Prevalence and Risk Factors for Weaning Failure From Venovenous Extracorporeal Membrane Oxygenation in Patients With Severe Acute Respiratory Insufficiency.

OBJECTIVE: Analysis of the prevalence and risk factors for weaning failure from venovenous extracorporeal membrane oxygenation (VV-ECMO) in patients with severe acute respiratory insufficiency. DESIGN: Single-center retrospective observational study. SETTING: Sixteen beds medical ICU at the University Hospital Regensburg. PATIENTS: Two hundred twenty-seven patients with severe acute respiratory insufficiency requiring VV-ECMO support between October 2011 and December 2017. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Patients meeting our ECMO weaning criteria (Sp o2 ≥ 90% with F io2 ≤ 0.4 or Pa o2 /F io2 > 150 mm Hg, pH = 7.35-7.45, positive end-expiratory pressure ≤ 10 cm H 2 O, driving pressure < 15 cm H 2 O, respiratory rate < 30/min, tidal volume > 5 mL/kg, ECMO bloodflow ≈ 1. 5 L/min, sweep gas flow ≈ 1 L/min, heart rate < 120/min, systolic blood pressure 90-160 mm Hg, norepinephrine < 0.2 µg/[kg*min]) underwent an ECMO weaning trial (EWT) with pausing sweep gas flow. Arterial blood gas analysis, respiratory and ventilator parameters were recorded prior, during, and after EWTs. Baseline data, including demographics, vitals, respiratory, ventilator, and laboratory parameters were recorded at the time of cannulation. One hundred seventy-nine of 227 (79%) patients were successfully decannulated. Ten patients (4%) underwent prolonged weaning of at least three failed EWTs before successful decannulation. The respiratory rate (19/min vs 16/min, p = 0.002) and Pa co2 (44 mm Hg vs 40 mm Hg, p = 0.003) were higher before failed than successful EWTs. Both parameters were risk factors for ECMO weaning failure (Pa co2 : odds ratio [OR] 1.05; 95% CI, 1.001-1.10; p = 0.045; respiratory rate: OR 1.10; 95% CI, 1.04-1.15; p < 0.001) in multivariable analysis. The rapid shallow breathing index [42 (1/L*min), vs 35 (1/L*min), p = 0.052) was higher before failed than successful EWTs. The decline of Sa o2 and Pa o2 /F io2 during EWTs was higher in failed than successful trials. CONCLUSIONS: Seventy-nine percent of patients were successfully decannulated with only 4% needing prolonged ECMO weaning. Before EWT only parameters of impaired ventilation (insufficient decarboxylation, higher respiratory rate) but not of oxygenation were predictive for weaning failure, whereas during EWT-impaired oxygenation was associated with weaning failure.

Outcome after veno-venous extracorporeal membrane oxygenation in elderly compared to younger patients: A 14-year retrospective observational study.

BACKGROUND: The outcome after veno-venous extracorporeal membrane oxygenation in elderly patients is supposed to be unsatisfactory. Our primary aim was to determine the influence of advanced age on short- and long-term outcomes; the secondary aim was to analyze risk factors for impaired outcomes. METHODS: Between January 2006 and June 2020, 755 patients received V-V ECMO support at our department. Patients were grouped according to age (18-49.9, 50-59.9, 60-69.9, ≥70 years old), and then retrospectively analyzed for short- and long-term outcomes. Risk factors for in-hospital mortality and death during follow-up were assessed using multivariate regression analysis. RESULTS: Duration of V-V ECMO support was comparable between all groups median (8-10 days, p = 0.256). Likewise, the weaning rate was comparable in all age groups 68.2%-76.5%; (p = 0.354), but in-hospital mortality was significantly climbing with increasing age (<50 years 30.1%/n = 91 vs. 50-59.9 years 37.1%/n = 73, vs. 60-69.9 years 45.6%/n = 78 vs. ≥70 years 51.8%/n = 44; p < 0.001). Older age groups also showed significantly reduced cerebral performance category scores. The multivariate logistic analysis yielded age, acute and chronic hemodialysis, bilirubin on day 1 of support, malignancy, and primary lung disease as relevant risk factors for in-hospital mortality. Age, coronary artery disease, presence of another primary lung disease, malignancy, and immunosuppression were risk factors for death during follow-up. CONCLUSION: In V-V ECMO patients, advanced age is associated with more comorbidity, impaired short- and long-term outcome, and worse neurological outcome.

