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Cardiopulmonary bypass (CPB) circuits can significantly sequester intravenous anesthetics. Adsorption of medications by our institution's standard circuit (Terumo CAPIOX FX05 oxygenator; noncoated polyvinylchloride tubing) has not been described. We prepared ex vivo CPB circuits with and without oxygenators. Medication combinations studied included midazolam (0.5 mg), fentanyl (50 [micro]g), midazolam (0.5 mg) with morphine (0.5 mg), and midazolam (0.5 mg) with fentanyl (50 [micro]g). Medications were administered after obtaining baseline samples. Samples were drawn at 2, 5, 15, 30, 60, 120, and 180 minutes, and analyzed for concentration of injected medications. Midazolam demonstrated no sequestration after 180 minutes. Fentanyl concentration at 180 minutes was lower with an oxygenator (52.7 +/- 12.5 vs. 110.9 +/- 12.0 ng/ml, P = 0.00432). More fentanyl was found in solution after 180 minutes when given with midazolam compared to fentanyl given alone in the presence of an oxygenator (101 +/- 22.3 vs. 52.7 +/- 12.5 ng/ml, P = 0.044). Less midazolam was present after 180 minutes when given with morphine compared to midazolam given alone in the absence of an oxygenator (1264.9 +/- 425.6 vs. 2124 +/- 254 ng/ml, P = 0.037). We successfully characterized the adsorption of various combinations of midazolam, fentanyl, and morphine to our CPB circuit, showing that fentanyl and midazolam behave differently based on other medications present.

Objectives To determine the oxygenator impact on alterations of ceftolozane/tazobactam in a contemporary neonatal/pediatric (1/4-inch) and adolescent/adult (3/8-inch) extracorporeal membrane oxygenation circuit including the Quadrox-i oxygenator (Maquet, Wayne, NJ). Design A 1/4-inch and 3/8-inch, simulated closed-loop extracorporeal membrane oxygenation circuits were prepared with a Quadrox-i pediatric and Quadrox-i adult oxygenator and blood primed. Additionally, 1/4-inch and 3/8-inch circuits were also prepared without an oxygenator in series. A one-time dose of ceftolozane/tazobactam was administered into the circuits and serial preoxygenator and postoxygenator concentrations were obtained at 5 minutes, 1, 2, 3, 4, 5, 6, and 24-hour time points. Ceftolozane/tazobactam was also maintained in a glass vial and samples were taken from the vial at the same time periods for control purposes to assess for spontaneous drug degradation SETTING:: A free-standing extracorporeal membrane oxygenation circuit. Patients None. Interventions Single-dose administration of ceftolozane/tazobactam into closed-loop extracorporeal membrane oxygenation circuits prepared with and without an oxygenator in series with serial preoxygenator, postoxygenator, and reference samples obtained for concentration determination over a 24-hour study period. Measurements and main results For the 1/4-inch circuit, there was approximately 92% ceftolozane and 22-25% tazobactam loss with the oxygenator in series and 19-30% ceftolozane and 31-34% tazobactam loss without an oxygenator in series at 24 hours. For the 3/8-inch circuit, there was approximately 85% ceftolozane and 29% tazobactam loss with the oxygenator in series and 25-27% ceftolozane and 23-26% tazobactam loss without an oxygenator in series at 24 hours. The reference ceftolozane and tazobactam concentrations remained relatively constant during the entire study period demonstrating the drug loss in each size of the extracorporeal membrane oxygenation circuit with or without an oxygenator was not a result of spontaneous drug degradation. Conclusions This ex vivo investigation demonstrated substantial ceftolozane loss within an extracorporeal membrane oxygenation circuit with an oxygenator in series with both sizes of the Quadrox-i oxygenator at 24 hours and significant ceftolozane loss in the absence of an oxygenator. Tazobactam loss was similar regardless of the presence of an oxygenator. Further evaluations with multiple dose in vitro and in vivo investigations are needed before specific drug dosing recommendations can be made for clinical application with extracorporeal membrane oxygenation.

