Perioperative diagnosis and impact of acquired von Willebrand syndrome in infants with congenital heart disease.

Acquired von Willebrand syndrome (aVWS) has been reported in patients with congenital heart diseases associated with shear stress caused by significant blood flow gradients. Its etiology and impact on intraoperative bleeding during pediatric cardiac surgery have not been systematically studied. This single-center, prospective, observational study investigated appropriate diagnostic tools of aVWS compared with multimer analysis as diagnostic criterion standard and aimed to clarify the role of aVWS in intraoperative hemorrhage. A total of 65 newborns and infants aged 0 to 12 months scheduled for cardiac surgery at our tertiary referral center from March 2018 to July 2019 were included in the analysis. The glycoprotein Ib M assay (GPIbM)/von Willebrand factor antigen (VWF:Ag) ratio provided the best predictability of aVWS (area under the receiver operating characteristic curve [AUC], 0.81 [95% CI, 0.75-0.86]), followed by VWF collagen binding assay/VWF:Ag ratio (AUC, 0.70 [0.63-0.77]) and peak systolic echocardiographic gradients (AUC, 0.69 [0.62-0.76]). A cutoff value of 0.83 was proposed for the GPIbM/VWF:Ag ratio. Intraoperative high-molecular-weight multimer ratios were inversely correlated with cardiopulmonary bypass (CPB) time (r = -0.57) and aortic cross-clamp time (r = -0.54). Patients with intraoperative aVWS received significantly more fresh frozen plasma (P = .016) and fibrinogen concentrate (P = .011) than those without. The amounts of other administered blood components and chest closure times did not differ significantly. CPB appears to trigger aVWS in pediatric cardiac surgery. The GPIbM/VWF:Ag ratio is a reliable test that can be included in routine intraoperative laboratory workup. Our data provide the basis for further studies in larger patient cohorts to achieve definitive clarification of the effects of aVWS and its potential treatment on intraoperative bleeding.

Inhaled prostacyclin therapy in the acute respiratory distress syndrome: a randomized controlled multicenter trial.

BACKGROUND: Acute respiratory distress syndrome (ARDS) results in significant hypoxia, and ARDS is the central pathology of COVID-19. Inhaled prostacyclin has been proposed as a therapy for ARDS, but data regarding its role in this syndrome are unavailable. Therefore, we investigated whether inhaled prostacyclin would affect the oxygenation and survival of patients suffering from ARDS. METHODS: We performed a prospective randomized controlled single-blind multicenter trial across Germany. The trial was conducted from March 2019 with final follow-up on 12th of August 2021. Patients with moderate to severe ARDS were included and randomized to receive either inhaled prostacyclin (3 times/day for 5 days) or sodium chloride (Placebo). The primary outcome was the oxygenation index in the intervention and control groups on Day 5 of therapy. Secondary outcomes were mortality, secondary organ failure, disease severity and adverse events. RESULTS: Of 707 patients approached 150 patients were randomized to receive inhaled prostacyclin (n = 73) or sodium chloride (n = 77). Data from 144 patients were analyzed. The baseline PaO2/FiO2 ratio did not differ between groups. The primary analysis of the study was negative, and prostacyclin improved oxygenation by 20 mmHg more than Placebo (p = 0.17). Secondary analysis showed that the oxygenation was significantly improved in patients with ARDS who were COVID-19-positive (34 mmHg, p = 0.04). Mortality did not differ between groups. Secondary organ failure and adverse events were similar in the intervention and control groups. CONCLUSIONS: The primary result of our study was negative. Our data suggest that inhaled prostacyclin might be beneficial treatment in patients with COVID-19 induced ARDS. TRIAL REGISTRATION: The study was approved by the Institutional Review Board of the Research Ethics Committee of the University of Tübingen (899/2018AMG1) and the corresponding ethical review boards of all participating centers. The trial was also approved by the Federal Institute for Drugs and Medical Devices (BfArM, EudraCT No. 2016003168-37) and registered at clinicaltrials.gov (NCT03111212) on April 6th 2017.

Intravenous IgM-enriched immunoglobulins in critical COVID-19: a multicentre propensity-weighted cohort study.

