A Comparison of Different Intensive Care Unit Definitions Derived from the German Administrative Data Set: A Methodological, Real-World Data Analysis from 86 Helios Hospitals.

Background: The intensive care unit (ICU) is a scarce resource in all health care systems, necessitating a well-defined utilization. Therefore, benchmarks are essential; and yet, they are limited due to heterogenous definitions of what an ICU is. This study analyzed the case distribution, patient characteristics, and hospital course and outcomes of 6,204,093 patients in the German Helios Hospital Group according to 10 derived ICU definitions. We aimed to set a baseline for the development of a nationwide, uniform ICU definition. Methods: We analyzed ten different ICU definitions: seven derived from the German administrative data set of claims data according to the German Hospital Remuneration Act, three definitions were taken from the Helios Hospital Group's own bed classification. For each ICU definition, the size of the respective ICU population was analyzed. Due to similar patient characteristics for all ten definitions, we selected three indicator definitions to additionally test statistically against IQM. Results: We analyzed a total of 5,980,702 completed hospital cases, out of which 913,402 referred to an ICU criterion (14.7% of all cases). A key finding is the significant variability in ICU population size, depending on definitions. The most restrictive definition of only mechanical ventilation (DOV definition) resulted in 111,966 (1.9%) cases; mechanical ventilation plus typical intensive care procedure codes (IQM definition) resulted in 210,147 (3.5%) cases; defining each single bed individually as ICU or IMC (ICUá´§IMC definition) resulted in 411,681 (6.9%) cases; and defining any coded length of stay at ICU (LOSi definition) resulted in 721,293 (12.1%) cases. Further testing results for indicator definitions are reported. Conclusions: The size of the population, utilization rates, outcomes, and capacity assumptions clearly depend on the definition of ICU. Therefore, the underlying ICU definition should be stated when making any comparisons. From previous studies, we anticipated that 25-30% of all ICU patients should be mechanically ventilated, and therefore, we conclude that the ICUá´§IMC definition is the most plausible approximation. We suggest a mandatory application of a clearly defined ICU term for all hospitals nationwide for improved benchmarking and data analysis.

Sonographic Evaluation of Gastric Residual Volume during Enteral Nutrition in Critically Ill Patients Using a Miniaturized Ultrasound Device.

BACKGROUND: To assess the risk of aspiration, nutrient tolerance, and gastric emptying of patients in ICUs, gastric ultrasound can provide information about the gastric contents. Using established formulas, the gastric residual volume (GRV) can be calculated in a standardized way by measuring the gastric antrum. The purpose of this study was to determine the GRV in a cohort of enterally fed patients using a miniaturized ultrasound device to achieve knowledge about feasibility and the GRV over time during the ICU stay. The findings could contribute to the optimization of enteral nutrition (EN) therapy. METHODS: A total of 217 ultrasound examinations with 3 measurements each (651 measurements in total) were performed twice daily (morning and evening) in a longitudinal observational study on 18 patients with EN in the interdisciplinary surgical ICU of Saarland University Medical Center. The measured values of the GRV were analyzed in relation to the clinical course, the nutrition, and other parameters. RESULTS: Measurements could be performed without interrupting the flow of clinical care and without pausing EN. The GRV was significantly larger with sparsely auscultated bowel sounds than with normal and excited bowel sounds (p < 0.01). Furthermore, a significantly larger GRV was present when using a high-caloric/low-protein nutritional product compared to an isocaloric product (p = 0.02). The GRV at the morning and evening measurements showed no circadian rhythm. When comparing the first and last ultrasound examination of each patient, there was a tendency towards an increased GRV (p = 0.07). CONCLUSION: The GRV measured by miniaturized ultrasound devices can provide important information about ICU patients without restricting treatment procedures in the ICU. Measurements are possible while EN therapy is ongoing. Further studies are needed to establish gastric ultrasound as a management tool in nutrition therapy.

[Mortality in sepsis and septic shock in Germany. Results of a systematic review and meta-analysis]. / Sterblichkeit bei Sepsis und septischem Schock in Deutschland. Ergebnisse eines systematischen Reviews mit Metaanalyse.

