Brief Title
Microembolic Signals and Cerebrospinal Fluid Markers of Neuronal Damage After Surgical Aortic Valve Replacement
Official Title
Microembolic Signals and Cerebrospinal Fluid Markers of Neuronal Damage After Surgical Aortic Valve
Brief Summary
The use of MRI have shown that the incidence of postoperative cerebral lesions due to
cerebral embolization is high (1). Nonetheless the extent of postoperative neurological
dysfunction is only a fraction of the actual amount of new postoperative changes detected on
MRI. Transcranial Doppler (TCD) has shown the occurrence of extensive microembolic signals in
intracerebral arteries during open heart procedures (2). The clinical significance of
cerebral microemboli is not clear (3-5). The use of serological markers to assess cerebral
injury after open cardiac surgery is difficult to interpret. The levels of markers seems to
be contaminated from extracerebral sources (6). In order assess the release of markers of
neuronal damage after open aortic valve surgery the investigators intend to examine the
levels of S-100B, NSE and Tau in cerebrospinal fluid (CSF) by comparing the levels
preoperative with the levels one day after surgery. Furthermore the investigators will
determine the total amount of cerebral microembolic signals during the surgical procedure by
means of TCD. The investigators will statistically test if there is any correlation between
the increase in cerebrospinal fluid levels of S-100B,NSE and Tau and the cerebral embolic
load.
Detailed Description
Patients and clinical procedures 10 patients scheduled for open aortic valve surgery at our
institution will be included into this prospective, observational study. The Human Ethics
Committee of the University of Gothenburg, approved the study protocol. The day before
surgery a lumbar puncture at level L3-4 will be performed using a 27G Whitacre needle. A
sample of 2.5 ml of cerebrospinal fluid will be taken for analysis of S-100B, NSE, Tau and
albumin.
On arrival at OR, standard perioperative monitoring will be established, including an
Auditory Evoked Potential (AEP) monitor for anaesthetic depth measurements (AEP Monitor/2,
Danmeter, Odense, Denmark) and radial arterial and central venous lines. General anaesthesia
is induced with propofol 0.5-1 mg/kg and fentanyl 10 μg/kg. Tracheal intubation will be
facilitated using atracurium 0,5 mg/kg. Sevoflurane is used to maintain an anaesthetic depth
adjusted to an AAI index of 15-30 as recorded by the AEP monitor. Hemodynamic stability will
be obtained by the use of colloidal solution administration, guided by the use of
intra-operative transesophageal echocardiography, and norephineprine to maintain a mean
arterial pressure above 75 mmHg-Also during CPB. A lumbar puncture will be repeated the first
postoperative day repeating the measurement of markers in CSF A certified cardiologist or
anaesthesiologist assess focal neurological impairment before and within 24 hours after the
procedure.
Transcranial Doppler (TCD) By TCD the right medial cerebral artery (RMCA) will be insonated
by the transtemporal approach at a depth of approximately 50 mm using standard criteria. The
investigators use a 2 MHz power M-mode TCD monitor (ST3 ©, Spencer Technologies Seattle, WA),
with the probe fixed in position using a head frame. The Doppler signals will be continuously
monitored and saved to monitor hard drive. Two physicians independently evaluate the TCD data
files offline, and identify microembolic signals (MES) using criteria for counting emboli
signals on spectral and PMD TCD.
Statistical Analysis: Descriptive statistics and tests of normality for continuos data
Correlation analysis; Total cerebral embolic load vs. increase of CSF level S-100B/ NSE/Tau.
Study Type
Observational
Primary Outcome
Transcranial Doppler(TCD) Microembolic Signals During Surgical Aortic Valve Replacement Surgery
Secondary Outcome
Cerebrospinal Fluid(CSF) Levels of S-100B(Microgram/Liter)
Condition
Aortic Stenosis
Intervention
Open heart surgery
Study Arms / Comparison Groups
Surgical aortic valve replacement
Description: Single observational study. Count of microembolic signals during open heart surgery and measurement of properative vs postoperative levels of markers in cerebrospinal fluid of neuronal damge.
Publications
* Includes publications given by the data provider as well as publications identified by National Clinical Trials Identifier (NCT ID) in Medline.
Recruitment Information
Recruitment Status
Other
Estimated Enrollment
10
Start Date
November 2010
Completion Date
June 2011
Primary Completion Date
June 2011
Eligibility Criteria
Inclusion Criteria:
- Clinical diagnosis aortic stenosis eligible for surgical treatment
Exclusion Criteria:
- Coagulopathy
- Regular Anticoagulation therapy
- Carotid stenosis
Gender
All
Ages
N/A - N/A
Accepts Healthy Volunteers
No
Contacts
Sven Erik Ricksten, Professor, ,
Location Countries
Sweden
Location Countries
Sweden
Administrative Informations
NCT ID
NCT01319799
Organization ID
Dnr112-09
Responsible Party
Principal Investigator
Study Sponsor
Sahlgrenska University Hospital, Sweden
Study Sponsor
Sven Erik Ricksten, Professor, Study Director, Sahlgrenska University Hospital,Thoracic Anesthesia & Intensive Care
Verification Date
February 2017