Identifying High-Risk Patients for Severe Pulmonary Complications after Cardiosurgical Procedures as a Target Group for Further Assessment of Lung-Protective Strategies.

OBJECTIVES: It remains unclear whether intraoperative lung-protective strategies can reduce the rate of respiratory complications after cardiac surgery, partly because low-risk patients have been studied in the past. The authors established a screening model to easily identify a high-risk group for severe pulmonary complications (ie, pneumonia or acute respiratory distress syndrome) that may be the ideal target population for the assessment of the potential benefits of such measures. DESIGN: Retrospective observational trial. SETTING: Departments of cardiac surgery and cardiac anesthesia of a university hospital. PARTICIPANTS: Consecutive patients undergoing cardiac surgery on cardiopulmonary bypass and subsequent treatment at a dedicated cardiosurgical intensive care unit between January 2019 and March 2021. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of the 2,572 patients undergoing surgery, 84 (3.3%) developed pneumonia/acute respiratory distress syndrome that significantly affected the outcome (ie, longer ventilatory support [66% vs 11%], higher reintubation rate [39% vs 3%]), prolonged length of intensive care unit [33 ± 36 vs 4 ± 10 days] and hospital stay [10 ± 15 vs 6 ± 7 days], and higher in-hospital [43% vs 9%] as well as 30-day [7% vs 3%] mortality). The screening model for severe pulmonary complications included left ventricular ejection fraction <52%, EuroSCORE II (European System for Cardiac Operative Risk Evaluation II) >5.9, cardiopulmonary bypass time >123 minutes, left ventricular assist device or aortic repair surgery, and bronchodilatory therapy. A cutoff for the predicted risk of 2.5% showed optimal sensitivity and specificity, with an area under the receiver operating characteristic curve of 0.82. CONCLUSIONS: The authors suggest that future research on intraoperative lung-protective measures focuses on this high-risk population, primarily aiming to mitigate severe forms of postoperative pulmonary dysfunction associated with poor outcomes and increased resource consumption.

Stroke Volume and Arterial Pressure Fluid Responsiveness in Patients With Elevated Stroke Volume Variation Undergoing Major Vascular Surgery: A Prospective Intervention Study.

OBJECTIVES: The identification of potential hemodynamic indicators to increase the predictive power of stroke-volume variation (SVV) for mean arterial pressure (MAP) and stroke volume (SV) fluid responsiveness. DESIGN: A prospective intervention study. SETTING: At a single-center university hospital. PARTICIPANTS: Nineteen patients during major vascular surgery with 125 fluid interventions. INTERVENTIONS: When SVV ≥13% occurred for >30 seconds, 250 mL of Ringer's lactate were given within 2 minutes. MEASUREMENTS AND MAIN RESULTS: Hemodynamic variables, such as pulse-pressure variation (PPV) and dynamic arterial elastance (Edyn), were measured by pulse power-wave analysis. The outcomes were MAP and SV responsiveness, defined as an increase of at least 10% of MAP and SV within 5 minutes of the fluid intervention. Of the fluid interventions, 48% were MAP-responsive, and 66% were SV-responsive. The addition of PPV and Edyn cut-off values to the SVV cut-off decreased sensitivity from 1-to-0.66 to-0.82, and concomitantly increased specificity from 0-to- 0.65-to-0.93 for the prediction of MAP and SV responsiveness in the authors' study setting. The areas under the receiver operating characteristic curves of PPV and Edyn for the prediction of MAP responsiveness were 0.79 and 0.75, respectively. The areas under the receiver operating characteristic curves for PPV and Edyn to predict SV responsiveness were 0.85 and 0.77, respectively. CONCLUSIONS: The PPV and Edyn showed good accuracy for the prediction of MAP and SV responsiveness in patients with elevated SVV during vascular surgery. Either PPV or Edyn may be used in conjunction with SVV to better predict MAP and SV fluid responsiveness in patients undergoing vascular surgery.

Administration of vitamin D and its metabolites in critically ill adult patients: an updated systematic review with meta-analysis of randomized controlled trials.

