Changes in Plasma Osmolality Related to the Use of Cardiopulmonary Bypass With Hyperosmolar Prime.

Study Overview
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Brief Summary
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During the use of Cardiopulmonary Bypass (CPB) for cardiac surgery there is an instant mixture of the patient's blood and the fluid needed to fill the extracorporeal circuit before use. This will change the composition of the body fluids. This study aims to plot these changes in regard to particle concentration (osmolality).

Detailed Description
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During the use of CPB for cardiac surgery there is an instant mixture of the patient's blood and the fluid needed to prime the extracorporeal circuit. Many studies have pointed to the benefits of using a hyperosmolar prime to counteract formation of tissue oedema. Rapid changes in osmolality may as a serious consequence lead to osmotic demyelination syndrome. At the Heart Centre of Umeå University Hospital, Sweden, there is a tradition of using a hyperosmolar prime. This study aims to explore changes in osmolality during coronary artery bypass grafting surgery by repeated measurements of osmolality and concentration shifts of sodium, glucose and urea in plasma.

Official Title
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Changes in Plasma Osmolality Related to the Use of Cardiopulmonary Bypass With Hyperosmolar Prime, an Observational Study.

Conditions
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Cardiopulmonary Bypass

Intervention / Treatment
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* Other: Blood sampling


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 60-80 yr New York Heart Association Functional Classification(NYHA) I-III Body Surface Area(BSA) 1.8-2.5 m2 Exclusion Criteria: Diabetes Estimated Glomerular Filtration Rate(eGFR)<50ml/min/1,73 m2

Ages Eligible for Study
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Minimum Age: 60 Years
Maximum Age: 80 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| CABG with the aid of CPB.<br>Cardiac surgical patients subjected to coronary artery bypass grafting with the aid of Cardiopulmonary Bypass. Perioperative measurements of osmolality in plasma. | Other: Blood sampling<br>* To explore changes in osmolality during coronary artery bypass grafting surgery with the aid of Cardiopulmonary Bypass by repeated measurements of osmolality and concentration shifts of sodium, glucose and urea in plasma.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in plasma osmolality | Repeated measurements of plasma osmolality aim to outline changes in plasma osmolality related to the use of hyperosmolar prime. | Before surgery; repeated during surgery and on postoperative day 1 and 2. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in osmolar gap | Analysing urea, sodium and glucose in plasma using the same sampling intervals as for plasma osmolality enables calculation of the osmolar gap and to set its relation to the use of hyperosmolar prime | Before surgery; repeated during surgery and on postoperative day 1 and 2. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Osmolality, Sodium, CABG, Cardiovascular Diseases, Cardiopulmonary bypass