Outcome after veno-arterial extracorporeal membrane oxygenation in elderly patients: A 14-year single-center experience.

BACKGROUND: Use of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) in elderly patients is controversial because of presumed poor outcome. Our primary aim was to determine the influence of advanced age on short- and long-term outcome; the secondary aim was to analyze risk factors for impaired outcome. METHODS: Between January 2006 and June 2020, 645 patients underwent VA-ECMO implantation in our department. The patients were categorized into four groups:<50, 50-59.9, 60-69.9 and ≥70 years old. Data were retrospectively analyzed for short- and long-term outcome. Risk factors for in-hospital mortality and mortality during follow-up were assessed using multivariate regression analysis. RESULTS: VA-ECMO support duration was comparable in all age groups (median 3 days). Weaning rates were 60.8%/n = 104 (<50 years), 51.4%/n = 90 (50-59.9 years), 58.8%/n = 107 (60-69.9), and 67.5%/n = 79 (≥70, p = 0.048). Hospital mortality was highest in the patients aged 50-59.9 years (68%/n = 119), but not in the elderly patients (60-69.9, ≥70:62.1%/n = 113, 58,1%/n = 68). At discharge, the cerebral performance category scores were superior in the patients <50 years. Multivariate logistic regression analysis revealed chronic kidney failure requiring hemodialysis, duration of cardiopulmonary resuscitation, and elevated blood lactate levels before VA-ECMO, but not age as predictors of in-hospital mortality. Cox's regression disclosed age as relevant risk factor for death during follow-up. The patients' physical ability was comparable in all age groups. CONCLUSION: VA-ECMO support should not be declined in patients only because of advanced age. Mortality and neurological status at hospital discharge and during follow-up were comparable in all age groups.

Omental Flap for Complex Sternal Wounds and Mediastinal Infection Following Cardiac Surgery.

INTRODUCTION: Omental flap (OF) is a traditional surgical option to counteract severe postcardiotomy mediastinal infection and to cover extensive sternal defects. We reviewed our experience with omental flap transfer (OFT) in various clinical circumstances, in which omentoplasty may be considered by cardiac surgeons. METHODS: Twenty-one patients, who underwent OFT from January 2012 to December 2021, were studied. The main indication was treatment of infected foreign material implants including vascular grafts and ventricular assist devices or prevention of its infection (16 patients). In five patients, an OFT was used to cure mediastinitis following deep sternal wound infection after median sternotomy. RESULTS: All patients had a high surgical risk with 3 ± 1.9 previous sternotomies and a mean Euro Score II of 55.0 ± 20.1. OF was successful in its prophylactic or therapeutic purpose in all patients, no complications related to the operative procedure were noted, that is, no early or late flap failure and no herniation of abdominal organs occurred. In-hospital mortality was six patients as three patients each died from multiple organ dysfunction syndrome and cerebral hemorrhage. All fifteen patients discharged demonstrated rapid recovery, complete wound healing without fistula, and no late gastrointestinal complications. The mean follow-up of 18 months was uneventful. CONCLUSION: OFT seems to be an excellent solution for extensive mediastinal and deep sternal wound infections.

Enabling the control of reperfusion parameters in out-of-hospital cardiac arrest: First applications of the CARL system.

INTRODUCTION: There is increasing evidence for extracorporeal cardiopulmonary resuscitation (ECPR) as a rescue therapy for selected patients in refractory cardiac arrest (CA). Besides patient selection, the control of reperfusion parameters is of eminent importance. Especially in out-of-hospital CA, monitoring and individualized, targeted reperfusion remains a great challenge for emergency personnel. The CARL® system is designed to enable an early control of a variety of reperfusion parameters and to pursue a targeted reperfusion strategy in ECPR. CASE PRESENTATION: We report the first 10 ECPR applications of the CARL® system in Regensburg, Germany. Early blood gas analysis, oxygen titration and pressure monitoring were feasible and enabled an individualized and targeted reperfusion strategy in all patients. After suffering from refractory CA and prolonged resuscitation attempts, five out of the first 10 patients survived and were successfully discharged from the hospital (CPC one on hospital discharge). CONCLUSION: Application of the CARL® system contributed to early monitoring and control of reperfusion parameters. Whether targeted ECPR may have the potential to improve outcomes in refractory OHCA remains the subject of future investigations.

