Veno-Venous Extracorporeal Membrane Oxygenation: Decannulation Technique in the Awake, Spontaneously Breathing Patient
This video describes the authors’ institution’s preferred decannulation technique in the awake, spontaneously breathing patient on veno-venous extracorporeal membrane oxygenation (VV ECMO).
The case involves a twenty-nine-year-old man with a past medical history of congenital diaphragmatic hernia with resultant hypoplastic right lung, pulmonary hypertension (WHO group 2), dextrocardia, and Eisenmenger syndrome with an unrepaired ventricular septal defect. He had been hospitalized for several months while awaiting heart-lung transplantation and ultimately underwent this procedure.
The patient’s immediate postoperative course was complicated by diffuse coagulopathy that required reopening of the chest and primary graft dysfunction requiring VV ECMO cannulation. A 25 French right femoral venous multistage cannula was used, as well as an 18 French right internal jugular return cannula.
He was extubated on ECMO on postoperative day five to facilitate pulmonary rehabilitation. On postoperative day twenty-two, he had successfully passed a twenty-four hour trial off sweep and was decannulated under local anesthesia while breathing spontaneously. Below are the steps of VV ECMO decannulation as described in the video.
Step 1: Betadine prep of femoral venous insertion site.
Step 2: Injection of local anesthetic surrounding insertion site.
Step 3: Repeat prep and local anesthetic injection at internal jugular insertion site.
Step 4: Re-prep entirety of right thigh generously with betadine and drape with sterile towels.
Step 5: Place mattress suture with 0 silk suture in skin surrounding femoral cannula insertion site.
Step 6: Prep and drape right internal jugular insertion site and place mattress suture in skin surrounding insertion site with 0 silk suture.
Step 7: Cut loose all anchoring sutures of femoral cannula.
Step 8: Place ECMO machine in global override, reduce circuit RPMs to zero, and clamp both return and venous tubing.
Step 9: Patient should be sitting upright. Perform a Valsalva maneuver by holding breath while assistant pulls femoral venous cannula and surgeon ties down mattress suture. Pressure is not necessary in the absence of hematoma because of the risk of stasis and thrombosis.
Step 10: With the femoral cannula out, begin the process of autotransfusion. Unclamp the venous and return tubing and gradually increase RPMs of ECMO circuit. Blood will drain down the venous tubing, which should be clamped before meniscus gets close to the pump.
Step 11: Open a bag of crystalloid solution into the circuit and chase remaining blood into the patient via return cannula until the solution is clear while also monitoring hemodynamics to ensure that the patient’s heart is not overfilled.
Step 12: Clamp the return cannula.
Step 13: Cut loose the right internal jugular anchoring sutures.
Step 14: The patient should perform a Valsalva maneuver while the assistant pulls the internal jugular cannula and the surgeon ties a mattress suture.
Conclusions
One takeaway of this technique is that holding pressure at the cannula sites is unnecessary. Furthermore, autotransfusion reduces the patient’s donor exposure by salvaging blood in the circuit. Lastly, patient Valsalva during cannula removal, close monitoring of the venous and return tubing, and use of crystalloid solution to chase autotransfusion are critical in preventing air embolus.
This patient was ultimately discharged on postoperative day seventy-two and hospital day 248 and has been doing well with rehabilitation two months after discharge.
Reference(s)
1. Tonna JE, Abrams D, Brodie D, Greenwood JC, Rubio Mateo-Sidron JA, Usman A, Fan E. Management of Adult Patients Supported with Venovenous Extracorporeal Membrane Oxygenation (VV ECMO): Guideline from the Extracorporeal Life Support Organization (ELSO). ASAIO J. 2021 Jun 1;67(6):601-610. doi: 10.1097/MAT.0000000000001432. PMID: 33965970; PMCID: PMC8315725.