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CONTEXT: Clinical adoption of ex situ liver perfusion is growing. While hypothermic perfusion protects against ischemia-reperfusion injury in marginal grafts, normothermic perfusion enables organ viability assessment and therefore selection of borderline grafts. The combination of hypothermic and normothermic perfusion, known as "cold-to-warm," may be the optimal sequence for organ preservation, but is difficult to achieve with most commercial perfusion systems. We developed an adaptable customized circuit allowing uninterrupted "cold-to-warm" perfusion and conducted preclinical studies on healthy porcine livers and discarded human livers to demonstrate the circuit's efficacy. METHODS: In collaboration with bioengineers, we developed a customized circuit that adapts to extracorporeal circulation consoles used in cardiovascular surgery and includes a proprietary reservoir enabling easy perfusate change without interrupting perfusion. This preclinical study was conducted on porcine and human livers. Perfusion parameters (pressures, flows, oxygenation) and organ viability were monitored. RESULTS: The customized circuit was adapted to a LivaNova S5® console, and the perfusions were flow-driven with real-time pressure monitoring. Ten porcine liver and 12 discarded human liver perfusions were performed during 14 to 18 h and 7 to 25 h, respectively. No hyperpressure was observed (porcine and human portal pressure 2-6 and 2-8 mm Hg; arterial pressure 10-65 and 20-65 mm Hg, respectively). No severe histological tissue injury was observed (Suzuki score ≤ 3 at the end of perfusion). Seven (70%) porcine livers and five (42%) human livers met the UK viability criteria. CONCLUSION: The customized circuit and system design enables smooth uninterrupted "cold-to-warm" perfusion not present in current commercial perfusion systems.
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Hígado , Preservación de Órganos , Perfusión , Animales , Hígado/irrigación sanguínea , Porcinos , Preservación de Órganos/métodos , Preservación de Órganos/instrumentación , Humanos , Perfusión/métodos , Perfusión/instrumentación , Trasplante de Hígado/métodos , Circulación Extracorporea/instrumentación , Circulación Extracorporea/métodos , Diseño de EquipoRESUMEN
Disturbed oxygenation is foremost the leading clinical presentation in COVID-19 patients. However, a small proportion also develop carbon dioxide removal problems. The Advanced Organ Support (ADVOS) therapy (ADVITOS GmbH, Munich, Germany) uses a less invasive approach by combining extracorporeal CO2 -removal and multiple organ support for the liver and the kidneys in a single hemodialysis device. The aim of our study is to evaluate the ADVOS system as treatment option in-COVID-19 patients with multi-organ failure and carbon dioxide removal problems. COVID-19 patients suffering from severe respiratory insufficiency, receiving at least two treatments with the ADVOS multi system (ADVITOS GmbH, Munich, Germany), were eligible for study inclusion. Briefly, these included patients with acute kidney injury (AKI) according to KDIGO guidelines, and moderate or severe ARDS according to the Berlin definition, who were on invasive mechanical ventilation for more than 72 hours. In total, nine COVID-19 patients (137 ADVOS treatment sessions with a median of 10 treatments per patient) with moderate to severe ARDS and carbon dioxide removal problems were analyzed. During the ADVOS treatments, a rapid correction of acid-base balance and a continuous CO2 removal could be observed. We observed a median continuous CO2 removal of 49.2 mL/min (IQR: 26.9-72.3 mL/min) with some treatments achieving up to 160 mL/min. The CO2 removal significantly correlated with blood flow (Pearson 0.421; P < .001), PaCO2 (0.341, P < .001) and HCO 3 - levels (0.568, P < .001) at the start of the treatment. The continuous treatment led to a significant reduction in PaCO2 from baseline to the last ADVOS treatment. In conclusion, it was feasible to remove CO2 using the ADVOS system in our cohort of COVID-19 patients with acute respiratory distress syndrome and multiorgan failure. This efficient removal of CO2 was achieved at blood flows up to 300 mL/min using a conventional hemodialysis catheter and without a membrane lung or a gas phase.