BACKGROUND: The clinical significance of vitamin D administration in critically ill patients remains inconclusive. The purpose of this systematic review with meta-analysis was to investigate the effect of vitamin D and its metabolites on major clinical outcomes in critically ill patients, including a subgroup analysis based on vitamin D status and route of vitamin D administration. METHODS: Major databases were searched through February 9, 2022. Randomized controlled trials of adult critically ill patients with an intervention group receiving vitamin D or its metabolites were included. Random-effect meta-analyses were performed to estimate the pooled risk ratio (dichotomized outcomes) or mean difference (continuous outcomes). Risk of bias assessment included the Cochrane tool for assessing risk of bias in randomized trials. RESULTS: Sixteen randomized clinical trials with 2449 patients were included. Vitamin D administration was associated with lower overall mortality (16 studies: risk ratio 0.78, 95% confidence interval 0.62-0.97, p = 0.03; I2 = 30%), reduced intensive care unit length of stay (12 studies: mean difference - 3.13 days, 95% CI - 5.36 to - 0.89, n = 1250, p = 0.006; I2 = 70%), and shorter duration of mechanical ventilation (9 studies: mean difference - 5.07 days, 95% CI - 7.42 to - 2.73, n = 572, p < 0.0001; I2 = 54%). Parenteral administration was associated with a greater effect on overall mortality than enteral administration (test of subgroup differences, p = 0.04), whereas studies of parenteral subgroups had lower quality. There were no subgroup differences based on baseline vitamin D levels. CONCLUSIONS: Vitamin D supplementation in critically ill patients may reduce mortality. Parenteral administration might be associated with a greater impact on mortality. Heterogeneity and assessed certainty among the studies limits the generalizability of the results. TRIAL REGISTRATION: PROSPERO international prospective database of systematic reviews (CRD42021256939-05 July 2021).

Intraoperative Off-Label Reversal of Apixaban by Andexanet Alfa while on VA-ECMO Immediately After Emergent Surgery for Acute Type A Aortic Dissection.

The authors report a case of intraoperative reversal of apixaban with andexanet alfa in a patient supported with venoarterial extracorporeal membrane oxygenation due to low- cardiac-output immediately after surgery for acute type A aortic dissection and massive intraoperative transfusion with administration of procoagulants. In this patient, andexanet alfa's off-label use was not associated with acute thrombotic complications despite being given during extracorporeal life support and after previous administration of prothrombin complex concentrates.

Initial Postoperative Hemoglobin Values Are Independently Associated With One-Year Mortality in Patients Undergoing Double-Lung Transplantation Requiring Intraoperative Transfusion.

OBJECTIVE: To evaluate the association of postoperative hemoglobin values and mortality in patients undergoing double- lung transplantation with intraoperative transfusion. DESIGN: Retrospective cohort study. SETTING: University hospital. PARTICIPANTS: Adult patients who underwent double-lung transplantation at the authors' institution, with intraoperative transfusion of packed red blood cells between 2009 and 2015. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Intraoperative transfusion requirements and general characteristics of 554 patients were collected. A generalized additive model, controlling for postoperative hemoglobin levels, number of transfused units of packed red blood cells, perioperative change in hemoglobin levels, disease leading to lung transplantation, and postoperative extracorporeal membrane oxygenation, was created to predict one-year mortality. A postoperative hemoglobin level of 11.3 g/dL was calculated as an optimal cutoff point. The patients were stratified according to this level. The end -point was all-cause one-year mortality after double-lung transplantation, assessed using the Kaplan-Meier analysis with log-rank test. All-cause mortality of the 554 patients was 17%. Postoperatively, 171 patients (31%) were categorized as being below the cutoff point. Improved survival was observed in the group with higher postoperative hemoglobin values (p = 0.002). CONCLUSION: Lower postoperative hemoglobin levels in double-lung transplantation recipients were associated with increased mortality during the first year after surgery. Confirmation of these findings in additional investigations could alter patient blood management for double-lung transplantation.

Cefuroxime plasma and tissue concentrations in patients undergoing elective cardiac surgery: Continuous vs bolus application. A pilot study.