Background: Cardiac surgery using cardiopulmonary bypass carries a high risk of bleeding and need for blood transfusion. Blood administration is associated with increased rates of morbidity and mortality. Perioperatively, strategies are often employed to reduce blood transfusions in high-risk patients or in situations where blood transfusion is contraindicated. Normovolemic hemodilution is a blood conservation technique used during cardiac surgery that involves replacement of blood with fluids. SANGUINATE® (PEGylated carboxyhemoglobin bovine) is a novel hemoglobin-based oxygen carrier that can deliver oxygen effectively to tissues in the presence of severe hypoxia. The use of a hemoglobin-based oxygen carrier during hemodilution may augment tissue oxygen delivery and reduce blood transfusion. Methods: Six standardized cardiopulmonary bypass runs simulating normovolemic hemodilution using varying proportions of bovine whole blood and SANGUINATE were performed. Pump speed, flow rate, line pressures, hemoglobin concentration, oxygenation, and degree of anticoagulation were assessed at regular intervals. Membrane oxygenators and arterial line filters were inspected for evidence of clotting following each run. Results: Increases in the pressure drop across the membrane oxygenator were detected during runs 5 and 6. Median activated clotting time values were able to be maintained at goal during the runs, and SANGUINATE did not appear to be thrombogenic. Hemoglobin concentration decreased following the addition of SANGUINATE. Oxygenation was maintained during all runs that included SANGUINATE. Conclusion: SANGUINATE does not impact the performance of the cardiopulmonary bypass circuit in a bovine whole blood model. The results support further evaluation of SANGUINATE in the setting of normovolemic hemodilution and cardiopulmonary bypass.

Objective: Patients on extracorporeal membrane oxygenation are frequently in need for sedation. Use of propofol has been associated with impaired oxygenator function due to adsorption to the membrane as well as lipid load. The aim of our retrospective analysis was to compare two different sedation regimens containing either propofol or midazolam with respect to oxygenator running time. Methods: Midazolam was used in 73 patients whereas propofol was used in 49 patients, respectively. In the propofol group, veno-arterial–extracorporeal membrane oxygenation was used predominantly (84%), while veno-venous–extracorporeal membrane oxygenation was used more often in the midazolam group (64%). Results: Oxygenator running time until first exchange was 7 days in both groups ( p = 0.759). No statistically significant differences could be observed between the subgroup of patients receiving lipid-free (n = 24) and lipid-containing (n = 31) parenteral nutrition, respectively. Laboratory parameters like triglycerides, free hemoglobin, fibrinogen, platelets, and activated partial thromboplastin time were not significantly different between both sedation regimens ( p = 0.462, p = 0.489, p = 0.960, p = 0.134, and p = 0.843) and were not associated with oxygenator running time. Conclusion: The use of propofol as sedative seems suitable in patients undergoing extracorporeal membrane oxygenation therapy.

Background Extracorporeal membrane oxygenation (ECMO) research using large animals requires a significant amount of resources, slowing down the development of new means of ECMO anticoagulation. Therefore, this study developed and evaluated a new rat ECMO model using a 3D-printed mock-oxygenator. Methods The circuit consisted of tubing, a 3D-printed mock-oxygenator, and a roller pump. The mock-oxygenator was designed to simulate the geometry and blood flow patterns of the fiber bundle in full-scale oxygenators but with a low (2.5 mL) priming volume. Rats were placed on arteriovenous ECMO at a 1.9 mL/min flow rate at two different heparin doses (n = 3 each): low (15 IU/kg/h for eight hours) versus high (50 IU/kg/h for one hour followed by 25 IU/kg/h for seven hours). The experiment continued for eight hours or until the mock-oxygenator failed. The mock-oxygenator was considered to have failed when its blood flow resistance reached three times its baseline resistance. Results During ECMO, rats maintained near-normal mean arterial pressure and arterial blood gases with minimal hemodilution. The mock-oxygenator thrombus weight was significantly different (p Conclusions This model is a simple, inexpensive system for investigating new anticoagulation agents for ECMO and provides low and high levels of anticoagulation that can serve as control groups for future studies.