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COVID-19/terapia , Dióxido de Carbono/sangre , Circulación Extracorporea/instrumentación , Pulmón/fisiopatología , Insuficiencia Multiorgánica/terapia , Diálisis Renal/instrumentación , Respiración Artificial , Anciano , COVID-19/sangre , COVID-19/diagnóstico , COVID-19/fisiopatología , Enfermedad Crítica , Circulación Extracorporea/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Insuficiencia Multiorgánica/sangre , Insuficiencia Multiorgánica/diagnóstico , Insuficiencia Multiorgánica/fisiopatología , Diálisis Renal/efectos adversos , Respiración Artificial/efectos adversos , Factores de Tiempo , Resultado del TratamientoRESUMEN
Extracorporeal circulatory devices such as hemodialysis and extracorporeal membrane oxygenation can be lifesaving; however, they are also prone to pathologic events including device failure, venous and arterial thrombosis, hemorrhage, and an accelerated risk for atherosclerotic disease due to interactions between blood components and device surfaces of varying biocompatibility. While extracorporeal devices may be used acutely for limited periods of time (eg, extracorporeal membrane oxygenation, continuous venovenous hemofiltration, therapeutic apheresis), some patients require chronic use of these technologies (eg, intermittent hemodialysis and left ventricular assist devices). Given the substantial thrombotic risks associated with extracorporeal devices, multiple antiplatelet and anticoagulation strategies-including unfractionated heparin, low-molecular-weight heparin, citrate, direct thrombin inhibitors, and direct oral anticoagulants, have been used to mitigate the thrombotic milieu within the patient and device. In the following manuscript, we outline the current data on anticoagulation strategies for commonly used extracorporeal circulatory devices, highlighting the potential benefits and complications involved with each.
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Anticoagulantes/administración & dosificación , Circulación Extracorporea/instrumentación , Adulto , Factores de Edad , Anticoagulantes/efectos adversos , Coagulación Sanguínea , Toma de Decisiones Clínicas , Manejo de la Enfermedad , Duración de la Terapia , Circulación Extracorporea/efectos adversos , Circulación Extracorporea/métodos , Hemorragia/etiología , Humanos , Trombosis/etiologíaRESUMEN
BACKGROUND: A wearable artificial lung could improve lung transplantation outcomes by easing implementation of physical rehabilitation during long-term pretransplant respiratory support. The Modular Extracorporeal Lung Assist System (ModELAS) is a compact pumping artificial lung currently under development. This study evaluated the long-term in vivo performance of the ModELAS during venovenous support in awake sheep. Feedback from early trials and computational fluid dynamic analysis guided device design optimization along the way. METHODS: The ModELAS was connected to healthy sheep via a dual-lumen cannula in the jugular vein. Sheep were housed in a fixed-tether pen while wearing the device in a holster during support. Targeted blood flow rate and support duration were 2-2.5 L/min and 28-30 days, respectively. Anticoagulation was maintained via systemic heparin. Device pumping and gas exchange performance and hematologic indicators of sheep physiology were measured throughout support. RESULTS: Computational fluid dynamic-guided design modifications successfully decreased pump thrombogenicity from initial designs. For the optimized design, 4 of 5 trials advancing past early perioperative and cannula-related complications lasted the full month of support. Blood flow rate and CO2 removal in these trials were 2.1 ± 0.3 L/min and 139 ± 15 mL/min, respectively, and were stable during support. One trial ended after 22 days of support due to intradevice thrombosis. Support was well tolerated by the sheep with no signs of hemolysis or device-related organ impairment. CONCLUSIONS: These results demonstrate the ability of the ModELAS to provide safe month-long support without consistent deterioration of pumping or gas exchange capabilities.
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Órganos Artificiales , Circulación Extracorporea/instrumentación , Trasplante de Pulmón , Pulmón/cirugía , Intercambio Gaseoso Pulmonar , Respiración , Animales , Diseño de Equipo , Circulación Extracorporea/efectos adversos , Pulmón/fisiopatología , Circulación Pulmonar , Oveja Doméstica , Factores de TiempoRESUMEN
Extracorporeal circulation (ECC) is an integral part of cardiac surgery. Yet, the contact with artificial surfaces, mechanical stress, shear, and suction forces within the ECC pose a pronounced risk for damaging the corpuscular components of the blood. These suction forces may be reduced by a repositioning of the roller pumps employed below the reservoir. Furthermore, the repeated compression of the involved silicone tubing is likely to cause degradation. We present our observations regarding changes in the ECC performance following this degradation process. In vitro experiments were performed in a standard as well as a simplified ECC setup and included measurements of pressure, effective flow, and tubing restoring force over a time frame of 12 hours with two different pump positions utilizing transit time flow measurement. Suction forces within the tubing could be significantly reduced by shifting the pump position below the reservoir. Regardless of the setup, the tubing showed significant loss of restoring force as well as effective flow over time. A shift of the pump position within the ECC setup can be recommended to prevent blood damaging negative pressures. Further research is necessary to evaluate the exact cause of the reduction of restoring force overtime as well as its risks for the patients. Finally, our results underline the importance of transit time flow measurements to collect reliable flow data.
