A systematic review of effectiveness and economic evaluation of Cardiohelp and portable devices for extracorporeal membrane oxygenation (ECMO)

A New Multifunction Oxygenator With a Dual-Chamber Gas Exchanger to Reduce Dependence on Oxygen Supply

Although extracorporeal membrane oxygenation (ECMO) systems have been used to provide temporary support for patients with severe respiratory or cardiac failure, they are often bedridden, in part because of their bulky size which relies solely on an unlimited source of wall oxygen. However, there is an unmet clinical need for ambulatory ECMO which necessitates downsizing the ECMO system. We sought to develop a new oxygenator to reduce the dependence on the oxygen supply source. The proposed oxygenator features a dual-chamber gas exchangers, with one chamber primarily responsible for carbon dioxide removal using ambient air and a subsequent chamber primarily responsible for oxygen transfer using pure oxygen. Computational fluid dynamics was used to analyze the blood flow field to avoid adverse stagnation and optimize gas exchange performance. Bovine blood was used for in vitro gas transfer test. This new oxygenator demonstrated the capability to provide adequate respiratory support (both carbon dioxide removal and oxygen transfer) to adult patients at blood rate of 4-6 L/min with an oxygen supply of only 2 L/min. The reduced use of oxygen with this new oxygenator may pave the way for the development of potable ECMO systems.

Different ECLS Pump Configurations for Temporary Right Ventricular Assist Device in LVAD Patients: A Retrospective Case-Control Study

BACKGROUND

Acute right ventricular failure is a critical complication after left ventricular assist device (LVAD) implantation, often managed with a temporary paracorporeal right ventricular assist device (RVAD). This study examined three extracorporeal life support (ECLS) systems regarding mortality, bleeding complications, and intensive care unit (ICU) stay duration.

METHODS

This monocentric, retrospective case-control study included all patients receiving LVAD with paracorporeal RVAD between 2009 and 2020. Three patient groups were formed: CentrimagTM (A), CardiohelpTM (B), and DeltastreamTM (C).

RESULTS

A total of 245 patients were included. Preoperative parameters were similar between the CentrimagTM and DeltastreamTM groups, but CardiohelpTM patients had worse Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) Scores (A: 1.7 ± 0.8, B: 1.36 ± 0.5, C: 1.9 ± 0.9; p < 0.05). In-hospital death rates were A: 61 (41.8%), B: 15 (32.6%), C: 29 (54.7%); p < 0.05, and reoperation due to bleeding rates were A: 32 (21.9%), B: 8 (17.4%), C: 25 (47.2%); p < 0.05, with the DeltastreamTM group showing the highest rates. This group also had increased thrombocyte consumption and prolonged ICU stays.

CONCLUSIONS

Temporary RVADs lead to bleeding complications, affecting patient outcomes. The DeltastreamTM group had significantly higher bleeding complications, likely due to high pump revolution rates and thrombocyte decline. Due to the study's retrospective nature and complex patient profiles, these interesting findings should be validated in future studies.

Prognostic impact of lung computed tomography density in cardiogenic shock patients with veno-arterial extracorporeal membrane oxygenation

BACKGROUND

Pulmonary complications often occur in patients receiving veno-arterial extracorporeal membrane oxygenation (VA ECMO). However, the prognostic impact of lung damage has not been fully elucidated.

METHODS

This single-center retrospective observational study targeted patients with cardiogenic shock who received VA ECMO between 2012 and 2021. This study included 65 patients who underwent chest computed tomography (CT) on VA ECMO, followed by escalation to central mechanical circulatory support (MCS) with left ventricular venting. The average density of lung CT images was measured using region-of-interest methods, and the primary endpoint was 180-day all-cause death after escalation to the central MCS.

RESULTS

Twenty-two patients (34%) developed 180-day all-cause death. According to the Cox regression analysis, age (hazard ratio [HR], 1.08; 95% confidence interval [CI], 1.03-1.14; p = 0.001), ischemic etiology (HR, 5.53; 95% CI, 2.09-14.62; p < 0.001), duration of VA ECMO support (HR, 1.19; 95% CI, 1.00-1.40; p = 0.045), and lung CT density (≥ -481 Hounsfield unit [HU]) (HR, 6.33; 95% CI, 2.26-17.72; p < 0.001) were independently associated with all-cause death. Receiver operating characteristic curve analysis determined that lung CT density ≥ -481 HU is an optimal cutoff value for predicting all-cause death (area under the curve [AUC], 0.72). The 180-day overall survival rate for patients with high lung CT density (≥ -481 HU) was significantly lower than that for those with low lung CT density (< -481 HU) (44.4% vs. 81.6%, respectively, p = 0.002).

