Survey on the Updated German S3 Guideline for Intensive Care in Cardiac Surgery Patients.

BACKGROUND: The German guideline on intensive care treatment of cardiac surgical patients provides evidence-based recommendations on management and monitoring. It remains unclear if, respectively, to which degree the guidelines are implemented into the daily practice. Therefore, this study aims to characterize the implementation of guideline recommendations in German cardiac surgical intensive care units (ICUs). METHODS: An internet-based online survey (42 questions, 9 topics) was sent to 158 German head physicians of cardiac surgical ICUs. To compare the effect over time, most questions were based on a previously performed survey (2013) after introduction of the last guideline update in 2008. RESULTS: A total of n = 65 (41.1%) questionnaires were included. Monitoring changed to increased provision of available transesophageal echocardiography specialists in 86% (2013: 72.6%), SvO2 measurement in 93.8% (2013: 55.1%), and electroencephalography in 58.5% (2013: 2.6%). The use of hydroxyethyl starch declined (9.4% vs. 2013: 38.7%), gelatin 4% presented the most administered colloid with 23.4% (2013: 17.4%). Low cardiac output syndrome was primarily treated with levosimendan (30.8%) and epinephrine (23.1%), while norepinephrine (44.6%) and dobutamine (16.9%) represented the most favored drug combination. The main way of distribution was web-based (50.9%), with increasing impact on therapy regimens (36.9% vs. 2013: 24%). CONCLUSION: Changes were found in all questioned sectors compared with the preceding survey, with persisting variability between ICUs. Recommendations of the updated guideline have increasingly entered clinical practice, with participants valuing the updated publication as clinically relevant.

A classification system for pulmonary artery catheters.

Flow-directed, balloon-tipped pulmonary artery catheters allow measuring cardiac output and other haemodynamic variables including intracardiac pressures. We propose classifying pulmonary artery catheters by generations and specifying additional measurement modalities. Based on the method used to measure cardiac output, pulmonary artery catheters can be classified into three generations: first-generation using intermittent pulmonary artery thermodilution; second-generation using a thermal filament for automated pulmonary artery thermodilution; and third-generation combining thermal filament-based automated pulmonary artery thermodilution and pulmonary artery pulse wave analysis. Each of these pulmonary artery catheter generations can include additional measurements, such as continuous mixed venous oxygen saturation, right ventricular ejection fraction and end-diastolic volume, and right ventricular pressure. This classification should help define indications for pulmonary artery catheters in clinical practice and research.

Influence of timing of Levosimendan administration on outcomes in cardiac surgery.

Purpose: Though a subgroup analysis has shown improved survival for patients suffering severely reduced ventricular function undergoing coronary artery bypass grafting, RCTs were not able to demonstrate overall beneficial effects of perioperative Levosimendan in cardiac surgery. This might be due to Levosimendan's pharmacokinetics reaching a steady-state concentration only 4-8 h after administration. Thus, this study now analysed the influence of timing of Levosimendan administration on perioperative outcome in cardiac surgery patients preoperatively presenting with severely reduced ventricular function and therefore considered at high-risk for intra- or postoperative low cardiac output syndrome. We hypothesized that prolonged preoperative Levosimendan administration ("preconditioning") would reduce mortality. Methods: All adult patients undergoing cardiac surgery between 2006 and 2018 perioperatively receiving Levosimendan were included in this retrospective, observational cohort study (n = 498). Patients were stratified into 3 groups: Levosimendan started on the day prior to surgery ("preop"), Levosimendan started on the day of surgery ("intraop") or post ICU admission ("postop"). After propensity score matching (PSM) was performed, outcomes defined according to proposed standard definitions for perioperative outcome research were compared between groups. Results: After PSM, there were no significant differences in patients' characteristics, comorbidities and type/priority of surgery between groups. Compared to intraop or postop Levosimendan treatment, preop treated patients had significantly lower in-hospital-mortality (preop vs. intraop. vs. postop = 16,7% vs. 33,3% vs. 42,3%), duration of mechanical ventilation and rate of continuous renal replacement therapy. Conclusions: Prolonged preoperative treatment with Levosimendan of cardiac surgery patients preoperatively presenting with severely reduced left ventricular function might be beneficial in terms of postoperative outcome. Our results are in line with recent experts' recommendations concerning the prolonged perioperative use of Levosimendan. We strongly recommend that future randomized trials include this "preconditioning" treatment as an experimental arm.

