A new noninvasive finger sensor (NICCI system) for cardiac output monitoring: A method comparison study in patients after cardiac surgery.

BACKGROUND: The new noninvasive finger sensor system NICCI (Getinge; Gothenburg, Sweden) allows continuous cardiac output monitoring. We aimed to investigate its cardiac output measurement performance. OBJECTIVES: To investigate the NICCI system's cardiac output measurement performance. DESIGN: Prospective method comparison study. SETTING: University Medical Center Hamburg-Eppendorf, Hamburg, Germany. PATIENTS: Fifty-one patients after cardiac surgery. MAIN OUTCOME MEASURES: We performed a method comparison study in 51 patients after cardiac surgery to compare NICCI cardiac output (CO NICCI ) and NICCI cardiac output calibrated to pulmonary artery thermodilution cardiac output measurement (CO NICCI-CAL ) with pulmonary artery thermodilution cardiac output (CO PAT ). As a secondary analysis we also compared CNAP cardiac output (CO CNAP ) and externally calibrated CNAP cardiac output (CO CNAP-CAL ) with CO PAT . RESULTS: We analysed 299 cardiac output measurement pairs. The mean of the differences (95% limits of agreement) between CO NICCI and CO PAT was 0.6 (-1.8 to 3.1) l min -1 with a percentage error of 48%. The mean of the differences between CO NICCI-CAL and CO PAT was -0.4 (-1.9 to 1.1) l min -1 with a percentage error of 29%. The mean of the differences between CO CNAP and CO PAT was 1.0 (-1.8 to 3.8) l min -1 with a percentage error of 53%. The mean of the differences between CO CNAP-CAL and CO PAT was -0.2 (-2.0 to 1.6) l min -1 with a percentage error of 35%. CONCLUSION: The agreement between CO NICCI and CO PAT is not clinically acceptable. TRIAL REGISTRATION: The study was registered in the German Clinical Trial Register (DRKS00023189) after inclusion of the first patient on October 2, 2020.

Blunt traumatic right coronary artery dissection presenting with second-degree atrioventricular block and late-onset severe cardiogenic shock.

BACKGROUND: Blunt chest injury may induce several cardiovascular traumata, requiring immediate care. Right coronary artery dissection (RCA) is an extremely rare sequela in this setting and is associated with high mortality, if it remains undiagnosed. Case presentation We present the case of an RCA dissection after blunt chest trauma in a 16-year-old patient, who initially presented with a second-degree atrioventricular block as solitary manifestation on admission. Typical electrocardiographic findings, such as ST segmental changes or pathological Q waves were absent. Serial echocardiograms excluded segmental motion abnormalities, pericardial effusion or right ventricular strain. Nevertheless, a complementary computed tomography coronary angiography revealed this potentially lethal condition several hours later. The patient underwent an emergency surgical myocardial revascularization under the circulatory support of veno-arterial extracorporeal membrane oxygenation and suffered a prolonged right ventricular insufficiency with severe late-onset cardiogenic shock, due to an extensive myocardial infarction of the inferoseptal ventricular wall. CONCLUSION: Right coronary artery dissection after high-speed blunt chest injury constitutes a diagnostic challenge, especially in the absence of typical electrocardiographic and echocardiographic findings in young patients. This condition may dramatically deteriorate in time, leading to severe cardiogenic shock and life-threatening arrhythmias.

Feasibility, safety, and resource utilisation of active mobilisation of patients on extracorporeal life support: a prospective observational study.

