Duplex Analysis of Cannulated Vessels in Peripheral Veno-Arterial Extracorporeal Membrane Oxygenation

Best Practices for Vessel Management in Pediatric Extracorporeal Membrane Oxygenation Cannulation, Decannulation, and Follow-up: A Narrative Review

Extracorporeal membrane oxygenation (ECMO) to support neonates and children with cardiopulmonary failure was first described in the 1970s, since which time its use has expanded to an increasingly complex and heterogenous pediatric population. Despite preserved survival outcomes, complications of ECMO use, including iatrogenic vascular injury, are common. Here, we provide a brief overview of the epidemiology of pediatric ECMO and associated vascular complications; describe common peripheral cannulation equipment and techniques, trends in cannulation and decannulation strategies, and respective incidence of vascular complications; and review existing evidence for best practices in cannula site selection, cannulation technique, decannulation strategies, and management of vascular complications, with the goal of providing a comprehensive review for interventionalists involved in the care of pediatric ECMO patients. Areas of wide practice variation in vessel management-application of vessel-sparing cervical venoarterial cannulation, the use of distal perfusion catheters in femoral arterial cannulation, and best practices for percutaneous single-lumen venovenous cannulation, as examples-areas of focus for future research, and the potential role of vascular surgeons and other subspecialty proceduralists in the care of pediatric ECMO patients are highlighted. LEVEL OF EVIDENCE: V.

Evolution of distal limb perfusion management in adult peripheral venoarterial extracorporeal membrane oxygenation with femoral artery cannulation

Limb ischaemia is a clinically relevant complication of venoarterial extracorporeal membrane oxygenation (VA ECMO) with femoral artery cannulation. No selective distal perfusion or other advanced techniques were used in the past to maintain adequate distal limb perfusion. A more recent trend is the shift from the reactive or emergency management to the pro-active or prophylactic placement of a distal perfusion cannula to avoid or reduce limb ischaemia-related complications. Multiple alternative cannulation techniques to the distal perfusion cannula have been developed to maintain distal limb perfusion, including end-to-side grafting, external or endovascular femoro-femoral bypass, retrograde limb perfusion (e.g., via the posterior tibial, dorsalis pedis or anterior tibial artery), and, more recently, use of a bidirectional cannula. Venous congestion has also been recognized as a potential contributing factor to limb ischaemia development and specific techniques have been described with facilitated venous drainage or bilateral cannulation being the most recent, to reduce or avoid venous stasis as a contributor to impaired limb perfusion. Advances in monitoring techniques, such as near-infrared spectroscopy and duplex ultrasound analysis, have been applied to improve decision-making regarding both the monitoring and management of limb ischaemia. This narrative review describes the evolution of techniques used for distal limb perfusion during peripheral VA ECMO.

Acute Compartment Syndrome in Pediatric Patients on Extracorporeal Membrane Oxygenation Support

BACKGROUND

When acute compartment syndrome (ACS) occurs in pediatric patients requiring venoarterial extracorporeal membrane oxygen (VA ECMO) support, there is little data to guide surgeons on appropriate management. The purpose of this study is to characterize the presentation, diagnosis, timeline, and outcomes of patients who developed this complication.

METHODS

This is a single-center retrospective case series of children below 19 years old on VA ECMO support who subsequently developed extremity ACS between January 2016 and December 2022. Outcomes included fasciotomy findings, amputation, mortality, and documented function at the last follow-up.

RESULTS

Of 343 patients on VA ECMO support, 18 (5.2%) were diagnosed with ACS a median 29 hours after starting ECMO. Initial cannulation sites included 8 femoral, 6 neck, and 4 central. Femoral artery cannulation was associated with an increased risk of ACS [odds ratio=6.0 (CI: 2.2 to 15), P <0.0001]. In the hospital, the mortality rate was 56% (10/18). Fourteen (78%) patients received fasciotomies a median of 1.2 hours after ACS diagnosis. Only 4 (29%) patients had all healthy muscles at initial fasciotomy, while 9 (64%) had poor muscular findings in at least 1 compartment. Patients with worse findings at fasciotomy had a significantly longer duration between ischemia onset and ACS diagnosis. Patients required a median of 1.5 additional procedures after fasciotomy, and only 1 (7%) developed a surgical site infection. Of the 7 surviving fasciotomy patients, 2 required amputations, 3 developed an equinus contracture, 1 developed foot drop, and 3 had no ACS-related deficits. Four patients did not receive fasciotomies: 3 were deemed too ill and later died, and 1 was diagnosed too late to benefit. The only surviving nonfasciotomy patient required bilateral amputations.

CONCLUSIONS

Pediatric ECMO-associated ACS is not exclusive to patients with femoral artery cannulation. The majority of fasciotomy patients were diagnosed with ACS after muscle necrosis had already started. We were unable to definitively conclude whether fasciotomies provide better outcomes. There is a need for increased awareness and earlier recognition of this rare yet potentially devastating complication.

LEVEL OF EVIDENCE

Level IV-retrospective case series.