Venous-venous Extracorporeal Membrane Oxygenation Research Articles

Extra corporeal membrane oxygenation in the critical trauma patient

The purpose of this review is to describe recent evidence regarding the use of extracorporeal membrane oxygenation (ECMO) as salvage therapy for severe cardiac or respiratory failure in patients with trauma. The characteristics of this cohort of patients, including the risk of bleeding and the need for systemic anticoagulation, are generally considered as relative contraindications to ECMO treatment. However, recent evidence suggests that the use of ECMO should be taken in consideration even in this group of patients. The recent findings suggest that venous-venous ECMO can be feasible in the treatment of refractory respiratory failure and severe acute respiratory distress syndrome trauma-related. The improvement of ECMO techniques including the introduction of centrifugal pumps and heparin-coated circuits are progressively reducing the amount of heparin required; moreover, the application of heparin-free ECMO showed good outcomes and minimal complications. Venous-arterial ECMO has emerged as a salvage intervention in patients with cardiogenic shock and after cardiac arrest. Venous-arterial ECMO provides circulatory support allowing time for other treatments to promote recovery in presence of acute cardiopulmonary failure. Only poor-quality evidence is available, for venous-arterial ECMO in trauma patients. ECMO can be considered as a safe rescue therapy even in trauma patients, including neurological injury, chest trauma as well as burns. However, evidence is still poor; further studies are warranted focusing on trauma patients undergoing ECMO, to better clarify the effect on survival, the type and dose of anticoagulation to use, as well as the utility of dedicated multidisciplinary trauma-ECMO units.

An audit of mortality by using ECMO specific scores and APACHE II scoring system in patients receiving extracorporeal membrane oxygenation in a tertiary intensive care unit in Hong Kong

Outcomes of patients receiving extracorporeal membrane oxygenation (ECMO) therapies risk-adjusted by ECMO specific scores have rarely been reported. Our primary aim was to determine the risk adjusted outcome of these patients by the use of Respiratory Extracorporeal Membrane Oxygenation Survival Prediction (RESP), Survival After Veno-Arterial-ECMO (SAVE) and APACHE II scores. The differences in predicted mortality between these scoring systems were analyzed. This is a single-center retrospective study reviewing 62 patients who received venous-venous ECMO (VV-ECMO) and venous-arterial ECMO (VA-ECMO) between 2009 and 2017 in a tertiary ICU. Demographic, clinical, laboratory, imaging data were analyzed. Primary outcome measures were the crude mortality and standardized mortality ratio (SMR), expressed as observed mortality divided by expected mortality predicted from RESP, SAVE and APACHE II scores, respectively. We also examined the difference in predicted mortality derived from RESP, SAVE, and APACHE II by using Bland Altman plots. Twenty and Forty-two patients received VV-ECMO (20 runs) and VA-ECMO (43 runs) respectively. For VV-ECMO, the mean RESP was 0.6 [standard deviation (SD) 4.86] with RESP-SMR of 1.16 [95% confidence interval (95% CI) =0.44-1.88]. For VA-ECMO, the mean SAVE score was -7.8 (SD 5.6), with SAVE-SMR of 0.69 (95% CI =0.39-0.98). In the Bland Altman plot for VA-ECMO, mean difference in predicted mortality between SAVE and APACHE II was 17.6% (95% CI: 7.6% to 27.6%, P<0.0001), with 95% limit of agreement of -30.2% to 65.5% and beta coefficient of -1.04. APACHE II predicted mortality for VA-ECMO was lower than that for SAVE until it crossed SAVE prediction at about 80% mortality. After this point, it becomes progressively higher than that for SAVE. The mortality outcome of our patients on VV-ECMO and VA-ECMO compares favorably with predicted mortality based on RESP and SAVE, respectively. In our cohort of patients receiving VA-ECMO, APACHE II tends to underestimate mortality in lower risk patients, and overestimate the mortality in patients at high risk of death.

Oxygen delivery, carbon dioxide removal, energy transfer to lungs and pulmonary hypertension behavior during venous-venous extracorporeal membrane oxygenation support: a mathematical modeling approach.

