Clinical Trial Details
— Status: Completed
Administrative data
NCT number |
NCT04587401 |
Other study ID # |
AkdenizU-438 |
Secondary ID |
|
Status |
Completed |
Phase |
N/A
|
First received |
|
Last updated |
|
Start date |
September 1, 2020 |
Est. completion date |
March 2, 2021 |
Study information
Verified date |
September 2020 |
Source |
Akdeniz University |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
High blood pressure is a serious and common health problem. This disease affects 1 billion
people all over the world and responsible for 7,1 million deaths. Trials involving more than
1 million people state that stroke incidence rises as blood pressure rises. The effects of
high blood pressure on cerebral perfusion is not well realized. Intraoperative blood pressure
management of patients with high blood pressure is not well known. And it is still not clear
how autoregulation of cerebral perfusion is affected by high blood pressure.
Systemic arterial pressure changes have little effect on cerebral perfusion. This is
regulated by changes of precapillary resistance. When systemic arterial blood pressure drops,
it is regulated by vasodilatation of arteriolar smooth muscles. And when systemic blood
pressure rises, it is regulated by vasoconstriction of arterioles. Cerebral perfusion is well
preserved between 50-125 mmHg changes of mean arterial blood pressure (MAP). Patients with
high blood pressure have higher ranges. Patients with chronic high blood pressure can better
tolerate higher blood pressures. But even physiologic drops of systemic blood pressure can
cause ischemia.
Anesthetic drugs have variable effects on cerebral blood flow and physiology. The drugs used
with anesthetic drugs, the noxious stimulus of surgery, intracranial compliance, blood
pressure, and carbon dioxide pressure can all alter and complicate these effects. Anesthetic
drugs must be selected carefully in patients with high blood pressure. It is still
investigated whether, management of blood pressure under anesthesia, should be
individualized.
For patients with high blood pressure, some neuromonitorization technics have been evaluated
to prevent neurologic complications under anesthesia. But there is not a technic, which is
considered as a gold standard. Cerebral blood pressure has been studied by, nitrous oxide
method, krypton uptake method, and xenon injection methods previously. Near-infrared
spectroscopy (NIRS) is the best monitorization technic of intracranial pressure (ICP),
cerebral blood flow (CBF), and cerebral metabolism. But it can not be applied to all
patients. Recently, it is possible to measure blood flow of cerebrum with transcranial
Doppler ultrasound in anesthesia practice.
In this trial, the investigators aim to evaluate cerebral perfusion of hypertensive patients
with transcranial Doppler during lumbar disc surgery to optimize the blood pressure under
anesthesia.
To best of our knowledge, there is no trial evaluating cerebral perfusion of hypertensive
patients with transcranial Doppler ultrasound.
Description:
In this trial, the investigators aim to evaluate the cerebral perfusion of patients with
transcranial doppler ultrasound (TCD) and near-infrared spectroscopy (NIRS) during lumbar
disc surgery.
The investigators will divide participants into three groups according to their blood
pressure history after preoperative evaluation of the participants.
The investigators will enroll normotensive participants in group 1(control group).
Participants with diagnosis of high blood pressure will be enrolled to group 2. In the third
group, participants who don't have any diagnosis of high blood pressure, but actual blood
pressure is higher than the physiological levels at the preoperative evaluation will be
enrolled to group 3.
First measurements of TCD and NIRS, will be performed at preoperative period. Second
measurements will be obtained after anesthesia induction. Third measurement will be performed
after prone position. Forth measurement will be taken after 1 hour of surgical incision. The
last measurement will be performed at the postoperative period.
During all these measurements, blood gas samples, invasive arterial blood pressures, pulse
variation index (PVI), electrocardiography (ECG), peripheral oxygen saturation (SpO2), peak
pressure of airway and end-tidal carbon dioxide (EtCO2) levels will also be recorded.
All participants will be evaluated for their cognitive functions with mini-mental and
confusion assessment method (cam) tests at the preoperative and postoperative periods.