BACKGROUND: A profound inflammation-mediated lung injury with long-term acute respiratory distress and high mortality is one of the major complications of critical COVID-19. Immunoglobulin M (IgM)-enriched immunoglobulins seem especially capable of mitigating the inflicted inflammatory harm. However, the efficacy of intravenous IgM-enriched preparations in critically ill patients with COVID-19 is largely unclear. METHODS: In this retrospective multicentric cohort study, 316 patients with laboratory-confirmed critical COVID-19 were treated in ten German and Austrian ICUs between May 2020 and April 2021. The primary outcome was 30-day mortality. Analysis was performed by Cox regression models. Covariate adjustment was performed by propensity score weighting using machine learning-based SuperLearner to overcome the selection bias due to missing randomization. In addition, a subgroup analysis focusing on different treatment regimens and patient characteristics was performed. RESULTS: Of the 316 ICU patients, 146 received IgM-enriched immunoglobulins and 170 cases did not, which served as controls. There was no survival difference between the two groups in terms of mortality at 30 days in the overall cohort (HRadj: 0.83; 95% CI: 0.55 to 1.25; p = 0.374). An improved 30-day survival in patients without mechanical ventilation at the time of the immunoglobulin treatment did not reach statistical significance (HRadj: 0.23; 95% CI: 0.05 to 1.08; p = 0.063). Also, no statistically significant difference was observed in the subgroup when a daily dose of ≥ 15 g and a duration of ≥ 3 days of IgM-enriched immunoglobulins were applied (HRadj: 0.65; 95% CI: 0.41 to 1.03; p = 0.068). CONCLUSIONS: Although we cannot prove a statistically reliable effect of intravenous IgM-enriched immunoglobulins, the confidence intervals may suggest a clinically relevant effect in certain subgroups. Here, an early administration (i.e. in critically ill but not yet mechanically ventilated COVID-19 patients) and a dose of ≥ 15 g for at least 3 days may confer beneficial effects without concerning safety issues. However, these findings need to be validated in upcoming randomized clinical trials. Trial registration DRKS00025794 , German Clinical Trials Register, https://www.drks.de . Registered 6 July 2021.

Left ventricular assist device implantation causes platelet dysfunction and proinflammatory platelet-neutrophil interaction.

Blood flow through left ventricular assist devices (LVAD) may induce activation and dysfunction of platelets. Dysfunctional platelets cause coagulation disturbances and form platelet-neutrophil conjugates (PNC), which contribute to inflammatory tissue damage. This prospective observational cohort study investigated patients, who underwent implantation of a LVAD (either HeartMate II (HM II) (n = 7) or HeartMate 3 (HM 3) (n = 6)) and as control patients undergoing coronary artery bypass grafting (CABG) and/or aortic valve replacement (AVR) (n = 10). We performed platelet and leukocyte flow cytometry, analysis of platelet activation markers, and platelet aggregometry. Platelet CD42b expression was reduced at baseline and perioperatively in HM II/3 compared to CABG/AVR patients. After surgery the platelet activation marker ß-thromboglobulin and platelet microparticles increased in all groups while platelet aggregation decreased. Platelet aggregation was more significantly impaired in LVAD compared to CABG/AVR patients. PNC were higher in HM II compared to HM 3 patients. We conclude that LVAD implantation is associated with platelet dysfunction and proinflammatory platelet-leukocyte binding. These changes are less pronounced in patients treated with the newer generation LVAD HM 3. Future research should identify device-specific LVAD features, which are associated with the least amount of platelet activation to further improve LVAD therapy.

A one-day focused cardiac ultrasound training has a limited impact on residents' abilities to visually assess right ventricular dimensions and function.

