Performance Report
Redefine your quality of care with esCCO

A Novel Technology to Non-invasively MeasureContinuous Cardiac Output from ECG and SpO2

VOLUMETRIC INFORMATION FOR
ALL CARE LEVELS
Nihon Kohden is redefining Quality of Care with new, noninvasive technologies like PWTT and esCCO by introducing
volumetric information to all care levels. Estimated ContinuousCardiac Output (esCCO) is a new technology to determine thecardiac output using Pulse Wave Transit Time (PWTT). PWTT
is obtained by the familiar vital sign parameters of ECG andpulse oximetry. With esCCO, cardiac output can be measured continuously with a very simple and totally noninvasive process.
The research and development goal for esCCO was to provide volumetric information especially for midand low care levels, to improve patient care and enhance patient safety.

PULSE WAVE AND PWTT
Since the invention of pulse oximetry by Nihon Kohden researcher Takuo Aoyagi in 19741), the pulse wave
has become the most commonly used vital signal in clinical practice. The pulse wave can provide time related
information such as intravascular pressure transmission as well as information about the volume change ofarterial blood.
Pulse Wave Transit Time (PWTT) is defined as the time from the ECG R-wave peak to the pulse waverise point. The pulse wave rise point is defined as the point where the differentiated pulse wave reaches 30%
of its peak amplitude2). PWTT consists of three intervals: pre-ejection period (PEP), pulse wave transit timethrough elastic artery (T1), and pulse wave transit time through peripheral arteries (T2). PEP is defined as thetime from the ECG R-wave to the rise point of the aortic root pressure wave. T1 is defined as the time fromthe rise point of the aortic pressure wave to the rise point of the radial artery pressure wave. And T2 is definedas the time from the rise point of the radial artery pressure wave to the rise point of the pulse oximetry wave
measured by an SpO2 probe on the fingertip.
Figure 1.
Components of PWTTPEP (pre-ejection period)
T1 (PWTT through elastic artery)
T2 (PWTT through peripheral arteries)
PWTT(Pulse Wave Transit Time)

Peak of R-wave
ECG electrodes

ECG
Aortic rootpressure
Radial arterialpressure

PEPT1
100%

Differentiatedpulse oximeterwave

SpO2 probe

30%

T2

Pulse oximeter
wave
PWTT
Time

Pulse wave
rise point

PRINCIPLE OF esCCOCardiac output can be derived from pulse pressure information by the following equation:
CO = SV × HR = (K × PP) × HR
where CO = cardiac output, SV = stroke volume, HR = heart rate, K = a constant, and PP = pulse pressure
which was established in various continuous cardiac output systems using pulse contour analysis.
This was the starting point for the novel technology of esCCO. The correlation between SV and PWTT
was observed to be better than the correlation between SV and PP (Figure 2) and the following formulaprovides cardiac output values from PWTT information.
CO = SV × HR = K × (ɑ × PWTT + β) × HR = esCCO
where α and β are experimental constants.

10SV [cc]SV [cc]10

5y = 0.058 x + 15.929
r = -0.87 (p<0.001)

5y = 0.149 x + 1.968
r = 0.67 (p<0.001)
004020PP [mmHg]

600100200150
PWTT(PEP + T1 + T2) [ms]250

Figure 2. Comparison between pulse pressure (PP), pulse wave transit time (PWTT) and stroke volume (SV) of ananesthetized mongrel dog in conditions of varied circulation dynamics
Yellow circles, green triangles, and blue squares show the data at the administration of pentobarbital, the removal of blood,and the administration of phenylephrine, respectively2).

EVIDENCE BASED PERFORMANCE
In 2004, Ishihara et al. reported that esCCO derived from PWTT information is highly correlated withintermittent cardiac output determined by thermodilution (ICO)3). In 2009, a multicenter study at sevenfacilities verified the effectiveness of esCCO as a practical application. The following section describes theperformance and effectiveness of esCCO by summarizing a Euroanaesthesia 2010 presentation of themulticenter study.

esCCO Performance Report

01 - 02

Measurement Accuracy
VERIFICATION OF A NON-INVASIVECONTINUOUS CARDIAC OUTPUT MEASUREMENT METHODBASED ON THE PULSE-CONTOUR ANALYSIS COMBINEDWITH PULSE WAVE TRANSIT TIME
Presented by :	Takashige Yamada1, Yoshihiro Sugo2, Junzo Takeda1 and esCCO Research Team(Masato Tsutsui3, Tetsufumi Sato4,Toshimasa Akazawa5, Nobukazu Sato6, Koichi Yamashita7, Hironori Ishihara8)	Keio University, Department of Anaesthesiology1, Nihon Kohden Corporation2, National Defense Medical College3,Okayama University4, Juntendo University5, Toho University6, Kochi Medical School7, Hirosaki University8
Presented at : Euroanaesthesia 2010

