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Hemodynamic optimization of the OR patient Wilbert Wesselink
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Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Jun 06, 2020

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Page 1: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Hemodynamic optimization of the OR patient

Wilbert Wesselink

Page 2: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Disclosure

Employee at Edwards Lifesciences

Page 3: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Agenda

Current practice

Hemodynamic optimization: WHY?

Hemodynamic optimization: HOW?

– Perioperative Goal Directed Therapy protocol

– Hemodynamic monitor

Continuous, minimally invasive: FloTrac

Continuous, noninvasive: ClearSight

3

Page 4: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

How many people use “flow” based technologies?

4

Page 5: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

How many people use “flow” based technologies?

5

1)Doppler?

2)Pulse Contour?

3)ECHO?

4)Something else?

Page 6: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Where do you this technology?

6

2) Intra-operative

4) Combination

3) Post-operative

1) Pre-operative

Page 7: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

WHY?

7

Page 8: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Why Hemodynamic optimization?

Complications are not exceptions

8

Page 9: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

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• 84,730 inpatients

• General or vascular surgery

• NSQIP database (designed to record

post-surgical complications until day 30)

Variation in Hospital Mortality Associated with

Inpatient Surgery. Amir A. Ghaferi, M.D., John D. Birkmeyer, M.D.,

and Justin B. Dimick, M.D., M.P.H.

N Engl J Med 2009

Page 10: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

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• Complication rate was 24.6-26.9%

• Major complication rate was 16.2-18.2%

Variation in Hospital Mortality Associated with

Inpatient Surgery. Amir A. Ghaferi, M.D., John D. Birkmeyer, M.D.,

and Justin B. Dimick, M.D., M.P.H.

N Engl J Med 2009

Page 11: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

129,233 cases

Complication rates depend on the surgical procedure

Surgery Morbidity rate %

Esophagectomy 55.1

Pelvic exenteration 45.0

Pancreatectomy 34.9

Colectomy 28.9

Gastrectomy 28.7

Liver resection 27

Prioritizing Quality Improvement

in General Surgery. Schilling et al.

J Am Coll Surg. 2008; 207:698–704.

Page 12: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

129,546 cases

Complication rates depend on the patient

Risk factor Odd ratio

ASA 4/5 vs 1/2 1.9

ASA 3 vs 1/2 1.5

Dyspnea at rest vs. none 1.4

History of COPD 1.3

Dyspnea with minimal exertion

vs. None

1.2

Successful Implementation of the

Department of Veterans Affairs’ NSQIP in the Private

Sector: The Patient Safety in Surgery Study. Khuri et al.

Ann Surg 2008

Page 13: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

WHY Hemodynamic optimization

Complications are not exceptions

Complications are costly

13

Page 14: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Extra cost $

$6358

$12802

$42790

2250 Patients Undergoing General and Vascular Surgery

Synergistic Implications of Multiple

Postoperative Outcomes. Melissa M. Boltz, DO, Christopher S. Hollenbeak, Ph.D.,

Gail Ortenzi, RN, BSN, and Peter W. Dillon, M.D.

Am J Med Quality 2012

Page 15: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Complications have a cost

15

Page 16: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

More simple and reliable approach

16

Page 17: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

More simple and reliable approach

17

+$18,000

Page 18: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

WHY Hemodynamic optimization

Complications are not exceptions

Complications are costly

Complications are responsible for prolonged LOS and readmissions

18

Page 19: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

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Page 20: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

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Page 21: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

WHY Hemodynamic optimization

Complications are not exceptions

Complications are costly

Complications are responsible for prolonged LOS and readmissions

Complications affect long-term survival

21

Page 22: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

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Page 23: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

23

Page 24: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

WHY Hemodynamic optimization?

Complications are not exceptions

Complications are costly

Complications are responsible for prolonged LOS and readmissions

Complications affect long-term survival

Hemodynamic optimization is KEY to prevent post-surgical complications

24

Page 25: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Where do we want to be?

25

Target zone

Page 26: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

HOW?

