You Are Here: Deltex Medical > Education & Training
Education, Training & E-Learning

Education, Training and E-Learning

Deltex Medical has a large body of Clinical Evidence and Educational Resources to support any hospital education program.

As well as  a large number of clinical papers, available in our Library, we have a range of Randomized Controlled Trials and a Meta-Analysis. These will provide an in-depth understanding of how Esophageal Doppler Monitoring, Fluid Management and Enhanced Recovery can improve patient outcomes.

The Decision Tree was developed as an evidence based protocol for use with the ODM+ oesophageal Doppler monitor. It can be used to assess cardiovascular function; guide vasoactive therapy following fluid management and to improve outcomes.  View the Decision Tree flyer.

Our highly qualified Clinical Support Specialists possess a wealth of experience. Their mission is to deliver customized training and educational support programs for the EDM and EDM+ in the ICU and Surgical settings.  This can be incorporated within a systemic and controlled implementation plan.


Training and Support

The Deltex Medical Clinical Team possesses a wealth of experience in hemodynamic optimization and Enhanced Recovery protocols. We are here to help you to get the most out of our powerful system and achieve the outcomes that oesophageal Doppler monitoring using the Deltex EDM+ system has been proven to deliver.

A range of training options is available for the use of EDM+, from initial use of the product to advanced hemodynamic applications.

An excellent starting point is Deltex’s Training Workbook (PDF).

Classroom Sessions

Classroom sessions are available for clinicians who will be users of the EDM or EDM+. The duration and content can be set according to specific needs and may include: cardiac anatomy and physiology, overview of the technology, clinical evidence, the need for fluid management and more.

Hands on support can also be arranged to follow on from classroom sessions or can also be arranged independently.  A dedicated Clinical Support Specialist can arrange to be present for up to 3 months to implement the technology as a standard of care.

Please contact Deltex Medical or your local Clinical Support Specialist  to discuss requirements.


Deltex Medical has developed an an e-Learning package, incorporating EDM+, fluid and cardiac drug management and case studies. Other topics include:

    • cardiac anatomy and physiology in relation to the use of EDM+
    • precision and accuracy
    • arterial compliance
    • unique considerations for the patient in the operating theatre or intensive care
    • importance of individual fluid requirements and management
    • better patient outcomes
    • use of the training simulator
    • pediatric training

Deltex Medical e-Learning provides a platform for accelerated learning, allowing a user to build on existing knowledge, at a time and place that suits. It also provides foundation level training for trainees, ensuring the required knowledge level is achieved to participate in patient management regimes.

Deltex Medical will develop a process for accreditation through various and appropriate accredited certification bodies.

Visit for further information.


The probe is placed into the esophagus, either orally or nasally and is similar to placing a nasogastric tube. The EDM monitor uses Doppler ultrasound technology to determine directly a patient’s central vascular blood flow and fluid status during the intraoperative period.

Easy to use and quick to focus, the device generates a low frequency ultrasound signal which is highly sensitive to changes in flow and measures them immediately.

Once in position the clinician is able to measure real time blood velocities within the descending aorta.

Inserting the Probe Orally

Inserting the Probe Nasally


Focussing the Probe

How to get the optimal focus


  • It is useful to place the probe as early as possible for instance immediately after intubation so that a settling in period can be achieved where the probe sits comfortably against the esophageal wall and the patient’s secretions will aid signal acquisition.
  • Insert the probe to deepest marker of where it was placed, i.e. 3rd marker if placed nasally, 2nd marker if placed orally to start with in an adult.
  • Turn up the sound on the monitor.
  • Choose this depth and rotate slowly all way round without letting go.
  • If no signal is seen at this depth, pull out slightly (by approximately 1 cm at a time) and rotate again slowly without letting go.
  • Repeat these changes of depth followed by rotations until a signal is found.
  • Do not pull and rotate at the same time as this will cause a spiral effect and the appropriate area may be missed.
  • Ensure the edge of the nose or the incisors is as near to the appropriate depth markers. If the patient is very tall or very short, it might be acceptable for the depth markers to be outside of nose or incisors by a small amount.