Contribution of High Viral Loads, Detection of Viral Antigen and Seroconversion to Severe Acute Respiratory Syndrome Coronavirus 2 Infectivity.

BACKGROUND: From a public health perspective, effective containment strategies for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) should be balanced with individual liberties. METHODS: We collected 79 respiratory samples from 59 patients monitored in an outpatient center or in the intensive care unit of the University Hospital Regensburg. We analyzed viral load by quantitative real-time polymerase chain reaction, viral antigen by point-of-care assay, time since onset of symptoms, and the presence of SARS-CoV-2 immunoglobulin G (IgG) antibodies in the context of virus isolation from respiratory specimens. RESULTS: The odds ratio for virus isolation increased 1.9-fold for each log10 level of SARS-CoV-2 RNA and 7.4-fold with detection of viral antigen, while it decreased 6.3-fold beyond 10 days of symptoms and 20.0-fold with the presence of SARS-CoV-2 antibodies. The latter was confirmed for B.1.1.7 strains. The positive predictive value for virus isolation was 60.0% for viral loads >107 RNA copies/mL and 50.0% for the presence of viral antigen. Symptom onset before 10 days and seroconversion predicted lack of infectivity with negative predictive values of 93.8% and 96.0%. CONCLUSIONS: Our data support quarantining patients with high viral load and detection of viral antigen and lifting restrictive measures with increasing time to symptom onset and seroconversion. Delay of antibody formation may prolong infectivity.

Multi-organ dysfunction syndrome in patients undergoing extracorporeal life support.

BACKGROUND: Multiple organ failure is a common complication in patients undergoing ECLS significantly affecting patient outcomes. Gaining knowledge about the mechanisms of onset, clinical course, risk factors, and potential therapeutic targets is highly desirable. METHODS: Data of 354 patients undergoing ECLS with one-, two, three-, and four organ failures were retrospectively analyzed. Incidence of multiple organ dysfunction (MODS), its impact on survival, risk factors for its occurrence, and the impact of proinflammatory mediators on the occurrence of MODS in patients undergoing ECLS were investigated. RESULTS: The median follow-up was 66 (IQR 6; 820) days. 245 (69.2%) patients could be weaned from ECLS, 30-day survival and 1-year survival were 194 (54.1%) and 157 (44.4%), respectively. The duration of mechanical support was 4 (IQR 2; 7) days in the median. Increasing severity of MODS resulted in significant prolongation of mechanical circulatory support and worsening of the outcome. Liver dysfunction had the strongest impact on patient mortality (OR = 2.5) and survival time (19 vs 367 days). The serum concentration of analyzed interleukins rose significantly with each, additional organ affected by dysfunction (p < 0.001). All analyzed proinflammatory cytokines showed significant predictivity relative to the occurrence of MODS with interleukin 8 serum level prior to ECLS showing the strongest predictive potential for the occurrence of MODS (AUC 0.78). CONCLUSION: MODS represents a frequent complication in patients undergoing ECLS with a significant impact on survival. Proinflammatory cytokines show prognostic capacity regarding the occurrence and severity of multi-organ dysfunction.

25 Years' Experience with Redo Operations in Cardiac Surgery-Third-Time Sternotomy Procedures.

BACKGROUND: Over the years, open heart surgery has become more complex, and especially reoperative surgery, more demanding. The risk of third-time or more sternotomy procedures is unclear. METHODS: We reviewed our institutional experience of 25 years based on two generations of cardiac surgeons in a German university medical center to document frequency, outcome, and complications of the various types of open heart procedures. RESULTS: Overall, we included 104 patients with a mean age of 64 ± 13 years. The EuroSCORE II (European System for Cardiac Operative Risk Evaluation) calculated an average mortality risk of 15.7 ± 15.4%. Subgroup comparison of isolated coronary artery bypass grafting (CABG), aortic valve replacement, and mitral valve replacement procedures did not delineate significantly different risk profiles except for the incidence of acute myocardial infarction, which was present in every second patient (53.3%) scheduled for CABG surgery. The time interval to previous surgery was 4.7 ± 6.3 years on average. Most frequent surgical procedures were valve operations, which were accomplished in 72 patients (69.2%), whereas coronary bypass surgery was performed in 23 patients (22.1%) only. Combined procedures were performed in 27 patients. Complex aortic arch replacement with a frozen elephant trunk procedure was necessary in six patients. Overall, 30-day survival was 81.7%. CONCLUSION: In conclusion, third-time and more sternotomy procedures offer acceptable outcome and should therefore be considered in appropriate patients.

