynamics on the performance of a left ventricular assist device in a numerical simulation model.

OBJECTIVES: Left ventricular assist devices (LVADs) have been established as alternative to heart transplantation for patients with end-stage heart failure refractory to medical therapy. Right heart failure (RHF) after LVAD implantation is associated with inferior outcome. Its preoperative anticipation may influence the selection between a pure left ventricular and a biventricular device type and, thus, improve outcomes. Reliable algorithms to predict RHF are missing. METHODS: A numerical model was used for simulation of a cardiovascular circulation. The LVAD was placed as parallel circuit between left ventricle and aorta. In contrast to other studies, the dynamic hydraulic behavior of a pulsatile LVAD was replaced by that of a continuous LVAD. A variety of hemodynamic states was tested mimicking different right heart conditions. Adjustable parameters included heart rate (HR), pulmonary vascular resistance (PVR), tricuspid regurgitation (TR), right ventricular contractility (RVC) and pump speed. Outcome parameters comprised central venous pressure (CVP), mean pulmonary artery pressure (mPAP), cardiac output (CO) and occurrence of suction. RESULTS: Alteration of HR, PVR, TR, RVC and pump speed resulted in diverse effects on CO, CVP and mPAP, resulting in improvement, impairment or no change of the circulation, depending on the degree of alteration. CONCLUSIONS: The numerical simulation model allows prediction of circulatory changes and LVAD behaviour following variation of hemodynamic parameters. Such a prediction may be of particular advantage to anticipate RHF after LVAD implantation. It may help preoperatively to choose the appropriate strategy of only left ventricular or both left and right ventricular support.

Long-distance donor heart procurement using an innovative cold static storage system.

The global lack of donor shortage poses a major limitation for heart transplantation. New concepts with expanded donor inclusion criteria comprise extended transport distances and prolonged ischemic times with the aim of reaching a larger number of potential donors. Recent developments in cold storage solutions may allow more donor hearts with prolonged ischemic times to be use for transplantation in the future. We present our experience during a long-distance donor heart procurement with the longest reported transport distance and transport time in the current literature. This was made possible through the use of SherpaPak™, an innovative cold storage system which allows for controlled temperatures during transportation.

Central versus Peripheral Postcardiotomy Veno-Arterial Extracorporeal Membrane Oxygenation: Systematic Review and Individual Patient Data Meta-Analysis.

BACKGROUND: It is unclear whether peripheral arterial cannulation is superior to central arterial cannulation for postcardiotomy veno-arterial extracorporeal membrane oxygenation (VA-ECMO). METHODS: A systematic review was conducted using PubMed, Scopus, and Google Scholar to identify studies on postcardiotomy VA-ECMO for the present individual patient data (IPD) meta-analysis. Analysis was performed according to the intention-to-treat principle. RESULTS: The investigators of 10 studies agreed to participate in the present IPD meta-analysis. Overall, 1269 patients were included in the analysis. Crude rates of in-hospital mortality after central versus peripheral arterial cannulation for VA-ECMO were 70.7% vs. 63.7%, respectively (adjusted OR 1.38, 95% CI 1.08-1.75). Propensity score matching yielded 538 pairs of patients with balanced baseline characteristics and operative variables. Among these matched cohorts, central arterial cannulation VA-ECMO was associated with significantly higher in-hospital mortality compared to peripheral arterial cannulation VA-ECMO (64.5% vs. 70.8%, p = 0.027). These findings were confirmed by aggregate data meta-analysis, which showed that central arterial cannulation was associated with an increased risk of in-hospital mortality compared to peripheral arterial cannulation (OR 1.35, 95% CI 1.04-1.76, I2 21%). CONCLUSIONS: Among patients requiring postcardiotomy VA-ECMO, central arterial cannulation was associated with an increased risk of in-hospital mortality compared to peripheral arterial cannulation. This increased risk is of limited magnitude, and further studies are needed to confirm the present findings and to identify the mechanisms underlying the potential beneficial effects of peripheral VA-ECMO.

Predictors associated with mortality of extracorporeal life support therapy for acute heart failure: single-center experience with 679 patients.