CONCLUSIONS

Higher lung CT density could be a useful predictor of death in patients with VA ECMO requiring central MCS escalation.

Single-Center Experience Using the Cardiohelp System for Neonatal and Pediatric Extracorporeal Membrane Oxygenation

OBJECTIVES

Extracorporeal membrane oxygenation (ECMO) systems have continued to evolve and improve with the development of smaller and portable systems. The Cardiohelp (Maquet Getinge Cardiopulmonary AG, Rastatt, Germany) portable life support device is a compact ECMO system used widely in adults and for ECMO transport. Reports of its use in neonatal and pediatric centers remain limited. In this single-center retrospective review, we describe our institutional experience with the Cardiohelp.

DESIGN

Single-center retrospective review.

SETTING

Neonatal ICUs and PICUs in a tertiary-care children's hospital.

PATIENTS

Seventeen pediatric patients on ECMO.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Median (interquartile range, IQR) of patient age was 0.5 years (0-7 yr). Eleven of 17 patients were on veno-arterial ECMO, five on veno-venous ECMO, and one on veno-venoarterial ECMO. All veno-venous and veno-venoarterial runs ( n = 6) were accomplished with bicaval, dual-lumen cannulae. Median duration on Cardiohelp was 113 hours (IQR 50-140 hr). Median anti-Xa level for patients was 0.43 IU/mL (IQR 0.35-0.47 IU/mL), with median heparin dose of 23.6 U/kg/hr (IQR 17.6-28.1 U/kg/hr). Median plasma-free hemoglobin was 41.4 mg/dL (IQR 30-60 mg/dL). Circuit change was required in three cases. Fourteen patients survived ECMO, with 13 patients surviving to discharge.

CONCLUSIONS

We have used the Cardiohelp system to support 17 neonatal and pediatric ECMO patients, without complications. Further studies are warranted to compare complications, outcomes, and overall cost with other institutions and other existing ECMO systems.

Safety and Efficacy of a Novel Centrifugal Pump and Driving Devices of the OASSIST ECMO System: A Preclinical Evaluation in the Ovine Model

Background: Extracorporeal membrane oxygenation (ECMO) provides cardiopulmonary support for critically ill patients. Portable ECMO devices can be applied in both in-hospital and out-of-hospital emergency conditions. We evaluated the safety and biocompatibility of a novel centrifugal pump and ECMO device of the OASSIST ECMO System (Jiangsu STMed Technologies Co., Suzhou, China) in a 168-h ovine ECMO model.

Methods: The portable OASSIST ECMO system consists of the control console, the pump drive, and the disposable centrifugal pump. Ten healthy sheep were used to evaluate the OASSIST ECMO system. Five were supported on veno-venous ECMO and five on veno-arterial ECMO, each for 168 h. The systemic anticoagulation was achieved by continuous heparin infusion to maintain the activated clotting time (ACT) between 220 and 250 s. The rotary speed was set at 3,200–3,500 rpm. The ECMO configurations and ACT were recorded every 6 hours (h). The free hemoglobin (fHb), complete blood count, and coagulation action test were monitored, at the 6th h and every 24 h after the initiation of the ECMO. The dissection of the pump head and oxygenator were conducted to explore thrombosis.

Results: Ten sheep successfully completed the study duration without device-related accidents. The pumps ran stably, and the ECMO flow ranged from 1.6 ± 0.1 to 2.0 ± 0.11 L/min in the V-V group, and from 1.8 ± 0.1 to 2.4 ± 0.14 L/min in the V-A group. The anticoagulation was well-performed. The ACT was maintained at 239.78 ± 36.31 s, no major bleeding or thrombosis was observed during the ECMO run or in the autopsy. 3/5 in the V-A group and 4/5 in the V-V group developed small thrombus in the bearing pedestal. No obvious thrombus formed in the oxygenator was observed. The hemolytic blood damage was not significant. The average fHb was 0.17 ± 0.12 g/L. Considering hemodilution, the hemoglobin, white blood cell, and platelets didn't reduce during the ECMO runs.