26

Page 27: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Start here

27

A large body of clinical evidence* demonstrates

If you maintain your patients in

the optimal volume range,

you can reduce

post-surgical complications,

LOS and associated costs1-4

Hemodynamically optimize your patients using:

Dynamic and flow-based parameters

A Perioperative Goal-Directed Therapy (PGDT) protocol

*35+ RCTs and 14+ meta-analyses

HOW

Too Dry Too Wet

Goal

Co

mp

lic

ati

on

s

Fluid Status High Low

Page 28: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Goal Directed Therapy

Protocols

– SV driven

– Driven by dynamic parameters like SVV

– DO2i driven

28

Page 29: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Edwards Hemodynamic Measurements From Maximal-Invasive to Non-Invasive

Invasiv

en

ess

Right Heart

Thermodilution

Swan Ganz

Transpulmonary

Thermodilution

VolumeView

Minimally Invasive

Cardiac Output

FloTrac

Non-Invasive

Cardiac Output

ClearSight

Catheter

through the

heart

One venous

and one arterial

catheter, cali-

bration needed

One arterial

catheter, auto

calibrated Finger cuff

Global trend for Hemodynamic measurements & treatments

Page 30: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

– Non Invasive Cardiac Output

• Volume Clamp Method

– Minimally Invasive Cardiac Output

• Arterial Pulse Contour Analysis

EV1000 Platform with FloTrac & ClearSight

Page 31: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Continuous minimally invasive monitoring

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Page 32: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Measuring Stroke Volume

Pulse Pressure

Vascular Tone

Compliance

Page 33: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

FloTrac Algorithm

Pulse Pressure

– Primary correlate for flow

– Pulse pressure is proportional to stroke volume

Vascular Tone

– Uses a polynomial factor called Khi for continuous assessment of waveform elements associated with changes in vasculature

Compliance

– Langewouter’s principle states that

Age, gender, height and weight inversely correlated with aortic compliance

3 basic functions of the FloTrac algorithm for calculating stroke volume

Page 34: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

FloTrac System Algorithm Evolution Continuing to Better Meet the Needs of More Patients

1st Generation Algorithm

• Introduced Automatic Vascular Tone Adjustment (10 min avg)

• Data base Patients: primarily cardiac patients

2nd Generation Algorithm

• Improved Automatic Vascular Tone Adjustment (1 min avg)

• Added fluid optimization screen enhancements

• Data Base Patients: includes high risk surgical patients

Next Generation Algorithm (SVVxtra)

• Adjusts for certain types of arrhythmias

3rd Generation Algorithm

• Adjusts for hyperdynamic patients

• Includes certain sepsis patients and liver resection

2011 2008 2006 2005

Page 35: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

FloTrac 4.0 Algorithm update

This update to the FloTrac system algorithm has allowed for the improved measurement of rapid, but transient, changes in tone and pressure.

To better account for vaso-active drugs

To have less correlation with MAP and SVR

Nexfin

FloTrac

FT-NexGen

565 570 575 580 585 590

3.5

4

4.5

5

5.5

6

6.5

7

7.5

8

Time (minute)

CO

(L/m

in)

2011030168

Nexfin

FloTrac

FT-NexGenVaso Vaso

Simulation based on captured pressure data

Page 36: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Continuous, noninvasive monitoring

36

Page 37: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

History

Volume clamping invented by Jan Peňáz1, Physiocal invented by Karel Wesseling2

Product evolution over the years:

– From finger pressure to reconstructed brachial pressure3

– Blood pressure calibration using NIBP no longer needed4

– CO determination using physiological model of the circulation

Page 38: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

The essence is to dynamically provide

equal pressures on either side of the wall of the

artery by clamping the artery to a

certain constant volume1

The ClearSight system uses a finger cuff with a

photoplethysmograph to monitor arterial

volume and an inflatable

bladder to apply the required pressure

BP measurement using Volume Clamping

The essence is to dynamically provide

equal pressures on either side of the wall of the

artery by clamping the artery to a

certain constant volume1

The ClearSight system uses a finger cuff with a

photoplethysmograph to monitor arterial volume and

an inflatable

bladder to apply the required pressure

Page 39: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

BP measurement using Volume Clamping

1000 times each second the cuff pressure is adjusted to keep the diameter of the finger arteries constant (volume clamping)

Continuous recording of the cuff pressure results in real-time finger pressure waveform

Plethysmograph

Lightsource Lightdetector

Inflatable bladder Infrared Light

Page 40: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Normal situation

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Page 41: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Measuring arterial volume

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Page 42: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Applying volume clamping

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Page 43: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Volume clamp control loop

43

Page 44: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Physiocal Method

Physiological calibration of the blood pressure is performed by Physiocal

Physiocal is the real-time expert system that determines the proper arterial ‘unloaded’ volume, i.e. no pressure gradient across the arterial wall2

