Retrograde Inferior Vena caval Perfusion for Total Aortic arch Replacement Surgery (RIVP-TARS): study protocol for a multicenter, randomized controlled trial

Abstract

Background During total aortic arch replacement surgery (TARS) for patients with acute type A aortic dissection, the organs in the lower body, such as the viscera and spinal cord, are at risk of ischemia even when antegrade cerebral perfusion (ACP) is performed. Combining ACP with retrograde inferior vena caval perfusion (RIVP) during TARS may improve outcomes by providing the lower body with oxygenated blood. Methods This study is designed as a multicenter, computer-generated, randomized controlled, assessor-blind, parallel-group study with a superiority framework in patients scheduled for TARS. A total of 636 patients will be randomized on a 1:1 basis to a moderate hypothermia circulatory arrest (MHCA) group, which will receive selective ACP with moderate hypothermia during TARS; or to an RIVP group, which will receive the combination of RIVP and selective ACP under moderate hypothermia during TARS. The primary outcome will be a composite of early mortality and major complications, including paraplegia, postoperative renal failure, severe liver dysfunction, and gastrointestinal complications. All patients will be analyzed according to the intention-to-treat protocol. Discussion This study aims to assess whether RIVP combined with ACP leads to superior outcomes than ACP alone for patients undergoing TARS under moderate hypothermia. This study seeks to provide high-quality evidence for RIVP to be used in patients with acute type A aortic dissection undergoing TARS. Trial registration Clinicaltrials.gov, ID: NCT03607786 . Registered on 30 July 2018. Electronic supplementary material The online version of this article (10.1186/s13063-019-3319-2) contains supplementary material, which is available to authorized users.

Total body retrograde perfusion during hypothermic circulatory arrest is unsafe

“…The combination of ACP and RIVP, in contrast, shows promise as a safe and effective technique during circulatory arrest, which we are investigating in a multicenter randomized controlled trial. 5…”

Cardiopulmonary bypass for total aortic arch replacement surgery: A review of three techniques

“…This has reduced rates of mortality and neurological complications, yet rates of organ dysfunction in the lower body remain high as a result of inadequate perfusion. For example, rates of spinal ischemia or hemiplegic paraplegia range from 4% to 25%, while rates of dialysis range from 6% to 18% ( 17 ). These adverse events likely become more frequent with longer circulatory arrest.…”

“…The second is the combination of DHCA with antegrade cerebral perfusion (ACP) or retrograde cerebral perfusion (RCP), which may provide blood flow to the brain, but which still leaves the lower body at risk of ischemia. The third is the combination of DHCA with total body perfusion, which can be achieved through the arterial or venous systems, or through our recently proposed combination of ACP with retrograde inferior vena caval perfusion (RIVP) ( 16 , 17 ).…”

Perfusion of brain and viscera using modified retrograde cerebral perfusion for aortic arch surgery

“…After the widespread use of anterograde or retrograde cerebral perfusion to protect the brain during aortic arch replacement surgery, researchers have focused on how to minimize ischemic injury to the lower body during the operation. We reported that anterograde cerebral perfusion combined with retrograde inferior vena caval perfusion provides continuous blood ow to the brain, abdominal viscera, and spinal cord during HCA [2][3][4] . However, this technique requires cross-clamping three arterial branches of the aortic arch, which is unnecessary during HRS.…”