BACKGROUND: There is scarce evidence on the feasibility, safety and resource utilisation of active mobilisation in critically ill patients on extracorporeal life support (ECLS). METHODS: This prospective observational single-centre study included all consecutive critically ill patients on ECLS admitted to an academic centre in Germany over a time period of one year. The level of mobilisation was categorised according to the ICU Mobility Scale (IMS). Primary outcome was complications during mobilisation. RESULTS: During the study period, active mobilisation with an activity level on the IMS of ≥ 3 was performed at least on one occasion in 43 out of 115 patients (37.4%). A total of 332 mobilisations with IMS ≥ 3 were performed during 1242 ECLS days (26.7%). ECLS configurations applied were va-ECMO (n = 63), vv-ECMO (n = 26), vv-ECCO2R (n = 12), av-ECCO2R (n = 10), and RVAD (n = 4). Femoral cannulation had been in place in 108 patients (93.9%). The median duration of all mobilisation activities with IMS ≥ 3 was 130 min (IQR 44-215). All mobilisations were undertaken by a multi-professional ECLS team with a median number of 3 team members involved (IQR 3-4). Bleeding from cannulation site requiring transfusion and/or surgery occurred in 6.9% of actively mobilised patients and in 15.3% of non-mobilised patients. During one mobilisation episode, accidental femoral cannula displacement occurred with immediate and effective recannulation. Sedation was the major reason for non-mobilisation. CONCLUSIONS: Active mobilisation (IMS ≥ 3) of ECLS patients undertaken by an experienced multi-professional team was feasible, and complications were infrequent and managed successfully. Larger prospective multicentre studies are needed to further evaluate early goal directed sedation and mobilisation bundles in patients on ECLS.

Cardiac output estimation by pulse wave analysis using the pressure recording analytical method and intermittent pulmonary artery thermodilution: A method comparison study after off-pump coronary artery bypass surgery.

BACKGROUND: Invasive pulse wave analysis is used in peri-operative settings to estimate cardiac output (CO). The 'pressure recording analytical method' (PRAM) implemented in the MostCareUp CO monitor is an invasive pulse wave analysis method using high-frequency sampling and analysis of the pulse wave to directly estimate the arterial impedance as a key variable of the proprietary CO estimation algorithm. OBJECTIVE: To compare CO estimated by PRAM (PRAM-CO; test method) with CO measured by pulmonary artery thermodilution (PATD-CO; reference method). DESIGN: Prospective observational method comparison study. PRAM-CO and PATD-CO were assessed simultaneously at five time points with at least 20 min between measurements. Arterial pressure waveforms were carefully checked for damping artefacts and a proprietary electronic filter of the MostCareUp CO monitor was used to optimise waveform quality. SETTING: ICU of a German university hospital from August 2018 until April 2019. PATIENTS: We included adult patients admitted to the ICU after elective off-pump coronary artery bypass surgery who were monitored with a radial arterial catheter and a pulmonary artery catheter. Patients with severe heart valve insufficiency or persistent arrhythmia were excluded. MAIN OUTCOME MEASURES AND ANALYSIS: PATD-CO and PRAM-CO were compared using Bland-Altman analysis accounting for repeated measurements, the percentage error and trending analysis (four-quadrant plot, concordance rate). RESULTS: We analysed 195 paired CO values of 41 patients. Mean PATD-CO and PRAM-CO were 4.99 ±â€Š1.02 and 4.92 ±â€Š1.05 l min, respectively. PATD-CO and PRAM-CO ranged from 3.04 to 8.74 and 2.79 to 8.01 l min, respectively. The mean of the differences between PATD-CO and PRAM-CO was -0.08 ±â€Š0.74 l min with 95% limits of agreement of -1.55 to +1.40 l min. The percentage error was 29.8%. The concordance rate in four-quadrant plot analysis was 92%. CONCLUSION: Using the system's electronic waveform filter PRAM-CO shows good agreement and trending ability compared with PATD-CO in adults after off-pump coronary artery bypass surgery.

Cardiac output estimation by multi-beat analysis of the radial arterial blood pressure waveform versus intermittent pulmonary artery thermodilution: a method comparison study in patients treated in the intensive care unit after off-pump coronary artery bypass surgery.

