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Hypoxemia During SurgeryNCT04174417

Effect of Hypotensive Anesthesia on Cerebral Perfusion and Blood Antioxidant Levels and HIF 1a

A study testing systolic blood pressure (SBP) and mean blood pressure (MBP) in people with Hypoxemia During Surgery and Hypoxia, Brain, run by Bezmialem Vakif University at 1 site in Turkey (Türkiye).

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
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Trial summary

The aim of this study to evaluate the patients who underwent controlled hypotensive anesthesia under standardized depth of anesthesia; preoperative and postoperative blood HIF 1a, TAS, TOS measurement and cerebral perfusion evaluation with NIRS and to investigate tissue hypoxia secondary to hypotensive anesthesia and… Read more about this study

Who is it for?
Ages 18 to 75 years
Conditions the study is for
Hypoxemia During Surgery, Hypoxia, Brain
What is being tested?
systolic blood pressure (SBP) and mean blood pressure (MBP)
Could I receive a placebo?
No, everyone receives an active treatment
How many people
60 participants
Where
1 siteTurkey (Türkiye)
Study dates
14 Nov 2018to 30 Jun 2019
Phase
Interventional
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 to 75 years
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Who may be able to join

  • 18-75 years old
  • ASA Physical Status Classification System 1-2
  • Undergoing to Elective rhinoplasty or maxillofacial surgery

Who cannot join

  • 1. Those with SVO history 2. Patients with carotid stenosis and cardiac failure 3. Chronic smoking 4. Patients with allergies to drugs to be used 5. Patients without intraoperative hypotension 6. Presence of morbid obesity (BMI> 40 kg / m2) 7. Patients who refused to participate in the study
  • Termination criteria
  • Development of severe hypotension and bradycardia during measurements
  • Development of severe drug allergy during follow-up
  • In the event of any complications related to the surgical procedure

Trial locations and contacts

1 site in 1 country.

Turkey (Türkiye)1 site
  • Bezmialem Vakif University

    Istanbul, Fatih, 34093

Other trials in Turkey (Türkiye)

About this study

The aim of this study to evaluate the patients who underwent controlled hypotensive anesthesia under standardized depth of anesthesia; preoperative and postoperative blood HIF 1a, TAS, TOS measurement and cerebral perfusion evaluation with NIRS and to investigate tissue hypoxia secondary to hypotensive anesthesia and the changes of the mediators at the tissue level and which blood pressure parameters are related.

Read the detailed description

Controlled hypotension is the voluntary reversible reduction of arterial blood pressure. Hypotensive anesthesia is a method of anesthesia in which blood pressure is reduced in a controlled manner, especially in certain surgeries. İt reduces intraoperative bleeding and need for blood transfusion and provides a clean surgical vision in narrow-field surgeries or with high bleeding potential. Hypotensive anesthesia can be performed according to mean blood pressure (MBP) or systolic blood pressure (SBP).

A non-invasive cerebral oximeter is used to see the changes in the brain due to high oxygen-dependent metabolism during induction and maintenance of anesthesia.

Hypoxia inducible factor (HIF) is a transcription factor involved in cell adaptation mechanism activated in response to hypoxia.

The biological activity of HIF 1 is determined by the expression and activity of the HIF 1a subunit.

Total antioxidant status (TAS) shows the total effect of all antioxidants in the human body and total oxidant status (TOS) shows the total effect of oxidants.

Near Infrared Spectroscopy (NIRS) allows continuous and non-invasive monitoring of cerebral oxygenation. HIF 1a, TAS and TOS are laboratory markers that predict tissue oxygenation and perfusion.

Hypotensive anesthesia can be performed according to both MBP and SBP. However, in our study that follow-up MBP is more advantageous/protective, although it is not supported by very strong data. The investigators recommend hypotensive anesthesia compared to MBP; but further studies are needed.

