Elena Maggioni

Favourable survival of in-hospital compared to out-of-hospital refractory cardiac arrest patients treated with extracorporeal membrane oxygenation: An Italian tertiary care centre experience

OBJECTIVE Extracorporeal membrane oxygenation (ECMO) support has been suggested to improve the survival rate in patients with refractory in- and out-of-hospital cardiac arrest (IHCA and OHCA). The aim of our study is to report our experience with ECMO in these patients. DESIGN Retrospective, single-centre, observational study. PATIENTS From January 2006 to February 2011 we studied 42 patients (31 males) with refractory cardiac arrest. MEASUREMENT AND MAIN RESULTS ECMO implantation was successful in 38 (90%) of the 42 patients. ECMO support was positioned: three times (8%) in the operating room, six (16%) in the cardiac surgery intensive care unit, 21 (55%) in the emergency room, five (13%) in the catheterisation laboratory and three (8%) in the general ward. A total of 14 IHCA (58%) and three OHCA (16%) patients were weaned from ECMO (p<0.05). Eleven IHCA (46%) and one OHCA (5%, p<0.05) patients were discharged from intensive care unit (ICU). Among IHCA patients, 10 were alive at 6 months, nine of whom (38%) with good neurological outcome. Among OHCA patients weaned from ECMO, one was alive at 6 months with good neurological outcome (5%, p<0.05 vs. IHCA). CONCLUSIONS ECMO support should be considered as a resuscitation alternative in selected patients. More specifically, patients with witnessed IHCA benefit more from ECMO treatment compared to those who experience an out-of-hospital cardiac arrest.

Percutaneous left-heart decompression during extracorporeal membrane oxygenation: an alternative to surgical and transeptal venting in adult patients.

Extracorporeal membrane oxygenation (ECMO) is often applied for acute cardiorespiratory failure. Left ventricular distension can compromise recovery of the failing heart. To overcome this complication, we describe a new technique to decompress the left heart through the insertion of a venting cannula in the pulmonary artery. A 43-year-old woman was connected to ECMO for refractory cardiogenic shock after left pneumonia and severe sepsis. Transesophageal echocardiography (TEE) revealed a large intraventricular clot. A 15F venous cannula was placed percutaneously in the pulmonary artery and connected to the venous limb of the ECMO circuit to decompress the left heart, and to prevent left ventricular ejection and potential embolization. After myocardial recovery, when the thrombus was judged as stable, the patient was weaned, and ECMO was removed on day 16. The patient was discharged from the cardiac surgery intensive care unit on day 30 and subsequently had an uneventful recovery. This new percutaneous approach represent a feasible and effective method to vent the left heart during ECMO, when it becomes necessary to reduce wall tension or to prevent ejection.

Extracorporeal membrane oxygenation to support adult patients with cardiac failure: predictive factors of 30-day mortality

Adult patients supported on extracorporeal membrane oxygenation (ECMO) are very sick and many complications are often present in each single patient; therefore, it is not always easy to find some risk factors that can predict the early outcome. This retrospective study reports our experience in ECMO support treatment in adult cardiac patients suffering from cardiac failure (CF) in which one or more predictive factors of 30-day mortality were analyzed. Between January 2002 and August 2009, 42 consecutive adult cardiac patients with cardiogenic shock (mean age 64.3+/-11.3 years) were supported on ECMO for >2 days. They were divided into patients who had a survival <30 days (n=20) and patients who survived >30 days (n=22). Twenty-nine patients (69%) survived on ECMO. Sixteen patients were discharged with a survival rate of 38.1%. The overall mean ECMO duration was 7.9+/-5.3 days. The following variables were significantly different between the two groups: number of platelets and packed red blood cells (PRBCs) transfused per day during ECMO (P=0.002 and P=0.003), blood lactate levels 48 h and 72 h after the initiation of ECMO (P=0.01 and P=0.04), indexed blood flow after 48 h and 72 h (P=0.01 and P<0.0001), liver failure (P=0.001) and multiorgan failure (P=0.002). Stepwise logistic regression identified that blood lactate levels at 48 h and number of PRBCs transfused were associated with 30-day mortality [P=0.019, odds ratio (OR) =2.16; 95% confidence interval (CI)=1.13-4.14 and P=0.008, OR=1.08; 95% CI=1.02-1.14, respectively]. The predicted probability of mortality would be 52% when blood lactate levels are >3 mmol/l after 48 h. The blood lactate level at 48 h and PRBCs transfused per day can be considered as important parameters to predict the mortality in adult cardiac patients supported by ECMO for CF.