Cardiac output (CO) is a key hemodynamic variable that can be minimally invasively estimated by pulse wave analysis. Multi-beat analysis is a novel pulse wave analysis method. In this prospective observational clinical method comparison study, we compared CO estimations by multi-beat analysis with CO measured by intermittent pulmonary artery thermodilution (PATD) in adult patients treated in the intensive care unit (ICU) after off-pump coronary artery bypass surgery (OPCAB). We included patients after planned admission to the ICU after elective OPCAB who were monitored with a radial arterial catheter and a pulmonary artery catheter. At seven time points, we determined CO using intermittent PATD (PATD-CO; reference method) and simultaneously recorded the radial arterial blood pressure waveform that we later used to estimate CO using multi-beat analysis (MBA-CO; test method) with the Argos monitor (Retia Medical; Valhalla, NY, USA). Blood pressure waveforms impaired by inappropriate damping properties or artifacts were excluded. We compared PATD-CO and MBA-CO using Bland-Altman analysis accounting for repeated measurements, the percentage error, and the concordance rate derived from four-quadrant plot analysis (15% exclusion zone). We analyzed 167 CO values of 31 patients. Mean PATD-CO was 5.30 ± 1.22 L/min and mean MBA-CO was 5.55 ± 1.82 L/min. The mean of the differences between PATD-CO and MBA-CO was 0.08 ± 1.10 L/min (95% limits of agreement: - 2.13 L/min to + 2.29 L/min). The percentage error was 40.7%. The four-quadrant plot-derived concordance rate was 88%. CO estimation by multi-beat analysis of the radial arterial blood pressure waveform (Argos monitor) shows reasonable agreement compared with CO measured by intermittent PATD in adult patients treated in the ICU after OPCAB.

Increased admission central venous-arterial CO2 difference predicts ICU-mortality in adult cardiac surgery patients.

BACKGROUND: Invasive procedures such as cardiac surgery are associated with perioperative dysfunction of macrocirculation and/or microcirculation and organ failures. Maintenance or resuscitation of an adequate macrocirculation and/or microcirculation is thus crucial in patients after cardiac surgery. We investigated the prognostic power of early central venous-arterial carbon dioxide pressure difference (delta-pCO2) after cardiac surgery. METHODS: Retrospective analysis of data from 1,019 cardiac surgery patients treated in the ICU of a tertiary medical care academic center. Clinical outcomes and laboratory measures including metabolic indices and calculated delta-pCO2 were assessed. Receiver operating characteristic (ROC) curves were generated and sensitivity / specificity analysis was performed. Univariate and multivariate regression models were analyzed. RESULTS: The area under the ROC curve for delta-pCO2 to predict ICU mortality was 0.72 (sensitivity 65% / specificity 76%) with an optimal delta-pCO2 cut-off value of 8.6 mmHg. In multivariate regression, delta-pCO2 was associated with increased ICU mortality (HR 3.72, 95%-CI 1.3-10.66, p = 0.02). After adjustment for typical confounders, delta-pCO2 remained as independent predictor of ICU mortality after cardiac surgery. CONCLUSIONS: In a retrospective data analysis in a large sample of adult post cardiac surgery patients treated in the ICU, we observed that admission central venous-arterial delta-pCO2 independently predicts ICU mortality. Delta-pCO2 might thus contribute risk stratification in ICU patients after cardiac surgery.

Base excess is superior to lactate-levels in prediction of ICU mortality after cardiac surgery.

INTRODUCTION: Cardiac surgery with the use of cardiopulmonary bypass is known to induce distinct metabolic changes. Respective changes in acid-base status including increased systemic lactate levels were previously related to clinical outcomes, but data remain controversial. Therefore, we aim to investigate the relevance of lactate and base excess (BE) levels on ICU-mortality in patients admitted to the ICU after cardiac surgery. MATERIALS AND METHODS: Perioperative data of patients treated in a tertiary care academic center admitted to the ICU after on-pump surgery were analyzed in a retrospective fashion. Receiver operation characteristic (ROC) curves were constructed for admission lactate-levels and BE with calculation of optimal cut-off values to predict ICU mortality. Univariate followed by multivariate regression models were constructed to identify potential outcome-relevant indices. RESULTS: Data from 1,058 patients were included in the analysis. Area under the curves for prediction of ICU mortality were 0.79 for lactate levels at ICU admission (sensitivity 61.9%/ specificity 87.5%; optimal cut-off level 3.9mmol/l), and 0.7 for BE (sensitivity 52.4%/ specificity 93.8%, optimal cut-off level -6.7), respectively. Multivariate regression identified BE < -6.7 as the single metabolic predictor of ICU-mortality (HR 4.78, 95%-CI 1.4-16.33, p = 0.01). Explorative subgroup analyses revealed that the combination of lactate ≤3.9mmol/l and BE ≤ -6.7 has stronger impact on mortality than a combination of lactate of >3.9mmol/l and BE > -6.7 (HR 2.56, 95%-CI 0.18-37.17). CONCLUSIONS: At ICU-admission, severely reduced BE appears superior to hyperlactatemia with regard to prediction of ICU-mortality in patients after cardiac surgery.