AIMS: Surgical site infections contribute to morbidity and mortality after surgery. The authors hypothesized that higher antibiotic tissue concentrations can be reached for a prolonged time span by continuous administration of prophylactic cefuroxime compared to bolus administration. METHODS: Twelve patients undergoing elective cardiac surgery were investigated. Group A received 1.5 g cefuroxime as bolus infusions before surgery, and 12 and 24 hours thereafter. In group B, a continuous infusion of 3.0 g cefuroxime was started after a bolus of 1.5 g. Cefuroxim levels were determined in blood and tissue (microdialysis). T-test, Wilcoxon signed rank test and χ2 test were used for statistical analysis. RESULTS: The area under the curve (AUC) of plasma cefuroxime concentrations was greater in group B (399 [333-518]) as compared to group A (257 [177-297] h mg L-1 , [median and interquartile range], P = .026). Furthermore, a significantly longer percentage of time > minimal inhibitory concentrations of 2 mg L-1 (100% vs 50%), 4 mg L-1 (100% vs 42%), 8 mg L-1 (100% vs 17%) and 16 mg L-1 (83% vs 8%) was found for free plasma cefuroxime in group B. In group B, area under the curve in subcutaneous tissue (78 [61-113] h mg L-1 ) and median peak concentration (33 [26-38] mg L-1 ) were markedly higher compared to group A (P = 0.041 and P = .026, respectively). CONCLUSIONS: Higher cefuroxime concentrations were measured in plasma and subcutaneously over a prolonged period of time when cefuroxime was administered continuously. The clinical implication of this finding still has to be elucidated.

Non-pulsatile blood flow is associated with enhanced cerebrovascular carbon dioxide reactivity and an attenuated relationship between cerebral blood flow and regional brain oxygenation.

BACKGROUND: Systemic blood flow in patients on extracorporeal assist devices is frequently not or only minimally pulsatile. Loss of pulsatile brain perfusion, however, has been implicated in neurological complications. Furthermore, the adverse effects of absent pulsatility on the cerebral microcirculation are modulated similarly as CO2 vasoreactivity in resistance vessels. During support with an extracorporeal assist device swings in arterial carbon dioxide partial pressures (PaCO2) that determine cerebral oxygen delivery are not uncommon-especially when CO2 is eliminated by the respirator as well as via the gas exchanger of an extracorporeal membrane oxygenation machine. We, therefore, investigated whether non-pulsatile flow affects cerebrovascular CO2 reactivity (CVR) and regional brain oxygenation (rSO2). METHODS: In this prospective, single-centre case-control trial, we studied 32 patients undergoing elective cardiac surgery. Blood flow velocity in the middle cerebral artery (MCAv) as well as rSO2 was determined during step changes of PaCO2 between 30, 40, and 50 mmHg. Measurements were conducted on cardiopulmonary bypass during non-pulsatile and postoperatively under pulsatile blood flow at comparable test conditions. Corresponding changes of CVR and concomitant rSO2 alterations were determined for each flow mode. Each patient served as her own control. RESULTS: MCAv was generally lower during hypocapnia than during normocapnia and hypercapnia (p < 0.0001). However, the MCAv/PaCO2 slope during non-pulsatile flow was 14.4 cm/s/mmHg [CI 11.8-16.9] and 10.4 cm/s/mmHg [CI 7.9-13.0] after return of pulsatility (p = 0.03). During hypocapnia, non-pulsatile CVR (4.3 ± 1.7%/mmHg) was higher than pulsatile CVR (3.1 ± 1.3%/mmHg, p = 0.01). Independent of the flow mode, we observed a decline in rSO2 during hypocapnia and a corresponding rise during hypercapnia (p < 0.0001). However, the relationship between ΔrSO2 and ΔMCAv was less pronounced during non-pulsatile flow. CONCLUSIONS: Non-pulsatile perfusion is associated with enhanced cerebrovascular CVR resulting in greater relative decreases of cerebral blood flow during hypocapnia. Heterogenic microvascular perfusion may account for the attenuated ΔrSO2/ΔMCAv slope. Potential hazards related to this altered regulation of cerebral perfusion still need to be assessed. TRIAL REGISTRATION: The study was retrospectively registered on October 30, 2018, with Clinical Trial.gov (NCT03732651).

Seizures After Adult Cardiac Surgery and Interventional Cardiac Procedures.

The aim of this narrative review is to evaluate the incidence of seizures after adult cardiac surgery or cardiac interventions, to describe risk factors, and to provide suggestions regarding diagnostic measures and proper management. Based on published peer-reviewed articles, the authors demonstrate specific procedure-related risks for seizures. Early diagnosis, the identification of underlying causes, and avoidance of amenable risk factors are crucial to reduce associated long-term morbidity and mortality. Methods of early recognition of seizures, particularly focusing on the initiation of appropriate diagnostic measures, their management, and their timely treatment, are presented in the article.