BACKGROUND: The reported mortality for sepsis and septic shock varies between 15% and 59% in international comparison. For Germany, the number of studies is limited. Previous estimations of mortality in Germany are outdated or based on claims data analyses. Various authors discuss whether lacking quality initiatives and treatment standards in Germany could cause higher mortality for sepsis. This contrasts with the internationally well-recognized performance of the German intensive care infrastructure during the COVID-19 pandemic. OBJECTIVES: The objectives of this systematic review and meta-analysis were to estimate 30-day and 90-day mortality of patients with sepsis and patients with septic shock in Germany and to compare the mortality with that of other industrialized regions (Europe, North America). MATERIAL AND METHODS: A systematic literature search included interventional and observational studies published between 2009 and 2020 in PubMed and the Cochrane Library that analyzed adult patients with sepsis, severe sepsis and septic shock in Europe and North America. Studies with less than 20 patients were excluded. The 30-day and 90-day mortality for sepsis and septic shock were pooled separately for studies conducted in Germany, Europe (excluding Germany) and North America in a meta-analysis using a random effects model. Mortality over time was analyzed in a linear regression model. RESULTS: Overall, 134 studies were included. Of these, 15 studies were identified for the estimation of mortality in Germany, covering 10,434 patients, the number of patients per study ranged from 28 to 4183 patients. The 30-day mortality for sepsis was 26.50% (95% confidence interval, CI: 19.86-33.15%) in Germany, 23.85% (95% CI: 20.49-27.21%) in Europe (excluding Germany) and 19.58% (95% CI: 14.03-25.14%) in North America. The 30-day mortality for septic shock was 30.48% (95% CI: 29.30-31.67%) in Germany, 34.57% (95% CI: 33.51-35.64%) in Europe (excluding Germany) and 33.69% (95% CI: 31.51-35.86%) in North America. The 90-day mortality for septic shock was 38.78% (95% CI: 32.70-44.86%) in Germany, 41.90% (95% CI: 38.88-44.91%) in Europe (excluding Germany) and 34.41% (95% CI: 25.66-43.16%) in North America. A comparable decreasing trend in sepsis 30-day mortality was observed in all considered regions since 2009. CONCLUSION: Our analysis does not support the notion that mortality related to sepsis and septic shock in Germany is higher in international comparison. A higher mortality would not be obvious either, since intensive care, for example also during the COVID-19 pandemic, is regarded as exemplary in Germany and the structural quality, such as the number of intensive care beds per 100,000 inhabitants, is high in international comparison. Nevertheless, deficits could also exist outside intensive care medicine. A comparison of international individual studies should take greater account of the structure of healthcare systems, the severity of disease and the limitations resulting from the data sources used.

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.

Image quality to estimate ventricular ejection fraction by last year medical students improves after short courses of training.

BACKGROUND: Transthoracic echocardiography is the primary imaging modality for diagnosing cardiac conditions but medical education in this field is limited. We tested the hypothesis that a structured theoretical and supervised practical course of training in focused echocardiography in last year medical students results in a more accurate assessment and more precise calculation of left ventricular ejection fraction after ten patient examinations. METHODS: After a theoretical introduction course 25 last year medical students performed ten transthoracic echocardiographic examination blocks in postsurgical patients. Left ventricular function was evaluated both with an eye-balling method and with the calculated ejection fraction using diameter and area of left ventricles. Each examination block was controlled by a certified and blinded tutor. Bias and precision of measurements were assessed with Bland and Altman method. RESULTS: Using the eye-balling method students agreed with the tutor's findings both at the beginning (88%) but more at the end of the course (95.7%). The variation between student and tutor for calculation of area, diameter and ejection fraction, respectively, was significantly lower in examination block 10 than in examination block 1 (each p < 0.001). Students underestimated both the length and the area of the left ventricle at the outset, as complete imaging of the left heart in the ultrasound sector was initially unsuccessful. CONCLUSIONS: A structured theoretical and practical transthoracic echocardiography course of training for last year medical students provides a clear and measurable learning experience in assessing and measuring left ventricular function. At least 14 examination blocks are necessary to achieve 90% agreement of correct determination of the ejection fraction.