BACKGROUND: Focused cardiac ultrasound (FCU) is a helpful tool to rapidly identify right ventricular (RV) causes of hemodynamic instability and facilitate the initiation of therapy. The clinical value of existing course models often remains unclear. This study investigated the effects of a one-day FCU training on the visual estimation skills of RV characteristics. METHODS: Four residents were included as the study group after completing a standardized one-day FCU training. Four gender-matched controls did not take part in the training. All residents graded image quality, RV systolic function, and RV dimensions in a test comprising 35 ultrasound clips. RESULTS: The study and control group did not differ in ICU or ultrasound experience. Overall, training participants were able to distinguish between good and insufficient image quality significantly better than the control group (agreement 80.0% vs 61.4%, p = 0.04). The agreement for the estimation of RV function and RV dimensions was not different between the groups (63.2% vs 60.5%, p = 0.66 and 64.3% vs 67.1%, p = 0.18, respectively). Descriptively, only small differences were found between the groups for the estimation of RV function and RV dimensions in subgroups of patients with normal versus reduced systolic RV function or normal versus enlarged RV dimensions, respectively. Both groups struggled in identifying RV enlargement (34.6% vs 46.2%). DISCUSSION: In this study, a single one-day FCU training had no impact on residents' skills to visually assess systolic RV function or RV dimensions. Improvements of current training modalities or continuous teaching models are needed to optimize residency programs and patient care.

Identifying the optimal blood pressure for cerebral autoregulation in infants after cardiac surgery by monitoring cerebrovascular reactivity-A pilot study.

BACKGROUND: Advances in the treatment of pediatric congenital heart disease have increased survival rates. Despite efforts to prevent neurological injury, many patients suffer from impaired neurodevelopmental outcomes. Compromised cerebral autoregulation can increase the risk of brain injury following pediatric cardiac surgery with cardiopulmonary bypass. Monitoring autoregulation and maintaining adequate cerebral blood flow can help prevent neurological injury. AIMS: Our objective was to evaluate autoregulation parameters and to define the optimal blood pressure as well as the lower and upper blood pressure limits of autoregulation. METHODS: Autoregulation was monitored prospectively in 36 infants after cardiopulmonary bypass surgery for congenital heart defects between January and December 2019. Autoregulation indices were calculated by correlating invasive arterial blood pressure, cortical oxygen saturation, and relative tissue hemoglobin levels with near-infrared spectroscopy parameters. RESULTS: The mean patient age was 4.1 ± 2.8 months, and the mean patient weight was 5.2 ± 1.8 kg. Optimal mean arterial pressure could be identified in 88.9% of patients via the hemoglobin volume index and in 91.7% of patients via the cerebral oxygenation index, and a lower limit of autoregulation could be found in 66.7% and 63.9% of patients, respectively. No significant changes in autoregulation indices at the beginning or end of the monitoring period were observed. In 76.5% ± 11.1% and 83.8% ± 9.9% of the 8 and 16 h monitoring times, respectively, the mean blood pressure was inside the range of intact autoregulation (below in 21.5% ± 25.4% and 11.3% ± 16.5% and above in 8.7% ± 10.4% and 6.0% ± 11.0%, respectively). The mean optimal blood pressure was 57.4 ± 8.7 mmHg and 58.2 ± 7.9 mmHg and the mean lower limit of autoregulation was 48.8 ± 8.3 mmHg and 45.5 ± 6.7 mmHg when generated via the hemoglobin volume index and cerebral oxygenation index, respectively. CONCLUSIONS: Postoperative noninvasive autoregulation monitoring after cardiac surgery in children can be reliably and safely performed using the hemoglobin volume index and cerebral oxygenation index and provides robust data. This monitoring can be used to identify individual hemodynamic targets to optimize autoregulation, which differs from those recommended in the literature. Further evaluation of this subject is needed.

Impact of Whole-Body Perfusion in Postoperative Outcomes After Aortic Arch Reconstruction Surgery in Neonates and Infants.

INTRODUCTION: The aim of this study was to determine whether whole-body perfusion (WBP) consisting of a combined antegrade cerebral perfusion (ACP) and lower body perfusion (LBP) improves the outcome after aortic arch reconstruction surgery in neonates compared with ACP. METHODS: Sixty-five consecutive patients under one year of age who underwent aortic arch reconstruction as the main procedure or as part of a more complex surgery from 2014-2020 in our center were included. The patients were separated into two groups, according to the perfusion strategy, either ACP (34 patients) as the control group or WBP (31 patients) as the intervention group. LBP was achieved through an arterial sheath in the femoral artery. Outcome parameters were postoperative renal, gastrointestinal, and neurological complications and 30-day mortality. RESULTS: The patients in the WBP group showed lower intraoperative lactate levels and close to normal early postoperative renal and hepatic enzymes and LDH at PICU admission compared with the patients in the ACP group. The number of patients suffering from postoperative neurological complications and multiorgan failure was lower in the WBP group. CONCLUSION: In our experience, the combined use of ACP and LBP through the femoral artery showed an improvement, regarding postoperative neurologic complications in neonates and infants undergoing aortic arch surgery.