BACKGROUND
To measure cardiac output (CO) less invasively, various devices have been developed. The esCCO (estimated(ECG-SpO2) continuous CO) measurement system (Nihon Kohden, Tokyo, Japan) is designed to measure CO
non-invasively. It estimates CO with an electrocardiogram (ECG) and a pulse oximetry waveform. 36 and 15
cases of clinical use in its development process suggest it has a good measurement accuracy equivalent toCO measured by pulmonary artery catheter (PAC)4) 5). The purpose of this study is to evaluate whether esCCO
had a sufficient accuracy for practical use in a large number of patients in multicenter settings.

METHODS
With IRB approval, 109 elective surgery patients who needed PAC insertion were enrolled. Patients who
received circulation support with artificial pacemaker or intra-aortic balloon pump were excluded. After theesCCO system and PAC installation, CO was determined by cold bolus thermodilution (ICO) and esCCO
measurements were started. Concurrently, ICO and continuous thermodilution cardiac output (CCO)
measurement was started. ICO and CCO measurements were performed periodically, once an hour in theoperation room (OR) and once a day in the intensive care unit (ICU). Data recording was continued until PAC
removal. For statistical analysis, Bland-Altman analysis and regression analysis were performed.

RESULTS
Correlation between esCCO and ICO
A total of 587 measurement pairs were obtained from 213 patients (74 in OR and 139 in ICU). The patient
demographics are shown in Table 1. Forty-six pairs were excluded as invalid data. Correlation between
esCCO and ICO was r=0.82 (p<0.01) and bias ± precision (1 standard deviation) was 0.08 ± 1.07 (L/min) in
the Bland-Altman plot (Figure 3).
There were no significant differences between mean value of esCCO and ICO (significance level: 0.05).
95% confidence intervals for bias between mean values of esCCO and ICO were 0.04 to 0.22. They are within
the range of ± 0.3 (L/min), which is considered acceptable for clinical use6).
Table 1. Patient demographics
height(cm)weight(kg)BSA(m2)CO range(L/min)Sitenduration(h)age(y)

sex(M / F)

Total

213

26.2 ± 25.2

65.1 ± 12.7

142 / 71160.0 ± 10.3

59.2 ± 12.5

1.61 ± 0.20

15.5 - 1.3

ICU

139

36.0 ± 26.2

65.7 ± 11.4

94 / 45

159.5 ± 9.9

59.4 ± 13.1

1.61 ± 0.20

15.5 - 1.5

OR74

7.6 ± 2.964.0 ± 14.8

48 / 26160.9 ± 11.058.7 ± 11.4

1.61 ± 0.19

13.1 - 1.3

16
N = 541r = 0.82 (p<0.01)
y = 0.82 × x + 0.85

126
esCCO-ICO [L/min]

14esCCO [L/min]Figure 3.
Comparison between
esCCO and ICO

810864420-2-42-60-802468

10 12 14 16

Avg = 0.08, σ = 1.07 [L/min]
02

ICO [L/min]468

10 12 14 16(esCCO+ICO)/2 [L/min]Correlation between esCCO and CCO
esCCO showed a good correlation between CCO as well. A total of 549 measurement pairs were obtained
and 45 pairs were excluded as invalid data. Correlation between esCCO and CCO was r=0.84 (p<0.01) andbias ± precision (1 standard deviation) was -0.07 ± 1.23 (L/min) in Bland-Altman plot (Figure 4). The varianceof gap increased as time passed. Some factor examinations revealed that the precision increased after
cardiopulmonary bypass (Table 2). Invalid data were related with heart manipulation and ECG abnormality

16814612410864

N = 504r = 0.84 (p<0.01)
y = 0.81 × x + 0.80

2002468

10 12 14 16

CCO [L/min]

esCCO-CCO [L/min]

esCCO [L/min](Figure 5).
Figure 4.
Comparison between
esCCO and CCO

Avg = -0.07, σ = 1.23 [L/min]

20-2-4-6-802468

10 12 14 16(esCCO+CCO)/2 [L/min]

