Haemo-autologous Antegrade Repriming (HAR) as Minimum Impact Perfusion Strategy for Cardiopulmonary Bypass
Condition: Anemia; Cognitive; Disorder, Due to General Medical Condition; Embolism, Air; Transfusion; Cardiac Disease; Extracorporeal Circulation; Complications; Valve Anomalies
MeSH terms: Embolism; Heart Diseases; Embolism, Air; Cognition Disorders
Study type: Interventional

Summary: 
      Haemo-autologous Antegrade Repriming (HAR) is a procedure based in the combination of
      evidence proven measures designed to reduce the haemodilution caused by establishing the
      cardiopulmonary bypass (CPB) during cardiac surgery.

      This clinical trial aims to determinate, in one hand, the benefits related to HAR in terms of
      transfusion, ICU stay, ventilation time, early mortality and complications. In the other hand
      analyzes the gaseous microemboli (GME) load, comparing the oxygenators venting technology´s
      efficiency in treatment and control group, and its relation with patient´s neurocognitive
      status.
    

Detailed description: 
      HAR is a repriming technique based in Retrograde Autologous Priming (RAP), that has been
      implemented by recently recommended measures in terms of reducing blood transfusions.

      The expected clinical benefits are related to hemodilution´s reduction up to only 300ml. The
      extracorporeal circuit has been reduced to 3/8 inch diameter in both lines, reducing the
      surface up to 1000ml of dynamic priming.

      Vacuum assisted venous drainage (VAVD) allows to empty the venous line after priming and
      deairing, facilitating the venous flow for CPB initiation.

      The antegrade repriming eliminates the maximum amount of crystalloid contained in the
      circuit, displacing it to a collector bag, by using autologous blood sequestered from the
      arterial line to the hardshell reservoir.

      HAR reduces the CPB hemodilution related to priming from 1500 to 300 ml preventing the usual
      sudden haemoglobin level reduction occured during every extracorporeal techinque´s
      establishment.

      Our mission is to analyze if HAR can be validated as a safe and effective tool to improve
      clinical outcomes in cardiac surgery procedures under extracorporeal circulation
    

Intervention name(s): HAR
Intervention type(s): Procedure
Intervention description(s): HAR, the 6 steps procedure that results in 300ml of haemodilution. Step 0: Circuit is primed with 1000ml of crystalloid solution. Step 1: Venous line content is drained to the reservoir. Step 2: arterial srystalloid priming is displaced to the reservoir retrogradely by autologous blood. Step 3: Crystalloid priming is discarded to the collector bag. Step 4: An amount of 300ml of arterial blood is sequestered to the reservoir avoiding the mixture. Step 5: The centrifugal pump and the oxygenator are reprimed with autologous blood displacing the priming and GME to the collector bag. Step 6: CPB is initiated with a low haemodilution of 300ml.
Available at: https://zenodo.org/record/4276132#.X7K8AchKgRk
Other intervention name(s): Haematic antegrade repriming; Extracorporeal circuit repriming
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: In a preliminary phase, patients are randomly assigned to 4 branches, regarding to two conditions: oxygenator´s deairing type and HAR exposure. This phase is designed as pilot study with 100 patients in order to determine precisely the sample size needed depending on the observed effects.
If there are no clinical differences between oxygenators behaviour, during the second stage, sample will be only divided in 2 groups due to HAR exposure.
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: Retrograde autologous priming; RAP; HAR; cardiopulmonary bypass; Extracorporeal circulation; Gaseous microemboli; perfusion