Being tested
systolic blood pressure (SBP), mean blood pressure (MBP)
Keywords
hypotensive anesthesia, HIF 1a, Brain Hypoxia, tissue hypoxia
Medical subject headings
Hypoxia, Brain

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • systolic blood pressure (SBP)Procedure or surgery

    Systolic blood pressure (SBP) 80-90 mmHg remifentanil infusion was applied to Group 1 patients. In addition to remifentanil infusion, 0.002 μg.kg of glycerol trinitrate (Perlinganit) was administered as an intermittent bolus in patients who needed to achieve target blood pressure. All patients received 5-8 ml / kg / h IV infusion of balanced electrolyte solution (Isolyte-S) during the operation.

    Hemodynamic parameters (HR, SBP, OCD), BIS, SpO2 and NIRS were recorded at 5 minute intervals. At the end of the operation, 3 ml of blood was taken from the untreated arm of all patients to the HIF1a, TAS and TOS values and sent to the biochemistry laboratory

  • mean blood pressure (MBP)Procedure or surgery

    For group 2, remifentanil infusion was performed with a mean blood pressure (OCD) of 50-65 mmHg. In addition to remifentanil infusion, 0.002 μg.kg of glycerol trinitrate (Perlinganit) was administered as an intermittent bolus in patients who needed to achieve target blood pressure. All patients received 5-8 ml / kg / h IV infusion of balanced electrolyte solution (Isolyte-S) during the operation.

    Hemodynamic parameters (HR, SBP, OCD), BIS, SpO2 and NIRS were recorded at 5 minute intervals. At the end of the operation, 3 ml of blood was taken from the untreated arm of all patients to the HIF1a, TAS and TOS values and sent to the biochemistry laboratory.

Study groups in NCT04174417
Study groupRoleWhat they receive
systolic blood pressure (SBP)Active comparatorSystolic blood pressure (SBP) for group 1 patients 80-90 mmHg
Receives: Procedure: systolic blood pressure (SBP)
mean blood pressure (MBP)Active comparatorMean blood pressure (MBP) for group 2 patients 50-65 mmHg
Receives: Procedure: mean blood pressure (MBP)

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Evaluation of the relationship between hypotensive anesthesia technique and brain hypoxia by the rate of NIRS

    The investigators used to detect brain hypoxia with Near Infrared Spectroscopy (NIRS) (INVOS 5100 Medtronic).

    Near Infrared measurement, primary absorbing molecules in tissue are metal complex chromophores such as hemoglobin, bilirubin and cytochrome.

    The absorption spectra of deoxyhemoglobin (Hb) range between 650-1000 nm, the oxyhemoglobin (Hb02) absorption spectra range between 700-1150 and the cytochrome oxidase aa3 (Caa3) absorption spectra range from 820-840 nm.

    NIRS measures the ratio of oxyhemoglobin to total hemoglobin at a depth of 2.5-3 cm in the area under the sensor.This ratio represents regional cerebral oxygen (RsO2) saturation.

    RSO2 below 40% or more than 25% decrease in baseline is associated with neurological dysfunction and side effects. A 15-20% reduction or less than 50% of the baseline is considered a critical threshold and requires action.

    Measured: intraoperative 2 hours

  2. Evaluation of the relationship between hypotensive anesthesia technique and tissue hypoxia by HIF1a

    Under normoxic conditions, HIF 1a protein can hardly be detected, but when hypoxia starts, its expression starts within 2 minutes and peaks at 4-8 hours of hypoxia.

    3 ml blood was taken into MiniCollect® tubes from the venous cannula placed before anesthesia induction for measure HIF 1a,TAS and TOS. At the end of the operation, 3 ml of blood was taken again from the untreated arm of all patients to the HIF1a, TAS and TOS values and sent to the biochemistry laboratory. The collected blood was centrifuged at 2000 x g for 10 minutes and the separated sera were sent to the biochemical laboratory to be stored at -80 ° C until the study was performed.

    Measured: Change from Baseline HIF 1a at 2 hours

  3. Evaluation of the relationship between hypotensive anesthesia technique and tissue hypoxia by the concentration of TAS

    Plasma TAS and TOS levels are measured with a commercial kit developed by Erel. Values for plasma TAS are expressed in millimeters by the Trolox value per liter.