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Procedimientos Quirúrgicos Cardíacos/instrumentación , Circulación Extracorporea/instrumentación , Estrés Mecánico , Hidrodinámica , Presión/efectos adversos , Resistencia al Corte , VacioRESUMEN
We describe the clinical course and treatment of a 53-year-old female, with small chest dimensions, referred to our institution for a primary cardiogenic shock. The patient underwent an on-pump left ventricular assist-device (VAD) implantation with the aid of immediate post-operative paracorporeal right-VAD assistance for an acute right ventricular failure. After two unsuccessful weaning attempts, she underwent extrapericardial HM 3 RVAD implantation.
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Insuficiencia Cardíaca/cirugía , Corazón Auxiliar , Choque Cardiogénico/cirugía , Tórax/patología , Tamaño Corporal/fisiología , Procedimientos Quirúrgicos Cardiovasculares/instrumentación , Procedimientos Quirúrgicos Cardiovasculares/métodos , Circulación Extracorporea/instrumentación , Circulación Extracorporea/métodos , Femenino , Insuficiencia Cardíaca/patología , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Implantación de Prótesis de Válvulas Cardíacas/instrumentación , Implantación de Prótesis de Válvulas Cardíacas/métodos , Corazón Auxiliar/efectos adversos , Humanos , Persona de Mediana Edad , Complicaciones Posoperatorias/terapia , Choque Cardiogénico/patología , Resultado del TratamientoRESUMEN
Extracorporeal circulation is vital in cardiovascular surgery, but thrombus formation at connector interface is a major threat. Optical coherence tomography (OCT) is presently used to monitor thrombogenesis at connectors, but it is expensive to install and complex to use. This study fabricated and evaluated a connector sensor for real-time permittivity-based thrombus monitoring at tube-connector interface. Computational simulations were initially done to pre-evaluate the applicability of connector sensor. The sensor was fabricated by incorporating two stainless steel electrodes on acrylic tube for measuring permittivity changes at the tube-connector interface. OCT images were also taken from the interface at intervals for comparisons. Results show that the sensor was able to detect thrombus formation at the interface in form of sudden rise in permittivity after time t = 9 min. The permittivity changes were confirmed by OCT images which showed thrombus formation after time t = 14 min implying that permittivity changes were due to regional aggregation of red blood cells. The connector sensor is therefore envisioned as an affordable alternative to OCT for real-time permittivity-based monitoring of thrombogenesis at tube-connector interface.
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Circulación Extracorporea/instrumentación , Trombosis/diagnóstico , Animales , Circulación Extracorporea/efectos adversos , Oxigenación por Membrana Extracorpórea , Trombosis/etiología , Tomografía de Coherencia ÓpticaRESUMEN
Roller pumping results in hemolysis and adverse effects on coagulation, but there are few reports on the influence of roller heads on platelets. Here, we evaluate the interaction between roller pumping and platelet function using a simulated extracorporeal circuit incorporating a vinyl chloride tube and roller head pump with 30 min recirculation. Platelet aggregation, platelet count, microparticle, P-selectin, Phosphatidylserine (PS) exposure and Ricinus Communis Agglutinin 1 (RCA-1) were measured before, 5, 10, 20, and 30 min after the recirculation using 100 ml of fresh human blood that had obtained from healthy volunteers (n = 9). Platelet aggregation and platelet count gradually decreased but microparticles significantly increased after the recirculation (P < 0.05). P-selectin, PS exposure and RCA-1 were measured using flow cytometry. There were no significant differences in the P-selectin and PS exposure expression during recirculation. RCA-1, a platelet apoptosis markers, significantly increased 30 min after recirculation (P < 0.05). We thus conclude that roller pumping induced platelet apoptosis and caused decreases in platelet count and aggregation after the recirculation.