A comparison of volume clamp method-based continuous noninvasive cardiac output (CNCO) measurement versus intermittent pulmonary artery thermodilution in postoperative cardiothoracic surgery patients.

The CNAP technology (CNSystems Medizintechnik AG, Graz, Austria) allows continuous noninvasive arterial pressure waveform recording based on the volume clamp method and estimation of cardiac output (CO) by pulse contour analysis. We compared CNAP-derived CO measurements (CNCO) with intermittent invasive CO measurements (pulmonary artery catheter; PAC-CO) in postoperative cardiothoracic surgery patients. In 51 intensive care unit patients after cardiothoracic surgery, we measured PAC-CO (criterion standard) and CNCO at three different time points. We conducted two separate comparative analyses: (1) CNCO auto-calibrated to biometric patient data (CNCObio) versus PAC-CO and (2) CNCO calibrated to the first simultaneously measured PAC-CO value (CNCOcal) versus PAC-CO. The agreement between the two methods was statistically assessed by Bland-Altman analysis and the percentage error. In a subgroup of patients, a passive leg raising maneuver was performed for clinical indications and we present the changes in PAC-CO and CNCO in four-quadrant plots (exclusion zone 0.5 L/min) in order to evaluate the trending ability of CNCO. The mean difference between CNCObio and PAC-CO was +0.5 L/min (standard deviation ± 1.3 L/min; 95% limits of agreement -1.9 to +3.0 L/min). The percentage error was 49%. The concordance rate was 100%. For CNCOcal, the mean difference was -0.3 L/min (±0.5 L/min; -1.2 to +0.7 L/min) with a percentage error of 19%. In this clinical study in cardiothoracic surgery patients, CNCOcal showed good agreement when compared with PAC-CO. For CNCObio, we observed a higher percentage error and good trending ability (concordance rate 100%).

Outcomes of Minimally Invasive Temporary Right Ventricular Assist Device Support for Acute Right Ventricular Failure During Minimally Invasive Left Ventricular Assist Device Implantation.

Right ventricular failure (RVF) may still occur despite the benefits of minimally invasive left ventricular assist device (MI-LVAD) implantation. Our center strategy aims to avoid aggressive postoperative inotrope use by using mechanical support to facilitate right ventricle recovery and adaptation. We herein report first outcomes of patients with minimally invasive temporary right ventricular assist device (MI-t-RVAD) support for RVF during MI-LVAD implantation. Right ventricular failure was defined as requiring more than moderate inotopic support after weaning from cardiopulmonary bypass according to Interagency Registry for Mechanically Assisted Circulatory Support adverse event definitions. All patients requiring MI-t-RVAD support for RVF during MI-LVAD implantation between January, 2012 and April, 2016 were retrospectively reviewed. Clinical endpoints were death or unsuccessful RVAD weaning. Overall 10 patients (90% male, mean age 49.6 ± 14.8 years) underwent MI-t-RVAD implantation. Duration of MI-t-RVAD support was 16.2 ± 11.6 days. Right ventricular assist device weaning and subsequent uneventful awake device explantation was successful in all cases. The 30 day survival was 80%. Our results confirm safety and feasibility of MI-t-RVAD support for acute RVF in the setting of MI-LVAD implantation. The potential benefits of this strategy are more stable hemodynamics in the first postoperative days that usually are crucial for LVAD patients and reduced inotrope requirement.

Percutaneous Dilatation Tracheostomy in Patients with Left Ventricular Assist Device and Established Phenprocoumon Therapy.

Over the last decade, the number of heart transplantations declined, and the number of implanted left ventricular assist devices (LVADs) markedly increased. Accordingly, common intensive care interventions rise and present their own challenges, especially because of the necessary anticoagulation regimen. One of these procedures is percutaneous dilatation tracheostomy (PDT). We herein report our experience with 34 patients with LVAD and established phenprocoumon therapy (International normalized ratio 2.1 ± 0.9, partial thromboplastin time 68.9 ± 19.0 seconds) who underwent PDT between 2006 and 2015 at our specialized cardiac surgery intensive care unit. Intraprocedural success was achieved in all cases (34/34 patients) with sufficient placement of the tracheal tube and adequate mechanical ventilation. No retained secretions or tracheostomy tube obstructions were observed during follow-up. In no case, conversion to surgical tracheostomy was necessary. No serious bleeding complications that required urgent or emergent reoperation occurred during or after the PDT procedure. A total of 16 patients (47.1%) died within the first 30 days after LVAD implantation. This is the first report describing outcomes of patients with LVAD under established phenprocoumon therapy and postoperative implemented PDT. PDT is a safe procedure for those patients. It is not connected with bleeding complications and shows a good procedural outcome.

