Echocardiography for patients undergoing extracorporeal cardiopulmonary resuscitation: a primer for intensive care physicians

Non-invasive assessment of left ventricular contractility by myocardial work index in veno-arterial membrane oxygenation patients: rationale and design of the MIX-ECMO multicentre observational study

Introduction and aims

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is an increasingly utilized therapeutic choice in patients with cardiogenic shock, however, high complication rate often counteracts with its beneficial cardiopulmonary effects. The assessment of left ventricular (LV) function in key in the management of this population, however, the most commonly used measures of LV performance are substantially load-dependent. Non-invasive myocardial work is a novel LV functional measure which may overcome this limitation and estimate LV function independent of the significantly altered loading conditions of VA-ECMO therapy. The Usefulness of Myocardial Work IndeX in ExtraCorporeal Membrane Oxygenation Patients (MIX-ECMO) study aims to examine the prognostic role of non-invasive myocardial work in VA-ECMO-supported patients.

Methods

The MIX-ECMO is a multicentric, prospective, observational study. We aim to enroll 110 patients 48-72 h after the initiation of VA-ECMO support. The patients will undergo a detailed echocardiographic examination and a central echocardiography core laboratory will quantify conventional LV functional measures and non-invasive myocardial work parameters. The primary endpoint will be failure to wean at 30 days as a composite of cardiovascular mortality, need for long-term mechanical circulatory support or heart transplantation at 30 days, and besides that other secondary objectives will also be investigated. Detailed clinical data will also be collected to compare LV functional measures to parameters with established prognostic role and also to the Survival After Veno-arterial-ECMO (SAVE) score.

Conclusions

The MIX-ECMO study will be the first to determine if non-invasive myocardial work has added prognostic value in patients receiving VA-ECMO support.

Veno-venous extracorporeal membrane oxygenation (VV ECMO) cannula malposition identified with point-of-care ultrasound

BACKGROUND

Point-of-care ultrasound (POCUS) has become a mainstay in the evaluation of critically ill patients in the intensive care unit (ICU). ECMO patients are susceptible to complications during prolonged ICU stay, including cannula malposition, which has deleterious consequences. Although the literature surrounding utility of ultrasound on ECMO patients is expansive, direct comparison between radiographic imaging versus ultrasound for identification of cannula malposition is lacking.

CASE PRESENTATION

The authors identified four patients with cannula malposition discovered through POCUS that was missed on routine radiographic imaging. Identification and correction of malposition changed their ECMO course.

CONCLUSION

This case series is the first in literature demonstrating that ultrasound may be superior to radiographic images for ECMO cannula malposition. Further investigation into this subject is warranted.

Monitoring during extracorporeal membrane oxygenation

PURPOSE OF REVIEW

Extracorporeal membrane oxygenation (ECMO) offers advanced mechanical support to patients with severe acute respiratory and/or cardiac failure. Ensuring an adequate therapeutic approach as well as prevention of ECMO-associated complications, by means of timely liberation, forms an essential part of standard ECMO care and is only achievable through continuous monitoring and evaluation. This review focus on the cardiorespiratory monitoring tools that can be used to assess and titrate adequacy of ECMO therapy; as well as methods to assess readiness to wean and/or discontinue ECMO support.

RECENT FINDINGS

Surrogates of tissue perfusion and near infrared spectroscopy are not standards of care but may provide useful information in select patients. Echocardiography allows to determine cannulas position, evaluate cardiac structures, and function, and diagnose complications. Respiratory monitoring is mandatory to achieve lung protective ventilation and identify early lung recovery, surrogate measurements of respiratory effort and ECMO derived parameters are invaluable in optimally managing ECMO patients.

SUMMARY

Novel applications of existing monitoring modalities alongside evolving technological advances enable the advanced monitoring required for safe delivery of ECMO. Liberation trials are necessary to minimize time sensitive ECMO related complications; however, these have yet to be standardized.

[Out-of-hospital cardiac arrest: current diagnostic and therapeutical concepts]

Out-of-hospital circulatory arrest represents a challenging situation in emergency medicine even until today. Despite optimal emergency care and clinical treatment pathways, we are faced with a mortality rate above 90 %. It is possible to improve the survival rate to more than 40 % under ideal clinical and preclinical conditions. Thus, more people's life could be saved by standardized SOPs and networks in emergency medicine. About 14.000 preclinical resuscitation cases are reported in Germany per year. The prognosis out-of-hospital circulatory arrest patients is determined by best preclinical treatment including early resuscitation by bystanders. However, ethical considerations for not performing cardiopulmonary resuscitation include comorbidities, advanced age, and prognostic markers of intensive care medicine like lactate level or neuron-specific enolase. Since myocardial infarction is the underlying disease in about 3 quarters of acute circulatory arrest cases, early angiography and coronary revascularization is of upmost importance. In addition, it is essential to provide hemodynamic stabilization for prevention of multiorgan dysfunction syndrome. Neuroprotection by therapeutic hypothermia may further help to improve survival and quality of life. Mechanical circulatory support devices may be considered adjunct to pharmacological measures for hemodynamic stabilization. Due to lack of evidence, these devices are currently under evaluation and prospectively randomized trials. We expect new treatment algorithms for optimal care of these high-risk patients in the near future.

[Recommendations for extracorporeal cardiopulmonary resuscitation (eCPR) : Consensus statement of DGIIN, DGK, DGTHG, DGfK, DGNI, DGAI, DIVI and GRC]

Extracorporeal cardiopulmonary resuscitation (eCPR) may be considered as a rescue attempt for highly selected patients with refractory cardiac arrest and potentially reversible etiology. Currently there are no randomized, controlled studies on eCPR, and valid predictors of benefit and outcome which might guide the indication for eCPR are lacking. Currently selection criteria and procedures differ across hospitals and standardized algorithms are lacking. Based on expert opinion, the present consensus statement provides a proposal for a standardized treatment algorithm for eCPR.