ObjectiveTo describe (1) the energy transfer from the ventilator to the lungs, (2) the match between venous-venous extracorporeal membrane oxygenation (ECMO) oxygen transfer and patient oxygen consumption (VO2), (3) carbon dioxide removal with ECMO, and (4) the potential effect of systemic venous oxygenation on pulmonary artery pressure.MethodsMathematical modeling approach with hypothetical scenarios using computer simulation.ResultsThe transition from protective ventilation to ultraprotective ventilation in a patient with severe acute respiratory distress syndrome and a static respiratory compliance of 20mL/cm H2O reduced the energy transfer from the ventilator to the lungs from 35.3 to 2.6 joules/minute. A hypothetical patient, hyperdynamic and slightly anemic with VO2 = 200mL/minute, can reach an arterial oxygen saturation of 80%, while maintaining the match between the oxygen transfer by ECMO and the VO2 of the patient. Carbon dioxide is easily removed, and normal PaCO2 is easily reached. Venous blood oxygenation through the ECMO circuit may drive the PO2 stimulus of pulmonary hypoxic vasoconstriction to normal values.ConclusionUltraprotective ventilation largely reduces the energy transfer from the ventilator to the lungs. Severe hypoxemia on venous-venous-ECMO support may occur despite the matching between the oxygen transfer by ECMO and the VO2 of the patient. The normal range of PaCO2 is easy to reach. Venous-venous-ECMO support potentially relieves hypoxic pulmonary vasoconstriction.

Extracorporeal membrane oxygenation after lung transplantation: risk factors and outcomes analysis.

Lung transplantation is the treatment of choice for end-stage pulmonary disease in selected patients. However, severe primary graft dysfunction is a significant complication of transplant and requires the implantation of an extracorporeal support. The aim of the study is to evaluate the impact of extracorporeal membrane oxygenation (ECMO) after transplant in our center. From January 2008 till June 2018, 195 consecutive unselected patients receiving a lung transplant were considered. Mean age was 49±15 years. Main indications for transplant were idiopathic pulmonary fibrosis in 72 patients, chronic obstructive pulmonary disease in 60 patients, and cystic fibrosis in 40 patients. Prior to transplant, 18 patients were on mechanical ventilation and 14 were on ECMO. Twenty-five patients required venous-venous ECMO after transplant. Vascular disease as cause of transplant [relative risk (RR) 7.8, 95% CI: 1.5-41, P=0.02], donor age (RR 1.6, 95% CI: 1.03-2.3, P=0.03) and need for cardiopulmonary by-pass during transplant (RR 3.1, 95% CI: 1.02-9, P=0.04) were associated with ECMO implantation. Patients requiring post-transplant ECMO received more transfusions (P<0.01), had a longer mechanical ventilation (P<0.01) and ICU stay (P<0.01) and had a higher hospital mortality (P<0.01). Post-transplant ECMO significantly influenced one- and five-year survival [hazard ratio (HR) 5.5, 95% CI: 3-10, P<0.001 and HR 3.5, 95% CI: 2-6, P<0.001, respectively]. However, conditional survival after t months is similar for patients with or without post-transplant ECMO. In our experience, although ECMO is a reliable and effective strategy to support pulmonary function, severe graft dysfunction after lung transplantation still has a significant impact on early and late results.

