- ICH GCP
- US Clinical Trials Registry
- Clinical Trial NCT03009305
Cerebral Oximetry in Lower Body Negative Pressure
Cerebral Oxygen Saturation, Mean Systemic Filling Pressure and Haemodynamic Effects of PEP and CPAP in Lower Body Negative Pressure
The study aims to describe hemodynamic effects of lower body negative pressure (LBNP).
- If and how changes in cerebral oxygen saturation (StO2) measured by near infrared spectroscopy (NIRS) relate to changes in blood flow in the carotid arteries during progressive LBNP.
- If and how mean systemic filling pressure (MSFP) can be measured by brief occlusion of blood flow to an arm and if this relates to LBNP-level.
- If and how pulse pressure variations and photoplethysmographic amplitude variations during positive expiratory pressure (PEP) and continuous positive airway pressure (CPAP) relate to LBNP-level.
Study Overview
Status
Conditions
Detailed Description
20 healthy volunteers will be included. The study protocol consists of two parts.
LBNP is applied stepwise (20 mmHg increments). At each LBNP-level, after 2 min stabilization, blood flow in internal and external carotid arteries is measured. Thereafter, MSFP is measured. LBNP is applied to -80 mmHg, but terminated sooner if the subject experiences signs of decompensation.
Changes in cerebral StO2 will be related to relative changes in blood flow in the carotid arteries. After these measurements, blood flow to one arm will be occluded for 30 s. Venous pressure measured in an antecubital vein approximates MSFP. This will be related to volume status (LBNP-level and stroke volume reduction).
- LBNP is applied stepwise (20 mmHg increments). At each LBNP-level, after 2 min stabilization, PEP and CPAP are applied at 0, 5 and 10 cmH20. LBNP is applied to -80 mmHg, but terminated sooner if the subject experiences signs of decompensation.
Flow in carotid arteries is measured by ultrasound/Doppler. Skin blood flow in the forehead measured by laser Doppler flowmetry and transcutaneous oxygen saturation.
If possible, blood flow velocity in a. cerebri media will be measured by transcranial Doppler.
Central venous pressure will be approximated by measuring pressure in the left subclavian vein ("half-way" catheter).
Cardiac stroke volume will be measured by suprasternal Doppler. Expiratory carbon dioxide (CO2) will be measured and recorded. Acral skin photoplethysmography performed using proprietary and custom-made photoplethysmographs.
Arterial blood pressure approximated by finger volume-clamp method.
The measurements above will be used for analyses of possible physiological mechanisms and post-hoc analyses.
Study Type
Enrollment (Actual)
Phase
- Not Applicable
Contacts and Locations
Study Locations
-
-
-
Oslo, Norway, 0450
- Oslo University Hospital
-
-
Participation Criteria
Eligibility Criteria
Ages Eligible for Study
Accepts Healthy Volunteers
Genders Eligible for Study
Description
Inclusion Criteria:
- Healthy volunteer (informed consent)
Exclusion Criteria:
- Disease/physical condition limiting normal physical activity or requiring medication (except allergies/contraceptives)
- History of syncope (except with obvious vasovagal etiology)
- Cardiac arrhythmia
- Pregnancy
- Skin infections in the elbow crease
Study Plan
How is the study designed?
Design Details
- Primary Purpose: Diagnostic
- Allocation: N/A
- Interventional Model: Single Group Assignment
- Masking: None (Open Label)
Arms and Interventions
Participant Group / Arm |
Intervention / Treatment |
---|---|
Experimental: Lower body negative pressure
Single-arm, lower body negative pressure, continuous positive airway pressure, positive expiratory pressure.
|
Model of hypovolemia: Lower body negative pressure down to -80 mmHg (maximum).
CPAP of 0, 5 and 10 cm water (H2O).
Other Names:
PEP of 0, 5 and 10 cm H2O.
Other Names:
|
What is the study measuring?
Primary Outcome Measures
Outcome Measure |
Measure Description |
Time Frame |
---|---|---|
StO2 (tissue oxygen saturation).