A highly specific and sensitive serological assay detects SARS-CoV-2 antibody levels in COVID-19 patients that correlate with neutralization.

OBJECTIVE: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic challenges national health systems and the global economy. Monitoring of infection rates and seroprevalence can guide public health measures to combat the pandemic. This depends on reliable tests on active and former infections. Here, we set out to develop and validate a specific and sensitive enzyme linked immunosorbent assay (ELISA) for detection of anti-SARS-CoV-2 antibody levels. METHODS: In our ELISA, we used SARS-CoV-2 receptor-binding domain (RBD) and a stabilized version of the spike (S) ectodomain as antigens. We assessed sera from patients infected with seasonal coronaviruses, SARS-CoV-2 and controls. We determined and monitored IgM-, IgA- and IgG-antibody responses towards these antigens. In addition, for a panel of 22 sera, virus neutralization and ELISA parameters were measured and correlated. RESULTS: The RBD-based ELISA detected SARS-CoV-2-directed antibodies, did not cross-react with seasonal coronavirus antibodies and correlated with virus neutralization (R2 = 0.89). Seroconversion started at 5 days after symptom onset and led to robust antibody levels at 10 days after symptom onset. We demonstrate high specificity (99.3%; N = 1000) and sensitivity (92% for IgA, 96% for IgG and 98% for IgM; > 10 days after PCR-proven infection; N = 53) in serum. CONCLUSIONS: With the described RBD-based ELISA protocol, we provide a reliable test for seroepidemiological surveys. Due to high specificity and strong correlation with virus neutralization, the RBD ELISA holds great potential to become a preferred tool to assess thresholds of protective immunity after infection and vaccination.

Argatroban versus heparin in patients without heparin-induced thrombocytopenia during venovenous extracorporeal membrane oxygenation: a propensity-score matched study.

BACKGROUND: During venovenous extracorporeal membrane oxygenation (vvECMO), direct thrombin inhibitors are considered by some potentially advantageous over unfractionated heparin (UFH). We tested the hypothesis that Argatroban is non-inferior to UFH regarding thrombosis and bleeding during vvECMO. METHODS: We conducted a propensity-score matched observational non-inferiority study of consecutive patients without heparin-induced-thrombocytopenia (HIT) on vvECMO, treated between January 2006 and March 2019 in the medical intensive care unit at the University Hospital Regensburg. Anticoagulation was realized with UFH until August 2017 and with Argatroban from September 2017 onwards. Target activated partial thromboplastin time was 50 ± 5seconds in both groups. Primary composite endpoint was major thrombosis and/or major bleeding. Major bleeding was defined as a drop in hemoglobin of ≥ 2 g/dl/day or in transfusion of ≥ 2 packed red cells/24 h, or retroperitoneal, cerebral, or pulmonary bleeding. Major thrombosis was defined as obstruction of > 50% of the vessel lumen diameter by means of duplex sonography. We also assessed technical complications such as oxygenator defects or pump head thrombosis, the time-course of platelets, and the cost of anticoagulation (including HIT-testing). RESULTS: Out of 465 patients receiving UFH, 78 were matched to 39 patients receiving Argatroban. The primary endpoint occurred in 79% of patients in the Argatroban group and in 83% in the UFH group (non-inferiority for Argatroban, p = 0.026). The occurrence of technical complications was equally distributed (Argatroban 49% vs. UFH 42%, p = 0.511). The number of platelets was similar in both groups before ECMO therapy but lower in the UFH group after end of ECMO support (median [IQR]: 141 [104;198]/nl vs. 107 [54;171]/nl, p = 0.010). Anticoagulation costs per day of ECMO were higher in the Argatroban group (€26 [13.8;53.0] vs. €0.9 [0.5;1.5], p < 0.001) but not after accounting for blood products and HIT-testing (€63 [42;171) vs. €40 [17;158], p = 0.074). CONCLUSION: In patients without HIT on vvECMO, Argatroban was non-inferior to UFH regarding bleeding and thrombosis. The occurrence of technical complications was similarly distributed. Argatroban may have less impact on platelet decrease during ECMO, but this finding needs further evaluation. Direct drug costs were higher for Argatroban but comparable to UFH after accounting for HIT-testing and transfusions.

ECMO in COVID-19-prolonged therapy needed? A retrospective analysis of outcome and prognostic factors.