Prognostic Impact of Persistent Thrombocytopenia During Extracorporeal Membrane Oxygenation: A Retrospective Analysis of Prospectively Collected Data From a Cohort of Patients With Left Ventricular Dysfunction After Cardiac Surgery.

OBJECTIVE: The prognostic impact of thrombocytopenia in patients supported by extracorporeal membrane oxygenation after cardiac surgery is uncertain. We investigated whether thrombocytopenia is independently predictive of poor outcome and describe the incidence and time course of thrombocytopenia in extracorporeal membrane oxygenation patients. DESIGN: Retrospective analysis of prospectively collected data. SETTING: Cardiosurgical ICU at a tertiary referral center. PATIENTS: Three hundred adult patients supported with venoarterial extracorporeal membrane oxygenation for more than 24 hours because of refractory cardiogenic shock after heart surgery between January 2001 and December 2014. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Two-way analysis of variance was used to compare the time course of platelet count changes between survivors and nonsurvivors. Using multiple Cox regression with time-dependent covariates, we investigated the impact of platelet count on 90-day mortality. In nonsurvivors, the daily incidence of moderate (< 100 - 50 × 10/L), severe (49 - 20 × 10/L), and very severe (< 20 × 10/L) thrombocytopenia was 50%, 54%, and 7%, respectively. Platelet count had a biphasic temporal pattern with an initial decrease until day 4-5 after the initiation of extracorporeal membrane oxygenation. Although a significant recovery of the platelet count was observed in survivors, a recovery did not occur in nonsurvivors (p = 0.0001). After adjusting for suspected confounders, moderate, severe, and very severe thrombocytopenia were independently associated with 90-day mortality. The highest risk was associated with severe (hazard ratio, 5.9 [2.7-12.6]; p < 0.0001) and very severe thrombocytopenia (hazard ratio, 25.9 [10.7-62.9], p < 0.0001). CONCLUSION: Thrombocytopenia is an independent risk factor for poor outcome in extracorporeal membrane oxygenation patients after cardiac surgery, with persistent severe thrombocytopenia likely reflecting a high degree of physiologic imbalance.

Accuracy of Continuous Cardiac Output Measurement With the LiDCOplus System During Intra-Aortic Counterpulsation After Cardiac Surgery.

OBJECTIVE: To evaluate the effect of intra-aortic counterpulsation on precision, accuracy, and concordance of continuous pulse contour cardiac output determined using LiDCOplus (LiDCO Group, London). DESIGN: Prospective trial. SETTING: University hospital critical care unit. PARTICIPANTS: Patients with intra-aortic balloon pump support in the 1:1 mode after elective or urgent cardiac surgery. INTERVENTIONS: Lithium dilution calibrated pulse contour cardiac output was compared with pulmonary artery bolus thermodilution cardiac output during hemodynamically stable conditions in the course of standardized postoperative management. MEASUREMENTS AND MAIN RESULTS: Fifty-one paired measurements demonstrated good correlation between the 2 methods (r = 0.88, p<0.001). Mean bias was -0.14±0.81 L/min, limits of agreement 1.48 to -1.77 L/min, and percentage error 28%. Concordance between the 2 techniques regarding directional changes>±10% cardiac output was 100% (p = 0.008). Trending ability was moderate when paired cardiac output changes were assessed using linear regression, 4-quadrant table, and polar plots. When changes <±10% of the reference cardiac output were excluded, 90% of the data pairs still lay within the 30° radial limits. Optimal timing of the balloon pump was indispensable for proper determination of pulse contour cardiac output. CONCLUSIONS: Because of the LiDCOplus-specific algorithm in determining stroke volume from the arterial pulse waveform, which differs from other devices, accuracy and precision of continuous pulse contour cardiac output only are affected insignificantly by intra-aortic counterpulsation. The authors nevertheless caution that the device should be recalibrated after major hemodynamic alterations or otherwise inexplicable changes of the pulse contour cardiac output to improve trending.

Intraoperative ventilation strategy during cardiopulmonary bypass attenuates the release of matrix metalloproteinases and improves oxygenation.