RF01 ANGIO-VAC ASPIRATION SYSTEM: THE LARGEST ITALIAN SINGLE CENTER EXPERIENCE

Background and Aim: AngioVac system is a vacuum-assisted venous drainage device recently introduced into clinical practice for the removal of fresh and/or soft emboli/thrombi from vessels and right atrium. The aim of this study was presenting our center experience. Methods: From July 2016 to July 2017, 6 patients (mean age 58 ± 15 years) were treated with AngioVac system for right atrial masses (=4, 66.7%, 2 of these were electrode lead vegetations) and thrombosis of inferior vena cava (=2, 33.3%). We used both femoral and jugular vein percutaneous accesses and echo- or fluoroscopy guiding. Results: Therapeutic success (defined as a complete aspiration of the mass or return to an anterograde caval flow) was achieved in 5 cases (83.3%). One percutaneous approach was converted in open-chest because of pericardial tamponade and the mass suction was performed directly through the right atrium. Median intensive care unit stay was 1 day and all patients were discharged in good clinical conditions. At 1-year follow-up, all patients were alive. Conclusions: In our experience, AngioVac is a safe and reliable device that allows good results and patient's fast recovery. Because the procedure requires patient monitoring and the use of venous-venous extracorporeal membrane oxygenation, we suggest performing it in cardiac or hybrid operating room.

Successful long-term extracorporeal membrane oxygenation for invasive pulmonary aspergillosis: a case report

BackgroundExtracorporeal membrane oxygenation is an established life-saving procedure for severe acute respiratory failure due to various causes. In general, the duration of extracorporeal membrane oxygenation ranges from 1 to 2 weeks, with withdrawal recommended if no improvement is noted. We report a successful case of long-term extracorporeal membrane oxygenation management for respiratory failure due to invasive pulmonary Aspergillus infection.Case presentationA 64-year-old Asian man with no previous underlying medical conditions was transferred to our hospital for fever and dyspnea. On admission, he presented with bilateral diffuse infiltration shadow on X-ray and chest computed tomography readings, and severe hypoxemia with a partial pressure of oxygen in arterial blood/fraction of inspired oxygen ratio of 55. He was intubated and underwent mechanical ventilation. A bronchial-alveolar lavage was performed prior to administration of antibiotics, and as the bacterial culture was positive for Aspergillus fumigatus, antifungal treatment was then initiated. His respiratory status deteriorated on the 11th admission day, with no improvement on any mechanical ventilator settings. Venous-venous extracorporeal membrane oxygenation was introduced. Extracorporeal membrane oxygenation was used for an extended period of time, with respiratory improvement delayed until the 39th admission day. Extracorporeal membrane oxygenation discontinuation was possible on the 44th day, and he was removed from the ventilator on the 64th day.ConclusionsLong-term extracorporeal membrane oxygenation might be considered if the primary causes of respiratory failure necessitating extracorporeal membrane oxygenation can be expected to be resolved, such as in the case of effective antimicrobial therapy for a definite pathogen. Our case indicates that extracorporeal membrane oxygenation can be used during treatment of respiratory failure due to invasive aspergillosis for the recommended treatment duration of 4 to 8 weeks.

Invited Commentary

Dr Roncon-Albuquerque, Jr and colleagues [1Roncon-Albuquerque Jr., R. Ferreira-Coimbra J. Vilares-Morgado R. Figueiredo P. Paiva J.A. PaO2/FiO2 deterioration during stable extracorporeal membrane oxygenation associates with protracted recovery and increased mortality in severe acute respiratory distress syndrome.Ann Thorac Surg. 2016; 102: 1878-1885Abstract Full Text Full Text PDF PubMed Scopus (5) Google Scholar] evaluated the effect of changes in Pao2/Fio2 (P/F) ratios between day 1 and day 7 after the institution of venous-venous (VV) extracorporeal membrane oxygenation (ECMO) for severe acute respiratory distress syndrome. They demonstrated a marked difference in patient outcomes for patients presenting an improving P/F ratio in1 week versus a decreasing P/F, eg, mortality was significantly decreased with an improving P/F ratio (22% versus 48%). Many factors can affect systemic blood oxygenation during VV ECMO. Among the most important are ECMO flow versus cardiac output and the residual lung function contribution. Other factors include recirculation (fraction of oxygenated circuit blood drained back to the circuit by the drainage cannula), body temperature, and oxygen extraction rate. The main message of this study is that the P/F ratio during the first week of an ECMO run can have significant prognostic value. However, it is likely that this is simply a representation of patients with less severe lung injury, leading to a more rapid recovery of native lung function. However, other important patient factors, such as absence of sepsis and therefore a less hyperdynamic patient (increased ratio between the blood oxygenated by the artificial lung and the patients' venous blood), may play a role in both the P/F ratio and final patient outcomes. Although the relatively low number of patients is a weakness of this study, the single-institution, well-standardized ventilation protocols before and after ECMO and consistent ECMO techniques (dual-cannula VV) and management add significant value to the findings. Once this is confirmed in a larger number of patients, the variation of P/F ratio in the first week after the institution of VV ECMO could be used as a simple prognostic marker that could aid not only in informing the patient’s family of his or her ultimate chance of recovery but also in the prediction of hospital resource use. Finally, it can also be used to stratify more equal groups for novel therapeutic trials in ECMO for acute respiratory distress syndrome. PaO2/FiO2 Deterioration During Stable Extracorporeal Membrane Oxygenation Associates With Protracted Recovery and Increased Mortality in Severe Acute Respiratory Distress SyndromeThe Annals of Thoracic SurgeryVol. 102Issue 6PreviewDuring extracorporeal membrane oxygenation (ECMO), arterial oxygen partial pressure to fractional inspired oxygen (PaO2/FiO2; PF ratio reflects native and artificial lung blood oxygenation). In this study we analyzed PF ratio during ECMO support and its association with clinical outcome. Full-Text PDF