BACKGROUND: The role of venovenous extracorporeal membrane oxygenation (VV ECMO) in patients with COVID-19-induced acute respiratory distress syndrome (ARDS) still remains unclear. Our aim was to investigate the clinical course and outcome of those patients and to identify factors associated with the need for prolonged ECMO therapy. METHODS: A retrospective single-center study on patients with VV ECMO for COVID-19-associated ARDS was performed. Baseline characteristics, ventilatory and ECMO parameters, and laboratory and virological results were evaluated over time. Six months follow-up was assessed. RESULTS: Eleven of 16 patients (68.8%) survived to 6 months follow-up with four patients requiring short-term (<28 days) and seven requiring prolonged (⩾28 days) ECMO support. Lung compliance before ECMO was higher in the prolonged than in the short-term group (28.1 (28.8-32.1) ml/cmH2O vs 18.7 (17.7-25.0) ml/cmH2O, p = 0.030). Mechanical ventilation before ECMO was longer (19 (16-23) days vs 5 (5-9) days, p = 0.002) and SOFA score was higher (12.0 (10.5-17.0) vs 10.0 (9.0-10.0), p = 0.002) in non-survivors compared to survivors. Low viral load during the first days on ECMO tended to indicate worse outcomes. Seroconversion against SARS-CoV-2 occurred in all patients, but did not affect outcome. CONCLUSIONS: VV ECMO support for COVID-19-induced ARDS is justified if initiated early and at an experienced ECMO center. Prolonged ECMO therapy might be required in those patients. Although no relevant predictive factors for the duration of ECMO support were found, the decision to stop therapy should not be made dependent of the length of ECMO treatment.

Evaluation of comprehensiveness and reliability of electronic health records concerning resuscitation efforts within academic intensive care units: a retrospective chart analysis.

BACKGROUND: According to the literature, the validity and reliability of medical documentation concerning episodes of cardiopulmonary resuscitation (CPR) is suboptimal. However, little is known about documentation quality of CPR efforts during intensive care unit (ICU) stays in electronic patient data management systems (PDMS). This study analyses the reliability of CPR-related medical documentation within the ICU PDMS. METHODS: In a retrospective chart analysis, PDMS records of three ICUs of a single university hospital were searched over 5 y for CPR check marks. Respective datasets were analyzed concerning data completeness and data consistency by comparing the content of three documentation forms (physicians' log, nurses' log, and CPR incident form), as well as physiological and therapeutic information of individual cases, for missing data and plausibility of CPR starting time and duration. To compare data reliability and completeness, a quantitative measure, the Consentaneity Index (CI), is proposed. RESULTS: One hundred sixty-five datasets were included into the study. In 9% (n = 15) of cases, there was neither information on the time points of CPR initiation nor on CPR duration available in any data source. Data on CPR starting time and duration were available from at least two data sources in individual cases in 54% (n = 90) and 45% (n = 74), respectively. In these cases, the specifications of CPR starting time did differ by a median ± interquartile range of 10.0 ± 18.5 min, CPR duration by 5.0 ± 17.3 min. The CI as a marker of data reliability revealed a low consistency of CPR documentation in most cases, with more favorable results, if the time interval between the CPR episode and the time of documentation was short. CONCLUSIONS: This study reveals relevant proportions of missing and inconsistent data in electronic CPR documentation in the ICU setting. The CI is suggested as a tool for documentation quality analysis and monitoring of improvements.

Percutaneous Cannulation for Extracorporeal Life Support in Severely and Morbidly Obese Patients.

BACKGROUND: Extracorporeal life support systems are well-established devices for treating patients with acute cardiopulmonary failure. Severe or morbid obesity may result in complications such as limb ischemia, bleeding, unsuccessful cannulation, or infection at the cannulation sites. This article reports on our experience with cannulation and associated complications in severely and morbidly obese patients. METHODS: Between January 2006 and September 2016, 153 severely or morbidly obese patients with a body mass index >35 kg/m2 were cannulated percutaneously for extracorporeal life support at our center. Among those, 115 patients were treated with venovenous extracorporeal membrane oxygenation (VV ECMO) for acute lung failure and 38 patients with venoarterial extracorporeal membrane oxygenation (VA ECMO) for cardiogenic shock. Complications related to percutaneous access and long-term follow-up were analyzed retrospectively. Primary focus was on the success of cannulation, outcome, thrombosis, bleeding, limb ischemia, and infection at the cannulation site. Normal-weight patients receiving extracorporeal life support served as control. RESULTS: Percutaneous cannulation was successfully performed in all patients. Eighty-five (74%) patients were weaned from VV ECMO and 20 (52%) patients were weaned from VA ECMO. Limb ischemia requiring surgical intervention occurred in 5 (3%) patients, bleeding in 7 (5%) patients, and wound infection in 3 (2%) patients. In all other patients, decannulation was uneventful. These data as well as the long-term survival rates were comparable to those of normal-weight patients (P > .05). CONCLUSION: Percutaneous vessel cannulation for extracorporeal life support systems is generally feasible. Therefore, percutaneous cannulation may well be performed in severely and morbidly obese patients. Patient outcome rather depends on appropriate support than on anatomy.