The importance of microbial colonization during extracorporeal membrane oxygenation (ECMO) is unclear. We prospectively cultured ECMO oxygenators and retrospectively reviewed the culture results, clinical outcomes, and associated factors in 112 ECMO patients (122 oxygenators, 1,196 ECMO days). Of the oxygenators, 11.6% (n = 13) had positive cultures. The most common pathogen was Klebsiella pneumoniae, followed by Acinetobacter baumannii and Staphylococcus epidermidis. Nine (69%) cases showed catheter colonization, and five (38%) bloodstream infection (BSI) with the same microorganism. Most of the microorganisms were multidrug resistant. BSI tended to be associated with oxygenator colonization (r = 0.172, p = 0.070). The patients were divided into oxygenator colonization (n = 13) and no colonization groups (n = 99). Successful weaning from ECMO and survival to discharge were significantly lower in the oxygenator colonization group (weaning 30.8% vs. 90.9%, p < 0.001, survival 23.1% vs. 76.8%; p < 0.001). In multivariate analyses, age (per decade) (odds ratio [OR] = 1.95, 95% CI = 1.28-2.95; p = 0.002), oxygenator colonization (OR = 15.49, 95% CI = 3.31-72.46; p < 0.001), and renal replacement therapy (OR = 4.61, 95% CI = 1.69-12.58; p = 0.003) were significantly associated with mortality. Oxygenator colonization was associated with poor outcomes in ECMO patients. These results support the early exchange and culture of oxygenators in patients with persisting bacteremia.

KEY POINTS The margin of human viability has extended to the extremes of gestational age (

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) is a form of cardiopulmonary life support frequently utilized in catastrophic lung and or cardiac failure. Patients on ECMO often receive vancomycin therapy for treatment or prophylaxis against Gram-positive organisms. It is unclear if ECMO affects vancomycin pharmacokinetics, thus we modeled the pharmacokinetic behavior of vancomycin according to ECMO-specific variables. METHODS: Adult patients receiving vancomycin and Veno-Arterial-ECMO between 12/1/2016 and 10/1/2017 were prospectively enrolled. Extracorporeal membrane oxygenation settings and four sets of pre- and post-oxygenator vancomycin concentrations were collected for each patient. Compartmental models were built and assessed ECMO flow rates on vancomycin clearance and potential circuit sequestration. Bayesian posterior concentrations of the pre- and post-oxygenator concentrations were obtained for each patient, and summary pharmacokinetic parameters were calculated. Simulations were performed from the final model for efficacy and toxicity predictions. RESULTS: Eight patients contributed 64 serum concentrations. Patients were a median (interquartile range) age of 58.5 years (50.8–62.3) with a calculated creatinine clearance of 39 mL/min (29.5–62.5) and ECMO flow rates of 3980 mL/min (interquartile range = 3493.75–4132.5). A three-compartment model best fit the data (Bayesian: plasma pre-oxygenation R(2) = 0.99, post-oxygenation R(2) = 0.99). Vancomycin clearance was not impacted by ECMO flow rate (p = 0.7). Simulations demonstrated that vancomycin 1 g twice daily was rarely sufficient for minimum inhibitory concentrations > 0.5 mg/L. Doses ≥ 1.5 g twice daily often exceeded toxicity thresholds for exposure. CONCLUSIONS: Extracorporeal membrane oxygenation flow rates did not influence vancomycin clearance between flow rates of 3500 and 5000 mL/min and vancomycin was not sequestered in ECMO. Common vancomycin regimens resulted in sub-optimal efficacy and/or excessive toxicity. Individual therapeutic drug monitoring is recommended for patients on ECMO.