[Cardioanaesthesiology - What's new?] / Kardioanästhesie ­ Was gibt es Neues?

The still unchanged high morbidity and mortality of patients undergoing complex cardiac surgical procedures as well as developments in minimally invasive cardiac surgery are not only an ongoing challenge for all working in cardiac anaesthesia but also a chance for further developing this anaesthetic subdiscipline. Alongside the presentation of a case report, the present article gives an overview about recent developments in inotropic therapy, monitoring, the rational use of mechanical circulatory support, volume therapy, sedation, analgesia, and point-of-care coagulation monitoring in cardiac anaesthesia.

A comparison of the NeurOs® and the INVOS 5100C® cerebral oximeter during variations of the partial pressure of carbon dioxide and fractional inspiratory concentration of oxygen.

This prospective method comparison study compared cerebral oxygen saturation (ScO2) measurement performance of the new cerebral oximeter (NeurOs®, Mespere LifeSciences, Ontario, Canada) in comparison to the established INVOS 5100C® (Medtronic, Boulder, USA) cerebral oximeter. We performed measurements during different levels of carbon dioxide pressure (PaCO2) during hyper- and hypoventilation and different levels of arterial oxygen saturation (SaO2) induced by variation of the inspiratory fraction of oxygen (FiO2). 59 anesthetized cardiac and vascular surgical patients were studied during hemodynamically stable conditions. Two versions of the NeurOs® oximeter were used in 39 and 20 patients, respectively: an older version with one bi-hemispherical sensor attached to the midline of the forehead and a newer version with two sensors that were attached to the left and right forehead. Alternating measurements of ScO2 with the INVOS® oximeter (bifrontal sensors) and the NeurOs® oximeter were performed during baseline conditions and after PaCO2 had been randomly in- and decreased by changes in ventilation (constant FiO2) and SaO2 had been randomly modified by variations in FiO2 (constant PaCO2). Employing the most recent NeurOs® version, measurements were additionally performed in a default and a high penetration mode. Bland-Altman analyses revealed comparable bias and limits of agreement for INVOS® and NeurOS® measurements during baseline conditions when using the bi-hemispherical sensor and the version with two sensors, respectively. Consequently, further analyses were performed on the pooled data of 59 patients. Bland-Altman analysis for repeated measurements revealed a bias of - 0.5%, a lower limit of agreement of - 16.3% (95% CI - 19.6 to - 13.7%) and an upper limit of agreement of 15.4% (95% CI 12.8 to 18.8%) during variations of PaCO2. The respective analysis during changes in SaO2 induced by variation of the FiO2 revealed a bias of - 0.8%, a lower limit of agreement of - 16.3% (95% CI - 19.7 to - 13.6%) and an upper limit of agreement of 14.7% (95% CI 12.1 to 18.2%). Both analyses showed a proportional error. No significant differences in ScO2 were observed during measurements with the bi-frontal sensors in the default as well as the high penetration mode. The ScO2 measurement performance of the NeurOs® cerebral oximeter is not interchangeable with the INVOS® cerebral oximeter during variations of ventilation and oxygenation in elective cardiac or vascular surgical patients. The lack of reactivity to changes in ventilation (by variation of PaCO2) and oxygen delivery (by variation of FiO2) question the reliability of NeurOs® measurements to reflect changes in cerebral blood flow and cerebral oxygen balance. This holds true not only for different sensor positions at the forehead but also for different modes of penetration.

Prophylactic levosimendan in patients with low ejection fraction undergoing coronary artery bypass grafting: A pooled analysis of two multicentre randomised controlled trials.

OBJECTIVES: To assess the effect of preoperative levosimendan on mortality at day 90 in patients with left ventricular ejection fraction (LVEF) ≤ 40%, and to investigate a possible differential effect between patients undergoing isolated coronary artery bypass grafting (CABG) versus CABG combined with valve replacement surgery. DESIGN: Pooled analysis of two multicentre randomised controlled trials (RCT) investigating prophylactic levosimendan versus placebo prior to CABG surgery on mortality at day 90 in patients with LVEF ≤ 40%. A meta-analysis of all RCT investigating the same issue was also conducted. RESULTS: A cohort of 1084 patients (809 isolated CABG, and 275 combined surgery) resulted from the merging of LEVO-CTS and LICORN databases. Seventy-two patients were dead at day 90. The mortality at day 90 was not different between levosimendan and placebo (Hazard Ratio (HR): 0.73, 95% CI: 0.41-1.28, p = 0.27). However, there was a significant interaction between the type of surgery and the study drug (p = 0.004). We observed a decrease in mortality at day 90 in the isolated CABG subgroup (HR: 0.39, 95% CI: 0.19-0.82, p = 0.013), but not in the combined surgery subgroup (HR: 1.73, 95% CI: 0.77-3.92, p = 0.19). The meta-analysis of 6 RCT involving 1441 patients confirmed the differential effect on mortality at day 30 between the 2 subgroups. CONCLUSIONS: Preoperative levosimendan did not reduce mortality in a mixed surgical population with LV dysfunction. However, the subgroup of patients undergoing isolated CABG had a reduction in mortality at day 90, whereas there was no significant effect in combined surgery patients. This finding requires confirmation with a specific prospective trial.

