How the heart-lung machine priming fluid affects blood chemistry during heart surgery

Heart-Lung Machine: Impact of the Priming Solution on the Body's Acid-Base Balance, Electrolyte Composition and Clinical Outcome (PRIMEII)

Not applicable Interventional Region Skane · NCT07267546

This trial will test whether different priming fluids used to fill the heart-lung machine change acid-base balance, electrolytes, and osmolality in adults having isolated CABG or aortic valve replacement.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment80 (estimated)
Ages18 Years and up
SexAll
SponsorRegion Skane Academic / other
Locations1 site (Lund)
Trial IDNCT07267546 on ClinicalTrials.gov

What this trial studies

Adults undergoing isolated coronary artery bypass grafting or aortic valve replacement at a single center will receive one of four cardiopulmonary bypass priming regimens. The CPB circuit is filled with about 1100 mL of fluid before connection, and the trial compares Ringer's acetate (with two different modifications) and Plasma-Lyte as priming solutions. Blood chemistry including acid-base parameters, electrolytes, and plasma osmolality will be sampled around the operative period to track immediate changes. Clinical outcomes and laboratory values will be compared between groups to determine which priming approach best preserves homeostasis.

Who should consider this trial

Good fit: Adults 18 years or older, weighing 60–120 kg, with preserved heart function (EF ≥45%), normal preoperative sodium and hemoglobin ≥120 g/L, and scheduled for isolated CABG or isolated AVR who give informed consent are ideal candidates.

Not a fit: Patients with reduced ejection fraction, severe kidney impairment (GFR <30 ml/min), abnormal sodium, low hemoglobin, very low or high body weight, urgent surgery, or those requiring additional intraoperative procedures are unlikely to benefit or are excluded.

Why it matters

Potential benefit: If successful, the results could guide choice of priming fluid to better preserve electrolyte and acid-base balance and potentially reduce perioperative complications.

How similar studies have performed: Balanced crystalloid versus other fluids for CPB priming and for broader perioperative care has been studied before with mixed results, so this is a focused comparison but not wholly novel.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Patients 18 years and above
* Undergoing coronary artery bypass graft (CABG) surgery as single surgery
* Undergoing aortic valve replacement (AVR) as single surgery (AtriClip is allowed)
* Given consent to participate, both verbal and written

Exclusion Criteria:

* Subnormal heart function (defined as an ejection fraction \<45%), and no signs of heart failure (edema).
* Body weight \<60 kg or \>120 kg
* Preoperative hemoglobin \<120 g/L,
* Subnormal kidney function (defined as GFR \<30 ml/min),
* Blood sodium outside normal range (135-145 mmol/l),
* Need of acute surgery
* AVR due to aortic valve insufficiency
* Changes in operating method or addition of intraoperative procedures.

Where this trial is running

Lund

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Acid Base ImbalanceOsmolality DisturbanceCrystalloid SolutionsElectrolyte ChangesCardiopulmonary Bypasscardiopulmonary bypasspriming solutionacid base balance
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.