Purpose Volatile anesthetics (VAs) protect myocardial cells in cardiovascular surgery. A recent clinical trial of cardiopulmonary bypass (CPB) surgery reported no significant difference in mortality rates between the use of VAs and total intravenous anesthetics at 1 year postoperatively. However, oxygenator function may affect the VA pharmacokinetics. Thus, we measured the VA blood concentrations during CPB in patients managed with four different microporous polypropylene hollow fiber membrane oxygenators. Methods Twenty-four patients scheduled for elective CPB were randomly allocated to one of the two VA groups (desflurane and sevoflurane groups) and, then, randomly divided into one of four oxygenator groups: Terumo, LivaNova, Medtronic, and Senko (n = 3). Additionally, in each VA group, three patients were randomly selected and redundantly allocated to the human lung group (for control blood VA concentration without oxygenator). Blood samples collected 20 min after starting 6.0 vol% desflurane or 1.7 vol% sevoflurane were analyzed using gas chromatography. Oxygenator-related complications and structural changes in the membrane surface of each oxygenator after surgery were evaluated. Results The mean (standard deviation) concentrations of desflurane and sevoflurane in the human lung were 182.4 (23.2) and 54.0 (9.6) μg/ml, respectively; not significantly different from those in the four oxygenator groups. No oxygenator-related complications occurred. Structural changes in membrane fibers did not occur after clinical use, except for difficulty in image acquisition with Senko products. Conclusion Our results demonstrated that the blood concentrations of desflurane and sevoflurane passing through oxygenators used during CPB were similar to those in the human lung control. Electronic supplementary material The online version of this article (10.1007/s00540-020-02844-1) contains supplementary material, which is available to authorized users.

Our objective was to assess the effect of nitric oxide added to the sweep gas of the oxygenator during cardiopulmonary bypass (CPB) in infants on platelet count, platelet function, clinical outcomes, and safety. A randomized, double-blinded, placebo-controlled clinical trial in infants less than a year of age undergoing cardiac surgery requiring CPB was undertaken. Nitric oxide at a dose of 20 ppm was added to the sweep gas in the treatment group. Blood was collected at baseline and prior to separation from CPB to measure platelet count and function as determined by responsiveness to specific agonists. Clinical outcomes were observed through hospital discharge. Methemoglobin levels were measured preoperatively, at the conclusion of CPB, and upon admission to the ICU. Forty patients consented and were randomized in the trial. Eighteen patients were randomized to the treatment group and 22 were included in the placebo group. The groups were similar in terms of age, weight, gender, and surgical complexity. No significant differences were found in measures of platelet count, platelet response to agonist, or clinical outcomes. Patients in the treatment group had higher methemoglobin levels after receiving nitric oxide, but no levels approached toxicity (maximum 2.4%). Nitric oxide added to the sweep gas of the oxygenator during CPB in infants did not have an appreciable effect on the preservation of platelet count, platelet responsiveness to agonist, or clinical outcomes. Methemoglobin levels were increased after receiving nitric oxide but were far below a toxic level of 15%.

To determine the oxygenator impact on alterations of ceftaroline in a contemporary neonatal/pediatric (1/4-inch) and adolescent/adult (3/8-inch) extracorporeal membrane oxygenation circuit including the Quadrox-i oxygenator (Maquet, Wayne, NJ).Quarter-inch and 3/8-inch, simulated closed-loop extracorporeal membrane oxygenation circuits were prepared with a Quadrox-i pediatric and Quadrox-i adult oxygenator and blood primed. Additionally, 1/4-inch and 3/8-inch circuits were also prepared without an oxygenator in series. An one-time dose of ceftaroline was administered into the circuits, and serial pre- and postoxygenator concentrations were obtained at 5 minutes, 1-, 2-, 3-, 4-, 5-, 6-, and 24-hour time points. Ceftaroline was also maintained in a glass vial, and samples were taken from the vial at the same time periods for control purposes to assess for spontaneous drug degradation.A free-standing extracorporeal membrane oxygenation circuit.None.Single dose administration of ceftaroline into closed-loop extracorporeal membrane oxygenation circuits prepared with and without an oxygenator in series with serial preoxygenator, postoxygenator, and reference samples obtained for concentration determination over a 24-hour study period.For the 1/4-inch circuit with an oxygenator, there was 79.8% drug loss preoxygenator and 82.5% drug loss postoxygenator at 24 hours. There was a statistically significant difference (p0.01) in the amount of ceftaroline remaining at 24 hours when compared with each prior time point for the 1/4-inch circuit. For the 1/4-inch circuit without an oxygenator, there was no significant drug loss at any study time point. For the 3/8-inch circuit with an oxygenator, there was 76.2% drug loss preoxygenator and 77.6% drug loss postoxygenator at 24 hours. There was a statistically significant difference (p0.01) in the amount of ceftaroline remaining at 24 hours when compared with each prior time point for the 3/8-inch circuit. For the 3/8-inch circuit without an oxygenator, there was no significant drug loss at any study time point. The reference ceftaroline concentrations remained relatively constant during the entire study period demonstrating the ceftaroline loss in each size of the extracorporeal membrane oxygenation circuit with or without an oxygenator was not a result of spontaneous drug degradation and primarily the result of the oxygenator.This ex vivo investigation demonstrated significant ceftaroline loss within an extracorporeal membrane oxygenation circuit with an oxygenator in series with both sizes of the Quadrox-i oxygenator at 24 hours. Therapeutic concentrations of ceftaroline in the setting of extracorporeal membrane oxygenation may not be achieved with current U.S. Food and Drug Administration-recommended doses, and further evaluation is needed before specific drug dosing recommendations can be made for clinical application with extracorporeal membrane oxygenation.