Volatile Organic Compounds in Patients With Acute Kidney Injury and Changes During Dialysis.

OBJECTIVES: To characterize volatile organic compounds in breath exhaled by ventilated care patients with acute kidney injury and changes over time during dialysis. DESIGN: Prospective observational feasibility study. SETTING: Critically ill patients on an ICU in a University Hospital, Germany. PATIENTS: Twenty sedated, intubated, and mechanically ventilated patients with acute kidney injury and indication for dialysis. INTERVENTIONS: Patients exhalome was evaluated from at least 30 minutes before to 7 hours after beginning of continuous venovenous hemodialysis. MEASUREMENTS AND MAIN RESULTS: Expired air samples were aspirated from the breathing circuit at 20-minute intervals and analyzed using multicapillary column ion-mobility spectrometry. Volatile organic compound intensities were compared with a ventilated control group with normal renal function. A total of 60 different signals were detected by multicapillary column ion-mobility spectrometry, of which 44 could be identified. Thirty-four volatiles decreased during hemodialysis, whereas 26 remained unaffected. Forty-five signals showed significant higher intensities in patients with acute kidney injury compared with control patients with normal renal function. Among these, 30 decreased significantly during hemodialysis. Volatile cyclohexanol (23 mV; 2575th, 19-38), 3-hydroxy-2-butanone (16 mV, 9-26), 3-methylbutanal (20 mV; 14-26), and dimer of isoprene (26 mV; 18-32) showed significant higher intensities in acute kidney impairment compared with control group (12 mV; 10-16 and 8 mV; 7-14 and not detectable and 4 mV; 0-6; p < 0.05) and a significant decline after 7 hours of continuous venovenous hemodialysis (16 mV; 13-21 and 7 mV; 6-13 and 9 mV; 8-13 and 14 mV; 10-19). CONCLUSIONS: Exhaled concentrations of 45 volatile organic compounds were greater in critically ill patients with acute kidney injury than in patients with normal renal function. Concentrations of two-thirds progressively decreased during dialysis. Exhalome analysis may help quantify the severity of acute kidney injury and to gauge the efficacy of dialysis.

Presepsin and Inflammatory Markers Correlate With Occurrence and Severity of Nonocclusive Mesenteric Ischemia After Cardiovascular Surgery.

OBJECTIVES: To prospectively evaluate the relationship of established inflammatory markers and presepsin on nonocclusive mesenteric ischemia and to correlate presepsin levels to the occurrence and severity of nonocclusive mesenteric ischemia. DESIGN: Patients were prospectively enrolled and blood samples taken, followed by a retrospective evaluation of laboratory values and angiographic findings. The study was ethics committee approved. SETTINGS: Patients with clinical suspicion of nonocclusive mesenteric ischemia underwent catheter angiography of the superior mesenteric artery. Images were assessed by two experienced radiologists on consensus basis using a previously published standardized reporting system (Homburg-Nonocclusive Mesenteric Ischemia-Score). Two groups were formed according to the severity of nonocclusive mesenteric ischemia, mild and severe, patients without clinical signs of nonocclusive mesenteric ischemia formed the reference group. These data were correlated to inflammatory blood markers assessed pre- and postoperatively: C-reactive protein, leucocytes, procalcitonin, and presepsin as well as outcome data. PATIENTS: Between January 2010 and March 2011, a total of 839 patients undergoing cardiovascular surgery participated in this study. MEASUREMENTS AND MAIN RESULTS: Mild nonocclusive mesenteric ischemia was diagnosed in 4.5%, and severe nonocclusive mesenteric ischemia in 3.2%. Median postoperative presepsin concentrations were significantly greater in mild and severe nonocclusive mesenteric ischemia than in non-nonocclusive mesenteric ischemia. Statistics showed that postoperative presepsin better discriminated mild and severe nonocclusive mesenteric ischemia than any other tested biomarker. CONCLUSIONS: Elevated postoperative plasma presepsin concentrations are an independent predictor of mild and severe nonocclusive mesenteric ischemia. The established inflammatory blood markers significantly correlate with the development and severity of nonocclusive mesenteric ischemia.