Time Frame: Approximatrly 30 min: From start LBNP (lower body negative pressure) exposure to 5 min after end LBNP.
|
Association between cerebral StO2 and flow in a. carotis interna.
|
Approximatrly 30 min: From start LBNP (lower body negative pressure) exposure to 5 min after end LBNP.
|
Secondary Outcome Measures
Outcome Measure |
Measure Description |
Time Frame |
---|---|---|
MSFP, mean systemic filling pressure (arm venous pressure during vascular occlusion).
Time Frame: Approximatrly 30 min: From start LBNP (lower body negative pressure) exposure to 5 min after end LBNP.
|
Association between MSFP and volume status.
|
Approximatrly 30 min: From start LBNP (lower body negative pressure) exposure to 5 min after end LBNP.
|
Dynamic variables and PEP (positive expiratory pressure)/CPAP (continuous positive airway pressure)
Time Frame: Approximatrly 30 min: From start LBNP (lower body negative pressure) exposure to 5 min after end LBNP.
|
Association between dynamic variables during PEP/CPAP and volume status.
Dynamic variables (variations in arterial pressure and photoplethysmographic waveforms with respiration) are calculated during with PEP and CPAP during hypovolemia (lower body negative pressure).
|
Approximatrly 30 min: From start LBNP (lower body negative pressure) exposure to 5 min after end LBNP.
|
Collaborators and Investigators
Sponsor
Investigators
- Principal Investigator: Svein Aslak Landsverk, M.D., PhD, Oslo University Hospital
Study record dates
Study Major Dates
Study Start
Primary Completion (Actual)
Study Completion (Actual)
Study Registration Dates
First Submitted
First Submitted That Met QC Criteria
First Posted (Estimate)
Study Record Updates
Last Update Posted (Actual)
Last Update Submitted That Met QC Criteria
Last Verified
More Information
Terms related to this study
Additional Relevant MeSH Terms
Other Study ID Numbers
- 2015/3995
This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.
Clinical Trials on Hypovolemia
-
University of California, DavisCompletedAcute HypovolemiaUnited States
-
B. Braun Melsungen AGCompletedTreatment of Hypovolemia and ShockSpain, Bulgaria, Germany, Italy, United Kingdom
-
Fresenius Kabi JapanCompletedPlasma Volume Substitution (Hypovolemia) Including Massive HemorrhageJapan
-
Karolinska InstitutetDanderyd Hospital; Austin Hospital, Melbourne AustraliaUnknownSepsis | Fluid Therapy | Hypovolemia | Post-operative HypovolemiaAustralia, Sweden
-
Azienda Ospedaliera di PadovaUnknownHypovolemia During Liver Transplantation | Renal Hypoperfusion During Liver TransplantationItaly
-
Fresenius KabiB. Braun Melsungen AG; European Society of Anaesthesiology and Intensive CareCompletedHypovolemia Due to Acute Blood LossGermany, Spain, France, Czechia, South Africa, Belgium, Netherlands
-
Zagazig UniversityNot yet recruitingAnesthesia | Fluid Overload | ERAS | Hypovolemia; Surgical Shock
-
Kedrion S.p.A.inVentiv Health ClinicalTerminated
-
Seoul National University HospitalCompletedHypovolemiaKorea, Republic of
-
B. Braun Medical LLCCompleted
Clinical Trials on Lower body negative pressure
-
University of British ColumbiaRecruitingHeart Failure With Preserved Ejection FractionCanada
-
Yale UniversityRecruitingHypovolemia | Hemodynamic InstabilityUnited States
-
University of Texas Southwestern Medical CenterCompletedSpace Flight Associated Neuro-ocular SyndromeUnited States
-
Mayo ClinicCompletedHypotension and ShockUnited States
-
Milton S. Hershey Medical CenterNational Center for Advancing Translational Sciences (NCATS)Recruiting
-
University Hospital, LinkoepingCompleted
-
Mayo ClinicCompletedHypotension and ShockUnited States
-
University of Illinois at ChicagoEunice Kennedy Shriver National Institute of Child Health and Human Development...Terminated
-
Oslo University HospitalUniversity Hospital, AkershusRecruitingHypovolemia | Hemodynamic Instability | Fluid LossNorway