[Perioperative Role of Echocardiography and its Influence on Surgical Management]. / Einfluss der perioperativen Echokardiografie auf das chirurgische Management.

Perioperative echocardiography is an important puzzle piece for surgical management especially in the area of cardiovascular surgery. This imaging technique is not only used to confirm preoperatively made diagnoses but also for morphological and functional assessment of cardiac structures and verification of surgical or interventional results. Moreover, echocardiography is used for hemodynamic monitoring and guidance of pharmacological therapy. This article gives an overview of the impact of echocardiography on surgical management from a clinical point of view. Indications and contraindications are discussed as well as the use of echocardiography during the different phases of surgery and intensive care. The possible influence of the echocardiographic finding on modification of the surgical approach is presented based on a case example and underlined by clinical tips and tricks.

Routine Detachment of the Anterior and Septal Tricuspid Leaflets Simplifies VSD Closure and Improves the Outcomes.

Background and Objectives: The closure of perimembranous ventricular septal defects (VSDs) is one of the most common surgeries performed in infancy. The technique of detachment of the anterior and septal leaflets of the tricuspid valve (TV) with subsequent leaflet augmentation is frequently used for isolated as well as non-isolated VSD closure. In this study, we compared the incidence of tricuspid regurgitation (TR) in patients who underwent a VSD repair with and without detachment of the TV in the short- and long-term follow-up. Materials and Methods: A retrospective study that included 140 patients who underwent perimembranous VSD closure at our center from 2011-2016, where 102 of these patients underwent the procedure with detachment of the TV, was performed. The follow-up data were obtained from postoperative echocardiography performed in the follow-up visits. A total of 62 patients underwent follow-up at our center, where the follow-up time ranged from 1 to 9 years, with a mean of 71 ± 2.47 months. Results: Regarding patients who underwent a VSD repair with a detachment of the TV, 98.1% of the patients had none to mild TR, compared to 94.7% in patients without intraoperative TV detachment at the time of discharge. There were no reported cases of moderate to severe TR, atrioventricular blocks, aortic insufficiency, or deaths. A total of 98.1% of patients who underwent follow-up at our center with a TV detachment had none to mild TR compared to 94.7% in the group without TV detachment. Conclusion: TV detachment with leaflet augmentation for VSD closure is safe and effective and does not increase the incidence of TR in the short- and long-term follow-up.

Machine learning identifies ICU outcome predictors in a multicenter COVID-19 cohort.

BACKGROUND: Intensive Care Resources are heavily utilized during the COVID-19 pandemic. However, risk stratification and prediction of SARS-CoV-2 patient clinical outcomes upon ICU admission remain inadequate. This study aimed to develop a machine learning model, based on retrospective & prospective clinical data, to stratify patient risk and predict ICU survival and outcomes. METHODS: A Germany-wide electronic registry was established to pseudonymously collect admission, therapeutic and discharge information of SARS-CoV-2 ICU patients retrospectively and prospectively. Machine learning approaches were evaluated for the accuracy and interpretability of predictions. The Explainable Boosting Machine approach was selected as the most suitable method. Individual, non-linear shape functions for predictive parameters and parameter interactions are reported. RESULTS: 1039 patients were included in the Explainable Boosting Machine model, 596 patients retrospectively collected, and 443 patients prospectively collected. The model for prediction of general ICU outcome was shown to be more reliable to predict "survival". Age, inflammatory and thrombotic activity, and severity of ARDS at ICU admission were shown to be predictive of ICU survival. Patients' age, pulmonary dysfunction and transfer from an external institution were predictors for ECMO therapy. The interaction of patient age with D-dimer levels on admission and creatinine levels with SOFA score without GCS were predictors for renal replacement therapy. CONCLUSIONS: Using Explainable Boosting Machine analysis, we confirmed and weighed previously reported and identified novel predictors for outcome in critically ill COVID-19 patients. Using this strategy, predictive modeling of COVID-19 ICU patient outcomes can be performed overcoming the limitations of linear regression models. Trial registration "ClinicalTrials" (clinicaltrials.gov) under NCT04455451.

