Perforation During ECMO Cannulation is a known risk that must be mitigated.
A Recent publication in the Journal of Cardiac Surgery from the Children’s Hospital of Philadelphia describes the importance of using echocardiography in placement of the Avalon Elite Bicaval Dual Lumen Cannula in neonates for VV ECMO. The authors share some very important points in their conclusion:
- “Fluid shifts are frequent after initiation of ECMO and are a common cause of systemic hypotension and impaired venous return to the pump, events that typically respond to fluid boluses. Because a slow developing cardiac tamponade causes the same signs and also responds (initially) to fluid boluses, it is somewhat difficult to clinically distinguish between the two at the early stages of development.”
- “As illustrated by our report, the echocardiography at the time of cannulation may fail to detect minor cardiovascular injuries.”
- “Because of this and the known potential risk of cardiovascular perforation, we believe that it is critical to perform routine surveillance echocardiography within the first hours after Avalon Elite cannula placement, and to have a low threshold to repeat the study if the venous return to the pump becomes impaired at any time.”
Cardiovascular Perforation During Placement of an Avalon Elitew Bicaval Dual Lumen ECMO Cannula in a Newborn by Matias E. Czerwonko, M.D., Maria V. Fraga, M.D., David J. Goldberg, M.D., Holly L. Hedrick, and Pablo Laje, M.D Department of Surgery, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA doi: 10.1111/jocs.12507 (J Card Surg 2014;XX:1–3)
Synopisis: The Authors present the case of a 19-day-old term male newborn with profound respiratory failure secondary to adenovirus that met criteria for VV-ECMO. The cannulation was done at the bedside in the Neonatal Intensive Care Unit under direct transthoracic echocardiographic guidance. The right IJV was dissected and the lumen accessed with the 18-gauge needle provided by the manufacturer. The 0.038‘‘ guidewire provided by the manufacturer was threaded toward the IVC under live echocardiographic guidance. The IVC was markedly collapsed. Despite multiple maneuvers, the guidewire could not reach the IVC. We kept the guidewire in the right atrium (RA) and threaded the cannula with the introducer. Once the cannula and introducer reached the RA, the guidewire was retrieved. After multiple maneuvers under direct echocardiography, the tip of the introducer reached the IVC and the cannula was threaded forward. At the end of the procedure the cannula was properly placed, full ECMO flow was achieved without delay, and no recirculation was observed. Over the course of the following hours, the patient’s mean arterial blood pressure gradually decreased. This was attributed to fluid shifts, as it responded to fluid boluses. Venous return to the pump became intermittently impaired. Eight hours postcannulation, the patient went into asystolic arrest. The ECMO circuit was clamped immediately and resuscitation maneuvers initiated. An echocardiogram done within minutes of the arrest showed cardiac tamponade and the heart in asystole. A subxyphoid pericardial window was done; however, the heart remained in asystole. The patient expired 40minutes after the cardiac arrest. The autopsy revealed a pinhole perforation at the posterior aspect of the intrapericardial segment of the IVC. Additionally, the autopsy revealed alveolar hemorrhage and severe acute bronchopneumonia.
The efficacy of a bicaval ECMO cannula is dependent upon precise placement. In newborns, this represents a challenge because minimal cannula movements can result in suboptimal positioning. The use of transthoracic echocardiography is critical at the time of placement to ensure that: (i) the guidewire reaches the IVC; (ii) the distal port of the cannula remains in the lumen of the IVC once the guidewire is retrieved; and (iii) the infusion port is precisely facing the tricuspid valve. Not using any form of imaging guidance is likely to result in malposition of the cannula. Newborns with profound respiratory failure are usually on high-pressure ventilating settings, which can produce overexpansion of the lungs, collapse of the right atrium, mediastinal shift, and distortion of the IVC/RA junction. Placing the guidewire into the IVC can be challenging in newborns, even with the aid of echocardiography.
Figure 1. Echocardiographic view of the right atrium/inferior vena cava at the time of cannula placement. The suprahepatic veins are seen. The interior vena cava is collapsed.
Take home points:
- “Fluid shifts are frequent after initiation of ECMO and are a common cause of systemic hypotension and impaired venous return to the pump, events that typically respond to fluid boluses. Because a slow developing cardiac tamponade causes the same signs and also responds (initially) to fluid boluses, it is somewhat difficult to clinically distinguish between the two at the early stages of development.”
- “As illustrated by our report, the echocardiography at the time of cannulation may fail to detect minor cardiovascular injuries.”
- “Because of this and the known potential risk of cardiovascular perforation, we believe that it is critical to perform routine surveillance echocardiography within the first hours after Avalon Elite1 cannula placement, and to have a low threshold to repeat the study if the venous return to the pump becomes impaired at any time.”
