The Effect of Different End-tidal Carbon-dioxide Levels on Cerebral CO2 Vasoreactivity and the Stiffness of Systemic Arteries During Propofol Anesthesia
NCT ID: NCT02203097
Last Updated: 2017-03-09
Study Results
The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.
Basic Information
Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.
COMPLETED
PHASE4
25 participants
INTERVENTIONAL
2014-01-31
2016-12-31
Brief Summary
Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.
The purpose of this study is to examine the effect of different carbon-dioxide concentrations on cerebral CO2 sensitivity and the resistance and stiffness of systemic arteries during anesthesia with target-controlled infusion anesthesia using intravenous propofol. Propofol is a widely and commonly used intravenous anaesthetic, that is mainly used for the induction of general anesthesia and the maintenance of total intravenous anaesthesia (TIVA).
Changes in the velocity of cerebral blood flow and arterial stiffness due to the different exhaled carbon-dioxide concentrations will allow us to conclude how propofol affects these parameters during the course of the narcosis.
Instruments:
An ultrasound device called transcranial doppler (TCD) is used to measure the velocity of blood flow within a main artery located inside the skull.
A tonometry device named SphygmoCor is used to assess the pressure wave proceeding in the radial artery, from which the stiffness of the systemic vessels can be concluded.
Measurements:
\- Examinations with the ultrasound and tonometry devices are carried out once before the operation, three times during the intervention, with different exhaled CO2 values and once after the operation is completed.
Hypothesis:
\- Propofol alters cerebral carbon-dioxide sensitivity and the stiffness of systemic arteries during TCI anaesthesia.
Related Clinical Trials
Explore similar clinical trials based on study characteristics and research focus.
The Effect of Blood Pressure on Cerebral Blood Flow During Propofol Anesthesia
NCT03309917
General Anesthesia and Regional Cerebral Oxygenation inSpine Surgery Prone Position
NCT05148637
Changes in Cerebral Oxygenation During Deliberate Hypotensive Anesthesia
NCT00207987
Hemodynamic Changes After Anesthesia With Propofol: Study of Biomarkers
NCT02442232
Hemodynamic Changes and Propofol Pharmacokinetic Variation During Anesthesia Induction and Knee-chest Positioning
NCT03961958
Detailed Description
Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.
\- The study is conducted in four stages: in the first stage, measurements are performed preoperatively in awake patients. Patients are placed in supine position and mean arterial blood pressure (MAP), heart rate, oxygen saturation are measured. The transcranial doppler (TCD) probe is fixed in place by applying a headband to maintain a constant angle of insonation. Mean blood flow velocity (MBFV) and pulsatility index (PI) in the middle cerebral artery (MCA) are obtained. MCA is insonated through the right temporal window by using pulsed 2 megahertz TCD ultrasound probe. Identification of the MCA is confirmed by using standard criteria, at a depth of 45-55 mm. Cerebral CO2 vasoreactivity is calculated as the percentage change in MBFV or PI for mmHg change in end-tidal CO2 (ETCO2).
SphygmoCor is placed on the left radial artery to obtain data about the central aortic blood pressure, augmentation pressure (AP) and augmentation index normalised to a 75 beat per minute heart rate (Alx75). From the derived aortic pulse, calculations can be made, using the area under the systolic and diastolic part of the curve, to determine the heart's ratio of oxygen supply and demand, it is called the subendocardial viability ratio (SEVR).
As part of the premedication each patient receives 100 mg diclofenac per os 30 minutes and 500 ml Lactated-Ringer infusion 60 minutes prior to the operation.
Anesthesia is induced and maintained with target-controlled infusion anesthesia (TCI) using intravenous propofol at 4 mcg/ml constant plasma concentration. Analgesia is provided by using 2 ug/kg sufentanyl bolus dose at the time of induction. Afterwards 0.6 mg/kg rocuronium is given for muscle paralysis and subsequently patients were intubated with a suitable intratracheal tube. After induction of anaesthesia, the patients are placed on a mechanical ventilation system, using a volume-controlled setting with an air and oxygen mixture set to 0.4 fraction of inspired oxygen (FiO2) , the fresh gas flow rate to 2 l/min. .
Differences in the depth of anesthesia could influence cerebral activity, thereby cerebral metabolism and blood flow. Bispectral index is placed onto every patient in order to assure constant depth of anaesthesia during the intervention.
The second series of TCD and SphygmoCor measurements are performed 20 minutes after the respiratory rate is set to maintain end-tidal CO2 at 40 mmHg in order to allow sufficient time for equilibrium to be reached and the effect of drugs used for the induction of anesthesia to be terminated. Subsequently the examinations are repeated twice again at 35 and 30 mmHg ETCO2. The measurements were carried out 5-5 minutes after adjusting the minute ventilation to reach target ETCO2 values.
Statistical methods:
\- Comparisons between the preoperative and three intraoperative stages of the study are made using repeated measures ANOVA with the Bonferroni post hoc correction. The relationship between MBFV, PI and ETCO2 is assessed using linear regression, while the connection between SEVR, pulse and Alx75 is calculated with bivariate correlation.