The qualities of a good signal:


  • The loudest, sharpest ‘whipcrack’ sound
  • The tallest waveform
  • The brightest waveform
  • A well-defined triangle with a black centre surrounded by red with white in the trailing edge. This indicates an equal distribution of red blood cell velocities at a given point in time and the probe is facing the centre of the aorta. If the waveform has no black centre, this is called spectral dispersion and may indicate that the probe is not facing the centre of the aorta.
  • The incisors or edge of nostrils will be as close to the appropriate depth marker as possible.

Find a signal that meets the above requirements and it may be useful to recheck at different depths once more to ensure the optimal signal has not been missed.

Check the gain manually or use autogain. This will help to adjust the signal quality.

When in run mode, check the cycle time. 5 is the default but can be increased for arrhythmias or decreased if there is noise interference.

Ensure the green follower line is set tightly against the waveform and the white arrows are placed on the triangle.


To refocus:


  • Ensure the probe is at the same depth when the optimal signal was found
  • Turn up the volume
  • Rotate slowly without letting go to find the appropriate signal again before evaluating the parameters.


Overview of the Decision Tree


The esophageal Doppler monitor (EDM+),  was developed as a relatively non-invasive, but extremely precise method of measuring cardiac output. Although initially developed as a less invasive alternative to the pulmonary artery catheter, from its early inception it was recognised that the technology is uniquely adept at driving flow based treatment algorithms. Doppler guided fluid management protocols have been proven to improve outcomes in a variety of patient groups.

Doppler guided stroke volume optimization has been proven in several clinical outcome studies to be beneficial to patients. It is also clear that both excessive fluid volumes and inadequate volume are extremely detrimental to patient outcome. The decision tree is a consolidation of this evidence base and the use of vasoactive and inotropic interventions as part of a global hemodynamic protocol.

An expert panel of senior clinicians reviewed the available evidence and agreed on a rational approach to using Doppler flow based measurements to guide therapy. The decision tree considers patients both perioperatively and in critical care.

Using the Decision Tree

Navigation is by a series of Yes/No boxes. Commands are in blue boxes and questions are in gray boxes. Please note that caveats are presented which may lead to an alternative pathway. Caveats are in a red box with red pathways. Caveats should be ignored if inappropriate to the patient.

A good understanding of cardiovascular physiology is important. Ensure optimal focus is obtained before interpretation of data.

Visit the Decision Tree website:

Trigger Points and Concerns

The decision tree was developed to be used in conjunction with flow measurements using the esophageal Doppler monitor.

A good understanding of cardiovascular physiology is essential, including preload, afterload and contractility. Always ensure optimal focus of the Doppler probe is achieved before analyzing the data.

NOTE – These trigger points and concerns:​

        • Should not be assessed in isolation.
        • Are not the same as physiological targets
        • Are indicative and not absolute
        • Are not prioritized

Primary Clinical Indicators

        • Hypotension: e.g. Systolic < 100 mmHg, MAP < 60 -70 mmHg or a clinically significant drop in MAP – e.g. 30 – 40 mmHg from assumed ‘normal’ or baseline
        • Tachycardia: e.g. > 90 bpm
        • Oliguria: < 0.5 ml/kg/h
        • Low Cardiac Output State ​​

Flow Indicators

        •  Reduced FTc: < 330 ms or considered low for clinical condition e.g. any high resistant state
        •  Low Cardiac Output: significantly below ‘normal’ e.g. CO < 4– 6 L, CI < 2.5 L/min/m​²
        •  Low Stroke Volume: significantly below ‘normal’ e.g. SV < 50 – 70 ml, SVI < 30 ml