BACKGROUND: Patients undergoing open heart surgery with cardiopulmonary bypass (CPB) often develop a systemic immune reaction, characterized by an increase of proinflammatory and anti-inflammatory mediators. We previously demonstrated that continued mechanical ventilation during CPB reduces this response. We hypothesized that this strategy may also impact on matrix metalloproteinase (MMP) release. MATERIAL AND METHODS: Thirty consecutive patients undergoing coronary artery bypass grafting with CPB were randomized into a ventilated (VG) (n = 15) and a standard non-ventilated group (NVG) (n = 15). Blood was collected at the beginning, at the end of surgery, and on the five consecutive days. MMPs, tissue inhibitor of matrix metalloproteinase 1 (TIMP-1), and lipocalin 2 (LCN2) were measured by enzyme-linked immunosorbent assay. Parameters of transpulmonary oxygen transport were assessed at different time points. RESULTS: MMP-8, MMP-9, and LCN2 were significantly lower at the end of surgery in VG compared with those in NVG patients (MMP-8 [ng/mL]: 7.1 [3.5] versus 12.5 [7.7], P = 0.02; MMP-9 [ng/mL]: 108 [42] versus 171 [98], P = 0.029; LCN2 [ng/mL]: 109 [42] versus 171 [98], P = 0.03). TIMP-1 concentrations were lower on postoperative day one, (TIMP-1 [ng/mL]: 174 [55] versus 273 [104], P = 0.003), whereas MMP-3 levels were lower on postoperative days four and five (MMP-3 [ng/mL]: 44 [17] versus 67 [35], P = 0.026). The arterial partial pressure of oxygen/fraction of inspired oxygen ratio was significantly higher in VG patients throughout the postoperative observation period, which did not affect the length of postoperative ventilatory support. CONCLUSIONS: Continued mechanical ventilation during CPB reduces serum levels of MMPs, their inhibitor TIMP-1 and LCN2, which preserves MMP-9 activity. The present study suggests that continued mechanical ventilation improves postoperative oxygenation and could potentially prevent aggravation of lung injury after CPB.

Low tidal volume ventilation during cardiopulmonary bypass reduces postoperative chemokine serum concentrations.

BACKGROUND: Open-heart surgery with cardiopulmonary bypass (CPB) is associated with a generalized immune response and postoperative lung dysfunction. Chemokines are involved in the pathogenesis of postoperative lung dysfunction. We investigated whether continued mechanical ventilation during CPB has an impact on chemokine serum concentrations. METHODS: A total of 30 patients undergoing coronary artery bypass graft operation were randomized to either continuous ventilated group (n=15) or nonventilated group (n=15). Blood samples were drawn at the beginning and at the end of surgery and on the 5 consecutive days. Serum CCL2, CCL4, and CCL20 concentrations were measured and given as mean ± standard deviation. RESULTS: Chemokine concentrations were elevated at the end of surgery in both groups. CCL2 and CCL4 levels returned to baseline on postoperative day (POD)-1 in the ventilation group and stayed elevated in the nonventilation group. CCL4 serum levels were significantly lower in ventilated-group patients on POD-1 (10.9 [39.0] vs. 153.2 [168.1]; p=0.005), POD-2 (16.8 [36.8] vs. 147.9 [165.4]; p=0.019), POD-3 (14.2 [24.0] vs. 97.9 [87.1]; p=0.005), and POD-5 (6.5 [25.0] vs. 33.6 [38.4]; p=0.045). CONCLUSION: Continued mechanical ventilation during CPB results in reduced CCL4 concentrations on POD-1 to -5.

Oxygen Consumption Predicts Long-Term Outcome of Patients with Left Ventricular Assist Devices.