Background: Extracorporeal life support (ECLS) therapy is increasingly used for cardiac and respiratory support postcardiotomy, refractory cardiogenic shock and cardiopulmonary resuscitation. This study aims to describe in-hospital mortality of patients requiring ECLS, identify independent predictors associated with mortality and analyze changes of mortality over time. Methods: This retrospective study includes all adult ECLS cases at the University Hospital Zurich, a designated ECLS center in Switzerland, in the period 2007 to 2019. Results: ECLS therapy was required in 679 patients (median age 60 years, 27.5% female). In-hospital mortality was 55.5%. Cubic spline interpolation did not detect evidence for a change in mortality over the whole period of 13 years. In-hospital mortality significantly varied between ECLS indications: 70.7% (152/215) for postcardiotomy, 67.9% (108/159) for cardiopulmonary resuscitation, 47.0% (110/234) for refractory cardiogenic shock, and 9.9% (7/71) for lung transplantation and expansive thoracic surgery (P<0.001). Logistic regression modelling showed excellent discrimination in the receiver operating characteristic (ROC) area under the curve (AUC) of 0.89 [95% confidence interval (CI): 0.87-0.92] and identified significant mortality predictors: age, simplified acute physiology score (SAPS) II, as well as new liver failure and each allogenic blood transfusion unit given per day. ECLS after cardiopulmonary resuscitation was associated with significantly higher mortality compared to ECLS for refractory cardiogenic shock. Conclusions: In-hospital mortality of patients treated with ECLS therapy is high. Outcomes have not changed significantly in the observed period. We identified age, SAPS II, new liver failure and each allogenic blood transfusion unit given per day as independent mortality predictors. Knowledge of predictors strongly associated with in-hospital mortality may affect future decisions about ECLS indications and the respective management to use this elaborate therapy more effectively.

Acute limb ischemia after femoro-femoral extracorporeal life support implantation: A comparison of surgical, percutaneous, or combined vascular access in 402 patients.

BACKGROUND: Extracorporeal life support (ECLS) is a salvage treatment for acute circulatory failure. Our high-volume tertiary centre performs more than 100 implants annually and provides ECLS-transports. With this study, we aimed to analyze the incidence and risk factors of limb ischemia depending on the vascular access. METHODS: Between January 1, 2007, and December 31, 2018, 937 patients received an ECLS. Preoperative, intraoperative, in-hospital and up to 5 years follow-up data were collected. Outcome measures were limb ischemia and survival. RESULTS: In total, 402 femoro-femoral veno-arterial ECLS patients were identified. Mean age was 56 ± 16.7 years, 26.9% were female, 7.9% had a history of peripheral vascular disease. Cannulation was performed percutaneously in 82.1% (n = 330), surgically in 5.7% (n = 23) and combined in 12.2% (n = 49). Mortality was not significantly different between the groups (51.1% percutaneous, 43.5% surgical, 44.9% combined [p = 0.89]). There was no significant difference in limb ischemia either, but a trend toward an increased frequency in the percutaneous group (p = 0.0501). No amputation was necessary. Limb ischemia slightly increased in-hospital mortality (54.6%) but did not affect long-term survival beyond 30 days. Univariate analysis adjusted for cannulation methods revealed younger age and female gender as risk factors of limb ischemia and younger age for limb ischemia after percutaneous cannulation. CONCLUSIONS: Our study shows that percutaneous, surgical, and combined vascular access techniques for ECLS implantation are associated with comparable and low incidence of limb ischemia which slightly increases in-hospital mortality. Special precaution has to be taken in young and female patients.

The use of serotonin reuptake inhibitors increases the risk of bleeding in patients with assist devices.