Extracorporeal membrane oxygenation (ECMO) is one of the most frequent forms of extracorporeal life support (ECLS) and can be used as rescue therapy in patients with severe respiratory failure resulting from burns and/or smoke inhalation injury. Experience and literature on this treatment option is still very limited, consequently results are varied. We report a retrospective analysis of our experience with veno-venous (VV) ECMO in burn patients. All five patients, three male and two female (age: 28-37 years) had flame type burns and smoke inhalation injury. Their Murray scores ranged between 3.25 and 3.75, and their revised Baux scores between 62 and 102. The mean pre-ECMO conventional ventilation time was 7.4days (3-13). The mean ECMO duration was 18days (8-35). Three patients were cannulated with dual lumen, two with separate cannulae. One oxygenator had to be changed due to technical issues and two patients needed two parallel oxygenators. Four patients had renal replacement therapy. All patients needed vasoconstrictor support, antibiotics and packed red blood cells (5-62 units). Three had steroid treatment. All five patients were successfully weaned from ECMO. One patient died later from multi-organ failure in the ICU, the other four patients survived. VV-ECMO is a useful rescue intervention in patients with burns related severe respiratory failure. Patients in our institution benefit from having both burns and ECMO centres with major expertise in the field under one roof. The results from this small cohort are encouraging, although more cases are needed to draw more robust conclusions.

Annals of thoracic and cardiovascular surgery 24(5), 230-237 (2018). doi:10.5761/atcs.oa.18-00019, Published by Medical Tribune, Tokyo

Introduction The recommended minimum activated clotting time (ACT) level for cardiopulmonary bypass (CPB) of 480 seconds originated from investigations with bubble oxygenators and uncoated extracorporeal circulation (ECC) systems. Modern minimal invasive ECC (MiECC) systems are completely closed circuits containing a membrane oxygenator and a tip-to-tip surface coating. We hypothesized that surface coating and the “closed-loop” design allow the MiECC to safely run with lower ACT levels and that an ACT level of 300 seconds can be safely applied without thromboembolic complications. The aim of this study was to investigate the potential risks during application of reduced heparin levels in patients undergoing coronary surgery. Methods In this study, 68 patients undergoing coronary artery bypass grafting with MiECC were randomized to either the study group with an ACT target of 300 seconds or the control group with an ACT of 450 seconds. All other factors of MiECC remained unchanged. Results The study group received significantly less heparin and protamine (heparin [international units] median [min–max], Red_AC: 32,800 [23,000–51,500] vs. Full_AC: 50,000 [35,000–65,000] p Conclusion Since no evidence of increased thrombin formation (ETP) was found from a laboratory standpoint, we concluded that the use of MiECC with a reduced anticoagulation strategy seems possible. This alternative anticoagulation strategy leads to significant reduction in dosages of both heparin and protamine. We can confidently move forward with investigating this anticoagulation concept. However, to establish clinical safety of ACT below 300 seconds, we need larger clinical studies.