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Plaquetas , Circulación Extracorporea/efectos adversos , Circulación Extracorporea/instrumentación , Agregación Plaquetaria , Adulto , Apoptosis , Coagulación Sanguínea , Hemólisis , Humanos , Masculino , Selectina-P/sangre , Recuento de Plaquetas , Adulto JovenRESUMEN
Cannulas with multi-staged side holes are the method of choice for femoral cannulation in extracorporeal therapies today. A variety of differently designed products is available on the market. While the preferred tool for the performance assessment of such cannulas are pressure-flow curves, little is known about the flow and velocity distribution. Within this work flow and velocity patterns of a femoral venous cannula with multi-staged side holes were investigated. A mock circulation loop for cannula performance evaluation was built and reproduced using a computer-aided design system. With computational fluid dynamics, volume flows and fluid velocities were determined quantitatively and visually with hole-based precision. In order to ensure the correctness of the flow simulation, the results were subsequently validated by determining the same parameters with four-dimensional flow-sensitive magnetic resonance imaging. Measurement data and numerical solution differed 7% on average throughout the data set for the examined parameters. The highest inflow and velocity were detected at the most proximal holes, where half of the total volume flow enters the cannula. At every hole stage a Y-shaped inflow profile was detected, forming a centered stream in the middle of the cannula. Simultaneously, flow separation creates zones with significant lower flow velocities. Numerical simulation, validated with four-dimensional flow-sensitive magnetic resonance imaging, is a valuable tool to examine flow and velocity distributions of femoral venous cannulas with hole-based accuracy. Flow and velocity distribution in such cannulas are not ideal. Based on this work future cannulas can be effectively optimized.
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Diseño Asistido por Computadora , Diseño de Equipo/métodos , Circulación Extracorporea/instrumentación , Modelos Cardiovasculares , Velocidad del Flujo Sanguíneo/fisiología , Cateterismo/instrumentación , Circulación Extracorporea/métodos , Arteria Femoral/diagnóstico por imagen , Arteria Femoral/fisiología , Arteria Femoral/cirugía , Humanos , Imagen por Resonancia Magnética/métodosRESUMEN
Extracorporeal CO2 removal (ECCO2R) can permit lung protective or noninvasive ventilation strategies in patients with chronic obstructive pulmonary disease (COPD) and acute respiratory distress syndrome (ARDS). With evidence supporting ECCO2R growing, investigating factors which affect CO2 removal is necessary. Multiple factors are known to affect the CO2 removal rate (vCO2) which can complicate the interpretation of changes in vCO2; however, the effect of hematocrit on the vCO2 of artificial lungs has not been investigated. This in vitro study evaluates the relationship between hematocrit level and vCO2 within an ECCO2R device. In vitro gas transfer was measured in bovine blood in accordance with the ISO 7199 standard. Plasma and saline were used to hemodilute the blood to hematocrits between 33% and 8%. The vCO2 significantly decreased as the blood was hemodiluted with saline and plasma by 42% and 32%, respectively, between a hematocrit of 33% and 8%. The hemodilution method did not significantly affect the vCO2. In conclusion, the hematocrit level significantly affects vCO2 and should be taken into account when interpreting changes in the vCO2 of an ECCO2R device.
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Órganos Artificiales , Dióxido de Carbono/sangre , Circulación Extracorporea/métodos , Hematócrito , Pulmón , Animales , Bovinos , Circulación Extracorporea/instrumentación , Ventilación no Invasiva/métodos , Enfermedad Pulmonar Obstructiva Crónica , Síndrome de Dificultad RespiratoriaRESUMEN
A minimized perfusion circuit (MPC) may reduce transfusion requirement and inflammatory response. Its use, however, has not been standardized for complicated cardiovascular surgery. We assessed outcomes of surgery for acute type A aortic dissection (ATAAD) performed with a MPC under circulatory arrest. The study involved 706 patients treated surgically for ATAAD (by hemiarch repair [n = 571] or total arch repair [n = 135]). Total arch repair was performed using selective antegrade cerebral perfusion. Our MPC, a semi-closed bypass system, incorporating a completely closed circuit and a level-sensing reservoir in the venous circuit, was used. Clinical variables, transfusion volume, and outcomes were investigated in patients who underwent hemiarch repair or total arch repair. The overall incidences of shock, organ ischemia, and coagulopathy (prothrombin time-international normalized ratio >1.5) were 26%, 35%, and 8%, respectively. Mean extracorporeal circulation (ECC) time was 149 minutes for the hemiarch repair group and 241 minutes for the total arch repair group, respectively. No patient required conversion to conventional ECC, and there were no complications related to the use of the MPC. The need for transfusion (98% vs. 91%, P = .017) and median transfusion volume (1970 vs. 1680 mL, P = .002) was increased in the total arch repair group. Neither in-hospital mortality (total arch; 12% vs. hemiarch; 7%, P = .11) nor 10-year survival (74.4% vs. 68.4%, P = .79) differed significantly. Outcomes of surgery for ATAAD performed with the MPC were acceptable. The possibility of transfusion and transfusion volume remains high during such surgery, despite the use of the MPC.