Conditions
See the medical conditions and disease areas that this research is targeting or investigating.
Study Design
Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.
NA
SINGLE_GROUP
BASIC_SCIENCE
NONE
Study Groups
Review each arm or cohort in the study, along with the interventions and objectives associated with them.
Propofol
Propofol is administered to all patients via target-controlled infusion (TCI) to reach 4 mcg/ml constant plasma concentration according to the Schneider model during the course of the narcosis.
Partial pressure of CO2 at the end of an exhaled breath
Three previously defined EtCO2 levels (partial pressure of CO2 at the end of an exhaled breath) were adjusted during anesthesia.
Propofol
Propofol is administered to all patients via target-controlled infusion (TCI) to reach 4 mcg/ml constant plasma concentration according to the Schneider model during the course of the narcosis.
Interventions
Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.
Partial pressure of CO2 at the end of an exhaled breath
Three previously defined EtCO2 levels (partial pressure of CO2 at the end of an exhaled breath) were adjusted during anesthesia.
Propofol
Propofol is administered to all patients via target-controlled infusion (TCI) to reach 4 mcg/ml constant plasma concentration according to the Schneider model during the course of the narcosis.
Other Intervention Names
Discover alternative or legacy names that may be used to describe the listed interventions across different sources.
Eligibility Criteria
Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.
Inclusion Criteria
* American Society of Anesthesiologists (ASA) physical classification I. or II.
* Patients undergoing elective varicotomy, inguinal hernioplasty or breast surgery in general anesthesia
Exclusion Criteria
* Patients receiving medication that affects the blood vessels (antihypertensive, antidiabetic, antiarrhythmic medications)
18 Years
50 Years
ALL
No
Sponsors
Meet the organizations funding or collaborating on the study and learn about their roles.
University of Debrecen
OTHER
Responsible Party
Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.
Tamas Vegh, MD
assistant lecturer anesthesiologist and intensive care specialist
Principal Investigators
Learn about the lead researchers overseeing the trial and their institutional affiliations.
Csilla Molnár, MD, PhD
Role: PRINCIPAL_INVESTIGATOR
University of Debrecen Medical and Health Science Center Department of Anesthesiology and Intensive Care 4032-Debrecen, Nagyerdei krt 98. Hungary Tel/fax: +36-52-255-347
Locations
Explore where the study is taking place and check the recruitment status at each participating site.
University of Debrecen Medical and Health Science Center Department of Anesthesiology and Intensive Care
Debrecen, , Hungary
Countries
Review the countries where the study has at least one active or historical site.
References
Explore related publications, articles, or registry entries linked to this study.
Fulesdi B, Limburg M, Bereczki D, Kaplar M, Molnar C, Kappelmayer J, Neuwirth G, Csiba L. Cerebrovascular reactivity and reserve capacity in type II diabetes mellitus. J Diabetes Complications. 1999 Jul-Aug;13(4):191-9. doi: 10.1016/s1056-8727(99)00044-6.
McCulloch TJ, Thompson CL, Turner MJ. A randomized crossover comparison of the effects of propofol and sevoflurane on cerebral hemodynamics during carotid endarterectomy. Anesthesiology. 2007 Jan;106(1):56-64. doi: 10.1097/00000542-200701000-00012.
Lan YC, Shen CH, Kang HM, Chong FC. Pulse transit time reveals drug kinetics on vascular changes affected by propofol. Comput Methods Biomech Biomed Engin. 2012;15(9):949-52. doi: 10.1080/10255842.2011.567981. Epub 2011 May 24.
Strebel S, Kaufmann M, Guardiola PM, Schaefer HG. Cerebral vasomotor responsiveness to carbon dioxide is preserved during propofol and midazolam anesthesia in humans. Anesth Analg. 1994 May;78(5):884-8. doi: 10.1213/00000539-199405000-00009.
Holzer A, Winter W, Greher M, Reddy M, Stark J, Donner A, Zimpfer M, Illievich UM. A comparison of propofol and sevoflurane anaesthesia: effects on aortic blood flow velocity and middle cerebral artery blood flow velocity. Anaesthesia. 2003 Mar;58(3):217-22. doi: 10.1046/j.1365-2044.2003.03041.x.
Previgliano IJ. Assessment: transcranial Doppler ultrasonography: report of the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology. Neurology. 2004 Dec 28;63(12):2457-8; author reply 2457-8. No abstract available.
Juhasz M, Pall D, Fulesdi B, Molnar L, Vegh T, Molnar C. The effect of propofol-sufentanil intravenous anesthesia on systemic and cerebral circulation, cerebral autoregulation and CO2 reactivity: a case series. Braz J Anesthesiol. 2021 Sep-Oct;71(5):558-564. doi: 10.1016/j.bjane.2021.04.002. Epub 2021 Apr 23.
Other Identifiers
Review additional registry numbers or institutional identifiers associated with this trial.
2345
Identifier Type: OTHER
Identifier Source: secondary_id
030167-006/2014/OTIG
Identifier Type: -
Identifier Source: org_study_id
More Related Trials
Additional clinical trials that may be relevant based on similarity analysis.