BACKGROUND: Bleedings are frequent and dreaded complications in heart failure patients with ventricular assist devices (VAD). Serotonin reuptake inhibitor (SRI) antidepressants are widely used to treat depression in these patients, though they are attributed an increased risk of bleeding due to their modification of hemostasis. Evidence on bleeding risk of VAD patients under SRI medication is scarce and limited. We therefore aimed to assess if SRI use is associated with an elevated bleeding risk in this particularly vulnerable population. METHODS: We analyzed the medical records of 92 VAD patients at the University Heart Center Zurich between September 2004 and April 2018 for the occurrence of bleedings and the concomitant use of an SRI. Bleeding was defined as any type of post-implantation bleeding requiring medical treatment. We performed univariate analyses and linear mixed-effects models, adjusting for baseline clinical characteristics as potential predictors to identify differences in bleeding rates in patients with vs. without SRI intake. RESULTS: The cohort comprised 60.9% of patients with a continuous-flow VAD and 39.1% with a pulsatile-flow VAD. A total of 77.2% of patients experienced at least one bleeding incident. Overall, 28.6% of bleedings occurred under SRI therapy. A generalized linear mixed model showed a predictive effect of SRI medication on bleeding rate, independent of VAD type (z = 2.091, p = 0.037). CONCLUSIONS: Bleeding events in heart failure patients occur frequently after VAD implantation. Patients with SRI medication were at increased risk of bleeding. The indication and use of SRI, therefore, should be considered carefully.

Cardiac Rehabilitation in Patients With Ventricular Assist Device.

PURPOSE: The aim of this study was to investigate changes in exercise capacity (EC) and quality of life (QoL) of patients with ventricular assist devices (VADs) during cardiac rehabilitation (CR). METHODS: Data from patients with VAD implantation and subsequent CR between 2007 and 2017 were analyzed retrospectively. Measures of the 6-min walk test [6MWT] distance, Functional Independence Measure [FIM], ergometry, MacNew Heart Disease Questionnaire [MNH], and Hospital Anxiety and Depression Scale [HADS] at entry and discharge were examined. RESULTS: Data from 110 patients (age 53 ± 12 yr; male 82%) were analyzed. Patients improved during CR significantly in the 6MWT (114 ± 85 m, P < .001), ergometry (20 ± 17 W, P = .002), FIM (8 ± 7 points, P < .001), and MNH (0.8 ± 0.7 points, P < .001). Initial HADS levels were high with a mean value of 9 and did not improve during CR (-0.4 ± 5 points, P = .637). Significant differences of improvements in the 6MWT were observed between left and biventricular VAD (129 ± 90 m vs 85 ± 67 m, P = .043) as well as destination therapy and bridge-to-transplant (184 ± 88 m vs 102 ± 82 m, P = .005). CONCLUSIONS: Patients with VAD implantation had statistically and clinically significant improvements in EC and QoL as assessed with the MNH during CR. Patients on destination therapy showed a larger benefit from CR than bridge-to-transplant patients and patients with left VAD improved more than biventricular VAD patients.

Transfer of Clinical Drug Data to a Research Infrastructure on OMOP - A FAIR Concept.

Generating evidence based on real-world data is gaining importance in research not least since the COVID-19 pandemic. The Common Data Model of Observational Medical Outcomes Partnership (OMOP) is a research infrastructure that implements FAIR principles. Although the transfer of German claim data to OMOP is already implemented, drug data is an open issue. This paper provides a concept to prepare electronic health record (EHR) drug data for the transfer to OMOP based on requirements analysis and descriptive statistics for profiling EHR data developed by an interdisciplinary team and also covers data quality issues. The concept not only ensures FAIR principles for research, but provides the foundation for German drug data to OMOP transfer.

Treatment of Advanced Heart Failure-Focus on Transplantation and Durable Mechanical Circulatory Support: What Does the Future Hold?

Heart transplantation (HTx) is the treatment of choice in patients with late-stage advanced heart failure (Advanced HF). Survival rates 1, 5, and 10 years after transplantation are 87%, 77%, and 57%, respectively, and the average life expectancy is 9.16 years. However, because of the donor organ shortage, waiting times often exceed life expectancy, resulting in a waiting list mortality of around 20%. This review aims to provide an overview of current standard, recent advances, and future developments in the treatment of Advanced HF with a focus on long-term mechanical circulatory support and HTx.

Sternectomy for Candida albicans sternal osteomyelitis after left ventricular assist device implantation.

Fungal osteomyelitis is an uncommon complication after cardiac surgery and associated with high mortality. A case of Candida albicans and Staphylococcus epidermidis osteomyelitis with device infection after implantation of a left ventricular assist device in a 60-year-old male patient is presented here. After clinical identification and confirmation with microbiological examinations and fluorodeoxyglucose positron emission tomography (FDG-PET) scan, debridement was performed. Surgical specimens grew C. albicans and S. epidermidis. Fluconazole, daptomycin, and negative pressure wound therapy were initiated, but failed to achieve healing. Total sternectomy and pectoralis flap reconstruction were performed. There was no recurrent infection for C. albicans on a prolonged antifungal regime. The combination of antifungal therapy and aggressive surgical debridement may be useful to control fungal osteomyelitis.

Possible Prosthetic Valve Endocarditis by Pandoraea pnomenusa and Specific Virulence Mechanisms.

Bacteremia by Pandoraea spp. has rarely been described before. We report the first case of a P. pnomenusa possible prosthetic valve endocarditis, according to the modified Duke criteria, in a 37-year old male injecting drug user suffering from recurrent endocarditis. Furthermore, we demonstrate biofilm formation by the P. pnomenusa isolates of this patient and investigate antibiotic resistance.

Design optimization of bidirectional arterial perfusion cannula.

OBJECTIVES: Determine if shortening the covered section of a self-expanding bidirectional arterial cannula, can enhance retrograde flow and thus reduce the risk of lower limb ischemia. METHODS: Outlet pressure vs flow rate was determined for three cannulas types: a 15F self-expanding bidirectional cannula having a covered section of 90 mm, the same cannula but with a shorter covered section of 60 mm, and a Biomedicus cannula as control. The performances of all the cannulas were compared using a computerized flow-bench with calibrated sensors and a centrifugal pump. Water retrograde flow was determined using a tank timer technique. Anterograde and retrograde flow rate versus outlet pressure were determined at six different pump speed. RESULTS: For each of the six pump speed, both bidirectional cannulas, 60-mm covered and 90-mm covered respectively, showed higher performance than Biomedicus cannula control, as demonstrated by higher flow rate and lower pressure. We also observed that for the bidirectional cannula with shorter covered section, i.e. 60 mm coverage, provides enhanced performance as compared to a 90-mm coverage. Finally, the flow rate and the corresponding pressure can be consistently measured by our experimental set-up with low variability. CONCLUSIONS: The new configuration of a shorter covered section in a bidirectional self-expanding cannula design, may present an opportunity to overcome lower leg ischemia during extra-corporal life support with long term peripheral cannulation.

An innovative cold storage system for donor heart transportation-lessons learned from the first experience in Switzerland.

BACKGROUND: The current standard for donor heart preservation consists of cold organ storage in three sequential plastic bags. This technique can cause freezing injuries of the donor heart as the temperature inside the transport box is not monitored routinely. The SherpaPak™ Cardiac Transport System (CTS) (Paragonix Technologies, Cambridge, MA, USA) aims to resolve this problem by maintaining a controlled preservation temperature between 4 and 8 °C. This study reports the first single-centre experience in Switzerland with this innovative single-use disposable device. METHODS: Between May and December 2020, four heart procurements using SherpaPak™ CTS were performed at our heart centre. Donor heart preservation fluid and ambient temperature were monitored using the InTempConnect® application (Onset Computer Corporation, Bourne, MA, USA). All patient data were collected retrospectively from the local hospital patient data capture system. RESULTS: Four recipients of a donor heart preserved with SherpaPak™ CTS were included in this study (3 male, 1 female). Mean transport distance was 86 km (range, 45-276 km). Mean storage time in the cooler was 73.5±19.33 minutes. Mean cold ischemic time was 199.25±11.67 minutes. The device kept the average organ temperature between 5.2 and 8.8 °C and hereby reached the recommended temperature range of 5-10 °C. Modifications of the procurement and storage process provided an optimization of the temperature course in the transportation box. There were no incidents during the transport. Organs transported with this novel storage system showed normal function after transplantation. CONCLUSIONS: The SherpaPak™ CTS provides constant organ temperatures during transportation, prevents freezing injury and ensures mechanical protection of the graft. KEYWORDS: Heart transplantation; organ procurement; cold storage; hypothermic injury; graft transport.