Extracorporeal membrane oxygenation with a poly-methylpentene oxygenator (Quadrox D). The experience of a single Italian centre in adult patients with refractory cardiogenic shock.

Although microporous polypropylene hollow fiber oxygenators are standard devices used for extracorporeal membrane oxygenation (ECMO), they have limitations such as development of plasma leakage. Poly-methylpentene (PMP) is a new material used for the last generation of oxygenators. We reviewed our experience with a new PMP oxygenator (Quadrox D) and a centrifugal pump (RotaFlow) used to support adult patients with refractory cardiogenic shock. Between January 2000 and April 2007, 25 patients required ECMO for primary or postcardiotomy cardiogenic shock. Eighteen patients were analyzed [mean age 60.2 years; 11 (61%) men; 7 (39%) women]. Nine patients (50%) suffered primary cardiogenic shock. Cardiopulmonary resuscitation was applied in 11 patients (61%) with a mean duration time of 31.5 minutes. Mean ECMO duration time was 7.1 ± 6.3 days (range, 1–27 days). Intra-aortic balloon pump was used in 13 patients (72.2%) with a mean duration time of 7.7 ± 5 (range, 2–17 days). Twelve patients (66.7%) survived on ECMO and five patients (27.8%) were discharged. Our results indicate the PMP oxygenator and the centrifugal pump provided acceptable results in terms of surviving on ECMO and discharge. Patients with an initial catastrophic hemodynamic status could benefit by means of a rapid institution of ECMO with PMP oxygenators.

Role of absolute lung volume to assess alveolar recruitment in acute respiratory distress syndrome patients.

Objective:It is commonly assumed that lung volume at zero end-expiratory pressure (functional residual capacity) is not affected by positive end-expiratory pressure (PEEP) even in presence of alveolar recruitment, and it is often ignored when measuring lung recruitment by pressure-volume curves. Aim of the study was to investigate the effect of PEEP on functional residual capacity, and quantify the error of considering equal functional residual capacity in measuring alveolar recruitment. Design:Interventional human study. Setting:A 10-bed general intensive care unit in a university hospital. Patients:Ten sedated, curarized, mechanically ventilated acute respiratory distress syndrome patients. Interventions:Three levels of PEEP (5, 10, and 15 cm H2O), were randomly applied, for 1 hr each. Measurements and Main Results:At each PEEP we obtained a pressure-volume curve, the volume expired from PEEP to zero pressure (PEEP related lung volume) and functional residual capacity by helium dilution method. Functional residual capacity increased at increasing PEEP levels. Functional residual capacity was 507 ± 292, 607 ± 311, and 681 ± 312 ml (p < .05), respectively, at PEEP 5, 10, and 15 cm H2O. Pressure-volume curves were aligned starting from PEEP related lung volume (relative volume method) or from end-expiratory lung volume at PEEP (absolute volume method). Recruitment was measured as vertical distance of pressure-volume curves at 20 cm H2O airway pressure. The relative volume method led to underestimation of recruitment (43 ± 28% and 35 ± 18 %, respectively, at PEEP 10 and 15). Conclusions:Functional residual capacity is affected by PEEP. Ignoring this effect leads to relevant underestimation of alveolar recruitment as measure by pressure-volume curve displacement.