Extubation and Noninvasive Ventilation of Patients Supported by Extracorporeal Life Support for Cardiogenic Shock: A Single-Center Retrospective Observational Cohort Study.

BACKGROUND: Temporary extracorporeal life support (ECLS) by venoarterial extracorporeal membrane oxygenation is an emerging therapy for patients with severe, ongoing cardiogenic shock. After stabilization of the hemodynamic status and end-organ function, sedation weaning, extubation, and noninvasive ventilation (NIV) can be attempted. The goal of this study was to analyze the feasibility of extubation and NIV during versus after ECLS for cardiogenic shock. METHODS: Single-center retrospective observational study of 132 patients undergoing ECLS due to severe cardiogenic shock between January 2015 and December 2016 at a tertiary care university hospital. RESULTS: Patients received ECLS due to acute myocardial infarction (20.6%), ongoing cardiogenic shock (15.2%), postoperative low-cardiac-output syndrome (24.2%), and extracorporeal cardiopulmonary resuscitation (40.2%). Overall, intensive care unit survival was 44.7%. Sixty-nine (52.3%) patients could never be extubated. Forty-three (32.6%) were extubated while on ECLS support (group 1) and 20 (15.1%) were extubated after weaning from ECLS (group 2). Patients extubated during ECLS had a significantly shorter total time on ventilator (P = .003, mean difference: -284 hours [95% confidence limits: -83 to -484]) and more invasive ventilation free days (P = .0018; mean difference 8 days [95%CL: 2-14]). Mortality and NIV failure rates were similar between groups. CONCLUSIONS: Extubation and NIV are feasible in patients who stabilize during ECLS therapy. Further studies need to address whether extubation has the potential to improve patients outcome or if the feasibility to extubate is a surrogate for disease severeness.

Mesenchymal Stem Cell Therapy for Severe COVID-19 ARDS.

BACKGROUND: The COVID-19 pandemic reached Germany in spring 2020. No proven treatment for SARS-CoV-2 was available at that time, especially for severe COVID-19-induced ARDS. We determined whether the infusion of mesenchymal stromal cells (MSCs) would help to improve pulmonary function and overall outcome in patients with severe COVID-19 ARDS. We offered MSC infusion as an extended indication to all critically ill COVID-19 patients with a Horovitz index <100. We treated 5 out of 23 patients with severe COVID-19 ARDS with an infusion of MSCs. One million MSCs/kg body weight was infused over 30 minutes, and the process was repeated in 3 patients twice and in 2 patients 3 times. RESULT: Four out of 5 MSC-treated patients compared to 50% of control patients (9 out of 18) received ECMO support (80%). The MSC group showed a higher Murray score on admission than control patients, reflecting more severe pulmonary compromise (3.5 ± 0.2 versus 2.8 ± 0.3). MSC infusion was safe and well tolerated. The MSC group had a significantly higher Horovitz score on discharge than the control group. Compared to controls, patients with MSC treatment showed a significantly lower Murray score upon discharge than controls. In the MSC group, 4 out of 5 patients (80%) survived to discharge and exhibited good pulmonary function, whereas only 8 out of 18 patients (45%) in the control group survived to discharge. CONCLUSION: MSC infusion is a safe treatment for COVID-19 ARDS that improves pulmonary function and overall outcome in this patient population.

Left ventricular unloading with transaortic Impella 2.5 implantation in a pediatric patient supported by extracorporeal life support.

We report the case of a 12-year old female patient with Friedreich's ataxia and diabetes mellitus. Due to a progressive multiorgan failure, a veno-arterial extracorporeal membrane oxygenation was implanted through the axillary vessels. However, due to a lack of ejection and severe dilatation of the left ventricle, an Impella 2.5 was implanted. Due to the small diameter of the femoral arteries, we performed a trans-aortic implantation through a median sternotomy via a Dacron tube graft. We report on the procedure and perioperative outcome.

[Vasopressors: Physiology, Pharmacology and Clinical Applications]. / Vasopressoren: Physiologie, Pharmakologie und klinischer Einsatz.