The impact of interleukin serum levels on the prognosis of patients undergoing venoarterial extracorporeal membrane oxygenation.

Extracorporeal life support is increasingly used in the treatment of patients presenting with cardiogenic shock or in need of cardiopulmonary resuscitation. Identifying therapeutic targets and factors associated with the prognosis are highly desirable. The present study analyzed the impact of interleukin 6 and 8 on the outcome of patients undergoing venoarterial extracorporeal membrane oxygenation (VA ECMO). Interleukin 6 and 8 serum levels of 329 patients were analyzed prior to, on days 1 and 5 of VA ECMO therapy. Interleukin 6 and 8 serum levels of surviving and nonsurviving patients were compared. At time points with significant differences, receiver operating characteristics and cutoff levels were analyzed to determine the prognostic value of interleukin serum levels. Survival analysis was performed to compare patients above and below cutoff levels. Interleukin 6 serum levels were significantly elevated in nonsurviving patients prior to VA ECMO initiation. Interleukin 6 and 8 serum levels in nonsurviving patients were significantly elevated on day 1 of VA ECMO. Receiver operating characteristics analysis revealed significant prognostic impact of interleukin 6 and 8 on day 1 of VA ECMO (AUC 0.70 and 0.72). Survival analysis comparing patients above and below the cutoff showed a 1-year survival of 32.6% for IL6 and 20.8% for IL8 above, as well as 66.9% for IL6 and 61.9% for IL8 below the cutoff (P < .05). Interleukin 6 and 8 serum levels demonstrated prognostic value early in VA ECMO therapy. The technical applicability of interleukin reduction raises interest in interleukins 6 and 8 as therapeutic targets.

Incidence and Risk Factors for Cannula-Related Venous Thrombosis After Venovenous Extracorporeal Membrane Oxygenation in Adult Patients With Acute Respiratory Failure.

OBJECTIVES: Venovenous extracorporeal membrane oxygenation is indicated in patients with severe refractory acute respiratory failure. Venous thrombosis due to indwelling catheters is a frequent complication. The aim of this study was to analyze the incidence of cannula-related thrombosis and its risk factors after venovenous extracorporeal membrane oxygenation. DESIGN: Retrospective observational study. SETTING: A medical ICU at the University Hospital Regensburg. PATIENTS: We analyzed consecutive patients with severe respiratory failure (PaO2/FIO2 < 85 mm Hg and/or respiratory acidosis with pH < 7.25) who were successfully treated with venovenous extracorporeal membrane oxygenation in a medical ICU between 2010 and 2017. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: After extracorporeal membrane oxygenation weaning, duplex sonography or CT was conducted to detect cannula-related thrombosis. Thrombosis was classified as a large thrombosis by vein occlusion of greater than 50%. The incidence of thrombosis was correlated with risk factors such as coagulation variables (mean activated partial thromboplastin time ≤ 50 s, international normalized ratio antithrombin III, fibrinogen, plasma-free hemoglobin, platelets, and decline in D-dimer ≤ 50% the day after decannulation), cannula size, time on venovenous extracorporeal membrane oxygenation, renal failure, and underlying malignant disease. Data cut-off points were identified by receiver operating characteristic analysis. One-hundred seventy-two of 197 patients (87%) were screened. One-hundred six patients (62%) showed thrombosis that was considered large in 48 of 172 (28%). The incidence of thrombosis was higher in patients with a mean aPTT of less than or equal to 50 seconds (odds ratio, 1.02; p = 0.013) and in patients with a decline in D-dimer less than or equal to 50% (odds ratio, 2.76; p = 0.041) the day after decannulation following adjustment for risk factors. CONCLUSIONS: The incidence of cannula-related venous thrombosis after venovenous extracorporeal membrane oxygenation is high. Reduced systemic anticoagulation may enhance the risk of thrombosis. Sustained elevation of D-dimer after decannulation may indicate thrombosis. Patients should undergo routine duplex sonography after extracorporeal membrane oxygenation to detect thrombosis formation in the cannulated vessel.