Supplementary Clinical Indicators

        •  Hypertension: e.g. Systolic > 180 mmHg or > 30 – 40 mmHg above baseline
        •  Lactate: > 2 mmol/L
        •  Base Excess: -3 or +3 mEq/L​
        •  Peripheral Shutdown: – Looks ‘unwell’ e.g. pale, sweaty or a clinical picture of poor perfusion
        •  SaO2: < 93% or having to increase FiO2 by 20% to maintain sats.
        •  ​Low ScVO2: < 65 – 70%
        •  Reduced Consciousness Level: any deterioration rather than a score​


        • Temperature
        •  DO2
        •  CVP
        •  SVR
        •  ​SVV/PPV

For further information please contact us.


How easy is it to use EDM?

The majority of new EDM users find the product easy to handle, place and manipulate the probes. Evidence suggests it takes up to 12 probe insertions to become competent, The manufacturer’s surveillance reports show that in more than 90% of cases, it takes less than two minutes to get a first good signal. In a typical major operation, of 3-4 hours duration, the total time spent interfacing with the monitor and probe is between three and four minutes.

Does EDM lead to excessive or inadequate fluid?

Individualized Doppler guided fluid management tailors the amount of fluid to the individual patient at any given time under various anesthetic or sedation strategies. The goal is to ensure the patient receives the correct volume of intravascular fluids at the correct time.

Is the EDM safe?

EDM has been used in over 400,000 patients worldwide. To date, there have been no serious adverse events associated with EDM. In all, eight potential adverse incidents have been reported, however after investigation none of the eight were attributed to EDM use. The manufacturer’s instructions for use lists the contraindications. In summary, particular care should be taken in patients known to have existing esophageal disease or injury or where multiple devices are placed in the esophagus at the same time.

Are the probes reusable?

No. The DPn and I2n range of probes are all Single Patient Use and are labelled accordingly.

Can EDM be used in awake patients?

The I2n range of probes are designed to be placed in unconscious patients (both anaesthetized and sedated) and then left in position after they wake up, providing the option to conduct post-operative fluid optimization. Experienced users also find these probes are well tolerated by fully conscious or lightly sedated patients. However, patients who are likely to attempt to dislodge other invasive devices, may also try to remove the EDM probe.

Can EDM be used at the same time as…?

  • Insufflation of the abdomen? Yes: EDM is unaffected by insufflation, however, changes in abdominal pressure and consequently venous return cause changes in blood flow in the descending aorta and therefore caution should be taken in interpreting these changes. Similar caution should be applied in the event of major positional change while awaiting the outcome of a fluid challenge (eg Trendelenburg).
  •  NG tubes? Yes: occasionally when using EDM with a nasogastric (NG) tube, you may notice a somewhat diminished intensity of signal. If it is in the path of the Doppler transmission, air in the NG tube can diminish the intensity of the Doppler signal (muted colours on screen). To avoid this, insert the probe before the NG tube, position the probe to the left of the already inserted NG tube, and/or flush the NG tube with saline.
  • Epidurals? Yes: however epidurals and spinal blocks cause different levels of vasodilation around the body and this may cause the derived values of stroke volume and cardiac output to change disproportionately. However, EDM’s ability to report changes and trends accurately and in the right direction is unaffected. If in doubt, manage the patient’s haemodynamics using Stroke Distance.
  • Diathermy/electro-cautery? Yes: certain models of diathermy equipment emit noise that can intermittently interfere with EDM probe, and may cause loss of signal on the monitor. If the noise is prolonged, then the average cycles per calculations can be reduced to maximize the data capture opportunity between the periods of diathermy.
  • Ultrasonic scalpels? Yes: no interference reported to date.
  • Vasopressors or vasodilators? Yes: EDM responds instantly to the effects of vasoactive agents.
  • MRI scanner? No: the probes contain a metal spring.
  • Defibrillators? Yes: EDM is insulated to protect both patient and machine. Best practice is to remove or disconnect the probe during defibrillation.