Daily nursing care on patients undergoing venous-venous extracorporeal membrane oxygenation: a challenging procedure!

Daily nursing in critical care patients may alter vital parameters, especially in the most critically ill patients. The aim of our study was to evaluate feasibility and safety of daily nursing on patients undergoing venous-venous extracorporeal membrane oxygenation (vv-ECMO) for severe respiratory failure. Daily nursing was performed following defined phases (sponge bath, elevation with scooping stretcher, change position of endotracheal tube, dressing replacement). We recorded physiological and ECMO parameters before and during daily nursing in 5 patients for several days (total: 25 daily nursing) and adverse events: desaturation, hypertension, reduction of mixed venous oxygen saturation, arterial oxygen saturation or ECMO blood flow and elevation in minute ventilation. Sedative drug dosage and additional bolus were recorded. Daily nursing was performed in 92% of cases (23/25), with a minimum of two adverse events per daily nursing. Hypertension and tachycardia were mostly recorded at the beginning, while desaturation, reduction in mixed venous oxygen saturation and blood flow were recorded during elevation with scooping stretcher. Increase in minute ventilation was frequent in spontaneous breathing patients. Additional bolus of sedation was required before and/or during nursing. Daily nursing significantly alters physiologic parameters; thus, it should be performed only when physicians are readily available to treat adverse events.

Cerebral Autoregulation in Patients Treated With V-Vecmo For Severe Ards

In patients with severe ARDS refractory to conventional mechanical ventilation, venous-venous extracorporeal membrane oxygenation (v-vECMO) is a rescue therapy able to restore normal values of PaO2 and PaCO2, maintaining the lung at rest. Hypoxemia and hypercapnia occurring in patients with severe ARDS may negatively affect cerebral autoregulation.

Effect of flow rate and temperature on transmembrane blood pressure drop in an extracorporeal artificial lung

Transmembrane pressure drop reflects the resistance of an artificial lung system to blood transit. Decreased resistance (low transmembrane pressure drop) enhances blood flow through the oxygenator, thereby, enhancing gas exchange efficiency. This study is part of a previous one where we observed the behaviour and the modulation of blood pressure drop during the passage of blood through artificial lung membranes. Before and after the induction of multi-organ dysfunction, the animals were instrumented and analysed for venous-venous extracorporeal membrane oxygenation, using a pre-defined sequence of blood flows. Blood flow and revolutions per minute (RPM) of the centrifugal pump varied in a linear fashion. At a blood flow of 5.5 L/min, pre- and post-pump blood pressures reached -120 and 450 mmHg, respectively. Transmembrane pressures showed a significant spread, particularly at blood flows above 2 L/min; over the entire range of blood flow rates, there was a positive association of pressure drop with blood flow (0.005 mmHg/mL/minute of blood flow) and a negative association of pressure drop with temperature (-4.828 mmHg/(°Celsius). These associations were similar when blood flows of below and above 2000 mL/minute were examined. During its passage through the extracorporeal system, blood is exposed to pressure variations from -120 to 450 mmHg. At high blood flows (above 2 L/min), the drop in transmembrane pressure becomes unpredictable and highly variable. Over the entire range of blood flows investigated (0-5500 mL/min), the drop in transmembrane pressure was positively associated with blood flow and negatively associated with body temperature.

