Extracorporeal membrane oxygenation as an alternative to ventilation

Mucosal bleeding while on venovenous extracorporeal membrane oxygenation in the setting of vitamin C deficiency

A major complication with extracorporeal membrane oxygenation (ECMO) is bleeding which can occur in up to 40% of cases and can be life-threatening. Minor bleeding may be overlooked and under-reported. While some of the underlying mechanisms such as platelet injury and anticoagulation therapy have been identified, several other factors are still under-researched. Here, we describe a unique case of a subtle mucosal membrane bleeding that is found to be associated with vitamin C deficiency while on treatment with ECMO. Investigating vitamin C levels may be useful in understanding causes of bleeding in some patients on ECMO therapy, particularly if there are risk factors for malnutrition.

Tracheostomy as a bridge to spontaneous breathing and awake-ECMO in non-transplant surgical patients

AIMS

The tracheostomy is a frequently used procedure for the respiratory weaning of ventilated patients allows sedation free ECLS use in awake patient. The aim of this study is to assess the possibility and highlight the benefits of lowering the impact of sedation in surgical non-transplant patients on ECLS. The specific objective was to investigate the use of tracheostomy as a bridge to spontaneous breathing on ECLS.

METHODS AND RESULTS

Of the 95 patients, 65 patients received a tracheostomy, and 5 patients were admitted with a tracheostoma. One patient was cannulated without intubation, one is extubated during ECLS course after 48 hours. 4 patients were extubated after weaning and the removal of ECLS. 19 patients died before the indication to tracheostomy was given.

CONCLUSION

Tracheostomy can bridge to spontaneous breathing and awake-ECMO in non-transplant surgical patients. The "awake ECMO" strategy may avoid complications related to mechanical ventilation, sedation, and immobilization and provide comparable outcomes to other approaches for providing respiratory support.

Amniotic Fluid Embolism: Using the Medical Staff Process to Facilitate Streamlined Care

Amniotic fluid embolism (AFE) is a catastrophic consequence of labor and delivery that often results in maternal and neonatal death. These poor outcomes are related largely to the rarity of the event in a population overwhelmingly biased by overall good health. Despite the presence of national AFE registries, there are no published algorithmic approaches to its management, to our knowledge. The purpose of this article is to share a care pathway developed by a multidisciplinary group at a community teaching hospital. Post hoc analysis of a complicated case of AFE resulted in development of this pathway, which addresses many of the major consequences of AFE. We offer this algorithm as a template for use by any institution willing to implement a clinical pathway to treat AFE. It is accompanied by the remarkable case outcome that prompted its development.

[Veno-arterial extracorporeal membrane oxygenation. Indications, limitations and practical implementation]

Due to the technical advances in pumps, oxygenators and cannulas, veno-arterial extracorporeal membrane oxygenation (va-ECMO) or extracorporeal life support (ECLS) has been widely used in emergency medicine and intensive care medicine for several years. An accepted indication is peri-interventional cardiac failure in cardiac surgery (postcardiotomy low cardiac output syndrome). Furthermore, especially the use of va-ECMO for other indications in critical care medicine, such as in patients with severe sepsis with septic cardiomyopathy or in cardiopulmonary resuscitation has tremendously increased. The basic indications for va-ECMO are therapy refractory cardiac or cardiopulmonary failure. The fundamental purpose of va-ECMO is bridging the function of the lungs and/or the heart. Consequently, this support system does not represent a causal therapy by itself; however, it provides enough time for the affected organ to recover (bridge to recovery) or for the decision for a long-lasting organ substitution by a ventricular assist device or by transplantation (bridge to decision). Although the outcome for bridged patients seems to be favorable, it should not be forgotten that the support system represents an invasive procedure with potentially far-reaching complications. Therefore, the initiation of these systems needs a professional and experienced (interdisciplinary) team, sufficient resources and an individual approach balancing the risks and benefits. This review gives an overview of the indications, complications and contraindications for va-ECMO. It discusses its advantages in organ transplantation and transport of critically ill patients. The reader will learn the differences between peripheral and central cannulation and how to monitor and manage va-ECMO.

Identification of acquired coagulation disorders and effects of target-controlled coagulation factor substitution on the incidence and severity of spontaneous intracranial bleeding during veno-venous ECMO therapy

Introduction:

Intracranial haemorrhage is a redoubtable complication during extracorporeal membrane oxygenation (ECMO) therapy. The underlying mechanisms of haemorrhagic diathesis are still not completely understood. This study was performed to evaluate a coagulation protocol for the regular analysis of acquired coagulation disorders and the systematic substitution of coagulation factors to reach predefined target values. We hypothesised that using this strategy would lead to the identification of acquired bleeding disorders which cannot be monitored with standard coagulation tests and that substitution of the respective factors in a target-controlled approach could have an impact on the incidence and severity of intracranial haemorrhage.

Methods:

A protocol for the analysis of acquired coagulation disorders and the subsequent administration of associated factor concentrates was introduced. Previously, coagulation management was mainly based on clinical bleeding signs as the trigger for the administration of blood products. In this investigation, nineteen consecutive patients before (control group) and twenty consecutive patients after the implementation of the protocol (intervention group) have been included in the study.

Results:

Eighty-eight percent of the patients developed factor XIII deficiency, 79% acquired von Willebrand syndrome, 40% fibrinogen deficiency and 54% of the patients showed a decline in platelet count >20% within the first 24 hours of ECMO therapy. In 6 out of 19 (31%) patients in the control group and in 2 patients out of 20 (10%) in the intervention group, intracranial haemorrhage was detected. Whilst 5 of 6 patients in the control group died because of fatal bleeding, both of the patients in the intervention group recovered with a favourable neurologic outcome.

Conclusions:

Veno-venous ECMO therapy leads to thrombocytopenia, factor XIII and fibrinogen deficiency as well as acquired von Willebrand syndrome. The implementation of a coagulation protocol including a standardized determination and target-controlled substitution of coagulation factors may have a beneficial impact on the incidence and severity of intracranial haemorrhage.

Extracorporeal membrane oxygenation

Extracorporeal membrane oxygenation (ECMO) is an advanced form of life support technology whereby venous blood is oxygenated outside of the body and returned to the patient. ECMO was initially used as last-resort rescue therapy for patients with severe respiratory failure. Over the last four decades, it has developed into a safe, standard therapy for newborns with progressive cardiorespiratory failure, as a resuscitation therapy after cardiac arrest, and in combination with other treatments such as hypothermia and various blood filtration therapies. ECMO has also become routine for children and adults with all forms of cardiogenic shock and is also routine in early graft failure after transplantation. The one area of ongoing debate is the role of ECMO in adults with hypoxemic respiratory failure. As ECMO equipment becomes safer, earlier use improves patient outcomes. Several modifications of the two basic venovenous and venoarterial ECMO systems are now occurring, as are many minor variations in cannulation strategies and systems of care for patients receiving ECMO. The indications and situations in which ECMO have been tried continue to change, and ECMO for sub-acute and chronic illnesses is now commonplace, as is the use of ECMO in patients with clinical problems previously regarded as contraindications, such as sepsis, malignancy, and immunosuppression.