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Disección Aórtica/cirugía , Procedimientos Quirúrgicos Vasculares/instrumentación , Anciano , Diseño de Equipo , Circulación Extracorporea/instrumentación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Perfusión/instrumentación , Resultado del TratamientoRESUMEN
Severe pulmonary impairment can occur after traumatic brain injury or stroke. The resulting brain-lung interactions represent key points for the treatment and the subsequent outcome of the patient. Established treatment approaches, such as permissive hypercapnia and prone positioning, present the intensive care physician with divergent treatment goals in these patients with partially increased intracranial pressure. This case report series shows the instrument-based and noninstrument-based options for the treatment of acute respiratory distress syndrome (ARDS) in the simultaneous presence of intracranial pathologies. This includes equipment based therapies using extracorporeal CO2 elimination, special positioning maneuvers in specially designed hospital beds and positional maneuvers, such as prone positioning. With enhanced neuromonitoring it is possible to optimally adapt treatment measures focused on the lungs early and before secondary damage to the brain.
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Lesiones Encefálicas/complicaciones , Lesiones Encefálicas/terapia , Circulación Extracorporea/métodos , Síndrome de Dificultad Respiratoria/complicaciones , Síndrome de Dificultad Respiratoria/terapia , Adulto , Edema Encefálico , Cuidados Críticos , Descarboxilación/fisiología , Circulación Extracorporea/instrumentación , Oxigenación por Membrana Extracorpórea , Escala de Coma de Glasgow , Humanos , Pulmón , Masculino , Persona de Mediana Edad , Posicionamiento del Paciente , Posición Prona/fisiología , Síndrome de Dificultad Respiratoria/fisiopatologíaAsunto(s)
Circulación Extracorporea/instrumentación , Cardiopatías/terapia , Puente Cardiopulmonar/instrumentación , Puente Cardiopulmonar/métodos , Niño , Congresos como Asunto , Circulación Extracorporea/métodos , Cardiopatías/cirugía , Corazón Auxiliar , Humanos , Ohio , Pediatría/instrumentación , Pediatría/métodos , Perfusión/instrumentación , Perfusión/métodosRESUMEN
Extracorporeal cardiopulmonary resuscitation (ECPR) can be associated with increased survival and neurologic benefits in selected patients with out-of-hospital cardiac arrest (OHCA). However, there remains insufficient evidence to recommend the routine use of ECPR for patients with OHCA. A novel integrated trauma workflow concept that utilizes a sliding computed tomography (CT) scanner and interventional radiology (IR) system, named a hybrid emergency room system (HERS), allowing emergency therapeutic interventions and CT examination without relocating trauma patients, has recently evolved in Japan. HERS can drastically shorten the ECPR implementation time and more quickly facilitate definitive interventions than the conventional advanced cardiovascular life support workflow. Herein, we discuss our novel workflow concept using HERS on ECPR for patients with OHCA.