The objective of this study was to compare the hemodynamic performances and gaseous microemboli (GME) handling ability of two pediatric oxygenators in a simulated pediatric cardiopulmonary bypass (CPB) model and the importance of adding an arterial filter in the circuit. The circuit consisted of a Braile Infant oxygenator or a Maquet Quadrox-I Pediatric oxygenator without integrated arterial filter (parallel arrangement), 1/4 in. ID tubing A-V loop, and a 12-Fr arterial cannula, primed with lactated Ringer's solution and packed red blood cells. Trials were conducted at flow rates ranging from 500 to 2000 mL/min (500 mL/min increment) at 35°C and 28°C. Real-time pressure and flow data were recorded using a custom-based data acquisition system. For GME testing, 5 cc of air was manually injected into the venous line. GME were recorded using the Emboli Detection and Classification Quantifier (EDAC) System. An additional experiment using a separate arterial filter was conducted. There was no difference in the mean circuit pressure, pressure drop, total hemodynamic energy level, and energy loss between the two oxygenators. The venous line pressures were higher in the Braile than in the Quadrox group during all trials (P

Neurologic complications during neonatal extracorporeal life support (ECLS) are associated with significant morbidity and mortality. Gaseous microemboli (GME) in the ECLS circuit may be a possible cause. Advances in neonatal circuitry may improve hemodynamic performance and GME handling leading to reduction in patient complications. This study compared hemodynamic performance and GME handling using two centrifugal pumps (Maquet RotaFlow and Medos Deltastream DP3) and polymethylpentene oxygenators (Maquet Quadrox-iD and Medos Hilite 800LT) in a neonatal ECLS circuit model. The experimental circuit was primed with Lactated Ringer's solution and packed human red blood cells (hematocrit 40%) and arranged in parallel with the RotaFlow and DP3 pump, Quadrox-iD and Hilite oxygenator, and Better-Bladder. Hemodynamic trials evaluating pressure drops and total hemodynamic energy (THE) were conducted at 300 and 500 mL/min at 36°C. GME handling was measured after 0.5 mL of air was injected into the venous line using the Emboli Detection and Classification Quantifier System with unique pump, oxygenator, and Better-Bladder combinations. The RotaFlow pump and Quadrox oxygenator arrangement had lower pressure drops and THE loss at both flow rates compared to the DP3 pump and Hilite oxygenator (P < 0.01). Total GME volume and counts decreased with Better-Bladder at both flow rates with all combinations (P < 0.01). Hemodynamic performance and energy loss were similar in all of the circuit combinations. The Better-Bladder significantly decreased GME. All four combinations of pumps and oxygenators also performed similarly in terms of GME handling.

Purpose We assessed the security and efficiency of intravenously injected agitated saline in conjunction with transthoracic echocardiography to identify recirculation in patients supported with a venovenous extracorporeal membrane oxygenation (VV ECMO) device. Materials and Methods We injected agitated saline 4 consecutive times separated by an interval of 5 minutes in 2 patients supported by VV ECMO. In both patients, the drainage cannula was placed in the left femoral vein, and the return cannula was placed in the right internal jugular vein. Echocardiography was performed during the injection and until the bubbles disappeared. The security of the method was assessed by evaluating the mechanical function of the ECMO and the efficiency of the oxygenator. The value of this method was assessed by visualizing the increase of inferior vena cava's echogenicity as well as by measuring the time required for this change to occur after the injection of agitated saline at different ECMO output levels. Results We did not observe any change in ECMO, oxygenation function, or the hemodynamic status of patients after the 4 injections of agitated saline. The echogenicity of the inferior vena cava increased more rapidly as the ECMO's output increased. The recirculation phenomenon was noted even with low levels of ECMO output ( Conclusions Transthoracic echocardiography in conjunction with agitated saline administration may be a safe and easily applicable method to evaluate a recirculation phenomenon in patients supported with VV ECMO.

Although the innovation has come in ECMO field, many problems remain unresolved. One of the main problems is about long-term durability and biocompatibility. Another is the system’s size, weight, and its complicated equipment. For the former problem, we have previously developed ECMO system which consists of a tiny, hydrodynamically levitated centrifugal pump (BIOFLOAT-NCVC), a membrane oxygenator with hollow polyolefin fibers (BIOCUBE-NCVC), and the circuit treated with a heparin-bonding material (T-NCVC coating), and reported three cases of animal experiments for 30-day heparin-free drive. For the latter problem, we have integrated these elements to the compact system with sensors of temperature, pressure, and SvO2, and blood flow. Its installation area is 595 cm2, weighs 8.9 kg with attachable oxygen cassette, and battery which could last an hour at least. To evaluate the biocompatibility of this system, this ECMO was installed in four goats. Scheduled duration was 14 days. Heparin was continuously infused to control their ACT between 150 and 200 s except one 2-week experiment without systemic heparinization. All of the four goats survived till the scheduled termination. Function of the pump and the oxygenator during ECMO was stable. No obvious adverse events were observed. All lab data were of normal range after 1 week. Small infarctions were found at kidneys, but they were not clinically significant. No thrombus was found in the pump system. The oxygenators were extremely clean except a little thrombus formation; while, the heparin-free examination revealed acceptable cleanliness. The present study revealed good anti-thrombogenicity of this ultra-compact durable ECMO system with heparinization. Our system encourages awake and extubated management, rehabilitation, inter-hospital transfer, and prehospital initiation of ECMO.