    3 ml blood was taken into MiniCollect® tubes from the venous cannula placed before anesthesia induction for measure HIF 1a,TAS and TOS. At the end of the operation, 3 ml of blood was taken again from the untreated arm of all patients to the HIF1a, TAS and TOS values and sent to the biochemistry laboratory. The collected blood was centrifuged at 2000 x g for 10 minutes and the separated sera were sent to the biochemical laboratory to be stored at -80 ° C until the study was performed.

    Measured: Change from Baseline TAS levels at 2 hours

  4. Evaluation of the relationship between hypotensive anesthesia technique and tissue hypoxia by the concentration of TOS

    Measurement for TOS is calibrated with hydrogen peroxide and the results are expressed in micromolar by the hydrogen peroxide value per liter (mmol H2O2 equiv / L).

    3 ml blood was taken into MiniCollect® tubes from the venous cannula placed before anesthesia induction for measure HIF 1a,TAS and TOS. At the end of the operation, 3 ml of blood was taken again from the untreated arm of all patients to the HIF1a, TAS and TOS values and sent to the biochemistry laboratory. The collected blood was centrifuged at 2000 x g for 10 minutes and the separated sera were sent to the biochemical laboratory to be stored at -80 ° C until the study was performed.

    Measured: Change from Baseline TOS levels at 2 hours

Secondary outcomes (3)
  1. surgical satisfaction

    At the end of the surgery surgeons evaluated surgical satisfaction. the investigators used surgeon satisfaction score which one is performing like that 1- bad 2-moderate 3-good 4-excellent

    Measured: postoperative 1 minute

  2. bleeding scores

    At the end of the surgery surgeons evaluated bleeding scores. the investigators used bleeding score which one is performing like that 0-No bleeding 1-minor bleeding no aspiration required 2- Minor bleeding, aspiration required 3-minor bleeding, frequent aspiration required, 4-Moderate bleeding, visible only with aspiration 5- Severe bleeding, frequent aspiration required and very hard to perform surgery

    Measured: postoperative 1 minute

  3. anesthetic consumption

    Standard anesthesia induction and propofol and remifentanil infusion were applied to all patients with TIVA technique.

    Measured: postoperative 1 minute

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted22 Nov 2019
  2. Study start14 Nov 2018
  3. Primary completion15 May 2019
  4. Study completion30 Jun 2019

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Screening
Allocation
Randomised
Intervention model
Parallel groups
Model description
A total of 60 ASA 1-2 patients aged between 18-75 who underwent elective rhinoplasty and orthognathic surgery were included the study.The patients were divided into two groups. One group received hypotensive anesthesia according to MBP an done group received SBP. Continuous regional cerebral oxygen saturation was monitored by NIRS in both groups. Blood samples were taken from all patients before anesthesia induction and at the and of the operation and stored for TAS, TOS, HIF 1a. At the and of the operation patients were fallowed in the post anesthesia care unit for 30 minutes and pain and nause vomiting scores were evaluated. İn addition, surgical satisfaction and bleeding scores and anesthetic consumption of both groups were recorded
Masking
Single blind
Who is masked
Participant
Enrolment
60 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT04174417
Sponsor's protocol ID
Ayse01
Status last verified
Dec 2019
First submitted
12 Nov 2019
Last updated
3 Dec 2019
Results posted
No
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
No

Questions about this trial

What is this clinical trial studying?

A study testing systolic blood pressure (SBP) and mean blood pressure (MBP) in people with Hypoxemia During Surgery and Hypoxia, Brain, run by Bezmialem Vakif University at 1 site in Turkey (Türkiye).

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 3 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 3 Dec 2019. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in Turkey (Türkiye). Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Evaluation of the relationship between hypotensive anesthesia technique and brain hypoxia by the rate of NIRS (time frame: intraoperative 2 hours). The study lists 4 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 3 Dec 2019.

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