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Reanimación Cardiopulmonar , Prestación Integrada de Atención de Salud/organización & administración , Servicio de Urgencia en Hospital/organización & administración , Circulación Extracorporea , Modelos Organizacionales , Paro Cardíaco Extrahospitalario/terapia , Radiografía Intervencional , Tomografía Computarizada por Rayos X , Imagen de Cuerpo Entero , Reanimación Cardiopulmonar/instrumentación , Vías Clínicas/organización & administración , Circulación Extracorporea/instrumentación , Humanos , Paro Cardíaco Extrahospitalario/diagnóstico por imagen , Paro Cardíaco Extrahospitalario/fisiopatología , Grupo de Atención al Paciente/organización & administración , Desarrollo de Programa , Radiografía Intervencional/instrumentación , Factores de Tiempo , Tiempo de Tratamiento/organización & administración , Tomografía Computarizada por Rayos X/instrumentación , Imagen de Cuerpo Entero/instrumentación , Flujo de TrabajoRESUMEN
An abnormal elevation in pressure is a serious complication involving the extracorporeal circulation circuit. Clot formation might be associated with this complication, but the precise mechanism of an abnormal elevation in pressure has not been identified. We investigated sufficient conditions for in-circuit elevation in pressure using an ex vivo re-circulation circuit with porcine blood. Specifically, we investigated the effect of blood conditions, the type of anticoagulation, and pro-inflammatory stimulation on in-circuit pressure. We also examined the cause of an abnormal elevation of in-circuit pressure by specifically degrading DNA, RNA, or protein components of an obstructed filter and by using immunofluorescent techniques. Neither a change in temperature nor change in pH in the blood increased in-circuit pressure. In contrast, long-term storage of blood, pro-inflammatory stimulation by phorbol myristate acetate, and heparin administration significantly increased in-circuit pressure. Abnormal in-circuit elevation in pressure was associated with deposition of extracellular DNA on the outlet surface of the filter. Administration of DNase resulted in a rapid decline of in-circuit pressure. In an ex vivo re-circulation circuit system, extracellular DNA deposition on the filter is responsible for an abnormal in-circuit elevation in pressure. Senescent leukocytes, stimulated leukocytes, and heparin exposure are associated with extracellular DNA deposition.
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ADN/metabolismo , Circulación Extracorporea/instrumentación , Filtración/instrumentación , Leucocitos/metabolismo , Presión , Animales , Hemodinámica , PorcinosRESUMEN
We retrospectively reviewed the medical records of 11 patients supported with a veno-venous low-flow extracorporeal carbon dioxide (CO2) removal (ECCO2R) device featuring a large gas exchange surface membrane lung (ML) (i.e., 1.8 m). Seven patients suffered from exacerbation of a chronic pulmonary disease, while four subjects were affected by acute respiratory distress syndrome (ARDS). Twenty-four hours of ECCO2R treatment reduced arterial PCO2 from 63 ± 12 to 54 ± 11 mm Hg (p < 0.01), increased arterial pH from 7.29 ± 0.07 to 7.39 ± 0.06 (p < 0.01), and decreased respiratory rate from 32 ± 10 to 21 ± 8 bpm (p < 0.05). Extracorporeal blood flow and CO2 removal were 333 ± 37 and 94 ± 18 ml/min, respectively. The median duration of ECCO2R treatment was 7 days (6.5-9.5). All four ARDS patients were invasively ventilated at the time of treatment start, no one was extubated and they all died. Among the seven patients with exacerbation of chronic pulmonary diseases, four were managed with noninvasive ventilation at ECCO2R institution, while three were extubated after starting the extracorporeal treatment. No one of these seven patients was intubated or re-intubated after ECCO2R institution and five (71%) survived to hospital discharge. A low-flow ECCO2R device with a large surface ML removes a relevant amount of CO2 resulting in a decreased arterial PCO2, an increased arterial pH, and in a reduced ventilatory load.
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Dióxido de Carbono/sangre , Circulación Extracorporea/instrumentación , Circulación Extracorporea/métodos , Síndrome de Dificultad Respiratoria/terapia , Insuficiencia Respiratoria/terapia , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
The modalities of vascular access for the extracorporeal artificial placenta (AP) have undergone many iterations over the past decade. We hypothesized that single lumen cannulation (SLC) of the jugular vein using tidal flow extracorporeal life (ECLS) support is a feasible alternative to venovenous (VV) umbilical-jugular cannulation and double lumen cannulation (DLC) and can maintain fetal circulation, stable hemodynamics, and adequate gas exchange for 24 hours. After in vitro evaluation of the tidal flow system, six preterm lambs at estimated gestational age 118-124 days (term 145 days) were delivered and underwent VV-ECLS. Three were supported using DLC and three with SLC utilizing tidal flow AP support. Hemodynamics, circuit flow, and gas exchange were monitored. Target fetal parameters were as follows: mean arterial pressure 40-60 mmHg, heart rate 140-240 beats per minute (bpm), SatO2% 60-80%, PaO2 25-50 mmHg, PaCO2 30-55 mmHg, oxygen delivery >5 ml O2/dl/kg/min, and circuit flow 100 ± 25 ml/kg/min. All animals survived 24 hours and maintained fetal circulation with stable hemodynamics and adequate gas exchange. Parameters of the tidal flow group were comparable with those of DLC. Single lumen jugular cannulation using tidal flow is a promising vascular access strategy for AP support. Successful miniaturization holds great potential for clinical translation to support extremely premature infants.