Vasopressors are widely used in anaesthesiology and critical care medicine, to treat harmless (e.g. anaesthesia-induced hypotension) as well as life-threatening conditions (e.g. septic shock). Some clinically used vasopressors resemble endogenous substances - such as norepinephrine - while others have been artificially synthesized (e.g. phenylephrine). Most of the substances used in different clinical scenarios have various effects except for vasoconstriction alone. Therefore, a thorough understanding of the pharmacology and clinical profile of every single substance is of highest importance prior to practical usage. Furthermore, the fundamentals of vascular physiology and vasotonic regulation are mandatory to safely provide vasopressor-based therapies. This article covers the essentials of physiology and pharmacology of vasopressors, and the clinical settings they are used in (e.g. septic shock, vasoplegic shock after cardiac surgery, trauma-induced hypotension).

Non-Invasive Cerebral Autoregulation Monitoring During Awake Carotid Endarterectomy Identifies Clinically Significant Brain Ischaemia.

OBJECTIVE: The aim was to evaluate the potential of near infrared spectrometry (NIRS) monitoring enhanced by autoregulation parameters to detect clamp ischaemia during awake carotid endarterectomy (CEA). METHODS: This was a prospective, hypothesis generating, single centre observational study. Fifty-nine consecutive patients with carotid artery stenosis, of whom 15 (25%) were symptomatic, were enrolled. The patients underwent awake CEA with NIRS monitoring. Regional oxygen saturation (rSO2), relative tissue haemoglobin concentration (rTHb), and mean arterial blood pressure were captured by ICM + software (University of Cambridge Enterprise, Cambridge, UK). The cerebral oxygenation index (COx) and haemoglobin volume index (HVx) were calculated continuously. Two groups were formed depending on neurological symptoms: a symptomatic group with shunt insertion (shunt) and an asymptomatic group (no shunt). RESULTS: Eight patients (14%) became symptomatic and needed intra-operative shunting. The decrease in ipsilateral rSO2 was higher in the shunt group (13.5% vs. 5.3%) and rTHB increased on the non-operated side (+0.05 ± 0.01; p = .016). In symptomatic patients no significant change in rTHB was found during clamping, whereas in asymptomatic patients there was a bilateral increase (ipsilateral: + 0.06 [p = .022]; contralateral: + 0.06 [p = .010]). In asymptomatic patients, ipsilateral COx decreased after clamping (-0.06 ± 0.02; p = .024), indicating functional autoregulation. In symptomatic patients, ipsilateral COx increased to 0.32 (+0.19 ± 0.05; p = .048), indicating loss of autoregulation. Accordingly, pooled ipsilateral and contralateral data showed increasing HVx and COx in symptomatic patients (HVx, p < .001; COx, p = .039). CONCLUSION: In addition to a drop in rSO2, the loss of autoregulatory capacity may be useful in identifying clinically significant clamping ischaemia during CEA under general anaesthesia and may allow optimisation of blood pressure management during awake CEA.

Acute changes of global and longitudinal right ventricular function: an exploratory analysis in patients undergoing open-chest mitral valve surgery, percutaneous mitral valve repair and off-pump coronary artery bypass grafting.

BACKGROUND: Right ventricular (RV) function is an important prognostic indicator. The acute effects of cardiac interventions or cardiac surgery on global and longitudinal RV function are not entirely understood. In this study, acute changes of RV function during mitral valve surgery (MVS), percutaneous mitral valve repair (PMVR) and off-pump coronary artery bypass surgery (OPCAB) were investigated employing 3D echocardiography. METHODS: Twenty patients scheduled for MVS, 23 patients scheduled for PMVR and 25 patients scheduled for OPCAB were included retrospectively if patients had received 3D transesophageal echocardiography before and immediately after MVS, PMVR or OPCAB, respectively. RV global and longitudinal function was assessed using a 3D multiparameter set consisting of global right ventricular ejection fraction (RVEF), tricuspid annular plane systolic excursion (TAPSE), longitudinal contribution to RVEF (RVEFlong) and free wall longitudinal strain (FWLS). RESULTS: Longitudinal RV function was significantly depressed immediately after MVS, as reflected by all parameters (RVEFlong: 20 ± 5% vs. 13 ± 6%, p <  0.001, TAPSE: 13.1 ± 5.1 mm vs. 11.0 ± 3.5 mm, p = 0.04 and FWLS: -20.1 ± 7.1% vs. -15.4 ± 5.1%, p <  0.001, respectively). The global RVEF was slightly impaired, but the difference did not reach significance (37 ± 13% vs. 32 ± 9%, p = 0.15). In the PMVR group, both global and longitudinal RV function parameters were unaltered, whereas the OPCAB group showed a slight reduction of RVEFlong only (18 ± 7% vs. 14 ± 5%, p <  0.01). RVEFlong yielded moderate case-to-case but good overall reproducibility. CONCLUSIONS: TAPSE, FWLS and RVEFlong reflect the depression of longitudinal compared to global RV function initially after MVS. PMVR alone had no impact, while OPCAB had a slight impact on longitudinal RV function. The prognostic implications of these phenomena remain unclear and require further investigation.