Effects of extracorporeal cardiopulmonary resuscitation on neurological and cardiac outcome after ischaemic refractory cardiac arrest

Background: Extracorporeal cardiopulmonary resuscitation is increasingly recognised as a rescue therapy for refractory cardiac arrest, nevertheless data are scanty about its effects on neurologic and cardiac outcome. The aim of this study is to compare clinical outcome in patients with cardiac arrest of ischaemic origin (i.e. critical coronary plaque during angiography) and return of spontaneous circulation during conventional cardiopulmonary resuscitation vs refractory cardiac arrest patients needing extracorporeal cardiopulmonary resuscitation. Moreover, we tried to identify predictors of survival after successful cardiopulmonary resuscitation. Methods: We enrolled 148 patients with ischaemic cardiac arrest admitted to our hospital from 2011–2015. We compared clinical characteristics, cardiac arrest features, neurological and echocardiographic data obtained after return of spontaneous circulation (within 24 h, 15 days and six months). Results: Patients in the extracorporeal cardiopulmonary resuscitation group (n=63, 43%) were younger (59±9 vs 63±8 year-old, p=0.02) with lower incidence of atherosclerosis risk factors than those with conventional cardiopulmonary resuscitation. In the extracorporeal cardiopulmonary resuscitation group, left ventricular ejection fraction was lower than conventional cardiopulmonary resuscitation at early echocardiography (19±16% vs 37±11 p<0.01). Survivors in both groups showed similar left ventricular ejection fraction 15 days and 4–6 months after cardiac arrest (46±8% vs 49±10, 47±11% vs 45±13%, p not significant for both), despite a major extent and duration of cardiac ischaemia in extracorporeal cardiopulmonary resuscitation patients. At multivariate analysis, the total cardiac arrest time was the only independent predictor of survival. Conclusions: Extracorporeal cardiopulmonary resuscitation patients are younger and have less comorbidities than conventional cardiopulmonary resuscitation, but they have worse survival and lower early left ventricular ejection fraction. Survivors after extracorporeal cardiopulmonary resuscitation have a neurological outcome and recovery of heart function comparable to subjects with return of spontaneous circulation. Total cardiac arrest time is the only predictor of survival after cardiopulmonary resuscitation in both groups.

Safe ECMO femoral decannulation by placement of inferior vena cava filter via internal jugular vein.

Veno-arterial extracorporeal membrane oxygenation (ECMO) is a lifesaving treatment in patients with cardiogenic shock or cardiac arrest caused by massive pulmonary embolism. In these patients, positioning an inferior vena cava filter is often advisable, especially if deep venous thrombosis is not resolved at the time of the ECMO suspension. Moreover, in ECMO patients, a high incidence of deep venous thrombosis at the site of venous cannulation has been reported, and massive pulmonary embolism following ECMO decannulation has been described. Nonetheless, an inferior vena cava filter cannot be positioned as long as an ECMO cannula is inside the inferior vena cava. Thus, we developed a strategy to allow placement of an inferior vena cava filter through the internal jugular concurrently with the removal of the femoral venous ECMO cannula. In two women supported by veno-arterial ECMO for cardiac arrest secondary to pulmonary embolism, this novel approach allowed for safe ECMO decannulation.

ECMO for Refractory Cardiac Arrest

Sudden cardiac arrest is a potentially catastrophic event with an extremely high mortality rate. The poor prognosis is related to many factors linked to both the time before the return of spontaneous circulation and the care in the post-resuscitation period. The “life-support chain” concept and the continuous update of international guidelines over time improved the care of these patients in many aspects but with a modest impact on the final outcome. Extracorporeal support of the circulation was first attempted in the 1960s with primitive devices and uncertain utility. Advances in technology made possible the development of the “extracorporeal life-support” concept, and the extended application of ECLS allowed progressively improved outcomes. Extracorporeal circulation remains an uncommon therapy for highly selected patients, but we believe that it represents an important and valuable therapeutic option in patients suffering cardiac arrest, when this is performed by a well-trained team, on top of state-of-the-art conventional management.