High Central Venous Pressure after Cardiac Surgery Might Depict Hemodynamic Deterioration Associated with Increased Morbidity and Mortality.

BACKGROUND: Cardiac surgery patients represent a high-risk cohort in intensive care units (ICUs). Central venous pressure (CVP) measurement seems to remain an integral part in hemodynamic monitoring, especially in cardio-surgical ICUs. However, its value as a prognostic marker for organ failure is still unclear. Therefore, we analyzed postoperative CVP values after adult cardiac surgery in a large cohort with regard to its prognostic value for morbidity and mortality. METHODS: All adult patients admitted to our ICUs between 2006 and 2019 after cardiac surgery were eligible for inclusion in the study (n = 11,198). We calculated the median initial CVP (miCVP) after admission to the ICU, which returned valid values for 9802 patients. An ROC curve analysis for optimal cut-off miCVP to predict ICU mortality was conducted with consecutive patient allocation into a (a) low miCVP (LCVP) group (≤11 mmHg) and (b) high miCVP (HCVP) group (>11 mmHg). We analyzed the impact of high miCVP on morbidity and mortality by propensity score matching (PSM) and logistic regression. RESULTS: ICU mortality was increased in HCVP patients. In addition, patients in the HCVP group required longer mechanical ventilation, had a higher incidence of acute kidney injury, were more frequently treated with renal replacement therapy, and showed a higher risk for postoperative liver dysfunction, parametrized by a postoperative rise of ≥ 10 in MELD Score. Multiple regression analysis confirmed HCVP has an effect on postoperative ICU-mortality and intrahospital mortality, which seems to be independent. CONCLUSIONS: A high initial CVP in the early postoperative ICU course after cardiac surgery is associated with worse patient outcome. Whether or not CVP, as a readily and constantly available hemodynamic parameter, should promote clinical efforts regarding diagnostics and/or treatment, warrants further investigations.

Still a place for aortic counterpulsation in cardiac surgery and patients with cardiogenic shock?

This article is one of ten reviews selected from the Annual Update in Intensive Care and Emergency Medicine 2021. Other selected articles can be found online at https://www.biomedcentral.com/collections/annualupdate2021 . Further information about the Annual Update in Intensive Care and Emergency Medicine is available from https://link.springer.com/bookseries/8901 .

[Solutions for Fluid Treatment and Outcome - an Update]. / Substanzen zur Flüssigkeitstherapie und Outcome ­ ein Update.

Fluid therapy is one of the most frequently used medical interventions with the aim of normalizing the fluid balance. A decisive criterion for the efficiency of fluid or volume replacement is the functionality of the glycocalyx, a thin endothelial glycoprotein layer. Its solidity is an essential factor for fluid exchange and transport from the vascular system to the tissue. The recently described revised Starling principle extends the understanding considerably. From a clinical point of view, fluid treatment should aim for timely euvolemia without inducing relevant side effects. Both crystalloid and natural or synthetic colloidal solutions are available. In the case of crystalloid solutions, the so-called balanced solutions seem to be associated with fewer side effects. If the vascular barrier is intact, colloid solutions have a higher volume effect, but may have significant side effects limiting their use. At least in Europe, some synthetic colloids shall therefore no longer be used in critically ill patients. In contrast, treatment with albumin 20% in hypalbuminemic patients with cardiovascular disease leads to a reduced incidence of acute kidney injury and has also been associated with other clinical benefits. To what extent future, individualized therapeutic approaches employing colloids will influence the outcome is currently speculative.

Impact of Anesthesia Strategy and Valve Type on Clinical Outcomes After Transcatheter Aortic Valve Replacement.