Extracorporeal membrane oxygenation in adult patients with severe acute respiratory failure

A group of patients with severe acute respiratory distress syndrome (ARDS) is resistant to advanced respiratory therapy. In these patients, extracorporeal membrane oxygenation (ECMO) can be used as a rescue therapy. This study presents 14 years of experience from a Scandinavian ECMO centre. The aim of the study is to present outcome results and to investigate whether or not simplified acute physiology score II (SAPS-II), sequential organ failure assessment (SOFA) and/or Murray scores can be used to predict patients' outcome. In a prospective observational study, we collected data from ECMO patients from January 1997 to March 2011. The treatment was based mainly on venous-venous ECMO and centrifugal pumps. Patients were retrieved from Denmark plus a number from Sweden and Norway. The inclusion criteria were the classical criteria until November 2009 (n = 100), after which the new Extracorporeal Life Support Organisation criteria (n = 24) were used. One hundred and twenty-four patients were enrolled with median age 45 (range 16-67) years. The median Murray score was 3.7 (2.5-4.0). One hundred and six (85%) of the patients were retrieved from referring hospitals on ECMO. The median duration of the ECMO runs was 215 (1-578) h. Ninety-seven (78%) of the patients could be weaned from ECMO. A total of 88 (71%) were discharged alive to the referring hospitals. High SAPS-II, SOFA and Murray scores were associated with a high mortality. Patients with severe ARDS have a favourable outcome when treated with ECMO and when an ECMO retrieval team establishes the ECMO treatment at the referring hospital. SAPS-II, SOFA and Murray scores predicted the outcome.

The experience of extracorporeal membrane oxygenation for severe acute respiratory failure in adults

To summarize the experience of extracorporeal membrane oxygenation (ECMO) for patients with severe acute respiratory failure in adults and to investigate the factors associated with death. The clinical data of patients with severe acute respiratory failure supported with ECMO in respiratory intensive care unit of Beijing Chaoyang Hospital from November 2009 to December 2011 were prospectively collected and analyzed. The data included general condition before EMCO, blood gas analysis, hemodynamics, ventilator settings of mechanical ventilation and complications during ECMO. The primary outcome was death or severe disability within 3 months. Statistical software of SPSS (version 16.0) was used for data analysis. Twenty-five patients with severe respiratory failure received ECMO treatment, of which 16 patients were analyzed. The mean age was (45 ± 14) years old (range, 22 - 64 years old). Thirteen patients were male. Before ECMO, all of the patients were treated with invasive positive pressure ventilation for (72 ± 64) hours. Eight patients had been treated with noninvasive ventilation for a median of 55(10-114) hours. Patients had severe respiratory failure despite advanced mechanical ventilator support. The mean PaO2/fraction of inspired oxygenation (FiO2) ratio was (54 ± 18) mm Hg (1 mm Hg = 0.133 kPa), positive end-expiratory pressure (PEEP) was (11 ± 6) cm H2O(1 cm H2O = 0.098 kPa), Murray lung injury score was 3.6 ± 0.5, serum lactate was (2.5 ± 2.0) mmol/L, serum white blood cell count was (16 ± 6)×10(9)/L, and APACHEII score was 17 ± 8. All of the patients were treated with venous-venous ECMO (VV-ECMO). The change of mechanical ventilation settings were (pre-ECMO vs 2 hours post-ECMO): FiO2 1.0 vs 0.55 ± 0.21, PEEP (11 ± 6) vs (9 ± 6) cm H2O, V(T) (6.8 ± 2.2) vs (4.4 ± 2.0) ml/kg PBW, peak airway pressure (27 ± 8) vs (24 ± 7) cm H2O, respiratory rate (37 ± 10) vs (23 ± 10) breaths/min. Arterial blood gas, including pH, PaO2 and PaCO2 were significantly improved after ECMO running 24 and 48 hours (P < 0.05). The mean VV-ECMO support interval was (9.7 ± 9.6) days (range, 2 - 41 days). Ten patients were successfully weaned from ECMO, of whom 2 died in ICU. Three patients died during ECMO, while another 3 patients died after withdrawal of further treatment. Eight patients survived to 3 months without severe disability. In a multi-variate Cox regression model, pre-ECMO factors including lower PaO2/FiO2 and increasing white blood cell count were associated with increased risks of death (RR was 0.733, 1.701 respectively, both P values < 0.05). VV-ECMO is a potentially effective approach for severe acute respiratory failure. PaO2/FiO2 and white blood cell count pre-ECMO may be the risk factors for poor outcome.

