A comparison between cardiac output monitoring using (minimally invasive) esophageal Doppler and (noninvasive) thoracic electrical bioimpedance

ISRCTN	ISRCTN43678006
DOI	https://doi.org/10.1186/ISRCTN43678006
Secondary identifying numbers	MEC 09-4-052

Submission date: 20/09/2017
Registration date: 02/10/2017
Last edited: 25/09/2017

Recruitment status: No longer recruiting
Overall study status: Completed
Condition category: Surgery

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Record updated in last year

Plain English summary of protocol

Background and study aims
During major abdominal surgery patients need to be monitored carefully to ensure that tissues have an adequate blood supply (perfusion) and level of oxygen (oxygenation). This requires monitoring of cardiac (heart) output and stroke volume (the volume of blood per beat) to determine the use of fluids and medication to improve blood pressure and flow. During operations the ideal monitor of cardiac output is as minimally invasive as possible. The aim of this study is to investigate a monitor that is non-invasive and compare it to a widely used minimal invasive monitor. The minimal invasive monitor (esophageal Doppler probe) requires an oral or nasal placed catheter (tube), and the non-invasive device (Aesculon) requires only four electrodes placed in the neck and thorax of the patient.

Who can participate?
Patients aged over 18 who are scheduled for elective major abdominal surgery

What does the study involve?
Under anaesthetic, the esophageal Doppler probe and the Aesculon device are placed on the participant. Cardiac output measurements are performed at eight time points: directly after the start of anaesthesia, after skin incision (cutting), during the surgical procedure when the patient is in a stable condition, after skin closure, just before extubation (removal of breathing tube), and 30 and 60 minutes after arrival in the recovery ward.

What are the possible benefits and risks of participating?
There is no interference with standard care and monitoring. The only difference to standard care is the placement of four additional electrodes.

Where is the study run from?
Maastricht University Medical Centre (Netherlands)

When is the study starting and how long is it expected to run for?
January 2009 to January 2010

Who is funding the study?
Maastricht University Medical Centre (Netherlands)

Who is the main contact?
Mr Boris Cox

Contact information

Mr Boris Cox
Scientific

Maastricht Universitair Medisch Centrum
P. Debyelaan 25
PB 5800
Maastricht
6202AZ
Netherlands

ORCID ID	0000-0001-5906-3792

Study information

Study design	Prospective observational study
Primary study design	Observational
Secondary study design	Case-control study
Study setting(s)	Hospital
Study type	Diagnostic
Participant information sheet	Not available in web format, please use contact details to request a participant information sheet
Scientific title	Accuracy, precision and trending ability of electrical cardiometry cardiac output versus esophageal Doppler: a prospective, observational study
Study objectives	The aim of this study is to compare the accuracy, precision and trending ability of cardiac output measurements of a thoracic bioimpedance technique with esophageal Doppler, before, during and after major abdominal surgery.
Ethics approval(s)	Institutional review board of the Maastricht University Medical Center, 20/07/2009, ref: MEC 09-4-052.2
Health condition(s) or problem(s) studied	Measurement of cardiac output with different devices in patients sheduled for major abdominal surgery
Intervention	Participants are randomly sampled from patients undergoing major abdominal surgery. They receive the standard level of care during surgery. After induction of anesthesia, a esophageal Doppler probe and the Aesculon device are placed on the participant. The index test is a thoracic electrical bioimpedance cardiac output monitor (Aesculon, Osypka Medical, Berlin, Germany). The reference test was a esophageal Doppler probe (CardioQTM, Deltex Medical, Chichester, United Kingdom), using the I2C 72-probe for nasal introduction. The only difference to standard care was the placement of four additional electrocardiography electrodes. Two electrodes are placed in the neck and two are placed at the thoracic level. Only data from standard monitoring and bioimpedance were recorded. All measurements are performed at certain time points and there was no interference with standard care and monitoring. There was no need for follow up within this study group. Measurements are performed at eight time points: (T1) directly after induction of anesthesia, (T2) after skin incision, during the surgical procedure when the patient was in a stable condition (T3, T4) were performed at a random moment, (T5) after skin closure, (T6) just before extubation, (T7) 30 minutes and (T8) 60 minutes after arrival on the recovery ward.
Intervention type	Device
Pharmaceutical study type(s)
Phase
Drug / device / biological / vaccine name(s)
Primary outcome measure	1. Accuracy and precision is measured using Bland Altman analysis by comparing results from the esophageal Doppler to the results of the bioimpedance cardiac output monitor at the eight timepoints. The esophageal Doppler is validated against pulmonary artery catheter, the more or less gold standard of cardiac output measurement. So, the Doppler technique represents the gold standard in this study 2. Trending ability of the techniques is evaluated applying four-quadrant plot and polar plot methodology
Secondary outcome measures	Errors in bioimpedance measures are assessed using interruption of the skin's integrity and opening of the abdominal cavity by a surgical incision at the time of surgery
Overall study start date	10/01/2009
Completion date	07/01/2010

Eligibility

Participant type(s)	Patient
Age group	Adult
Lower age limit	18 Years
Sex	Both
Target number of participants	50 participants
Key inclusion criteria	1. Patients scheduled for elective major abdominal surgery 2. > 18 years old 3. Informed consent
Key exclusion criteria	1. Nasal, pharyngeal, laryngeal or esophageal pathologies 2. Beeding disorders 3. Cardiac arrhythmias 4. Age < 18 years 5. No informed consent
Date of first enrolment	25/08/2009
Date of final enrolment	06/01/2010

Locations

Countries of recruitment

Netherlands

Study participating centre

Maastricht University Medical Centre

Department of Anesthesiology and Pain Management
MUMC+
P. Debyelaan 25
Maastricht
6202AZ
Netherlands

Sponsor information

Maastricht Universitair Medisch Centrum
Hospital/treatment centre

p. Debyelaan 25
PB 5800
6202 AZ Maastricht
Maastricht
6202 AZ
Netherlands

Phone	+31 (0)43 3876543
Email	secretariaat.metc@mumc.nl
Website	http://www.mumc.nl
"ROR"	https://ror.org/02d9ce178

Funders

Funder type

Hospital/treatment centre

Maastricht Universitair Medisch Centrum

No information available

Results and Publications

Intention to publish date	01/03/2018
Individual participant data (IPD) Intention to share	Yes
IPD sharing plan summary	Available on request
Publication and dissemination plan	Submission of the paper is scheduled for October 2017 and publication for February/March 2018. Additional documents are available on request.
IPD sharing plan	The datasets generated during and/or analysed during the current study are/will be available upon request from P.B.W. Cox.