Neonatal Carotid Artery and Internal Jugular Vein Management Practices at Extracorporeal Membrane Oxygenation Decannulation: No Standard Approach

BACKGROUND

There are currently no commonly accepted standardized guidelines for management of cervical vessels at neonatal extracorporeal membrane oxygenation (ECMO) decannulation. This study investigates neonatal ECMO decannulation practices regarding management of the carotid artery and internal jugular vein, use of post-repair anticoagulation, and follow-up imaging.

METHODS

A survey was distributed to the 37 institutions in the Children's Hospitals Neonatal Consortium. Respondents reported their standard approach to carotid artery and internal jugular vein management (ligation or repair) at ECMO decannulation by their pediatric surgery and cardiothoracic (CT) surgery teams as well as post-repair anticoagulation practices and follow-up imaging protocols.

RESULTS

The response rate was 95%. Pediatric surgeons performed most neonatal respiratory ECMO cannulations (88%) and decannulations (85%), while all neonatal cardiac ECMO cannulations and decannulations were performed by CT surgeons. Pediatric surgeons overwhelmingly ligate both vessels (90%) while CT surgeons typically repair both vessels at decannulation (83%). Of the responding centers that repair, 28% (7) have a standard anticoagulation protocol after neck vessel repair. While 52% (13) of centers routinely image cervical vessel patency at least once post repair, most do not subsequently repeat neck vessel imaging.

CONCLUSIONS

Significant practice differences exist between pediatric and CT surgeons regarding the approach to cervical vessels at neonatal ECMO decannulation. For those centers that do repair the vessels there is little uniformity in post-repair anticoagulation or imaging protocols. There is a need to develop standardized cervical vessel management guidelines for neonatal ECMO patients and to study their impact on both short- and long-term outcomes.

LEVEL OF EVIDENCE

IV.

Neonatal venoarterial and venovenous ECMO

ECMO remains an important support tool in the treatment of neonates with reversible congenital cardiopulmonary diseases. There are specific circumstances that call for either venoarterial (VA) or venovenous (VV) ECMO in neonates. While limited by the infant's the size and gestational age, ECMO can confer exceptional survival rates to a number of neonates who can often develop without devastating complications. However, it remains a labor and time intensive endeavor, which may be impractical or unattainable in resource-limited environments. While adult and pediatric ECMO indications and equipment options have expanded in recent years, neonatal ECMO continues to be a niche subspecialty requiring specific expertise and technical skill, especially considering the ever-changing neonatal physiology in the setting of cardiopulmonary support. It is critical to recognize the unique approaches to cannulation options, imaging, vessel management, anticoagulation, and monitoring protocols to achieve optimal outcomes. Thus, it becomes nearly impossible to separate the role of pediatric surgeons from the continuous involvement with and management of neonatal ECMO patients. This necessitates that pediatric surgeons in ECMO centers continue to hone their expertise and remain heavily involved in neonatal ECMO. This section reviews the most critical current approaches and unresolved controversies in neonatal ECMO with special attention to the practical aspects and decisions a surgeon faces in initiation and termination of neonatal ECMO.

Updates in Neonatal Extracorporeal Membrane Oxygenation and the Artificial Placenta

Extracorporeal life support, initially performed in neonates, is now commonly used for both pediatric and adult patients requiring pulmonary and/or cardiac support. Data suggests the clinical feasibility of Extracorporeal Membrane Oxygenation for premature infants (29-33 weeks estimated gestational age [EGA]). For extremely premature infants less than 28 weeks EGA, an artificial placenta has been developed to recreate the fetal environment. This approach is investigational but clinical translation is promising. In this article, we discuss the current state and advances in neonatal and "preemie Extracorporeal Membrane Oxygenation" and the development of an artificial placenta and its potential use in extremely premature infants.

Neonatal extra corporeal membrane oxygenation

Extracorporeal life support (ECLS) has been proven to be very useful in the neonatal period. For reversible respiratory and cardiac disorders, when maximal conventional measures have failed to provide life support, extracorporeal membrane oxygenation (ECMO) becomes the treatment of choice. The indications, contra-indications for ECMO, optimization of the care prior to embracing ECMO, cannulation techniques, daily management of ECMO from the practical standpoint, weaning and decannulation, complications, and special circumstances in neonatal period have been described. The follow-up of neonatal ECMO and various system manifestations necessitating careful review will be highlighted.