Presepsin (sCD14-ST) Is a Novel Marker for Risk Stratification in Cardiac Surgery Patients.

BACKGROUND: Presepsin (soluble cluster-of-differentiation 14 subtype [sCD14-ST]) is a humoral risk stratification marker for systemic inflammatory response syndrome and sepsis. It remains unknown whether presepsin can be used to stratify risk in elective cardiac surgery. The authors therefore determined the usefulness of presepsin for risk stratification in patients having elective cardiac surgery. METHODS: Eight hundred fifty-six cardiac surgical patients were prospectively studied. Preoperative plasma concentrations of presepsin, procalcitonin, N-terminal pro-hormone natriuretic peptide, cystatin C, and the additive European System of Cardiac Operative Risk Evaluation 2 were compared to mortality at 30 days (primary outcome), 6 months, and 2 yr. Discrimination was assessed with C statistic. Logistic regression analysis was used to calculate univariable and multivariable odds ratios. RESULTS: Thirty-day mortality was 3.2%, 6-month mortality was 6.1%, and 2-yr mortality was 10.4% across the population. Median preoperative presepsin concentrations were significantly greater in 30-day nonsurvivors than in survivors: 842 pg/ml (interquartile range, 306 to 1,246) versus 160 pg/ml (interquartile range, 122 to 234); difference, 167 pg/ml (interquartile range, 92 to 301; P < 0.001). The results were similar for 6-month and 2-yr mortality. Compared to the European System of Cardiac Operative Risk Evaluation 2, presepsin concentration provided better discrimination for postoperative mortality at all follow-up periods, including 30 days (C statistic 0.88 vs. 0.74), 6 months (0.87 vs. 0.76), and 2 yr (0.81 vs. 0.74). Presepsin also provided better discrimination than cystatin C, N-terminal pro-hormone natriuretic peptide, or procalcitonin. Elevated presepsin remained an independent risk predictor after adjustment for potential confounding factors. CONCLUSIONS: Elevated preoperative plasma presepsin concentration is an independent predictor of postoperative mortality in elective cardiac surgery patients and is a stronger predictor than several other commonly used assessments.

Prevalence, Diagnosis, Perioperative Monitoring and Treatment of Right Ventricular Dysfunction and/or Pulmonary Arterial Hypertension in Cardiac Surgical Patients in Germany-A Postal Survey.

Background Sparse data are available on the prevalence of right ventricular dysfunction and/or pulmonary arterial hypertension in patients scheduled for cardiac surgery in Germany as well as on the intensity and modalities used for diagnosis, perioperative monitoring, and treatment of these comorbidities. Methods A postal survey including questions on the prevalence of preoperative right ventricular dysfunction and/or pulmonary arterial hypertension in patients undergoing cardiac surgery in 2009 was sent to 81 German heart centers. Total 47 of 81 (58%) heart centers returned the questionnaires. The centers reported data on 51,095 patients, and 49.8% of the procedures were isolated coronary artery bypass grafting. Results Data on the prevalence of preoperative pulmonary hypertension and/or right ventricular dysfunction were not available in 54% and 64.6% of centers. In the remaining hospitals, 19.5% of patients presented right heart dysfunction and 10% pulmonary arterial hypertension. Preoperative echocardiography was performed in only 45.3% of the coronary artery bypass grafting cases. Preoperative pharmacologic treatment of pulmonary hypertension or right ventricular dysfunction with oral sildenafil, inhaled prostanoids, or nitric oxide was initiated in 71% and 95.7% of the centers, respectively. Intra- and postoperative treatment was most frequently accomplished with phosphodiesterase-III inhibitors. Conclusion The prevalence of preoperative right heart dysfunction and pulmonary arterial hypertension in cardiac surgical patients in Germany seems to be substantial. However, in more than 50% of the patients, no preoperative data on right ventricular function and pulmonary arterial pressure are available. This may lead to underestimation of perioperative risk and inappropriate management of this high-risk population.

