Autonomic Cardiovascular Control in Response to Blood Volume Reduction in Blood Donors

Study Overview
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Brief Summary
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The function of the autonomic nervous system can be assessed using baroreflex sensitivity (BRS) and heart rate variability (HRV). Decreased HRV has been shown to be predictive of morbidity and mortality in diverse medical conditions such as acute myocardial infarction, aneurysmal subarachnoid haemorrhage, autoimmune diseases, sepsis and surgery. The function of the autonomic nervous system has not yet been investigated in a pure hypovolemia model. The aim of the current study is therefore to investigate and describe the function of the autonomic nervous system prior to, during and after reduction of blood volume in healthy blood donors.

Official Title
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Autonomic Cardiovascular Control in Response to Blood Volume Reduction in Blood Donors

Conditions
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Autonomic Dysfunction, Autonomic Imbalance, Blood Loss

Intervention / Treatment
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* Device: Monitoring of the autonomic nervous system


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Volonteers eligable for blood donation following the Danish legislation Male Age 30-45 Written informed consent Speak and understand Danish Exclusion Criteria: Volonteers not eligable for blood donation following the Danish legislation, among others due to: Alcohol and drug abuse Cognitive dysfunction Use of anxiolytic or antipsychotic drugs Arrhythmias or heart failure Diabetes mellitus type I Diabetes mellitus type II Use of opioids History of following diseases in the autonomic nervous system: Parkinson disease, multiple sclerosis, autonomic neuropathies History of cerebral apoplexy or transitory cerebral ischemia Dementia American Society of Anesthesiologists (ASA) score ≥ 4 Furthermore: History of orthostatic intolerance and/or orthostatic hypotension Use of following vasodilator antihypertensive drugs: beta-blockers, angiotensin converting enzyme inhibitors (ACEI), angiotensin 2 receptor blockers (ARBs), calcium channel blockers Use of loop diuretics, thiazid diuretics and potassium-sparing diuretics

Ages Eligible for Study
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Minimum Age: 30 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Blood donors<br>Healhy young male bloddonors, aged 30-45 | Device: Monitoring of the autonomic nervous system<br>* Monitoring of the autonomic nervous system using E-patch, LiDCO and Root-Massimo.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in root mean square of successive NN-interval differences (RMSSD) during mobilisation | Measured in ms | 15 minutes prior to and 15 minutes after blood donation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in root mean square of successive NN-interval differences (RMSSD) during sleep | Measured in ms | The night before and night after blood donation | 
| Changes in standard deviation of N-N intervals (SDNN) during mobilisation | Measured in ms | 15 minutes prior to and 15 minutes after blood donation | 
| Changes in standard deviation of N-N intervals (SDNN) during sleep | Measured in ms | The night before and night after blood donation | 
| Percentage of successive RR intervals that differ by more than 50 ms (pNN50) during mobilisation | Measured in % | 15 minutes prior to and 15 minutes after blood donation | 
| Percentage of successive RR intervals that differ by more than 50 ms (pNN50) during sleep | Measured in % | The night before and night after blood donation | 
| Changes in low frequency (LF) power during mobilisation | Measured in ms^2 | 15 minutes prior to and 15 minutes after blood donation | 
| Changes in low frequency (LF) power during sleep | Measured in ms^2 | The night before and night after blood donation | 
| Changes high frequency (HF) power during mobilisation | Measured in ms^2 | 15 minutes prior to and 15 minutes after blood donation | 
| Changes high frequency (HF) power during sleep | Measured in ms^2 | The night before and night after blood donation | 
| Changes in ratio of LF-to-HF power during mobilisation | Measured in % | 15 minutes prior to and 15 minutes after blood donation | 
| Changes in ratio of LF-to-HF power during sleep | Measured in % | The night before and night after blood donation | 
| Changes in S (area of the ellipse which represents total HRV) during mobilisation | Measured in ms | 15 minutes prior to and 15 minutes after blood donation | 
| Changes in S (area of the ellipse which represents total HRV) during sleep | Measured in ms | The night before and night after blood donation | 
| Changes in SD1 (Poincaré plot standard deviation perpendicular the line of identity) during mobilisation | Measured in ms | 15 minutes prior to and 15 minutes after blood donation | 
| Changes in SD1 (Poincaré plot standard deviation perpendicular the line of identity) during sleep | Measured in ms | The night before and night after blood donation | 
| Changes in SD2 (Poincaré plot standard deviation along the line of identity) during mobilisation | Measured in ms | 15 minutes prior to and 15 minutes after blood donation | 
| Changes in SD2 (Poincaré plot standard deviation along the line of identity) during sleep | Measured in ms | The night before and night after blood donation | 
| Changes in SD1/SD2 ratio during mobilisation | Measured in ms | 15 minutes prior to and 15 minutes after blood donation | 
| Changes in SD1/SD2 ratio during sleep | Measured in ms | The night before and night after blood donation | 
| Changes in systolic arterial pressure (SAP) during mobilization | Measured in mmHg by non-invasive LiDCO | 15 minutes prior to and 15 minutes after blood donation | 
| Changes in diastolic arterial pressure (DAP) during mobilization | Measured in mmHg by non-invasive LiDCO | 15 minutes prior to and 15 minutes after blood donation | 
| Changes in mean arterial pressure (MAP) during mobilization | Measured in mmHg by non-invasive LiDCO | 15 minutes prior to and 15 minutes after blood donation | 
| Changes in pulse pressure (PP) during mobilization | Measured in mmHg by non-invasive LiDCO | 15 minutes prior to and 15 minutes after blood donation | 
| Changes in heart rate (HR) during mobilisation | Measured in beats min-1 by non-invasive LiDCO | 15 minutes prior to and 15 minutes after blood donation | 
| Changes in cardiac output (CO) during mobilization | Measured in L/min by non-invasive LiDCO | 15 minutes prior to and 15 minutes after blood donation | 
| Changes in stroke volume (SV) during mobilization | Measured in mL by non-invasive LiDCO | 15 minutes prior to and 15 minutes after blood donation | 
| Changes in systemic vascular resistance (SVR) during mobilization | Measured in dynes s cm-5 by non-invasive LiDCO | 15 minutes prior to and 15 minutes after blood donation | 
| Changes in cerebral perfusion (ScO2) during mobilization | Measured in % by Root Masimo | 15 minutes prior to and 15 minutes after blood donation | 
| Changes in muscular perfusion (SmO2) during mobilization | Measured in % by Root Masimo | 15 minutes prior to and 15 minutes after blood donation | 
| Changes in peripheral index during mobilization | Measured in % by Root Masimo | 15 minutes prior to and 15 minutes after blood donation | 
| Concentration of C-reacitve protein | Measured in gr/dL | At time of blood donation | 
| V-PLEX Biomarker 54.Plex Kit | 54 key analytes that are important in inflammation response and immune system regulation as well as numerous other biological processes | Blood taken at time of blood donation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Heart rate variabilty, Baroreceptor sensitivity, Autonomic nervous system, Acute blood loss, Blood donors, Autonomic cardiovascular control