User’s Report

Hemodynamic Management Using esCCO

Ryoichi Ochiai, MD, PhD
Emeritus Professor, Toho University(Department of Anesthesiology, Toho University School of Medicine, Tokyo, Japan)

This report presents an interview with Dr. Ryoichi Ochiai, who has been
involved in clinical research on esCCO for many years, about his opinionof hemodynamic management and treatment strategies using esCCO.

Introduction – what is esCCO?

Estimated Continuous Cardiac Output (esCCO) is Nihon Kohden’s original technology that provides noninvasive and continuous measurements of cardiac output using only routinely monitored parameters of ECG,SpO2, and NIBP. Stroke volume is determined based on the time from the ECG R-wave to the rise point of theSpO2 pulse wave (PWTT*) (Figure 1), and cardiac output is calculated from a product of stroke volume andheart rate. *PWTT: Pulse Wave Transit Time
ECG
electrodes

R-waveECGTimePulse oximeterwaveform
SpO 2 probe

Rise pointof pulse wavePWTT

Figure 1 Pulse wave transit time (PWTT) obtained from ECG and pulse oximeter waveform

Maintenance of organ blood flow is important inpreventing organ ischemia. The vital organs havea mechanism called autoregulation to maintain thenecessary blood flow. In healthy individuals, thisautoregulation functions over a very wide range of theperfusion pressure from 50 to 150 mmHg to maintainblood flow.
In contrast, blood flow reduces outside the range ofautoregulation, in other words, below the lower limit ofblood pressure, to cause organs to fall into an ischemic
state. In addition, blood flow increases above the upper
limit to increase the risk of edema or bleeding. Therefore,
the goal of hemodynamic management during anesthesia
is to maintain blood pressure within the range of theautoregulation mechanism (Figure 2).

Blood flow rate [mL/100g/min]Please tell us about the goal of hemodynamic management during anesthesia.

1007550

Range of autoregulation
250050100

150200Perfusion pressure [mmHg]

Figure 2 Autoregulation of organ perfusion

250

User’s Report

Blood pressure management is important.
How is the cause of decreased blood pressure diagnosed?
Blood pressure is determined by a product of blood flow and vascular resistance. Thus, a decrease in either
blood flow or vascular resistance leads to a decrease in blood pressure. Blood flow is represented by cardiac
output, and cardiac output monitoring is very important in managing blood pressure.
A decrease in cardiac output can occur in case of either a decrease in myocardial contraction or a decrease inblood returning to the heart. In such cases, myocardial contraction is represented by stroke volume and is a
useful parameter in narrowing down the range of causes of decreased blood pressure.

Why is monitoring of both stroke volume and cardiac output necessary?

If hypotension does not improve even in
the presence of an appropriate preload,
an assessment of cardiac output allows
selection of treatment approaches.
As the fluid-challenge has ruled out thefactor of a deficiency in circulating blood
volume, a determination of whether
to contract blood vessels or increase
myocardial contraction to improvehypotension can be made based on anassessment of cardiac output, a measureof hemodynamic status such as cardiac
function, and afterload (Figure 4).
A combination of real-time monitoringof stroke volume, cardiac output, andblood pressure with the fluid-challengeallows an early diagnosis of the factor of
unexpected decreased blood pressure andenables rapid formulation of treatment
strategies.
Because an unexpected decrease inblood pressure can occur in either lowrisk surgery or surgery under local
anesthesia, I think that the introductionof esCCO enables constant monitoringof these parameters in all cases to createa safer surgical environment.

Responsivenessto fluid

Responsivenessto fluid

Positive

Negative

Normal heart

Stroke volume

When blood pressure decreases, preload,in other words, circulating blood
volume, needs to be assessed but cannot
be assessed with central venous pressure.
Thus, it is important that fluid-challenge
is performed to determine how strokevolume responds. Excess and deficiencyof the preload are checked by assessingchanges in stroke volume at the start andend of fluid-challenge using a FrankStarling curve (Figure 3).

Failing heart

00

Cardiac preload

Figure 3 Frank-Starling curve

Decreased blood pressure
Cardiac failure?
Decreased circulating blood volume?
Dilatation of peripheral vessels?

SV monitoring(esCCO monitoring)[SVI 25 to 50 mL/m²]

Unknown
circulating blood volume

Fluid-challenge[300 mL/15 mins]

SVI > 10%Decreased
circulating blood volume

Fluid therapy

SVI < 10%
CI < 2.5 L/min/m
Adequate
circulating blood volume2

Cardiac failure

CI > 2.5 L/min/m2
Dilatation of
peripheral vessels

Dopamine administration
Dobutamine administration

Noradrenaline
administration

Figure 4 An example of hemodynamic management protocolsVarious methods for measuring stroke volume are available.
Please tell us about current issues.
Thermodilution using a Swan-Ganz’s catheter has been widely used, but is highly invasive and very poor inresponsiveness to continuous measurement, which were regarded as issues. Thus, arterial pressure waveform
analysis using invasive arterial pressure waveforms has been in widespread use, but is not non-invasive becauseof the need to establish an arterial pressure line.
Just like thermodilution, arterial pressure waveform analysis also requires dedicated medical supplies and seems
to have challenges in terms of both invasiveness and economic potential.

In contrast, esCCO, which is a PWTT analysis using ECG, SpO2, and NIBP, provides non-invasive andcontinuous measurements of stroke volume (Table 1, Figure 5). The standard and non-invasive parameter
providing information on stroke volume brings about advantages from a variety of aspects, including prognosis
and improvement in QOL of patients, reduction in the burden on healthcare providers, and medical costsavings. In addition, I think that these advantages
Non-invasiveare very important in addressing an aging population
progressing at an accelerated pace.
PWTT analysis

Table 1 Features of PWTT analysis (esCCO)

Features of PWTT analysis esCCO
Intermittent

A technology that estimates cardiac output based on thetime from the ECG R-wave to the rise point of the pulse
oximeter wave (PWTT)

ContinuousThermodilution

Arterial pressure
waveform analysis

Measured using routinely monitored parameters of ECG,
SpO 2, and NIBP
Provides non-invasive and continuous measurements ofstroke volume

Invasive

Figure 5 Position of cardiac output measurement technology

How does the use of esCCO change hemodynamic management in theperioperative period?
As previous measurement methods are highly invasive and require dedicated medical supplies, hemodynamic
management using cardiac output has been limited to patients with a cardiovascular risk or very high-risk surgeries.
If decreased blood pressure occurs in low-risk surgeries, which do not usually involve cardiac output monitoring,the current situation is that many physicians perform fluid and hemodynamic managements dependent on theirown experience or skills in consideration of effects on patients’ QOL or increase in cost. However, the allowable
range of fluid therapy in high risk groups, such as elderly people, is very narrow, and extreme caution is needed
to prevent complications (Figure 6).

I think that the use of esCCO provides real-time monitoring of stroke volume and cardiac output based on ECG,
SpO2, and NIBP, and the parameters routinely used in usual surgeries allows more accurate and safer fluid andhemodynamic managements.

Risk for complications

esCCO is a non-invasive monitoring tool and is therefore expected to contribute to improvement in the QOL ofpatients and will have beneficial effects on the prognosis. In addition, there is no need to prepare additional devices
or separate equipment, which leads to a reduction in the burden on perioperative care staff and prevents increases incost. I think that the esCCO technology,
which provides an environment for
constant monitoring of cardiac output Inadequate fluid
Excessive fluid
Tissue edema
and stroke volume in patients under local Low tissue perfusion
Organ failure
Tissue hypoxia
anesthesia, as well as patients under Organ failure
Increased length of staygeneral anesthesia, has the potential
Increased mortality
Allowable range
to change anesthesia management andis of significant value in terms of both
Fluid volume
activities within the department ofanesthesiology and health economics.
Figure 6 Relationship between fluid volume and risk for complications

User’s Report
Dr. Ochiai has put efforts into global dissemination and education on high-quality
hemodynamic management, including holding seminars on hemodynamic managementin Vietnam. Please let us know about hemodynamic management using esCCO.
I have provided support to developing countries for at least three years and found that there are many countries
with limited healthcare resources. I think that use of esCCO provides high-quality hemodynamic managementthat could not be achieved previously in such countries that cannot spend so much on medical costs.
In contrast, the population is aging and decreasing in Japan. In the context of the need for medical cost savings
while ensuring therapeutic efficacy, I think that a new parameter that is non-invasive and requires no additionalcosts, such as esCCO, may be appreciated.

Seminar in Vietnam

With participants after the seminar

Finally, please send a message to physicians in other institutions.
esCCO is a technology that provides non-invasive and continuous monitoring of cardiac output and can bea parameter that enables a new hemodynamic management featuring stroke volume. Please try to perform
hemodynamic management with monitoring of blood pressure and stroke volume.

Thank you, Dr. Ochiai.

10205 SP70-0019 '21.1. CLB. PDF