BACKGROUND: The randomized SOLVE-TAVI (compariSon of secOnd-generation seLf-expandable vs. balloon-expandable Valves and gEneral vs. local anesthesia in Transcatheter Aortic Valve Implantation) trial compared newer-generation self-expanding valves (SEV) and balloon-expandable valves (BEV) as well as local anesthesia with conscious sedation (CS) and general anesthesia (GA) in patients undergoing transfemoral transcatheter aortic valve replacement (TAVR). Both strategies showed similar outcomes at 30 days. OBJECTIVES: The purpose of this study was to compare clinical outcomes during 1-year follow-up in the randomized SOLVE-TAVI trial. METHODS: Using a 2 × 2 factorial design 447 intermediate- to high-risk patients with severe, symptomatic aortic stenosis were randomly assigned to transfemoral TAVR using either the SEV (Evolut R, Medtronic Inc., Minneapolis, Minnesota) or the BEV (Sapien 3, Edwards Lifesciences, Irvine, California) as well as CS or GA at 7 sites. RESULTS: In the valve-comparison strategy, rates of the combined endpoint of all-cause mortality, stroke, moderate or severe paravalvular leakage, and permanent pacemaker implantation were similar between the BEV and SEV group (n = 84, 38.3% vs. n = 87, 40.4%; hazard ratio: 0.94; 95% confidence interval: 0.70 to 1.26; p = 0.66) at 1 year. Regarding the anesthesia comparison, the combined endpoint of all-cause mortality, stroke, myocardial infarction, and acute kidney injury occurred with similar rates in the GA and CS groups (n = 61, 25.7% vs. n = 54, 23.8%; hazard ratio: 1.09; 95% confidence interval: 0.76 to 1.57; p = 0.63). CONCLUSIONS: In intermediate- to high-risk patients undergoing transfemoral TAVR, newer-generation SEV and BEV as well as CS and GA showed similar clinical outcomes at 1 year using a combined clinical endpoint. (SecOnd-generation seLf-expandable Versus Balloon-expandable Valves and gEneral Versus Local Anesthesia in TAVI [SOLVE-TAVI]; NCT02737150).

An update on levosimendan in acute cardiac care: applications and recommendations for optimal efficacy and safety.

Introduction: In the 20 years since its introduction to the palette of intravenous hemodynamic therapies, the inodilator levosimendan has established itself as a valuable asset for the management of acute decompensated heart failure. Its pharmacology is notable for delivering inotropy via calcium sensitization without an increase in myocardial oxygen consumption.Areas covered: Experience with levosimendan has led to its applications expanding into perioperative hemodynamic support and various critical care settings, as well as an array of situations associated with acutely decompensated heart failure, such as right ventricular failure, cardiogenic shock with multi-organ dysfunction, and cardio-renal syndrome. Evidence suggests that levosimendan may be preferable to milrinone for patients in cardiogenic shock after cardiac surgery or for weaning from extracorporeal life support and may be superior to dobutamine in terms of short-term survival, especially in patients on beta-blockers. Positive effects on kidney function have been noted, further differentiating levosimendan from catecholamines and phosphodiesterase inhibitors.Expert opinion:Levosimendan can be a valuable resource in the treatment of acute cardiac dysfunction, especially in the presence of beta-blockers or ischemic cardiomyopathy. When attention is given to avoiding or correcting hypovolemia and hypokalemia, an early use of the drug in the treatment algorithm is preferred.

Vasopressor Therapy in Cardiac Surgery-An Experts' Consensus Statement.

Hemodynamic conditions with reduced systemic vascular resistance commonly are observed in patients undergoing cardiac surgery and may range from moderate reductions in vascular tone, as a side effect of general anesthetics, to a profound vasodilatory syndrome, often referred to as vasoplegic shock. Therapy with vasopressors is an important pillar in the treatment of these conditions. There is limited guidance on the appropriate choice of vasopressors to restore and optimize systemic vascular tone in patients undergoing cardiac surgery. A panel of experts in the field convened to develop statements and evidence-based recommendations on clinically relevant questions on the use of vasopressors in cardiac surgical patients, using a critical appraisal of the literature following the GRADE system and a modified Delphi process. The authors unanimously and strongly recommend the use of norepinephrine and/or vasopressin for restoration and maintenance of systemic perfusion pressure in cardiac surgical patients; despite that, the authors cannot recommend either of these drugs with respect to the risk of ischemic complications. The authors unanimously and strongly recommend against using dopamine for treating post-cardiac surgery vasoplegic shock and against using methylene blue for purposes other than a rescue therapy. The authors unanimously and weakly recommend that clinicians consider early addition of a second vasopressor (norepinephrine or vasopressin) if adequate vascular tone cannot be restored by a monotherapy with either norepinephrine or vasopressin and to consider using vasopressin as a first-line vasopressor or to add vasopressin to norepinephrine in cardiac surgical patients with pulmonary hypertension or right-sided heart dysfunction.