Reduced oxygen consumption (VO2), either due to insufficient oxygen delivery (DO2), microcirculatory hypoperfusion and/or mitochondrial dysfunction, has an impact on the adverse short- and long-term survival of patients after cardiac surgery. However, it is still unclear whether VO2 remains an efficient predictive marker in a population in which cardiac output (CO) and consequently DO2 is determined by a left ventricular assist device (LVAD). We enrolled 93 consecutive patients who received an LVAD with a pulmonary artery catheter in place to monitor CO and venous oxygen saturation. VO2 and DO2 of in-hospital survivors and non-survivors were calculated over the first 4 days. Furthermore, we plotted receiver-operating curves (ROC) and performed a cox-regression analysis. VO2 predicted in-hospital, 1- and 6-year survival with the highest area under the curve of 0.77 (95%CI: 0.6-0.9; p = 0.0004). A cut-off value of 210 mL/min VO2 stratified patients regarding mortality with a sensitivity of 70% and a specificity of 81%. Reduced VO2 was an independent predictor for in-hospital, 1- and 6-year mortality with a hazard ratio of 5.1 (p = 0.006), 3.2 (p = 0.003) and 1.9 (p = 0.0021). In non-survivors, VO2 was significantly lower within the first 3 days (p = 0.010, p < 0.001, p < 0.001 and p = 0.015); DO2 was reduced on days 2 and 3 (p = 0.007 and p = 0.003). In LVAD patients, impaired VO2 impacts short- and long-term outcomes. Perioperative and intensive care medicine must, therefore, shift their focus from solely guaranteeing sufficient oxygen supply to restoring microcirculatory perfusion and mitochondrial functioning.

A Prospective Observational Study on Multiplate®-, ROTEM®- and Thrombin Generation Examinations Before and Early After Implantation of a Left Ventricular Assist Device (LVAD).

Background: Heart failure patients are frequently on coagulation-active medications before LVAD implantation and perioperative bleeding is a frequent complication after left ventricular assist device (LVAD) implantation. The role of point-of-care coagulation tests in assessing bleeding risk for LVAD implantation and the early postoperative time course of these tests is not well established. Methods: We prospectively enrolled 25 patients with terminal heart failure undergoing LVAD implantation. Study related TRAP-, ASPI- and ADP- tests of Multiplate® platelet aggregometry, ROTEM® rotational thromboelastometry (INTEM, EXTEM, FIBTEM), thrombin generation assay and conventional laboratory studies were measured at 11 predefined time-points during the first 21 postoperative days. We examined if preoperative TRAP-, ASPI-, ADP- and ROTEM values are correlated with estimated total blood loss (primary outcome parameter) during the first 21 days after LVAD implantation and compared the baseline values of these measurements between patients with a bleeding event to those without. We performed Spearman's correlation and non-parametric tests for paired and non-paired comparisons. Results: 7 out of 25 (28%) patients experienced a bleeding event of which 4 required surgical revision. Of the preoperatively performed measurements the TRAP test [Spearman's Rho (ρ) = -0.5, p = 0.01], INTEM CFT (ρ = 0.72, p < 0.001), INTEM alpha (-0.7, p < 0.001), EXTEM MCF (ρ = -0.63; p < 0.001), EXTEM alpha (ρ = -0.67; p < 0.001), FIBTEM MCF (ρ = -0.41; p = 0.042), Fibrinogen (Clauss) (ρ = -0.5; p = 0.011), Anti-thrombin activity (ρ = -0.49; p = 0.013) and platelet count (ρ = -0.42; p = 0.034) were significantly correlated to total blood loss. Patients undergoing a surgical bleeding revision had significantly reduced values in TRAP-[31.5 IQR (17.25-43.5U) vs. 69 IQR (52.5-87U); p = 0.004], ASPI-[16.5 IQR (5.5-35.7U) vs. 39 IQR (24.5-62.5U); p = 0.038], ADP-[30 IQR (22-69U) vs. 12.5 IQR (8.7-21.5U); p = 0.01], EXTEM MCF-[63 IQR (57.7-63.7) vs. 67 IQR (65-75.5); p = 0.019] and EXTEM alpha [74 IQR (68.75-74) vs. 79 IQR (78-80.5); p = 0.002] values before LVAD implantation. Conclusion: Multiplate® and ROTEM® measurements before LVAD implantation may identify LVAD candidates with platelet dysfunction and alterations of the primary hemostasis and could guide anesthetists and intensive care practitioners in bleeding risk stratification and in the perioperative clinical management.

The Impact of Nonconvulsive Status Epilepticus after Cardiac Surgery on Outcome.