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Órganos Artificiales , Circulación Extracorporea/métodos , Placenta , Animales , Animales Recién Nacidos , Circulación Extracorporea/instrumentación , Femenino , Feto , Hemodinámica/fisiología , Perfusión/instrumentación , Perfusión/métodos , Embarazo , Ovinos , Oveja DomésticaRESUMEN
PURPOSE: Acute liver failure (ALF) and acute on chronic liver failure (ACLF) are associated with significant mortality and morbidity. Extracorporeal liver support (ECLS) devices have been used as a bridge to liver transplant; however, the efficacy and safety of ECLS are unclear. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to examine the efficacy and safety of ECLS in liver failure. METHODS: We searched MEDLINE, EMBASE and Cochrane Central Register of Controlled Trials from inception through March 13, 2019. RCTs comparing ECLS to usual care in ALF or ACLF were included. We used the Grading of Recommendations Assessment, Development and Evaluation approach to assess the certainty of the evidence. RESULTS: We identified 25 RCTs (1796 patients). ECLS use was associated with reduction in mortality (RR 0.84; 95% CI 0.74, 0.96, moderate certainty) and improvement in hepatic encephalopathy (HE) (RR 0.71; 95% CI 0.60, 0.84, low certainty) in patients with ALF or ACLF. The effect of ECLS on hypotension (RR 1.46; 95% CI 0.98, 2.2, low certainty), bleeding (RR 1.21; 95% CI 0.88, 1.66, moderate certainty), thrombocytopenia (RR 1.62; 95% CI 1.0, 2.64, very low certainty) and line infection (RR 1.92; 95% CI 0.11, 33.44, low certainty) was uncertain. CONCLUSIONS: ECLS may reduce mortality and improve HE in patients with ALF and ACLF. The effect on other outcomes is uncertain. However, the evidence is limited by risk of bias and imprecision, and larger trials are needed to better determine the effect of ECLS on patient-important outcomes.
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Circulación Extracorporea/métodos , Fallo Hepático/terapia , Circulación Extracorporea/instrumentación , Circulación Extracorporea/tendencias , Humanos , Fallo Hepático/fisiopatología , Ensayos Clínicos Controlados Aleatorios como Asunto/normas , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricosRESUMEN
BACKGROUND: Compromised microvasculature resulting from disrupted bronchial arterial circulation appears to trigger chronic lung allograft dysfunction. Maintaining the microvasculature throughout the transplant process could improve the long-term health of transplanted lungs. We recently developed a bronchial-arterial-circulation-sparing (BACS) lung preservation approach and tested whether this approach would decrease microvascular damage and improve allograft function. METHODS: The lungs of Lewis rats were procured using either the BACS approach, where the bronchial and pulmonary arteries were synchronously perfused; a conventional approach, where only the pulmonary artery was perfused; or a conventional approach with a prostaglandin flush. After 4 hours of cold ischemia, physiologic function and vascular tone of the grafts were evaluated during ex vivo lung perfusion (EVLP), and microvasculature damage was assessed using 2-photon microscopy analysis. Lung function was compared after transplant among the groups. RESULTS: After 4 hours of cold ischemia, the BACS group exhibited significantly higher adenosine triphosphate levels and lower expression of phosphorylated myosin light chain, which is essential for vascular smooth muscle contraction. On EVLP, the BACS and prostaglandin groups showed lower pulmonary vascular resistance and less arterial stiffness. BACS attenuated microvasculature damage in the lung grafts when compared with conventional preservation. After transplantation, the lungs preserved with the BACS approach exhibited significantly better graft function and lower expression of phosphorylated myosin light chain. CONCLUSIONS: Our data suggest that BACS lung preservation protects the dual circulation inherent to the lungs, facilitating robust microvasculature in lung grafts after transplantation, leading to better posttransplant outcomes.