Clinical trial NCT03816072: Quantification of Dynamic and Static Cerebral Autoregulation (CA) Under Anaesthesia
Official title: Simultaneous Quantification of Dynamic and Static Cerebral Autoregulation (CA) at Different Steady-state Mean Blood Pressures Under Anaesthesia.
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Cerebrovascular Circulation
Lead sponsor: Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA)
Sponsor class: OTHER
First posted: 2019-01-25
Enrollment: 66
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NON_RANDOMIZED
Intervention model: PARALLEL
Intervention model description: Patients receive either propofol or sevoflurane to maintain anaesthesia. Both treatment groups receive the same phenylephrine and mechanical ventilation regimens.
Primary purpose: BASIC_SCIENCE

Brief summary: Cerebral autoregulation (CA) is the mechanism by which the brain vasculature maintains constancy of cerebral blood flow (CBF). Reliable direct measurements of CBF at different blood pressure levels are difficult because they are invasive and time-consuming. This type of measurement to quantify CA is generally referred to as static cerebral autoregulation (sCA). Alternatively, it is possible to measure CA indirectly from blood pressure oscillations. Dynamic cerebral autoregulation (dCA) measures how quickly the cerebral vessels react to a change in blood pressure to normalize CBF. Since the introduction of transcranial Doppler ultrasound (TCD), it has become possible to estimate CBF velocity relatively easy, which in turn correlates well with CBF changes. This method is widely used to quantify dCA. However, it is not clear how sCA correlates with dCA over a range of physiologic mean blood pressure (MBP). It is important to compare different methods of assessing CA, because impaired CA may result in increased risk of perioperative complications such as stroke. In this study, the investigators were interested in establishing the relationship between sCA and dCA during surgery under general anesthesia. The investigators aim to compare these methods during propofol and sevoflurane anesthesia.


Eligibility criteria: Inclusion Criteria:

* ASA-I or ASA-II, willing and able to give written informed consent, scheduled for elective, non-cardiothoracic surgery under general anaesthesia and age 18 years and above.

Exclusion Criteria:

* Patient related

  * Unable/ unwilling to participate
  * ASA-III or higher
  * Age \< 18 years
  * History of: uncontrolled hypertension, diabetes, Parkinson's disease, uncontrolled cardiac arrhythmia, Pure autonomic failure (formerly called idiopathic orthostatic hypotension), Multiple system atrophy with autonomic failure (formerly called Shy-Drager syndrome), Addison's disease and hypopituitarism, pheochromocytoma, peripheral autonomic neuropathy (e.g., amyloid neuropathy, idiopathic autonomic neuropathy), known cardiomyopathy, extreme left ventricle hypertrophy or ejection fraction \< 30%, proven or suspected allergy for any of the medication used during induction of anaesthesia, malignant hyperthermia.
  * Unability to record transcranial Doppler ultrasound due to anatomical variance (\~5% of population)
  * Contra-indications for intravenous or inhalational anaesthesia.
  * Contra-indications for phenylephrine: severe hypertension, peripheral vascular illness, severe hyperthyroidism
  * Simultaneous use of MAO-inhibitors, dopaminergic or vasoconstrictor ergot alkaloids (bromocriptine, cabergoline, pergolide, ergotamine, methylergometrine, methysergide), linezolid, tricyclic antidepressants, serotonin-norepinephrine reuptake inhibitors, digoxin, quinidine, oxytocin.
* Surgery related

  * Day case surgery
  * Laparoscopy with CO2 insufflation
  * Extreme positioning during surgery (head-down/up tilt, lateral decubitus position, prone)
  * Surgery \< 60 minutes.

Primary outcomes:
measure: Changes in dCA after several MBP-increasing steps.
timeFrame: Intraoperatively
measure: Differences in dCA between sevoflurane and propofol at different steady-state MBP's.
timeFrame: Intraoperatively
Secondary outcomes:
Other outcomes:
Locations:
city: Amsterdam
country: Netherlands
facility: Amsterdam UMC, location AMC
state: Noord-Holland
Study officials:
affiliation: Amsterdam UMC, location AMC
name: Jeroen Hermanides, Dr.
role: PRINCIPAL_INVESTIGATOR
References: