Intraoperative and Intraprocedural Use of 3-Dimensional Transesophageal Echocardiography: An International European Association of Cardiothoracic Anesthesia and Intensive Care Survey of Cardiac Surgical Centers.

OBJECTIVE: To assess the intraoperative use of 3-dimensional transesophageal echocardiography (3D TEE) in cardiac surgical centers, the authors created a survey aimed at evaluating the availability of equipment and the use of 3D TEE for specific surgical and interventional procedures and single-image modalities. The respondents were asked to identify the perceived impact on patient management and current limitations to its routine use. DESIGN: A multiple choice 25-question online survey submitted to the members of the European Association of Cardiothoracic Anesthesia and Intensive Care (EACTAIC) on December 6, 2021, and closed on January 31, 2022. SETTING: An online survey. PARTICIPANTS: Registered EACTAIC members in 2021. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 239 respondents from 44 different countries took part in the survey (27% of the total 903 EACTAIC members). Most respondents (59%) were TEE-certified by the National Board of Echocardiography, European Association of Cardiovascular Imaging (EACVI/EACTAIC), or had a national certificate. Of the respondents, 68% had no formal 3D TEE training. Eight percent of respondents had no 3D machines, whereas 40% had one for each operating room, and 33% had only one for the entire operating room block. 3D TEE was performed most frequently in more than 67% of cases for mitral valve surgery, and in more than 54% of cases for mitral and tricuspid clips, aortic valve, tricuspid valve, and aortic surgery. CONCLUSION: Current guidelines suggest integrating 3D TEE into all comprehensive examinations. The authors' survey reported that intraoperative 3D TEE was used in the majority of mitral valve surgery and only one-half of the other valve surgeries and transcatheter procedures. Its use may be explained by the availability of 3D machines, trained personnel, and limited time to perform TEE in the operating room. Educational initiatives for training in 3D TEE may further increase its routine use.

Interventions Triggered During Routine Use of NIRS Cerebral Oxygenation Monitoring in Cardiac Surgical Patients.

OBJECTIVE: The purpose of this study was to determine the incidence and types of interventions triggered during a drop of baseline near-infraredspectroscopy (NIRS) values in consecutive cardiac surgical patients. DESIGN: A single-center, retrospective observational study. SETTING: A university-affiliated tertiary care center. PARTICIPANTS: Three thousand three hundred two consecutive cardiac surgical patients from October 2016 to August 2017 Interventions: None. MEASUREMENTS AND MAIN RESULTS: Of the 1,972 patients who met the inclusion criteria, 576 (29.2%) patients showed NIRS deviation of -20% from baseline. Interventions performed during the drop of baseline NIRS values were documented in 285 (14.4%) patients, with a total of 391 interventions. Three hundred fifteen (80%) interventions were triggered by a deviation in NIRS and concomitant changes in standard monitoring parameters. Seventy-six (20%) interventions were triggered by NIRS deviation alone, with no concomitant pathologic deviation in standard monitoring. A total of 279 (71%) interventions were performed on patients who had no recommendation for NIRS monitoring by current national guidelines. Out of these, 30 (7.7%) interventions (1.3% of all patients) were performed based on NIRS monitoring alone. The higher risk deviation group had longer intensive care unit and hospital lengths of stays (one and 15 days) and postoperative delirium when compared with the no-deviation group (zero and 13 days) Conclusions: The authors' data suggested that most interventions triggered during the drop of baseline values during routine use of NIRS would have also been triggered by the concomitant changes in standard monitoring parameters. Routine use of NIRS for all cardiac surgical patients still is debatable and needs to be evaluated in a large prospective trial.

Canadian recommendations for training and performance in basic perioperative point-of-care ultrasound: recommendations from a consensus of Canadian anesthesiology academic centres.

Point-of-care ultrasound (POCUS) uses ultrasound at the bedside to aid decision-making in acute clinical scenarios. The increased use of ultrasound for regional anesthesia and vascular cannulation, together with more anesthesiologists trained in transesophageal echocardiography have contributed to the widespread use of POCUS in perioperative care. Despite the support of international experts, the practice of POCUS in perioperative care is variable as Canadian guidelines for anesthesiologists do not currently exist. Using a Delphi process of online surveys and a face-to-face national Canadian meeting, we developed a consensus statement for basic POCUS (bPOCUS) performance and training with a group of national experts from all Canadian universities. The group of experts consisted of 55 anesthesiologists from 12 Canadian universities considered local leaders in the field. An initial exploratory online survey of 47 statements was conducted. These statements were derived from previous generic guidelines or consensus conferences, or were based on current literature. Fourteen statements reached full consensus, 19 had 90-100% agreement, and 14 had less than 90% agreement. Eight new statements were proposed during the national meeting, and all statements without full agreement were discussed. A second online survey included 42 modified or new statements. From this second survey, 16 statements obtained full consensus, 39 had very good agreement, and one had good agreement. The final document includes 56 statements that define the scope of practice and necessary training for perioperative bPOCUS. The statements include five bPOCUS domains: cardiac, lung, airway, gastric, and abdomen. The use of bPOCUS is evolving and will play a significant role in perioperative medicine. This consensus statement aims to define a Canadian national standard on which curricula may be based. It also provides a framework to allow further development of bPOCUS in the perioperative setting.

RéSUMé: L'échographie ciblée (POCUS) utilise l'échographie au chevet des patients pour faciliter la prise de décisions dans les situations cliniques urgentes. L'utilisation accrue de l'échographie pour l'anesthésie régionale et la cannulation vasculaire, ainsi que l'augmentation du nombre d'anesthésologistes formés à l'échocardiographie transesophagienne, ont contribué à l'utilisation généralisée de l'échographie ciblée dans les soins périopératoires. Malgré son endossement par des experts internationaux, la pratique de l'échographie ciblée en soins périopératoires est variable, car il n'existe pas, à l'heure actuelle, de lignes directrices canadiennes destinées aux anesthésiologistes. À l'aide d'un processus Delphi de sondages en ligne et d'une réunion nationale canadienne en personne, un groupe d'experts nationaux provenant de toutes les universités canadiennes a élaboré une déclaration consensuelle pour la formation de base en et l'exécution de l'échographie ciblée (bPOCUS). Le groupe d'experts était composé de 55 anesthésiologistes issus de 12 universités canadiennes considérés comme des chefs de file locaux dans le domaine. Un premier sondage exploratoire en ligne comportant 47 énoncés a été réalisé. Ces énoncés étaient dérivés de lignes directrices antérieures ou de conférences consensuelles, ou étaient fondés sur la littérature actuelle. Quatorze énoncés ont obtenu un consensus complet, 19 ont atteint un taux de 90 à 100 %, et 14 ont obtenu moins de 90 % d'accord. Huit nouveaux énoncés ont été proposés au cours de la réunion nationale, et tous les énoncés n'ayant pas obtenu d'accord complet ont été discutés. Un deuxième sondage en ligne comprenait 42 énoncés modifiés ou nouveaux. Dans ce deuxième sondage, 16 énoncés ont obtenu un consensus total, 39 un très bon accord et un énoncé un bon accord. Le document final comporte 56 énoncés qui définissent le champ de pratique et la formation nécessaire pour l'échographie ciblée périopératoire de base. Les énoncés portent sur cinq domaines de l'échographie ciblée de base : échographie cardiaque, pulmonaire, des voies respiratoires, gastrique et abdominale. L'utilisation de l'échographie ciblée de base évolue et jouera un rôle important en médecine périopératoire. Cette déclaration consensuelle vise à définir une norme nationale canadienne sur laquelle les programmes d'études pourront s'appuyer. Elle fournit également un cadre pour encourager le développement ultérieur de l'échographie ciblée de base dans un contexte périopératoire.

Evaluation of a Patient-Specific, Low-Cost, 3-Dimensional-Printed Transesophageal Echocardiography Human Heart Phantom.

OBJECTIVE: Currently available 3-dimensional (3D) modeling and printing techniques allow for the creation of patient-specific models based on 3D medical imaging data. The authors hypothesized that a low-cost, patient-specific, cardiac computed tomography-based phantom, created using desktop 3D printing and casting, would have comparable image quality, accuracy, and usability to an existing commercially available echocardiographic phantom. DESIGN: Blinded comparative study. SETTING: Simulation laboratory at a single academic institution. PARTICIPANTS: Voluntary cardiac anesthesiologists at a single academic institution. INTERVENTIONS: Stage 1 of the study consisted of an online questionnaire in which a set of basic transesophageal echocardiography (TEE) views obtained from the 3D printed phantom and commercial phantom were presented to participants, who had to identify the views and evaluate their fidelity to clinical images on a Likert scale. In stage 2, participants performed an unblinded basic TEE examination on both phantoms. MEASUREMENTS AND MAIN RESULTS: The time needed to acquire each basic view was recorded. Overall usability of the phantoms was assessed through a questionnaire. The participants could recognize most of the views. Fidelity ratings for both phantoms were similar (p < 0.05), with the exception of a midesophageal 2-chamber view that was observed better on the 3D printed phantom. The time required to obtain the views was shorter for the 3D printed phantom, although not statistically significant for most views. The overall user experience was better for the 3D phantom for all categories examined (p < 0.05). CONCLUSIONS: The study suggested that a 3D-printed TEE phantom is comparable with the commercially available one with good usability.

Anaesthesia for minimally invasive cardiac procedures in the catheterization lab.

PURPOSE OF REVIEW: The share of cardiac procedures performed in settings involving nonoperating room anaesthesia (NORA) continues to grow rapidly, and the number of publications related to anaesthetic techniques in cardiac catheterization laboratories is substantial. We aim to summarize the most recent evidence about outcomes related to type of anaesthetic in minimally invasive cardiac procedures. RECENT FINDINGS: The latest studies, primarily focused on transcatheter aortic valve replacement (TAVR) and transcatheter mitral valve repair (TMVr), demonstrate the need for reliable monitoring and appropriate training of the interdisciplinary teams involved in this high-risk NORA setting. SUMMARY: Inappropriate sedation and concurrent inadequate oxygenation are main risk factors for claims involving NORA care. Current evidence deriving from TAVR shows that monitored anaesthesia care (MAC) is associated with shorter length of stay and lower mortality.

Multi-organ point-of-care ultrasound for COVID-19 (PoCUS4COVID): international expert consensus.

COVID-19 has caused great devastation in the past year. Multi-organ point-of-care ultrasound (PoCUS) including lung ultrasound (LUS) and focused cardiac ultrasound (FoCUS) as a clinical adjunct has played a significant role in triaging, diagnosis and medical management of COVID-19 patients. The expert panel from 27 countries and 6 continents with considerable experience of direct application of PoCUS on COVID-19 patients presents evidence-based consensus using GRADE methodology for the quality of evidence and an expedited, modified-Delphi process for the strength of expert consensus. The use of ultrasound is suggested in many clinical situations related to respiratory, cardiovascular and thromboembolic aspects of COVID-19, comparing well with other imaging modalities. The limitations due to insufficient data are highlighted as opportunities for future research.

Immediate Impact of Prosthetic Graft Replacement of the Ascending Aorta on Circumferential Strain in the Descending Aorta.

OBJECTIVES: Prosthetic replacement of the ascending aorta (AA) can potentially modify energy propagation to the distal aorta and contribute to adverse aortic remodelling. This preliminary study employed intra-operative transoesophageal echocardiography (TOE) to assess the immediate impact of prosthetic graft replacement of the AA on circumferential strain in the descending aorta. METHODS: Intra-operative TOEs in patients undergoing AA graft replacement were analysed for circumferential strain, fractional area change (FAC), dimensions (end diastolic area [EDA], and end systolic area [ESA]) in the descending aorta immediately before and after graft replacement. Deformation was assessed via global peak circumferential aortic strain (CAS), together with pulse pressure corrected strain, time to peak strain (TTP), and aortic distensibility. RESULTS: Forty-five patients undergoing AA replacement with prosthetic graft (91% elective) were studied. Following grafting, descending thoracic aortic circumferential strain increased (6.3 ± 2.8% vs. 8.9 ± 3.4%, p = .001) paralleling distensibility (5.7 [3.7-8.6] 10-3 mmHg vs. 8.5 [6.4-12.4] 10-3 mmHg, p < .001). Despite slight increments in post graft left ventricular ejection fraction (LVEF) (52.3 ± 10.8% vs. 55.0 ± 11.9, p < .001), stroke volume was similar (p = .41), and magnitude of increased strain did not correlate with change in stroke volume (r = -.03, p = .86), LVEF (r = .18, p = .28), or pulse pressure (r = .28, p = .06). Descending aortic size (EDA 4 [2.7-4.6] cm2vs. 3.7 [2.5-5] cm2, p = .89; ESA 4.3 [3.2-5.3] cm2vs. 4.5 [3.3-5.8] cm2, p = .14) was similar pre- and post graft. In subgroup analysis, patients with cystic medial necrosis had a significantly higher post procedure CAS than patients with atherosclerotic aneurysms (9.7 ± 3.5% vs. 7.0 ± 2.3%, p = .03). CONCLUSIONS: Prosthetic graft replacement of the AA increases immediate aortic circumferential strain of the descending aorta, particularly in patients with cystic medial necrosis. Our findings suggest that grafts augment energy transfer to the distal aorta, a potential mechanism for progressive distal aortic dilation and/or dissection.

New Strategies to Expand and Optimize Heart Donor Pool: Ex Vivo Heart Perfusion and Donation After Circulatory Death: A Review of Current Research and Future Trends.

Heart transplantation remains the definitive management for end-stage heart failure refractory to medical therapy. While heart transplantation cases are increasing annually worldwide, there remains a deficiency in organ availability with significant patient mortality while on the waiting list. Attempts have therefore been made to expand the donor pool and improve access to available organs by recruiting donors who may not satisfy the standard criteria for organ donation because of donor pathology, anticipated organ ischemic time, or donation after circulatory death. "Ex vivo" heart perfusion (EVHP) is an emerging technique for the procurement of heart allografts. This technique provides mechanically supported warm circulation to a beating heart once removed from the donor and before implantation into the recipient. EVHP can be sustained for several hours, facilitate extended travel time, and enable administration of pharmacological agents to optimize cardiac recovery and function, as well as allow assessment of allograft function before implantation. In this article, we review recent advances in expanding the donor pool for cardiac transplantation. Current limitations of conventional donor criteria are outlined, including the determinants of organ suitability and assessment, involving transplantation of donation after circulatory death hearts, extended criteria donors, and EVHP-associated assessment, optimization, and transportation. Finally, ongoing research relating to organ optimization and functional ex vivo allograft assessment are reviewed.

Aortic root changes before and after surgery for chronic aortic dilatation: A 3D echocardiographic study.

BACKGROUND: Quantitative 3D assessment of the aortic root may improve planning and success of aortic valve (AV)-sparing operations. AIMS: To use 3D transesophageal echocardiography (TEE) to assess the effect of chronic aortic dilatation on aortic root shape and aortic regurgitation (AR) severity and to examine the effects of AV-sparing operations. METHODS AND RESULTS: To determine the changes with chronic aortic dilatation, we studied 48 patients, 23 with aortic dilatation (Group 1 ≤ mild AR, n = 13; Group 2 ≥ moderate AR, n = 10) and 25 Controls. To determine the changes in AV-sparing operations, a subgroup of 15 patients were examined pre- and post surgery. 3D-TEE images were analyzed using multiplanar reconstruction (QLAB, Philips, Philips Medical Systems, Andover, MA, USA) to obtain aortic root areas, diameters, and lengths. We also calculated a novel parameter called total coaptation surface area (TCoapSA), which sums the contact surface area of all the AV cusps. Compared to Controls, Groups 1 and 2 had significantly larger aortic root areas, inter-commissural distances, and cusp heights. Compared to Group 1 and Controls, Group 2 had significantly smaller TCoapSA when adjusted for aortic annular area (P = 0.001) with shorter coaptation height (P < 0.001). In patients undergoing AV-sparing surgery, TCoapSA was significantly larger post surgery (P = 0.001) with greater coaptation height (P < 0.001) and smaller inter-commissural distances (P < 0.001). CONCLUSIONS: The aortic valve is a dynamic structure that remodels in response to aortic dilatation. Successful valve-sparing surgery corrects these changes. Quantitative modeling of the aortic valve and root could potentially improve the repair to the individual patients and modify outcomes.

Validation of Quantitative 3-Dimensional Transesophageal Echocardiography Mitral Valve Analysis Using Stereoscopic Display.

OBJECTIVE: The use of 3-dimensional (3D) transesophageal echocardiography (TEE) in perioperative evaluation of the mitral valve (MV) is increasing progressively, including the use of 3D MV models for quantitative analysis. However, the use of 3D MV models in clinical practice still is limited by the need for specific training and the long time required for analysis. A new stereoscopic visualization tool (EchoPixel True 3D) allows virtual examination of anatomic structures in the clinical setting, but its accuracy and feasibility for intraoperative use is unknown. The aim of this study was to assess the feasibility of 3D holographic display and evaluate 3D quantitative measurements on a volumetric MV image using the EchoPixel system compared with the 3D MV model generated by QLAB Mitral Valve Navigation (MVN) software. DESIGN: This was a retrospective comparative study. SETTING: The study took place in a tertiary care center. PARTICIPANTS: A total of 40 patients, 20 with severe mitral regurgitation who underwent mitral valve repair and 20 controls with normal MV, were enrolled retrospectively. INTERVENTIONS: The 3D-TEE datasets of the MV were analyzed using a 3D MV model and stereoscopic display. The agreement of measurements, intraobserver and interobserver variability, and time for analysis were assessed. MEASUREMENTS AND MAIN RESULTS: Fair agreement between the 2 software systems was found for annular circumference and area in pathologic valves, but good agreement was reported for prolapse height and linear annular diameters. A higher agreement for all annular parameters and prolapse height was seen in normal valves. Excellent intraobserver and interobserver reliability was proved for the same parameters; time for analysis between the 2 methods in pathologic valves was substantially equivalent, although longer in pathologic valves when compared with normal MV using both tools. CONCLUSION: EchoPixel proved to be reliable to display 3D TEE datasets and accurate for direct linear measurement of both MV annular sizes and prolapse height compared to QLAB MVN software; it also carries a low interobserver and intraobserver variability for most measurements.

Anesthesia for Percutaneous Pulmonary Valve Implantation: A Case Series.

BACKGROUND: Twenty percent of patients born with congenital heart disease present with right ventricular outflow tract abnormalities. These patients require multiple surgical procedures in their lifetime. Transcatheter pulmonary valve replacement (TPVR) has become a viable alternative to conventional pulmonary valve and right ventricular outflow tract surgery in pediatric and adult populations. In this retrospective review, we analyze the perioperative management of adult patients who underwent TPVR in our center. METHODS: The study consisted of a chart review of patients who underwent TPVR at Toronto General Hospital between 2006 and 2015. Information about preoperative assessment, intraoperative anesthetic management, and intra- and postprocedural complications was collected. Two types of percutaneous valves have been used for a conduit or valve size between 16 and 28 mm. These procedures are done via the femoral, jugular, or subclavian vein under general anesthesia. RESULTS: Seventy-nine adults (17-68 years of age) who underwent elective TPVR procedures were included. General anesthesia was used in all cases. Defibrillation was necessary in 1 case, and bradycardia was spontaneously resolved in another 1. Eighty-five percent were successfully extubated at the end of the procedure. Five patients required intraoperative inotropic support. Three patients presented self-resolved hemoptysis. Mechanical ventilation for >24 hours was necessary in 3 cases, 2 of which also required concomitant inotropic support. Four failed deployments and 1 case of persistent conduit stenosis were reported. Three patients required reintubation. All patients were discharged home. CONCLUSIONS: Patients undergoing TPVR represent a complex and heterogeneous population. General anesthesia with endotracheal intubation is preferred. Setup for urgent lung isolation and cardiac defibrillation should be considered. Postoperative monitoring and intensive care setting are required. Anesthesiologists with cardiac anesthesia training are probably better suited to manage these patients.

Description of a Novel Set-up for Functional Echocardiographic Assessment of Left Ventricular Performance During Ex Vivo Heart Perfusion.

Ex vivo heart perfusion (EVHP) is a new technology aimed at decreasing cold ischemia time and evaluating cardiac function before transplanting a donor heart. In an experimental EVHP swine model, we tested a 3D-printed custom-made set-up to perform surface echocardiography on an isolated beating heart during left ventricular loading. The views obtained at any time point were equivalent to standard transesophageal and transthoracic views. A decrease in left ventricular function during EVHP was observed in all experiments.

Core point-of-care ultrasound curriculum: What does every anesthesiologist need to know?

Point-of-care ultrasound (POCUS) is becoming an integral part of anesthesia practice throughout the world. Despite the growing interest in POCUS among trainees and faculty, POCUS training is variable among universities across Canada. This suggests a need for curriculum development and standardization. International guidelines for Emergency Medicine and Critical Care have common frameworks and may be used as a reference to model anesthesia-specific curricula. The Royal College of Anaesthetists of the United Kingdom currently offers the only nationally approved POCUS curriculum for anesthesia and critical care trainees. Most curricula have in common a stepwise approach that consists of foundation of knowledge and skills and competency building through practice. Nevertheless, a significant variety of didactic modalities have been described, and online learning and simulation offer clear advantages. What constitutes the minimum number of studies necessary to achieve competence is still debated as are the most appropriate tools for assessment of POCUS competency.Availability of trained staff anesthesiologists remains a major limitation to curricula implementation in most centres. A National Curriculum should be modeled on the Competency By Design Approach, in line with the CanMEDS 2015 roles, and start with a focus on basic POCUS modalities and applications. Guidance for the training and certification of POCUS among practicing anesthesiologists is lacking.

Internal jugular vein blood flow in the upright position during external compression and increased central venous pressure: an ultrasound study in healthy volunteers.

BACKGROUND: External compression of the jugular veins is an effective method to increase intracranial blood volume and brain stiffness in rats and healthy volunteers. It has been reported that, on assuming an upright posture, cerebral venous drainage is distributed away from the internal jugular veins (IJVs) to the cervical venous plexus, causing complete collapse of the IJV. If so, it is not clear why external IJV compression would increase intracranial blood volume, but the latter is frequently observed in neurosurgery in the sitting position. The aim of this study was to observe the effect of external IJV compression and the Valsalva maneuver on the change in IJV cross-sectional area and IJV flow in volunteers in the upright posture. METHODS: After Research Ethics Board approval, we used ultrasound to evaluate both IJV cross-sectional areas and peak velocities in ten healthy volunteers in the sitting position. With the volunteers breathing normally at rest, we applied the Valsalva maneuver along with circumferential supraclavicular compression of 15 mmHg. Imaging was performed at the level of the cricoid cartilage and at the most superior level under the mandible. The IJV flow was calculated using the product of Doppler velocity and IJV cross-sectional area. RESULTS: Flow was detected in both IJVs of all subjects. The median [interquartile range] cross-sectional area for the right IJV at the level of the cricoid was 0.04 [0.03-0.08] cm2 (baseline), with collar 0.4 [0.2-0.6] cm2 (P = 0.003 compared with baseline). There were no significant changes in the median blood flow. CONCLUSIONS: Compression of the internal jugular veins or an increase in intrathoracic pressure does not reduce venous drainage but actually may increase intracranial venous volume.

Double trouble: A case of periprocedural detection of intracardiac thrombus and aortic root dissection during emergent transfemoral TAVR.

We report a case of emergency transcatheter aortic valve replacement (TAVR) in a 65-year-old patient presenting with decompensated severe aortic stenosis. Transesophageal echocardiography (TEE) was used effectively to obtain measurements of the aortic annulus and for intra-procedural guidance. At baseline, we detected a left atrial appendage thrombus and a localized aortic root dissection after balloon valvuloplasty. The case highlights the important role that TEE may play during TAVR procedures.

Correlation Between Transhepatic and Subcostal Inferior Vena Cava Views to Assess Inferior Vena Cava Variation: A Pilot Study.

OBJECTIVES: To assess the feasibility and reliability of transthoracic echocardiography to measure inferior vena cava (IVC) diameter variation using a transhepatic view. DESIGN: Prospective cohort study. SETTING: Single-center hospital. PATIENTS: Forty consecutive patients undergoing elective cardiac surgery. INTERVENTIONS: Bedside transthoracic echocardiography. MEASUREMENTS AND MAIN RESULTS: Correlation between the two views was measured using Pearson R, while agreement was measured using the intraclass correlation coefficient (ICC). In a nested sub-study of 16 randomly selected participants, all images were re-rated by the same rater, who was blinded to the original measurement results, and by a second blinded operator. Correlation between the subcostal and transhepatic views was moderate when assessing maximum (R 0.46; 95% confidence interval [CI], 0.18-0.68), and minimum (R 0.55; CI, 0.29-0.74) IVC diameter. Correlation when measuring IVC diameter variation was higher (R 0.70; CI, 0.49-0.83). Agreement between the two views for IVC diameter variation measurement was substantial (ICC 0.73; CI, 0.49-0.85). Intra-rater reliability was excellent (ICC 0.95-0.99). CONCLUSIONS: Agreement between subcostal and transhepatic views was substantial for the assessment of IVC diameter variation; however, the magnitude of agreement was less than anticipated. Further research is needed to determine if the transhepatic view can be used reliably in the assessment of fluid responsiveness.

A New Multi-Mode Perfusion System for Ex Vivo Heart Perfusion Study.

Ex vivo heart perfusion has been shown to be an effective means of facilitating the resuscitation and assessment of donor hearts for cardiac transplantation. Over the last ten years however, only a few ex vivo perfusion systems have been developed for this application. While results have been promising, a system capable of facilitating multiple perfusion strategies on the same platform has not yet been realized. In this paper, the design, development and testing of a novel and modular ex vivo perfusion system is described. The system is capable of operating in three unique primary modes: the traditional Langendorff Mode, Pump-Supported Working-Mode, and Passive Afterload Working-Mode. In each mode, physiological hemodynamic parameters can be produced by managing perfusion settings. To evaluate heart viability, six experiments were conducted using porcine hearts and measuring several parameters including: pH, aortic pressure, lactate metabolism, coronary vascular resistance (CVR), and myocardial oxygen consumption. Pressure-volume relationship measurements were used to assess left ventricular contractility in each Working Mode. Hemodynamic and metabolic conditions remained stable and consistent across 4 h of ex vivo heart perfusion on the ex vivo perfusion system, validating the system as a viable platform for future development of novel preservation and assessment strategies.

Mortality in patients with normal left ventricular function requiring emergency VA-ECMO for postcardiotomy cardiogenic shock due to coronary malperfusion.

OBJECTIVES: To analyze outcomes in patients with normal preoperative left ventricular ejection fraction (LVEF) undergoing venoarterial extracorporeal membrane oxygenation (VA-ECMO) therapy due to postcardiotomy cardiogenic shock (PCCS) related to coronary malperfusion. METHODS: Retrospective single-center analysis in patients with normal preoperative LVEF treated with VA-ECMO for coronary malperfusion-related PCCS between May 1998 and May 2018. The primary outcome was 30-day mortality, which was compared using the Kaplan-Meier method and the log-rank test. Multivariable logistic regression was performed to identify predictors of mortality. RESULTS: During the study period, a total of 62,125 patients underwent cardiac surgery at our institution. Amongst them, 59 patients (0.1%) with normal preoperative LVEF required VA-ECMO support due to coronary malperfusion-related PCCS. The mean duration of VA-ECMO support was 6 days (interquartile range 4-7 days). The 30-day mortality was 50.8%. Under VA-ECMO therapy, a complication composite outcome of bleeding, re-exploration for bleeding, acute renal failure, acute liver failure, and sepsis occurred in 51 (86.4%) patients. Independent predictors of 30-day mortality were lactate levels > 9.9 mmol/l before VA-ECMO implantation (odds ratio [OR]: 3.3; 95% confidence interval [CI] 1.5-7.0; p = 0.002), delay until revascularization > 278 minutes (OR: 2.9; 95% CI 1.3-6.4; p = 0.008) and peripheral arterial artery disease (OR: 3.3; 95% 1.6-7.5; p = 0.001). CONCLUSIONS: Mortality rates are high in patients with normal preoperative LVEF who develop PCCS due to coronary malperfusion. The early implantation of VA-ECMO before the development of profound tissue hypoxia and early coronary revascularization increases the likelihood of survival. Lactate levels are useful to define optimal timing for the VA-ECMO initiation.