Preoperative Ticagrelor administration leads to a higher risk of bleeding during and after coronary bypass surgery in a case-matched analysis.

OBJECTIVES: To evaluate the effect of Ticagrelor on intra- and postoperative bleeding complications in patients undergoing coronary bypass surgery. METHODS: For this study, patients who underwent on-pump or off-pump coronary bypass surgery with preoperative acetylsalicylic acid (ASA) and Ticagrelor administration, between January 2014 and December 2014, were included. In the matched control group, continued dual antiplatelet therapy (DAPT) consisted of Clopidogrel and ASA. A total of 28 consecutive patients (24 males; 73 ± 6.6 years) with preoperative Ticagrelor intake underwent elective (n = 22), urgent (n = 2) or emergency (n = 4) cardiac bypass surgery. The postoperative blood loss, red blood cell units given and intra- and postoperative bleeding complications were documented. To evaluate the effect of Ticagrelor treatment on bleeding during and after coronary bypass surgery in a non-randomized study, we used a case-matched analysis. RESULTS: Baseline parameters showed no important differences between the study group and the control group regarding the matching variables, left ventricular function, preoperative clinical status and risk stratification. The preoperative laboratory analysis showed no important differences regarding coagulation and blood cell count parameters. Overall blood loss was significantly higher in the study group with a mean loss of 1028.8 ± 735.5 ml (P = 0.0002). Accordingly, units of red blood cells administered were also significantly higher in the study group (P = 0.0002). In the Ticagrelor group, there were six rethoracotomies due to postoperative bleeding with a blood loss of more than 1200 ml in the first 3 h. With no rethoracotomies in the Clopidogrel group, this also showed statistical significance for the postoperative course (P = 0.02). There were no differences found regarding ICU stay and ventilation time. Comparing the mean hospital stay, the study group presented a significantly longer stay than the control group (P = 0.001). CONCLUSIONS: Recent studies about bleeding complications in patients with Ticagrelor intake undergoing CABG in a real-life scenario presented inconsistent data. We were able to show in a case-matched analysis that Ticagrelor administration leads to significantly higher blood loss, more red blood cell units transfused and a higher rate of rethoracotomies. The data also present a longer hospital stay to the disadvantage of the study group. Consequently, Ticagrelor intake before CABG procedures should be avoided or at least discontinued 3 days before cardiac surgery.

Radial Artery Applanation Tonometry for Continuous Noninvasive Cardiac Output Measurement: A Comparison With Intermittent Pulmonary Artery Thermodilution in Patients After Cardiothoracic Surgery.

OBJECTIVES: Radial artery applanation tonometry allows completely noninvasive continuous cardiac output estimation. The aim of the present study was to compare cardiac output measurements obtained with applanation tonometry (AT-CO) using the T-Line system (Tensys Medical, San Diego, CA) with cardiac output measured by intermittent pulmonary artery thermodilution using a pulmonary artery catheter (PAC-CO) with regard to accuracy, precision of agreement, and trending ability. DESIGN: A prospective method comparison study. SETTING: The study was conducted in a cardiosurgical ICU of a German university hospital. PATIENTS: We performed cardiac output measurements in 50 patients after cardiothoracic surgery. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Three independent sets of three consecutive thermodilution measurements (i.e., PAC-CO) each were performed per patient, and AT-CO was measured simultaneously. The average of the three thermodilution cardiac output measurements was compared with the average of the corresponding three AT-CO values resulting in 150 paired cardiac output measurements. In 13 patients, cardiac output-modifying maneuvers performed for clinical reasons additionally allowed to evaluate trending ability. For statistical analysis, we used Bland-Altman analysis, the percentage error, four-quadrant plot, and concordance analysis. Mean PAC-CO was 4.7 ± 1.2 L/min and mean AT-CO was 4.9 ± 1.1 L/min. The mean of differences was -0.2 L/min with 95% limits of agreement of -1.8 to + 1.4 L/min. The percentage error was 34%. The concordance rate was 95%. CONCLUSIONS: Continuous cardiac output measurement using the noninvasive applanation tonometry technology is basically feasible in ICU patients after cardiothoracic surgery. The applanation tonometry technology provides cardiac output values with reasonable accuracy and precision of agreement compared with intermittent pulmonary artery thermodilution measurements in a clinical study setting and is able to reliably track cardiac output changes induced by cardiac output-modifying maneuvers.