Table 2. Accuracy change over cardiopulmonary bypass (CPB)ECG

SpO2 Pulse Wavenbias (L/min)

precision

Before CPB

22-0.415

0.998

After CPB

420.237

1.92

Figure 5.
Changes in ECG wave pattern
due to heart manipulation
esCCO Performance Report

03 - 04

Tracking Performance
ENHANCING QUALITY OF
HEMODYNAMIC MANAGEMENT WITH esCCO
Monitoring cardiac output (CO) is very important in circulation management in the operating room (OR)and intensive care unit (ICU) especially for patients with unstable hemodynamics. In this section, we will
describe one of the cases from the multicenter study to show how esCCO could be effective in hemodynamic
management.

POSTOPERATIVE CHANGE IN CARDIAC OUTPUT OF
A LIVER TRANSPLANT PATIENT IN THE ICU
Cirrhosis is accompanied by various cardiovascular abnormalities which increase cardiac output and decrease
arterial blood pressure and vascular resistance7). Therefore, perioperative monitoring of these parameters isextremely important for liver transplant patients.

Figure 6. Comparison of esCCO, ICO, CCO in ICU post liver transplantation

Figure 6 shows esCCO trend observed in a patient (36 year old male, BSA 1.87m2) in the ICU after livertransplantation. The intermittent cardiac output by cold bolus thermodilution (ICO) is shown by red triangles. TheesCCO, which was once calibrated by ICO on ICU admission, was in excellent agreement with ICO and CCO(brown line) by pulmonary artery catheter (PAC). Despite the underestimation of CO due to decreased vascularresistance, esCCO calibrated with patient information (gold line) shows an equivalent trend to CCO. Theseresults indicate that esCCO has a promising performance for tracking changes in CO after PAC removal.

RELIABLE MEASUREMENT WITH NON-INVASIVE CALIBRATION
For safe and less stressful patient care, the challenge was to avoid any kind of invasive or non-invasive
calibration. By only entering patient information such as age, gender, height and weight, and an initial NIBP
measurement, esCCO determines a reference value for calibration and is ready for start of measurement.
Additionally, a cardiac output value obtained by other CO devices such as a PAC can be used for calibration.
As shown in Figure 6, both calibration modes reliably track changes in cardiac output and provide advanced
monitoring of a patient’s hemodynamic status.

POTENTIAL APPLICATIONS OF esCCO• General monitoring of patients in OR, ICU and ER• Hemodynamic monitoring after PAC removal• Hemodynamic optimization of patients who are ineligible for PAC• Support in the decision making process for goal-directed fluid management and more
This easy and simple hemodynamic monitoring with esCCO could become a new standard for patient monitoringin every stage of patient care.

REFERENCES
1)	Severinghaus JW, Honda Y. History of blood gas analysis. 1987. VII Pulse oximetry. J Clin Monit, Apr, 3:135138.
2)	Sugo Y, Ukawa T, Takeda S, Ishihara H, Kazama T, Takeda Z. 2010. A Novel Continuous Cardiac Output
Monitor Based on Pulse Wave Transit Time. Conf Proc IEEE Eng Med Biol Soc. 2010: 2853-6.
3)	Ishihara et al. 2004. A new non-invasive continuous cardiac output trend solely utilizing routine
cardiovascular monitors. J Clin Monit, Dec, 18: 313-320.
4)	Ishihara H, Okawa H, Tanabe K, Tsubo T, Sugo Y, Akiyama T, Takeda S. 2004. A new non-invasive
continuous cardiac output trend solely utilizing routine cardiovascular monitors. J Clin Monit Comput. Dec,18 (5-6): 313-20.
5)	Tujimoto Y, Fukuda I, Ogura T, Tsutsui M, Kazama T. 2006. Comparison between esCO and intermittent
thermodilution measurement of cardiac output. Anesth Analg. 102: S-157.
6)	Lawrence C. Siegel, Maeve M. Hennessy, Ronald G. Pearl. 1996. Delayed Time Response of theContinuous Cardiac Output Pulmonary Artery Catheter. Anesth Analg 83: 1173-77.
7)	Ralph F. Lee. 2007. Cardiac dysfunction in cirrhosis. Best Practice & Research Clinical Gastroenterology,
Vol. 21, No.1: 125e140.

esCCO Performance Report

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Performance Report

Redefine your quality of care with esCCO8757 SP61-016A ’16. 7. CLB. e