Cerebral Perfusion Monitoring With Transpharyngeal Ultrasonography (TP-Echo)

This study is currently recruiting participants. (see Contacts and Locations)
Verified April 2014 by University Hospital Inselspital, Berne
Sponsor:
Information provided by (Responsible Party):
University Hospital Inselspital, Berne
ClinicalTrials.gov Identifier:
NCT01828411
First received: March 27, 2013
Last updated: April 29, 2014
Last verified: April 2014
  Purpose

This prospective observational pilot study investigates transpharyngeal ultrasonography (TPU) as an additional neuromonitoring strategy to assess cerebral perfusion during on-pump cardiovascular surgery.

In the first part of the study the investigators will investigate the feasibility of TPU for visualization of aortic arch branches including the innominate and the carotid arteries in twenty patients undergoing coronary artery bypass grafting with extracorporeal circulation (cohort 1.). In the second part the investigators plan to adopt the investigators previous experiences on TPU to a selected population of twelve patients undergoing ascending aortic and/or arch repair in deep hypothermic circulatory arrest (DHCA, cohort 2.). In contrast to cohort 1., patients in cohort 2. are exposed intraoperatively to intermittent cerebral perfusion stops or reductions due to surgical procedure, perfusion technique and their underlying disease (aortic dissection or aortic aneurysm).

The investigators hypothesize that cerebral perfusion monitoring using TPU as a non-invasive technique provides a simple and real-time adjunct to assess blood flow velocity in the extracranial cephalic vessels with Doppler ultrasound. Especially in aortic arch surgery with its inherent risk of cerebral hypoperfusion TPU might be a valuable adjunct to routine.


Condition Intervention
Cardiopulmonary Bypass
Device: Transpharyngeal ultrasonography
Device: Duplex sonography and Transcranial Doppler Ultrasonography

Study Type: Observational
Study Design: Observational Model: Case-Only
Time Perspective: Cross-Sectional
Official Title: Monitoring the Brain in On-pump Cardiovascular Surgery: The Role of Transpharyngeal Ultrasonography as a Non-invasive Adjunct to Assess Cerebral Perfusion

Resource links provided by NLM:


Further study details as provided by University Hospital Inselspital, Berne:

Primary Outcome Measures:
  • accuracy of cerebral flow velocity measurement [ Time Frame: intraoperative phase, expected to be ca. 4 hours ] [ Designated as safety issue: No ]
    Cerebral blood flow velocity measurements will be performed using the pulsed wave Doppler technique. Doppler peak flow velocities (obtained at the same intraoperative phase and at the same time) will be compared between the different Doppler techniques.


Secondary Outcome Measures:
  • clinical feasibility [ Time Frame: intraoperative phase, expected to be ca. 4 hours ] [ Designated as safety issue: No ]
    Clinical feasibility will be assessed by analyzing the accuracy of data concordance, i.e. location of cerebral blood vessel, blood flow velocity and cerebral vessel area between the different Doppler techniques. Data will be plotted using Bland-Altman analysis.


Estimated Enrollment: 32
Study Start Date: April 2013
Estimated Study Completion Date: December 2014
Estimated Primary Completion Date: November 2014 (Final data collection date for primary outcome measure)
Groups/Cohorts Assigned Interventions
Coronary artery bypass group (CABG)
Patients with coronary heart disease requiring coronary artery bypass grafting on cardiopulmonary bypass.
Device: Transpharyngeal ultrasonography
Transpharyngeal Dopplerultrasonography (Device: iE33 xMatrix Philips). Assessment of cerebral blood flow by detection of blood flow velocities in the extracranial carotid arteries during coronary artery bypass grafting.
Device: Duplex sonography and Transcranial Doppler Ultrasonography
Assessment of cerebral blood flow by detection of blood flow velocities in the extracranial carotid and middle cerebral arteries during coronary artery bypass grafting.
Thoracic aortic disease group (TAD)
Patients with thoracic aortic disease (ascending aortic dissection or aneurysm) requiring replacement of the ascending aorta on cardiopulmonary bypass with use of hypothermic circulatory arrest and antegrade cerebral perfusion.
Device: Transpharyngeal ultrasonography
Transpharyngeal Dopplerultrasonography (Device: iE33 xMatrix Philips). Assessment of cerebral blood flow by detection of blood flow velocities in the extracranial carotid arteries during coronary artery bypass grafting.
Device: Duplex sonography and Transcranial Doppler Ultrasonography
Assessment of cerebral blood flow by detection of blood flow velocities in the extracranial carotid and middle cerebral arteries during coronary artery bypass grafting.

