Preoperative Parenteral Thiamine Supplementation in Patients Undergoing Heart Surgery

Study Overview
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Brief Summary
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The objective of this study is to determine whether preoperative parenteral thiamin supplementation does prevent the intra and early postoperative increase of lactate and whether this effect is related to the extent of thiamine deficiency in patients undergoing heart surgery. In addition the prevalence of major thiamin deficiency in patient undergoing heart surgery will be determined.

Detailed Description
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Thiamine (vitamin B1) is a water-soluble vitamin and is involved in several stages of intermediate metabolism which are important for producing energy. Severe thiamin deficiency has been associated with severe lactic acidosis and clinical symptoms of life threatening heart failure. To date, no study has evaluated thiamine levels in patients undergoing heart surgery and the prevalence of thiamine deficiency is not known. Furthermore it is unknown whether moderately reduced thiamin levels are associated with mild forms of perioperative cardiac failure necessitating prolonged inotropic support. In this prospective double blind randomised controlled trial of the effect of a parenteral infusion of thiamin before induction of anaesthesia we will investigate the effect on perioperative lactate increase as primary outcome and extent and duration of inotropic support after cardiac surgery. In addition the pharmacokinetics of a intravenous infusion of 300 mg of thiamin on erythrocyte thiamin content and the amount of thiamine excreted in the 24 hours via the urine will be determined. Baseline thiamin levels in erythrocytes before surgery, as well as nutrition history and body composition will be evaluated as effect modifier.

Official Title
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Preoperative Parenteral Thiamine Supplementation in Patients Undergoing Heart Surgery - a Pilot Study

Conditions
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Heart Failure, Acidosis, Lactic, Thiamine Deficiency

Intervention / Treatment
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* Drug: Vitamin B1-ratiopharm
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age 18 - 100 years planned heart surgery signed informed consent Exclusion Criteria: pregnancy and lactation known allergic reaction to the drugs used mental condition rendering the patient unable to give informed consent inability or contraindications to perform study procedures

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: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Supplementation<br>6 ml Vitamin-B1-ratiopharm in 100 ml normal saline, intravenous, preoperative | Drug: Vitamin B1-ratiopharm<br>* 300 mg Thiaminchloridhydrochlorid, once, intravenous, preoperative<br>* Other names: Vitamin B1-ratiopharm®;|
| Placebo Comparator: Placebo<br>100 ml normal saline, intravenous, preoperative | Drug: Placebo<br>* 100 ml normal saline, intravenous, preoperative<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Thiamine status and lactate levels | Thiamine status: functional parameter - erythrocyte transketolase (α-ETK) expressed as TPP (thiamine pyrophosphate); quantity of vitamin B1 in urine and blood concentrations Lactate levels: lactate levels will be determined by blood gas analysis (BGA) within the routine check. | perioperative | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Prevalence of thiamine deficiency, identification of body composition and length of hospital and ICU stay | Thiamine status: functional parameter - erythrocyte transketolase (α-ETK) expressed as TPP (thiamine pyrophosphate); Body composition: measuring with bioelectrical impedance analysis (BIA) Length of ICU and hospital stay; | 2-3 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Thiamine, Vitamin B1, Thiamine Deficiency, Thiamine supplementation, Cardiac surgery, Lactic Acid