Association between levosimendan, postoperative AKI, and mortality in cardiac surgery: Insights from the LEVO-CTS trial.

OBJECTIVES: We aimed to evaluate the association between levosimendan treatment and acute kidney injury (AKI) as well as assess the clinical sequelae of AKI in cardiac surgery patients with depressed left ventricular function (ejection fraction <35%). METHODS: Patients in the LEVO-CTS trial undergoing on-pump coronary artery bypass grafting (CABG), valve, or CABG/valve surgery were stratified by occurrence and severity of postoperative AKI using the AKIN classification. The association between levosimendan infusion and AKI was modeled using multivariable regression. RESULTS: Among 854 LEVO-CTS patients, 231 (27.0%) experienced postoperative AKI, including 182 (21.3%) with stage 1, 35 (4.1%) with stage 2, and 14 (1.6%) with stage 3 AKI. The rate of AKI was similar between patients receiving levosimendan or placebo. The odds of 30-day mortality significantly increased by AKI stage compared to those without AKI (stage 1: adjusted odds ratio [aOR] 2.0, 95% confidence interval [CI] 0.8-4.9; stage 2: aOR 9.1, 95% CI 3.2-25.7; stage 3: aOR 12.4, 95% CI 3.0-50.4). No association was observed between levosimendan, AKI stage, and odds of 30-day mortality (interaction P = .69). Factors independently associated with AKI included increasing age, body mass index, diabetes, and increasing baseline systolic blood pressure. Increasing baseline eGFR and aldosterone antagonist use were associated with a lower risk of AKI. CONCLUSIONS: Postoperative AKI is common among high-risk patients undergoing cardiac surgery and associated with significantly increased risk of 30-day death or dialysis. Levosimendan was not associated with the risk of AKI.

Reduced left ventricular contractility, increased diastolic operant stiffness and high energetic expenditure in patients with severe aortic regurgitation without indication for surgery.

OBJECTIVES: Recent mortality studies showed worse prognosis in patients (ARNS) with severe aortic regurgitation and preserved ejection fraction (EF) not fulfilling the criteria of current guidelines for surgery. The aim of our study was to analyse left ventricular (LV) systolic and diastolic function and mechanical energetics to find haemodynamic explanations for the reduced prognosis of these patients and to seek a new concept for surgery. METHODS: Global longitudinal strain (GLS) and echo-based single-beat pressure-volume analyses were performed in patients with ARNS (LV end-diastolic diameter <70 mm, EF >50%, GLS > -19% n = 41), with indication for surgery (ARS; n = 19) and in mild hypertensive controls (C; n = 20). Additionally, end-systolic elastance (LV contractility), stroke work and total energy (pressure-volume area) were calculated. RESULTS: ARNS demonstrated significantly depressed LV contractility versus C: end-systolic elastance (1.58 ± 0.7 vs 2.54 ± 0.8 mmHg/ml; P < 0.001), despite identical EF (EF: 59 ± 6% vs 59 ± 7%). Accordingly, GLS was decreased [-15.7 ± 2.7% (n = 31) vs -21.2 ± 2.4%; P < 0.001], end-diastolic volume (236 ± 90 vs 136 ± 30 ml; P < 0.001) and diastolic operant stiffness were markedly enlarged, as were pressure-volume area and stroke work, indicating waste of energy. The correlation of GLS versus end-systolic elastance was good (r = -0.66; P < 0.001). ARNS and ARS patients demonstrated similar haemodynamic disorders, whereas only GLS was worse in ARS. CONCLUSIONS: ARNS patients almost matched the ARS patients in their haemodynamic and energetic deterioration, thereby explaining poor prognosis reported in literature. GLS has been shown to be a reliable surrogate for LV contractility, possibly overestimating contractility due to exhausted preload reserve in aortic regurgitation patients. GLS may outperform conventional echo parameters to predict more precisely the timing of surgery.