Quantitative assessment of peripheral limb perfusion using a modified distal arterial cannula in venoarterial ECMO settings.

In cases of severe cardiopulmonary deterioration, quick establishment of venoarterial extracorporeal membrane oxygenation (ECMO) represents a support modality. After successful arterial peripheral cannulation, a certain grade of peripheral limb malperfusion is a fairly common phenomenon. Detection of peripheral malperfusion is vital, since it can result in compartment syndrome or even loss of the affected limb. To prevent or resolve emerging lower limb ischaemia, a newly designed perfusion catheter is placed into the superficial femoral artery, distal to the arterial cannula via ECMO. The aim of our study was to evaluate flow and haemodynamic characteristics of this novel distal limb perfusion cannula for ECMO therapy and present these important findings for the first time. The distal perfusion cannula blood flow increases in linear correlation with ECMO blood flow The variability of distal perfusion cannula blood flow with a 15 Fr cannula ranges between 160 ± 0.40 mL min-1 at 1.5 L min-1 ECMO flow rate and 480 ± 80 mL min-1 at 5.0 L min-1 ECMO blood flow, respectively. Comparatively, the 17-Fr-sized cannula performs on a scale of 140 ± 20 to 390 ± 60 mL distal perfusion cannula blood flow at 1.5-5.0 L min-1 ECMO blood flow, respectively. The quantitative assessment of the distal perfusion cannula blood flow has revealed that distal perfusion cannula blood flow can measure up to 10% of the ECMO blood flow. Furthermore, it has been also well demonstrated that the novel distal perfusion cannula is sufficient to compensate peripheral limb ischaemia.

[Non-Elective Thoracic Surgery in Patients with Respiratory Insufficiency During Support with Veno-Venous Extracorporeal Membrane Oxygenation]. / Nicht elektive thoraxchirurgische Operationen bei Patienten mit respiratorischer Insuffizienz und Einsatz einer venovenösen extrakorporalen Membranoxygenierung.

INTRODUCTION: Patients with severe respiratory failure and veno-venous extracorporeal membrane oxygenation (vv-ECMO) often require diagnostic or therapeutic thoracic surgery. METHODS: Retrospective analysis of prospectively collected data (Regensburg ECMO Registry) on all patients requiring vv-ECMO between December 2010 and December 2016 due to acute lung failure (ALF) with diagnostic or therapeutic thoracic surgery. Endpoints were the indications for thoracic surgery as well as postoperative morbidity and in-hospital mortality. RESULTS: A total of 418 patients (male n = 285, 68%, mean age 50.0 ± 16.5 years) with severe respiratory insufficiency refractory to conventional therapy required vv-ECMO. Indications for vv-ECMO were ALF due to pneumonia (59.8%), postoperative (18.7%), posttraumatic (9.8%), after chemotherapy (2.8%) and others (8.9%). Overall, in 24.4% (n = 102) of patients with vv-ECMO surgery was performed. Of these, 28.4% (n = 29) of patients required thoracic surgery. Primary indications for thoracic surgery were most frequently therapeutic due to hemothorax (n = 13; 44.8%), followed by carnifying pneumonia/pulmonary abscess (n = 5; 17.2%), pleural empyema (n = 3; 10.3%) and others (n = 3; 10.3%). In patients with interstitial lung disease of unknown origin (n = 5; 17.2%), diagnostic pulmonary biopsy was performed. For initial thoracic intervention thoracotomy was carried out in 93.1% (n = 27) of patients, whereas only two patients (6.9%) received thoracoscopy. At least one repeated thoracotomy was performed in 15 patients (51.7%) and nine patients (31.0%) underwent more than two surgeries. In-hospital mortality of patients with thoracic surgery (44.8%) was higher than in patients without thoracic surgery (35.7%; p = 0.326). CONCLUSION: Thoracic surgery in patients with vv-ECMO warrants strict indications, because postoperative complications are common and surgical revision (58,6%) is often required. Therefore, ECMO therapy should only be carried out in specialised centers with thoracic surgery.