First-year experience of a Brazilian tertiary medical center in supporting severely ill patients using extracorporeal membrane oxygenation

OBJECTIVES:The aim of this manuscript is to describe the first year of our experience using extracorporeal membrane oxygenation support.METHODS:Ten patients with severe refractory hypoxemia, two with associated severe cardiovascular failure, were supported using venous-venous extracorporeal membrane oxygenation (eight patients) or veno-arterial extracorporeal membrane oxygenation (two patients).RESULTS:The median age of the patients was 31 yr (range 14–71 yr). Their median simplified acute physiological score three (SAPS3) was 94 (range 84–118), and they had a median expected mortality of 95% (range 87–99%). Community-acquired pneumonia was the most common diagnosis (50%), followed by P. jiroveci pneumonia in two patients with AIDS (20%). Six patients were transferred from other ICUs during extracorporeal membrane oxygenation support, three of whom were transferred between ICUs within the hospital (30%), two by ambulance (20%) and one by helicopter (10%). Only one patient (10%) was anticoagulated with heparin throughout extracorporeal membrane oxygenation support. Eighty percent of patients required continuous venous-venous hemofiltration. Three patients (30%) developed persistent hypoxemia, which was corrected using higher positive end-expiratory pressure, higher inspired oxygen fractions, recruitment maneuvers, and nitric oxide. The median time on extracorporeal membrane oxygenation support was five (range 3–32) days. The median length of the hospital stay was 31 (range 3-97) days. Four patients (40%) survived to 60 days, and they were free from renal replacement therapy and oxygen support.CONCLUSIONS:The use of extracorporeal membrane oxygenation support in severely ill patients is possible in the presence of a structured team. Efforts must be made to recognize the necessity of extracorporeal respiratory support at an early stage and to prompt activation of the extracorporeal membrane oxygenation team.

The Effect of Hypopnea on Low-Pressure Pulmonary Edema

The effects of the mechanical factors involved in ventilation on pulmonary edema are only partially understood. To clarify the effect of ventilation on the adult respiratory distress syndrome (ARDS), we examined the effect of reducing rate and tidal volume on oleic acid-induced low-pressure pulmonary edema in dogs, hypothesizing that hypopnea would reduce lung edema. We placed the experimental animals on venous-venous extracorporeal membrane oxygenation (ECMO) for CO2 clearance and oxygenation 1 h after the injury. This allowed reduction of the ventilatory rate from 17.2 +/- 4.8 to 3.3 +/- 0.8 breaths/min and tidal volume from 20 to 16 ml/kg, effectively resting the injured lung. After 5 h of hypopnea there was no reduction in edema by gravimetric or extravascular thermal volume measurements. The ECMO-facilitated hypopnea reduced airway pressure and pulmonary artery pressure while improving arterial oxygen saturation but increased venous admixture. These results suggest that there may be a supportive role for ECMO-assisted hypopnea, but there was no direct beneficial effect of hypopnea on edema.