Efficacy of prophylactic intra-aortic balloon pump therapy in chronic heart failure patients undergoing cardiac surgery.

This study investigated the efficacy of prophylactic intraoperative intra-aortic balloon pump (IABP) usage in chronic heart failure patients with severely reduced left ventricular function undergoing elective cardiac surgery. Between January 2008 and December 2012, 107 patients with severely reduced left ventricular ejection fraction (LVEF <35%) received prophylactic intraoperative IABP implantation during open-heart surgery. Surgical procedures performed were isolated coronary artery bypass grafting (CABG) in 35 patients (32.7%), aortic valve replacement in 12 (11.2%), mitral valve repair or replacement in 15 (14.0%), combined valve and CABG procedures in 27 (25.2%), and other surgical procedures in 18 (16.8%). Results and outcomes were compared with those in a propensity score-matched cohort of 107 patients who underwent cardiac surgery without intraoperative IABP implantation. Matching criteria were age, gender, LVEF, and surgical procedure. Duration of intensive care unit (ICU) stay, duration of hospital stay, and 30-day mortality were markers of outcome. In the IABP group, mean patient age was 69.1 ± 13.7 years; 66.4% (70) were male. All IABPs were placed intraoperatively. Mean duration of IABP application time was 42.4 ± 8.7 h. IABP-related complications occurred in five patients (4.7%), including one case of inguinal bleeding, one case of mesenteric ischemia, and ischemia of the lower limb in three patients. No stroke or major bleeding occurred during IABP support. Mean durations of ICU and hospital stay were 3.38 ± 2.15 days and 7.69 ± 2.02 days, respectively, in the IABP group, and 4.20 ± 3.14 days and 8.57 ± 3.26 days in the control group, showing statistically significant reductions in duration of ICU and hospital stay in the IABP group (ICU stay, P = 0.036; hospital stay, P = 0.015). Thirty-day survival rates were 92.5 and 94.4% in the IABP and control group, respectively, showing no statistically significant difference (P = 0.75). IABP usage in chronic heart failure patients with severely reduced LVEF undergoing cardiac surgery was safe and resulted in shorter ICU and hospital stay but did not influence 7- and 30-day survival rates.

Isolated permanent right ventricular assistance using the HVAD continuous-flow pump.

Acute isolated right ventricular (RV) failure from myocardial infarction is a rare scenario. To date, there are no assist devices developed or approved for permanent isolated right heart support. We report on the successful implantation of a HeartWare HVAD as an isolated RV assist in a patient who suffered extended RV myocardial infarction after iatrogenic dissection of the right coronary artery. No manipulations of the system were required to adapt the assist device to the pulmonary circulation.

First successful use of the new ab5000 portable circulatory support console as bridge to recovery in a case of dilated cardiomyopathy.

INTRODUCTION: Growing clinical experience and improved technology have led to more widespread use of ventricular assist devices in patients with end-stage heart failure. METHODS: We report the case of a patient with preexisting cardiomyopathy who arrived at our center in cardiogenic shock and received a biventricular assist device. RESULTS: The new compact Abiomed Portable Circulatory Support Console facilitated mobilization of the patient which was particularly advantageous in the face of transient hemiparesis. After recovery from cardiogenic shock, device removal was performed following a bridge-to-recovery concept. He was discharged in a state of full cardiac recompensation and is back to everyday life with stable cardiac function up to 24 months after the incident. CONCLUSIONS: This is the first report describing successful clinical use of the AB5000 assist device in combination with the portable console. Furthermore, it underlines the potential of temporary circulatory support to induce permanent myocardial recovery even in cases of preexisting cardiomyopathy.