Coagulopathy and bleeding is a frequent phenomenon in patients on extracorporeal membrane oxygenation. The cause may be multifactorial and it may change over time. We present a case when bleeding was caused by hyperfibrinolysis induced by oxygenator. The diagnosis was established by comparing thromboelastometry result from blood obtained before and after oxygenator. Hyperfibrinolysis and bleeding could be successfully treated merely by oxygenator exchange.

Background: Oxidative stress-induced lipid peroxidation (LPO) due to neutrophil-derived reactive oxygen species plays a key role in the early stage of the acute respiratory distress syndrome (ARDS). Monitoring of oxidative stress in this patient population is of great interest, and, ideally, this can be done noninvasively. Recently, propionaldehyde, a volatile chemical compound (VOC) released during LPO, was identified in the breath of lung transplant recipients as a marker of oxidative stress. The aim of the present study was to identify if markers of oxidative stress appear in the oxygenator outflow gas of patients with severe ARDS treated with veno-venous extracorporeal membrane oxygenation (ECMO). Methods: The present study included patients with severe ARDS treated with veno-venous ECMO. Concentrations of acetone, isoprene, and propionaldehyde were measured in inspiratory air, exhaled breath, and oxygenator inflow and outflow gas at corresponding time points. Ion-molecule reaction mass spectrometry was used to measure VOCs in a sequential order within the first 24 h and on day three after ECMO initiation. Results: Nine patients (5 female, 4 male, age = 42.1 &plusmn, 12.2 year) with ARDS and already established ECMO therapy (pre-ECMO PaO2/FiO2 = 44.0 &plusmn, 11.5 mmHg) were included into analysis. VOCs appeared in comparable amounts in breath and oxygenator outflow gas (acetone: 838 (422&ndash, 7632) vs. 1114 (501&ndash, 4916) ppbv, isoprene: 53.7 (19.5&ndash, 244) vs. 48.7 (37.9&ndash, 108) ppbv, propionaldehyde: 53.7 (32.1&ndash, 82.2) vs. 42.9 (24.8&ndash, 122) ppbv). Concentrations of acetone, isoprene, and propionaldehyde in breath and oxygenator outflow gas showed a parallel course with time. Conclusions: Acetone, isoprene, and propionaldehyde appear in breath and oxygenator outflow gas in comparable amounts. This allows for the measurement of these VOCs in a critically ill patient population via the ECMO oxygenator outflow gas without the need of ventilator circuit manipulation.