Prognostic value of procalcitonin in patients after elective cardiac surgery: a prospective cohort study.

BACKGROUND: Procalcitonin (PCT) is a well-known prognostic marker after elective cardiac surgery. However, the impact of elevated PCT in patients with an initially uneventful postoperative course is still unclear. The aim of this study was to evaluate PCT levels as a prognostic tool for delayed complications after elective cardiac surgery. METHODS: A prospective study was performed in 751 patients with an apparently uneventful postoperative course within the first 24 h after elective cardiac surgery. Serum PCT concentration was taken the morning after surgery. All patients were screened for the occurrence of delayed complications. Delayed complications were defined by in-hospital death, intensive care unit readmission, or prolonged length of hospital stay (>12 days). Odds ratios (OR) [with 95% confidence interval (CI)] were calculated by logistic regression analyses and adjusted for confounders. Predictive capacity of PCT for delayed complications was calculated by ROC analyses. The cutoff value of PCT was derived from the Youden Index calculation. RESULTS: Among 751 patients with an initially uneventful postoperative course, 117 patients developed delayed complications. Serum PCT levels the first postoperative day were significantly higher in these 117 patients (8.9 ng/ml) compared to the remaining 634 (0.9 ng/ml; p < 0.001). ROC analyses showed that PCT had a high accuracy to predict delayed complications (optimal cutoff value of 2.95 ng/ml, AUC of 0.90, sensitivity 73% and specificity 97%). Patients with PCT levels above 2.95 ng/ml the first postoperative day had a highly increased risk of delayed complications (adjusted OR, 110.2; 95% CI 51.5-235.5; p < 0.001). CONCLUSIONS: A single measurement of PCT seems to be a useful tool to identify patients at risk of delayed complications despite an initially uneventful postoperative course.

[S3-Guideline: Recommendations for intra-aortic balloon pumping in cardiac surgery]. / S3-Leitlinie "Einsatz der intraaortalen Ballongegenpulsation in der Herzchirurgie".

Although intra-aortic balloon pumping (IABP) is the most frequently used mechanical cardiac assist device in cardiothoracic surgery, there are only guidelines for substantive sections of aortic counterpulsation including prophylactic and postoperative use. In contrast, evidence-based recommendations are still lacking concerning intraoperative use, management, contraindication and other relevant issues. According to international surveys, important aspects of IABP usage show a wide variation in clinical practice. The results of a national questionnaire performed before initiation of this guideline confirmed these findings and demonstrated a clear need for the development of a consensus-based guideline. Therefore, the presented multidisciplinary S-3-guideline was developed under the direction of the German Society for Thoracic and Cardiovascular Surgery (Deutsche Gesellschaft für Thorax-, Herz- und Gefäßchirurgie, DGTHG) to make evidence-based recommendations for the usage of aortic counterpulsation after cardiothoracic surgery according to the requirements of the Association of the Scientific Medical Societies in Germany (AWMF) and the Medical Centre for Quality (Ärztliches Zentrum für Qualität - (ÄZQ)). Main topics discussed in this guideline involve IABP support in the prophylactic, preoperative, intraoperative and postoperative setting as well as the treatment of right heart failure, contraindications, anticoagulation, monitoring, weaning, and limitations of IABP therapy. The presented 15 key messages of the guideline were approved after two consensus meetings under moderation of the AWMF with participation of the German Society of Cardiology (DGK), German Society of Anaesthesiology and Intensive Care Medicine (DGAI), German Interdisciplinary Association for Intensive Care (DIVI) and the German Society for Cardiovascular Engineering (DGfK).

[Echocardiography - hemodynamically focused echocardiography]. / Echokardiografie - Hämodynamisch fokussierte Echokardiografie.