Long-Term Survival in Adult Patients With Severe Acute Lung Failure Receiving Veno-Venous Extracorporeal Membrane Oxygenation.

OBJECTIVES: To assess long-term survival in adult patients with severe acute lung failure receiving veno-venous extracorporeal membrane oxygenation and explore risk factors for long-term mortality. DESIGN: Single-center prospective cohort study. SETTING: University Hospital Regensburg, Germany. PATIENTS: All primary cases supported with veno-venous extracorporeal membrane oxygenation from 2007 to 2016 (n = 553). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Patients were followed until January 2017. Long-term survival and predictors of long-term mortality were assessed using Kaplan-Meier survival analyses and Cox proportional hazards modeling, respectively. Two hundred eighty-six patients (52%) died during follow-up (mean follow-up 4.8 yr). Two hundred seventeen patients (39%) died during hospitalization, whereas another 69 patients (12%) died during later follow-up. Among hospital survivors, the 1-month, 3-month, 1-year, and 5-year survival rates were 99%, 95%, 86%, and 76%, respectively. Higher age, immunocompromised status, and higher Sequential Organ Failure Assessment scores were associated with long-term mortality, whereas patients with out-of-center cannulation showed improved long-term survival. Due to nonproportional hazards over time, the analysis was repeated for hospital survivors only (n = 336). Only age and immunocompromised state remained significant predictors of late mortality among hospital survivors. Lower Glasgow Outcome Scale at hospital discharge and the University Hospital Regensburg pre-extracorporeal membrane oxygenation score for predicting hospital mortality in veno-venous extracorporeal membrane oxygenation patients before extracorporeal membrane oxygenation initiation were associated with late mortality in hospital survivors (p < 0.001). CONCLUSIONS: Whereas acute illness factors may be important in prediction of hospital outcomes in veno-venous extracorporeal membrane oxygenation patients, they do not determine late mortality in hospital survivors. Preexisting morbidity and functional ability at hospital discharge may be important determinants of long-term survival in veno-venous extracorporeal membrane oxygenation patients.

Hemostatic Changes During Extracorporeal Membrane Oxygenation: A Prospective Randomized Clinical Trial Comparing Three Different Extracorporeal Membrane Oxygenation Systems.

OBJECTIVE: Extracorporeal membrane oxygenation is a rescue therapy for patients with severe lung failure. Major complications caused by extracorporeal membrane oxygenation are bleeding, thrombosis, and hemolysis. The aim of this study was to compare the impact of different extracorporeal membrane oxygenation systems on blood hemostasis in adults during veno-venous extracorporeal membrane oxygenation therapy. DESIGN: Single center prospective randomized study. SETTING: University Hospital Regensburg, Germany. PATIENTS: Adult patients with severe acute respiratory distress syndrome requiring veno-venous extracorporeal membrane oxygenation therapy. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Three different extracorporeal membrane oxygenation systems: the Cardiohelp system (Maquet Cardiopulmonary AG), the Dideco ECC.O5 (Sorin Group), and the Deltastream system with Hilite 7000 LT + DP3 pumphead (Medos Medizintechnik AG) were compared. Therefore hemostasis, anticoagulation, hemolysis, and inflammatory parameters were monitored. Of the 54 patients included in the study, 18 patients each were randomly assigned to the three different extracorporeal membrane oxygenation systems. Exclusion criteria were acute renal failure, trauma, and surgery within 2 days. The median time on veno-venous extracorporeal membrane oxygenation support was 13.5 days (4-70 d). Median platelet count had dropped from 220.5 G/L before extracorporeal membrane oxygenation therapy to a minimum of 133 G/L by the last day of extracorporeal membrane oxygenation support. During the first 5 days of extracorporeal membrane oxygenation therapy, prothrombin fragment 1.2 (F1.2) (1.36-2.4 µM), thrombin-antithrombin complex (14.5-50 µg/L), and D-dimers (6.00-27.0 mg/L) increased, whereas fibrinogen values dropped from 5.8 to 4.1 g/L. The three different extracorporeal membrane oxygenation systems did not show any differences with regard to hemostasis, anticoagulation, hemolysis, and inflammatory parameters within the first 5 days of extracorporeal membrane oxygenation therapy. CONCLUSIONS: Over time, miniaturized veno-venous extracorporeal membrane oxygenation therapy increasingly activates coagulation. The different types of membrane oxygenators and pumps did not significantly alter hemostasis.