Continuous Hemofiltration During Cardiopulmonary Bypass and Its Effect on Lactatemia

Study Overview
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Brief Summary
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This study aims to analyze the impact of using polysulfone membranes on continuous ultrafiltration with volume replacement in patients undergoing cardiac surgery. In this type of surgery, techniques such as conventional ultrafiltration (CUF) and modified ultrafiltration (MUF) are known for controlling the patient's fluid balance during the procedure. However, there is no scientific evidence on the benefits of continuous haemofiltration with volume replacement and its effect on lactatemia. Method and design: A single center randomized controlled trial, parallel treatment design with patient-blinded to compare outcomes in terms of the lactate clearance rates (quantity/unit of time) of the assigned therapy groups. Participants will be randomly assigned to receive the type of surgery, in order to ensure an unbiased assessment of treatments, randomisation will be performed in eight blocks of five patients. The study groups will be equivalent in all aspects except the procedures they undergo. Participants will be assigned to the first control group without haemofiltration (CG or 1) or one group with haemofiltration using a Polysulfone filter (PG or 2). Data will be collected by a blinded evaluator.

Detailed Description
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To determine whether continuous ultrafiltration with volume replacement using a polysulfone membrane during Cardiopulmonary Bypass (CPB) in patients undergoing cardiac surgery decreases intraoperative lactatemia.

Official Title
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Using Polysulfone Membranes on Continuous Ultrafiltration With Volume Replacement in Patients Undergoing Cardiac

Conditions
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Cardiovascular Diseases

Intervention / Treatment
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* Procedure: Polysulfone Filter
* Procedure: Procedure/ Surgery: without Polysulfone Filter


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients who signed informed consent Patients not undergoing emergency surgery. Surgical procedures performed under normothermic conditions. Patients with a minimum time of 40 minutes before decannulation (after the end of myocardial reperfusion, unclamping of the aorta and the end of CPB). Exclusion Criteria: Emergency medical condition in which it is not possible to collect study data. Heart condition requiring the use of hypothermia or hyperthermia during CPB. Patients without a minimum time of 40 minutes before decannulation (after the end of myocardial reperfusion, unclamping of the aorta and the end of CPB). Patients who cannot manage their fluid balance on their own through diuresis prior to CPB. Patients who are unable to manage excess volume during the surgical procedure by means of spontaneous or forced diuresis with diuretics (positive cumulative balance despite intravenous bolus of diuretics after 75% of the anticipated duration of CPB according to the course of the surgery).

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: The perfusionist's role is essential during the procedure involving Cardiopulmonary Bypass (CPB). This study purpose to know the impact of using polysulfone membranes on continuous ultrafiltration with volume replacement in patients undergoing cardiac surgery. In this type of surgery, techniques such as conventional ultrafiltration (CUF) and modified ultrafiltration (MUF) are known for controlling the patient's fluid balance and blood lactate levels during the procedure.
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Polysulfone Filter Group<br>The purpose of the research is to determine whether, by controlling the patient's hemodilution level and, therefore, the acute anaemia caused by the Cardiopulmonary Bypass (CPB) priming fluid, continuous conventional ultrafiltration (CUF) can decrease serum lactate levels during normothermic CPB by increasing the haematocrit and, consequently, the supply of oxygen to the tissues, and whether the haemofiltration membrane can remove lactate molecules in situations of hyperlactataemia in CPB. | Procedure: Polysulfone Filter<br>* The intervention for this group consisted using a Polysulfone filter in order to hemofiltration in the procedure involving Cardiopulmonary Bypass (CPB).The perfusionist's role is essential during the procedure, as they control both Cardiac Output (CO) and gas exchange, depending on their action, will affect blood lactate levels.<br>|
| Active Comparator: Control Group<br>The purpose of the research is to determine serum lactate levels during normothermic cardiopulmonary bypass procedure (CPB) without continuous hemofiltration of the patient during the CPB. | Procedure: Procedure/ Surgery: without Polysulfone Filter<br>* In this group, no intervention is performed during the procedure involving Cardiopulmonary Bypass (CPB)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Plasma Lactate Level | The lactate level will be measured before Cardiopulmonary Bypass (CPB) in all patients | Baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Maximum Plasma Lactate Level | The maximum level of intraoperative lactate will be measured in all patients, whether the polysulfone membrane has been used or not during Cardiopulmonary Bypass (CPB) | Every 20 minutes from the start of the Cardiopulmonary Bypass (CPB) | 
| Plasma Lactate Level | The level of lactate level will be measured in all patients, whether the polysulfone membrane has been used or not at the end cardiopulmonary bypass (CPB). | 1 minute after the Cardiopulmonary Bypass (CPB) | 
| Plasma Lactate Level in the effluent | To determine lactate levels in the effluent in all ultrafiltered patients | 1 minute after the Cardiopulmonary Bypass (CPB) | 
| Plasma Lactate Level in intensive care unit (ICU) | Lactate level will be measured 24 hours after surgery in ICU stay | 24 hours after the Cardiopulmonary Bypass (CPB) | 
| Serum potassium Level | Serum potassium level measured in routine analysis blood | Every 20 minutes from the start of the Cardiopulmonary Bypass (CPB) | 
| Evaluation criteria of mortality and risk profiles of population | Mortality predicted and operative risk will be measured by scoring systems European System for Cardiac Operative Risk Evaluation (EuroSCORE I) in cardiac surgery in all patients | 10 minutes before the Cardiopulmonary Bypass (CPB) | 
| Hematocrit | Hematocrit measured in routine analysis blood in all patients | Every 20 minutes from the start of the Cardiopulmonary Bypass (CPB) |