INTRODUCTION: A patient on VV ECMO for COVID ARDS survived a prolonged ECMO course and refractory acidosis with double oxygenator support METHODS: A 32-year-old previously healthy Latino male presented with cough, fever, myalgias and dyspnea and was positive for COVID-19 He was admitted on high flow oxygen but required mechanical ventilation on Hospital Day (HD)6 He developed oliguric renal failure and progressed to severe ARDS requiring paralytic, proning and PEEP of 16 He was cannulated for VV ECMO on HD9 for refractory acidosis and hypoxia Murray score was >3, P:F ratio was 60 Despite ECMO and continuous dialysis, the patient remained acidotic and was reliant on supplemental ventilator support, ongoing paralytic and heavy sedation He developed a pneumothorax due to barotrauma and had multiple chest tubes for poor re-expansion Due to maximum sweep support, an additional oxygenator was added on HD19 The patient had a prolonged recovery with complications of transfusion dependent epistaxis requiring ENT packing and hematochezia requiring rectal and IMA embolization After significant transfusion he developed acute right ventricular dysfunction which was supported with inotropy and inhaled nitric oxide and later developed sepsis from bacteremia as well He was finally stable for tracheostomy on HD61 and was decannulated from ECMO on HD66 He has since had cardiac and renal recovery and is weaning from vent support RESULTS: ECMO has been used as rescue therapy in COVID ARDS but multi-center studies report mortality rates of 50% to as high as 94%- much higher when compared to MERS or H1NI viral ARDS support Life threatening complications of bleeding, thrombosis, infection and refractory cardiopulmonary failure are common but COVID ARDS presents new physiologic challenges that are not yet well understood As of July 27 2020, of a cohort of 148 ECMO supported COVID patients in the SpecialtyCare national perfusion database, the average support duration is 16 days (SD 14 days) Our patient required 57 days on ECMO and is the only patient to have survived double oxygenator support in our database His case supports future use of additional oxygenators in refractory acidosis, which may be more common in COVID physiology He also reminds us that prolonged COVID ARDS recovery is possible

To compare intraoperative cerebral microembolic load between minimally invasive extracorporeal circulation (MiECC) and conventional extracorporeal circulation (CECC) during isolated surgical aortic valve replacement (SAVR), we conducted a randomized trial in patients undergoing primary elective SAVR at a tertiary referral hospital. The primary outcome was the procedural phase-related rate of high-intensity transient signals (HITS) on transcranial Doppler ultrasound. HITS rate was used as a surrogate of cerebral microembolism in pre-defined procedural phases in SAVR using MiECC or CECC with (+F) or without (-F) an oxygenator with integrated arterial filter. Forty-eight patients were randomized in a 1:1 ratio to MiECC or CECC. Due to intraprocedural Doppler signal loss (n = 3), 45 patients were included in final analysis. MiECC perfusion regimen showed a significantly increased HITS rate compared to CECC (by a factor of 1.75; 95% confidence interval, 1.19-2.56). This was due to different HITS rates in procedural phases from aortic cross-clamping until declamping [phase 4] (P = 0.01), and from aortic declamping until stop of extracorporeal perfusion [phase 5] (P = 0.05). Post hoc analysis revealed that MiECC-F generated a higher HITS rate than CECC+F (P = 0.005), CECC-F (P = 0.05) in phase 4, and CECC-F (P = 0.03) in phase 5, respectively. In open-heart surgery, MiECC is not superior to CECC with regard to gaseous cerebral microembolism. When using MiECC for SAVR, the use of oxygenators with integrated arterial line filter appears highly advisable. Only with this precaution, MiECC confers a cerebral microembolic load comparable to CECC during this type of open heart surgery.

Bozok, Sahin/0000-0002-1256-5055; Musabak, Ugur/0000-0003-1511-7634; Sargon, Mustafa Fevzi/0000-0001-6360-6008 WOS: 000384800700018 PubMed: 27841912 Aim: To investigate and compare uncoated and phosphoryl-choline-coated oxygenators in terms of induction of humoral immune response during coronary artery bypass surgery. Methods: A total of 20 consecutive patients who underwent coronary artery bypass surgery were randomly distributed into two groups according to the type of oxygenator used during surgery. Group 1 consisted of 10 patients who were operated on using phosphorylcholine-coated oxygenators. Group 2 contained 10 patients who underwent surgery using uncoated oxygenators. Blood and oxygenator fibre samples were obtained and compared in terms of immunoglobulins (IgG, IgM), complements (C3c, C4), serum total protein and albumin levels using electron microscopy and flow cytometry. Results: in group 1, levels of IgM, IgG, total protein and serum albumin were significantly increased at the end of cardiopulmonary bypass (CPB) compared to those at the beginning of CPB. in group 2, C3c and C4 levels at the beginning of CPB were found to be significantly higher than at the end. Electron microscopic examination of oxygenator fibres demonstrated that phosphorylcholine-coated fibres were less likely to be adsorbed by serum proteins and complements than the uncoated fibres. Conclusion: Our results indicate that phosphorylcholine-coated oxygenators seemed to induce humoral immune response to a lesser extent than uncoated oxygenators during coronary artery bypass procedures.