Extra-Corporeal Membrane Oxygenation for Neonatal Respiratory Support

To review our experience with Extra-Corporeal Membrane Oxygenation (ECMO) for respiratory support in neonates. From 1989 to 2018 2114 patients underwent respiratory ECMO support, with 764 (36%) neonates. Veno-Venous (V-V) cannulation was used in 428 (56%) neonates and Veno-Arterial (V-A) in 336 (44%). Historically V-V ECMO was our preferred modality, but due to lack of suitable cannula in the last 7 years V-A was used in 209/228 (92%) neonates. Mean and inter-quartile range of ECMO duration was 117 hours (inter-quartile range 90 to 164 hours). Overall 724 (95%) neonates survived to ECMO decannulation, with 640 (84%) hospital discharge. Survival varied with underlying diagnosis: meconium aspiration 98% (354/362), persistent pulmonary hypertension 80% (120/151), congenital diaphragmatic hernia 66% (82/124), sepsis 59% (35/59), pneumonia 86% (6/7), other 71% (43/61). Survival was 86% with V-V and 80% with V-A cannulation, better than ELSO Registry with 77% V-V and 63% V-A. Major complications: cerebral infarction/hemorrhage in 4.7% (31.1% survival to discharge), renal replacement therapy in 17.6% (58.1% survival to discharge), new infection in 2.9%, with negative impact on survival (30%). Following a circuit design modification and subsequent reduction in heparin requirement, intracerebral hemorrhage decreased to 9/299 (3.0%) radiologically proven cerebral infarction/hemorrhage. We concluded (1) outcomes from neonatal ECMO in our large case series were excellent, with better survival and lower complication rate than reported in ELSO registry. (2) These results highlight the benefits of ECMO service in high volume units. (3) The similar survival rate seen in neonates with V-A and V-V cannulation differs from the ELSO register; this may reflect the change in cannulation enforced by lack of suitable V-V cannula and all neonates undergoing V-A cannulation.

Outcomes and associated ethical considerations of long-run pediatric ECMO at a single center institution

PURPOSE

Survival of neonatal and pediatric patients undergoing extracorporeal membrane oxygenation (ECMO) ≥ 21 days has not been well described. We hypothesized that patients would have poor survival and increased long-term complications.

METHODS

Retrospective, single center, review and case analysis. Tertiary-care university children's hospital including neonatal, pediatric and cardiac intensive care units. After institutional review board approval, the charts of all patients < 18 years of age undergoing ECMO for ≥ 21 continuous days were performed, and they were compared to comparative patients undergoing shorter runs. Overall survival, incidence of complications, and post-discharge recovery were recorded.

RESULTS

Overall survival was 36% in patients undergoing ≥ 21 days of ECMO (N = 14). 5/8 patients with cardiopulmonary failure from acquired etiologies survived versus 0/6 patients with congenital anomalies. 1/5 survivors achieved complete recovery with no neurologic deficits. The remaining survivors suffer from multiple medical and neurodevelopmental morbidities.

CONCLUSION

ECMO support for ≥ 21 days is associated with poor survival, particularly in neonates with congenital anomalies. Long-term outcomes for survivors ought to be carefully weighed and discussed with parents given the high incidence of neurologic morbidities in this population.

Extracorporeal membrane oxygenation in infants with congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is a severe congenital anomaly which impairs normal pulmonary development leading to acute and chronic respiratory failure, pulmonary hypoplasia, pulmonary hypertension, and mortality. CDH is the most common non-cardiac indication for neonatal ECMO. Prenatal and postnatal predictors of CDH severity aid in patient selection. Centers vary in preferred mode of ECMO and timing of CDH repair. Survivors of severe CDH with ECMO are at risk for long-term sequelae including neurodevelopmental delays.

Special equipment considerations for neonatal ECMO

Extracorporeal membrane oxygenation (ECMO) for neonates is applied routinely at major children's hospitals around the world. While the practice seems routine, the peculiar physiology of the small human imposes particular constraints on selection of equipment, performance of the circuit, and risks to the child. The physiology of small patients and physics of circuit elements leave many areas opaque and far from optimal, but still allow assembly of a set of useful heuristics for good practice. Here, we examine individual mechanical components of the ECMO circuit with attention to selection, pitfalls, and peculiarities of each when applied to the neonate.

An overview of medical ECMO for neonates

Extracorporeal membrane oxygenation (ECMO), a life-saving therapy for respiratory and cardiac failure, was first used in neonates in the 1970s. The indications and criteria for ECMO have changed over the years, but it continues to be an important option for those who have failed other medical therapies. Since the Extracorporeal Life Support Organization (ELSO) Registry was established in 1989, more than 29,900 neonates have been placed on ECMO for respiratory failure, with 84% surviving their ECMO course, and 73% surviving to discharge or transfer. In this chapter, we will review the basics of ECMO, patient characteristics and criteria, patient management, ECMO complications, special uses of neonatal ECMO, and patient outcomes.

Simulation for neonatal extracorporeal membrane oxygenation teams

Extracorporeal membrane oxygenation (ECMO) is a highly technical and complex method of life support. Patient and circuit emergencies on ECMO are rare, but in these cases, prompt and correct actions to address the crisis are needed to prevent morbidity and mortality. ECMO simulation programs have gained popularity in recent years, as they provide a standardized educational experience for all members of the inter-professional care team. In addition to providing a context in which to solidify knowledge of ECMO support, participants are also able to focus on vital technical and behavioral skills that are not highlighted in other training methodologies. ECMO simulation can also be used for quality improvement, clinical and educational research, and assessment/credentialing. Multi-organizational international collaboratives have formed, and are working to standardize ECMO education training across institutions; simulation will play an essential role in this process.