Based on the previously published international evidence-based recommendations for focused cardiac ultrasound, aim of this paper is to provide a possible approach to the complementary application of TTE and TOE in hemodynamically unstable patients. Thereby the cardiac ultrasound examination is centered on the search of an answer or solution to a clinically relevant question or problem and does not replace an all-encompassing examination performed by cardiologists.

Risk factors for nonocclusive mesenteric ischemia after elective cardiac surgery.

OBJECTIVE: Nonocclusive mesenteric ischemia (NOMI) may occur after cardiopulmonary bypass. It is crucial to early identify patients who are at risk of developing this complication. The aim of this prospective study was to evaluate perioperative risk factors in a large cohort of patients undergoing elective cardiac surgery. METHODS: From January 1, 2010, to March 31, 2011, all patients scheduled for elective cardiac surgery were screened for participation in this trial. If NOMI was suspected, arterial angiography was performed. NOMI and non-NOMI patients were compared with respect to all variables assessed in this study. Additionally, odds ratios were calculated. Linear discriminant analyses as well as logistic regression analyses were performed to develop a model that identifies patients at risk for developing NOMI. RESULTS: Eight hundred sixty-five patients were included in the study, of whom 78 developed NOMI. Among preoperative parameters, renal insufficiency, diuretic therapy, and age >70 years showed the highest odds ratios for postoperative NOMI. The highest odds ratios for development of NOMI were observed with postoperative variables. In particular, the need for intra-aortic balloon pump support and serum lactate concentrations >5 mmol/L proved to be serious risk factors. Using a linear discriminant analysis with 7 variables, 92.3% of patients were correctly classified (sensitivity 76.9%, specificity 93.8%). CONCLUSIONS: A high index of suspicion for NOMI in patients with the above-mentioned risk factors may decrease the diagnostic and therapeutic delay. To identify at-risk patients the developed risk equation is a useful tool with a high specificity.

Preoperative aortic root geometry and postoperative cusp configuration primarily determine long-term outcome after valve-preserving aortic root repair.

OBJECTIVE: Technical controversies exist in valve-preserving aortic root replacement. We sought to determine predictors of long-term stability of the aortic valve. METHODS: A total of 430 patients (aged 57 ± 15 years, 323 male) underwent valve-preserving aortic root surgery (remodeling in 401, reimplantation in 29) between 1995 and 2009 and were followed echocardiographically. Factors influencing late recurrence of aortic valve regurgitation grade II or greater (n = 45) or need for reoperation on the aortic valve (n = 25) were analyzed. RESULTS: Early mortality was 2.8% (1.9% for elective cases), and actuarial survival at 10 years was 83.5% ± 2.4%. Ten-year freedom from aortic valve regurgitation grade II or greater was 85.0% ± 2.5%. Preoperative aortoventricular junction diameter greater than 28 mm and postoperative effective height of the aortic cusp less than 9 mm were identified as significant predictors for late aortic valve regurgitation grade II or greater in multivariate analysis (both P < .001). Ten-year freedom from reoperation on the aortic valve was 89.3% ± 2.5%. Preoperative aortoventricular junction diameter greater than 28 mm (P < .001), use of pericardial patch (P = .022), and effective height of the aortic cusp less than 9 mm (P = .049) were identified as significant predictors for reoperation in multivariate analysis. Operative technique (remodeling, reimplantation), Marfan syndrome, bicuspid valve anatomy, concomitant central cusp plication, size of prosthesis used, and acute dissection were not associated with an increased risk of late aortic valve regurgitation grade II or greater or reoperation. In patients with preoperative aortoventricular junction diameter greater than 28 mm (n = 94), the addition of central cusp plication significantly improved freedom from aortic valve regurgitation grade II or greater (P = .006) regardless of root procedures (remodeling, P = .011; reimplantation, P = .053). CONCLUSIONS: Long-term stability of valve-preserving aortic root replacement was influenced not by the technique of root repair but by the preoperative aortic root geometry and postoperative cusp configuration.