Detailed Description:

Background

Cerebral hypo- or malperfusion during cardiovascular surgery can lead to grave consequences including transient cerebral ischemia or stroke impairing patient`s daily life and affect surgical outcome. For this reason a multimodal neuromonitoring strategy using a variety of devices (evoked potentials, near-infrared spectroscopy, transcranial Doppler ultrasonography) with different technologies has been recommended by medical societies. These techniques have various limitations and cannot be used in all clinical situations. In contrast, transpharyngeal ultrasonography (TPU) represents a simple and readily available technique: the transesophageal echocardiography probe, routinely placed in most cardiac surgical patients for monitoring and assessment of surgical results, will be withdrawn into the upper esophagus making the visualization of supraaortic branches possible.

To date, there are several reports about imaging of aortic arch branches using TPU. The utility of this technique, however, for systematic cerebrovascular monitoring has not have been investigated so far.

Objective

The aim of this study is to investigate TPU as a cerebrovascular monitoring adjunct in two cohorts of on-pump cardiac surgery procedures. Clinical feasibility and diagnostic accuracy of antegrade carotid flow detection are compared to the established reference methods of Duplex sonography and transcranial Doppler ultrasound.

Methods

All patients receive anesthetic and surgical management according to institutional standards. Patient enrollment in the study occurs consecutively and unblinded for surgical procedure.

All patients receive TPU, Duplex sonography and transcranial Doppler examination after anesthesia induction preoperatively, during extracorporeal circulation and after weaning from cardiopulmonary bypass. In addition, the patients in cohort 2.(ascending aortic repair with DHCA) receive above mentioned noninvasive ultrasound / Doppler measurements also during the period of DHCA with and without antegrade cerebral perfusion.

Image acquisition and data extraction are conducted by different persons to avoid investigator-related bias.

  Eligibility

Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Sampling Method:   Probability Sample
Study Population

Patients undergoing cardiac surgery at the University Hospital Bern.

Criteria

Inclusion Criteria:

  • Signed informed consent
  • Coronary artery bypass grafting or
  • Replacement of thoracic aorta

Exclusion Criteria

  • Contraindication for transesophageal echocardiography
  • Carotid artery stenosis
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01828411

Contacts
Contact: Gabor Erdoes, MD +41 31 632 2726 Gabor.Erdoes@insel.ch

Locations
Switzerland
Dep. of Anesthesiology and Pain therapy Recruiting
Bern, Switzerland, 3010
Contact: Gabor Erdoes, MD    +41 31 632 2726    Gabor.Erdoes@insel.ch   
Contact: Reto Basciani, MD    +41 31 632 2384    reto.basciani@insel.ch   
Principal Investigator: Gabor Erdoes, MD         
Sponsors and Collaborators
University Hospital Inselspital, Berne
Investigators
Study Chair: Balthasar Eberle, Prof., MD. University Hospital Bern, Dep. of Anesthesiology and Pain therapy
  More Information

Publications:
Responsible Party: University Hospital Inselspital, Berne
ClinicalTrials.gov Identifier: NCT01828411     History of Changes
Other Study ID Numbers: 056/10
Study First Received: March 27, 2013
Last Updated: April 29, 2014
Health Authority: Switzerland: Ethikkommission

Keywords provided by University Hospital Inselspital, Berne:
Cardiac surgery
Echocardiography
Cerebral perfusion
Intraoperative period

ClinicalTrials.gov processed this record on September 16, 2014