Selective lower body perfusion during aortic arch surgery in neonates and small children.

INTRODUCTION: Aortic arch reconstruction surgery represents a challenge for the medical personnel involved in treatment. Along the years, the perfusion strategies for aortic arch reconstruction have evolved from deep hypothermic cardiac arrest to antegrade cerebral perfusion with moderate hypothermia, and recently to a combined cerebral and lower body perfusion with moderate hypothermia. To achieve a lower body perfusion, several cannulation strategies have been described. In this study, we investigated the feasibility of utilizing an arterial sheath introduced in the femoral artery to achieve an effective lower body perfusion. METHODS: We included patients who underwent an aortic arch reconstruction surgery with a lower body perfusion, from January 2017 to June 2019. To achieve a lower body perfusion, a three-way stopcock was connected to the arterial line, where one end was connected to the central cannulation for cerebral perfusion and the other to an arterial sheath that was introduced through the femoral artery. A total of 25 patients were included. Peri- and postoperative lactate and creatinine levels and signs of malperfusion were recorded. RESULTS: During the reperfusion phase, after selective perfusion ended none of the patients showed a significant increase in lactate, creatinine, and liver enzyme levels. After 24 hours, there were no signs of an acute kidney injury, femoral vessel injury, or limb malperfusion. CONCLUSION: These findings show that a sufficient lower body perfusion through an arterial sheath placed in the femoral artery for aortic arch reconstruction can be achieved. This approach caused no complications related to the arterial sheath during the early postoperative period and is an easy way to maintain perfusion of systemic organs.

Perioperative Assessment of Cerebral Oxygen Metabolism in Infants With Functionally Univentricular Hearts Undergoing the Bidirectional Cavopulmonary Connection.

OBJECTIVES: The transition from single-ventricle lesions with surgically placed systemic-to-pulmonary artery shunt to the circulation following a bidirectional cavopulmonary connection results in higher pressure in the superior vena cava when compared with the preceding circulation. The aim of this study was to evaluate the impact of this transition on the perioperative cerebral oxygen metabolism. DESIGN: Prospective observational cohort study. SETTING: Pediatric critical care unit of a tertiary referral center. PATIENTS: Sixteen infants after bidirectional cavopulmonary connection. INTERVENTION: Cardiac surgery (bidirectional cavopulmonary connection). MEASUREMENTS AND MAIN RESULTS: We measured regional cerebral oxygen saturation, amount of hemoglobin, blood flow velocity, and microperfusion immediately before, 12-24 hours, and 36-48 hours following bidirectional cavopulmonary connection. Based on these measurements, we calculated cerebral fractional tissue oxygen extraction and approximated cerebral metabolic rate of oxygen. Mean pressure in the superior vena cava increased significantly (8 vs 17 mm Hg; p < 0.001) following bidirectional cavopulmonary connection. Mean cerebral oxygen saturation increased from 49.0% (27.4-61.0) to 56.9% (39.5-64.0) (p = 0.008), whereas mean cerebral blood flow velocity decreased from 80.0 arbitrary units (61.9-93.0) to 67.3 arbitrary units (59.0-83.3) (p < 0.001). No change was found in the cerebral amount of hemoglobin and in the cerebral microperfusion. Mean cerebral fractional tissue oxygen extraction (0.48 [0.17-0.63] vs 0.30 [0.19-0.56]; p = 0.006) and approximated cerebral metabolic rate of oxygen (5.82 arbitrary units [2.70-8.78] vs 2.27 arbitrary units [1.19-7.35]; p < 0.001) decreased significantly. CONCLUSIONS: Establishment of bidirectional cavopulmonary connection is associated with postoperative improvement in cerebral oxygen metabolism. Cerebral amount of hemoglobin did not increase, although creation of the bidirectional cavopulmonary connection results in significant elevation in superior vena cava pressure. Improvement in cerebral oxygen metabolism was due to lower cerebral blood flow velocity and stable microperfusion, which may indicate intact cerebral autoregulation.