Neurological complications after heart surgery are associated with tremendous morbidity and mortality. Nonconvulsive status epilepticus (NCSE), which can only be verified by EEG, may cause secondary brain damage. Its frequency and its impact on outcomes after cardiac surgery is still unclear. We collected the neurological files and clinical data of all our patients after heart surgery who, in the course of their ICU stay, had been seen by a neurologist who ordered an EEG. Within 18 months, 1457 patients had cardiac surgery on cardiopulmonary bypass. EEG was requested for 89 patients. Seizures were detected in 39 patients and NCSE was detected in 11 patients. Open heart surgery was performed in all 11 NSCE patients, of whom eight showed concomitant brain insults. None had a history of epilepsy. Despite the inhibition of seizure activity with antiseizure medication, clinical improvement was only noted in seven NCSE patients, three of whom were in cerebral performance category 2 and four in category 3 at hospital discharge. The four patients without neurological benefit subsequently died in the ICU. The occurrence of NCSE after open cardiac surgery is significant and frequently associated with brain injury. It seems prudent to perform EEG studies early to interrupt seizure activity and mitigate secondary cerebral injury.

Absent Metabolic Transition from the Early to the Late Period in Non-Survivors Post Cardiac Surgery.

After major surgery, longitudinal changes in resting energy expenditure (REE) as well as imbalances in oxygen delivery (DO2) and distribution and processing (VO2) may occur due to dynamic metabolic requirements, an impaired macro- and microcirculatory flow and mitochondrial dysfunction. However, the longitudinal pattern of these parameters in critically ill patients who die during hospitalization remains unknown. Therefore, we analyzed in 566 patients who received a pulmonary artery catheter (PAC) their REE, DO2, VO2 and oxygen extraction ratio (O2ER) continuously in survivors and non-survivors over the first 7 days post cardiac surgery, calculated the percent increase in the measured compared with the calculated REE and investigated the impact of a reduced REE on 30-day, 1-year and 6-year mortality in a uni- and multivariate model. Only in survivors was there a statistically significant transition from a negative to a positive energy balance from day 0 until day 1 (Day 0: −3% (−18, 14) to day 1: 5% (−9, 21); p < 0.001). Furthermore, non-survivors had significantly decreased DO2 during the first 4 days and reduced O2ER from day 2 until day 6. Additionally, a lower REE was significantly associated with a worse survival at 30 days, 1 year and 6 years (p = 0.009, p < 0.0001 and p = 0.012, respectively). Non-survivors seemed to be unable to metabolically adapt from the early (previously called the 'ebb') phase to the later 'flow' phase. DO2 reduction was more pronounced during the first three days whereas O2ER was markedly lower during the following four days, suggesting a switch from a predominantly limited oxygen supply to prolonged mitochondrial dysfunction. The association between a reduced REE and mortality further emphasizes the importance of REE monitoring.

Follistatin-like 1 and Biomarkers of Neutrophil Activation Are Associated with Poor Short-Term Outcome after Lung Transplantation on VA-ECMO.

The investigation of biomarkers associated with undesired outcome following lung transplantation (LuTX) is essential for a better understanding of the underlying pathophysiology, an earlier identification of susceptible recipients and the development of targeted therapeutic options. We therefore determined the longitudinal perioperative course of putative cytokines related to neutrophil activation (chemokine CC motif ligand 4 (CCL-4), interleukin (IL)-23 and Lipocalin 2 (LCN2)) and a cytokine that has been implicated in graft-versus-host disease (Follistatin-like 1 (FSTL1)) in 42 consecutive patients undergoing LuTX. We plotted receiver-operating curves (ROC) to assess the predictive power of the measured cytokines for short-term outcomes namely primary graft dysfunction (PGD), early complications requiring extracorporeal membrane oxygenation (ECMO), and a high postoperative sequential organ failure assessment (SOFA). All cytokines increased immediately after surgery. ROC analyses determined significant associations between CCL4 and a high SOFA score (area under the curve (AUC) 0.74 (95%CI:0.5−0.9; p < 0.05), between LCN2 and postoperative ECMO support (AUC 0.73 (95%CI:0.5−0.9; p < 0.05), and between FSTL1 and PGD (AUC 0.70 (95%CI:0.5−0.9; p < 0.05). The serum concentrations of the neutrophil-derived cytokines LCN2 and CCL4 as well as FSTL1 were all related to poor outcome after LuTX. The specific predictive power, however, still has to be assessed in larger trials. The potential role of FSTL1 as a biomarker in the development of PGD could be of great interest particularly since this protein appears to play a crucial role in allograft tolerance.