Conclusions: The OASSIST ECMO system shows satisfactory safety and biocompatibility for the 168-h preclinical evaluation in the ovine model. The OASSIST ECMO system is promising to be applied in clinical conditions in the future.

Disposable Component Selection in Extracorporeal Life Support: A Cost Analysis

Extracorporeal life support (ECLS) is a resource-intensive technology. Disposable components are modifiable through device selection. Cost analysis tools are needed to inform cost-conscious device selection. We generated a disposable cost analysis to forecast estimated costs of device disposables that included an assumption table, net present value (NPV) analysis, and sensitivity analysis to examine device disposable costs over 5 years with different case volumes and device mixes. To demonstrate the function of the analysis, we included four device options using the following assumptions: 100 cases in year 1, 2.5% case growth rate, 10% discount rate, and $5,000 incremental cost (Device 4 only). Using estimated device costs of $3,000, $12,000, $13,000, and $20,000 and device mix percentages of 65%, 8%, 25%, and 2% for Device 1, 2, 3, and 4, respectively, the 5 year unadjusted and NPV of disposable device costs were $3,691,000 and $2,765,000, respectively. The sensitivity analysis incorporated six separate models with different device mix percentages. The highest and lowest estimated costs were found in Model F (75% Device 3 and 25% Device 4; NPV = $6,64,400) and Model B (100% Device 1; NPV = 1,246,000) respectively. Extracorporeal life support programs may apply this disposable cost analysis tool to reduce programmatic costs.

Outcome of CentriMag™ extracorporeal mechanical circulatory support use in critical cardiogenic shock (INTERMACS 1) patients

Purpose

Prognosis of patients presenting with INTERMACS 1 critical cardiogenic shock is generally poor. The aim of our study was to investigate the results of CentriMag™ extracorporeal short-term mechanical circulatory support as a bridge to decision in patients presenting with critical cardiogenic shock in our unit.

Methods

We retrospectively analysed 63 consecutive patients from January 2005 to June 2017, who were treated with a CentriMag™ device at our institution as a bridge to decision. Patients requiring extracorporeal support for post-cardiotomy shock and for primary graft dysfunction after heart transplantation were excluded.

Results

Patients’ median age was 44 years (IQR 31–52, range 15.4–62.0) and 42 (67%) were male. Primary diagnosis at presentation was ischaemic cardiomyopathy (n = 24; 38.1%), viral myocarditis (n = 19; 30.2%), idiopathic dilated cardiomyopathy (n = 8; 12.7%), and others (n = 12; 19%). The median duration of support was 25 (IQR 9.5–56) days. A total of 7 (11%) patients were supported with peripheral veno-arterial (VA) extra corporeal membrane oxygenation (ECMO), 6 (9%) with central VA ECMO, 8 (13%) with left ventricular assist device (LVAD), 17 (27%) with biventricular assist device (BiVAD), and 25 (40%) with ECMO and then converted to BiVAD. Overall, 22 (34.9%) patients died while on CentriMag™ mechanical circulatory support. Complications included bleeding requiring reoperation/intervention in 24 (38%), renal failure requiring dialysis in 29 (46%), bacterial infections in 23 (37%), fungal infections in 15 (24%), critical limb ischaemia in 6 (10%), and stroke in 8 (13%). The overall survival to successful explant from CentriMag™ was 65.1% (n = 41) and survival to hospital discharge was 58.7% (n = 37). Of these, 10 (16%) had cardiac recovery and were successfully explanted, 20 (32%) were bridged to heart transplantation, 11 (17%) were bridged to long-term left ventricular assist device, 3 (4.7%) were later on transplanted, and 1 (1.6%) recovered to decommissioning. The 1-, 5-, and 10-year survival rates were 55%, 46%, and 23% respectively.

Conclusion

Our results demonstrate an excellent outcome with the use of the CentriMag™ device in this seriously ill population. Despite requiring multiple procedures, over 58% of patients were discharged from hospital with 5-year survival of 46%.