The effects of anesthesia induction and positive pressure ventilation on right-ventricular function: an echocardiography-based prospective observational study.

BACKGROUND: General anesthesia induction with the initiation of positive pressure ventilation creates a vulnerable phase for patients. The impact of positive intrathoracic pressure on cardiac performance has been studied but remains controversial. 3D echocardiography is a valid and MRI-validated bed-side tool to evaluate the right ventricle (RV). The aim of this study was to assess the impact of anesthesia induction (using midazolam, sufentanil and rocuronium, followed by sevoflurane) with positive pressure ventilation (PEEP 5, tidal volume 6-8 ml/kg) on 2D and 3D echocardiography derived parameters of RV function. METHODS: A prospective observational study on fifty-three patients undergoing elective cardiac surgery in a tertiary care university hospital was designed. Transthoracic echocardiography exams were performed before and immediately after anesthesia induction and were recorded together with hemodynamic parameters and ventilator settings. RESULTS: After anesthesia induction TAPSE (mean difference - 1.6 mm (95% CI - 2.6 mm to - 0.7 mm; p = 0.0013) as well as the Tissue Doppler derived tricuspid annulus peak velocity (TDITVs') were significantly reduced (mean difference - 1.9% (95% CI: - 2.6 to - 1.2; p < 0.0001), but global right ventricular ejection fraction (RVEF; p = 0.1607) and right ventricular stroke volume (RVSV; p = 0.1838) did not change. CONCLUSIONS: This data shows a preserved right ventricular ejection fraction and right ventricular stroke volume after anesthesia induction and initiation of positive pressure ventilation. However, the baso-apical right ventricular function is significantly reduced. Larger studies are needed in order to determine the clinical impact of these findings especially in patients presenting with impaired right ventricular function before anesthesia induction. TRIAL REGISTRATION: Retrospecitvely registered, 6th June 2016, ClinicalTrials.gov Identifier NCT02820727 .

Regional Right Ventricular Volume and Function Analysis Using Intraoperative 3-Dimensional Echocardiography-Derived Mesh Models.

OBJECTIVES: In daily echocardiographic practice, the right ventricle (RV) is assessed using mostly 2-dimensional (2D) echocardiography. Parameters measuring longitudinal shortening (eg, tricuspid annular plane systolic excursion) or changes in areas (eg, fractional area change) are used as surrogates for right ventricular function. Three-dimensional (3D) echocardiography-based techniques allow for cardiac magnetic resonance imaging-validated assessment of the RV. Depiction of regional right ventricular function is of increasing clinical interest. This study aimed to calculate regional volumetric changes in the right ventricular inlet, apical section, and outflow tract. Correlations between traditional parameters and regional right ventricular function were studied. DESIGN: Retrospective cohort study on patients scheduled for cardiac surgery. SETTING: Tertiary care university hospital. PARTICIPANTS: The study comprised 80 patients scheduled for cardiac surgery. MEASUREMENTS AND MAIN RESULTS: Based on 3D echocardiographic datasets, mesh models of the RV were generated on a vendor-independent platform. The meshes were further cut into the following 3 regions: the inlet part, the apical section, and the outflow tract. The regional volumes and ejection fractions were compared with the global right ventricular and left ventricular functions. Regional volumes were correlated linearly with the global end-diastolic volume. The right ventricular outflow tract demonstrated a significantly lower ejection fraction than the inlet part (34% ± 11% v 28% ± 11%; p = 0.0054). The function in the right ventricular outflow tract was reduced significantly compared with the global right ventricular function in patients with severely reduced left ventricular ejection fraction (<20%). CONCLUSION: The different parts of the RV seem to have different ejection fractions. Different regions of the RV are affected differently by reduced left ventricular ejection fraction. Regional right ventricular analyses could help clinicians better understand pathologic states of the RV.