Periodic adjustments are essential to track the unloaded volume when smooth muscle tone changes

Page 45: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Physiocal Method

Physiocal periodically recalibrates the system and allows accurate tracking of significant changes in the physiology

Volume change

Pressure wave Physiocal

a b d c

Page 46: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Pressure Waves Along Arterial Tree

100

80

60

0.4 0.8

Pre

ssu

re [m

mH

g]

Time [s]

Brachial 100

80

60

0.4 0.8

Pre

ssu

re [m

mH

g]

Time [s]

Finger 100

80

60

0.4 0.8

Pre

ssu

re [m

mH

g]

Time [s]

Radial

Page 47: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Brachial Pressure Reconstruction

The brachial pressure is reconstructed from the finger pressure in 2 steps3:

– Shape: Finger pressure is transformed into brachial pressure using a transfer function

– Level: Correction for brachial-finger pressure gradient

Finger pressure

Brachial pressure

Page 48: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Without HRS – Heart Reference Sensor

Page 49: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

With HRS – Heart Reference Sensor

Page 50: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Widely used by physiologists

50

Page 51: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Even on top of the world….

51

Page 52: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

… and beyond

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Page 53: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Does it work in the OR?

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Page 54: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

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Page 55: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

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Not Identical, but close, i.e.

Mean Arterial Pressure (MAP):

• Accuracy 2.2 mmHg

• Precision 6.4 mmHg

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Not Identical, but close, i.e.

Mean Arterial Pressure (MAP):

• Accuracy 2.2 mmHg

• Precision 6.4 mmHg

Page 57: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

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Within AAMI: 5±8 mmHg

Page 58: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Clinical example

Edwards internal data on file. The data was collected during the BMEYE due diligence and is accurately represented in the attached slides to

the best of my knowledge - Feras Hatib, PhD, Distinguished Engineer, Discovery, Critical Care

Interesting Points: • Nexfin technology

rapidly applied &

functioning

• Good correlation with

Arterial line

• Cuff measurement less

accurate

Page 59: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Blood Pressure ≠ Blood Flow

59

Page 60: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

From Pressure to Flow

Blood pressure (P) and flow (Q) result from the interaction of the heart as a pump and the arterial system as its afterload (Zin)

Pulse contour methods use this close interaction in the hemodynamic version of Ohms law:

ΔP/Q = Zin

When afterload can be determined,

flow can be calculated from pressure:

Q = ΔP/Zin

Page 61: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Stroke volume calculation

In order to determine stroke volume and cardiac output from noninvasive continuous blood pressure, a pulse contour method based on a physiological model of the circulation is used4

61

The systolic pressure-time integral ∫[P(t)-Pd]dt

140

120

80

1

100

Pre

ssu

re [m

mH

g]

Time [s]

The 3-element Windkessel model to calculate after-load using patient age, gender, height and weight

2. 1.

Page 62: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Cardiac output

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Page 63: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Non invasive opportunity for PGDT

Patients without arterial line, but at risk for complications

Examples

– Abdominal surgery

– Femur/hip fracture surgery

– Bariatric surgery

– C-section

Other: spinal anesthesia

63

Su

rgic

al R

isk

ASA I-II < 65 → ASA > II & 65

ClearSight FloTrac

Basic Monitoring ClearSight

Page 64: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

Takeaway

Post-surgical complications are:

– No exceptions

– Costly

– Increase LOS and readmission

– Affect long term survival

Hemodynamic optimization is the key to reduce post-surgical complications and requires:

– Cardiac output monitoring

– Perioperative Goal Directed Theray protocol

ClearSight and FloTrac both are well validated technologies to support hemodynamic optimization of the OR patient

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Page 66: Hemodynamic optimization of the OR patient optimization of the OR patient...Hemodynamic optimization is the key to reduce post-surgical complications and requires: –Cardiac output

References 1. Peñáz J Photoelectric measurement of blood pressure volume and flow in the finger. In: Digest of the 10th International Conference on

Medical and Biological Engineering; Dresden; 1973; 104 2. Wesseling KH, de Wit B, van der Hoeven GMA, van Goudoever J, Settels JJ Physiocal, Calibrating Finger Vascular Physiology for

Finapres, Homeostasis 36:67-82, 1995 3. Gizdulich P1, Prentza A, Wesseling KH, Models of brachial to finger pulse wave distortion and pressure decrement, Cardiovasc Res.

1997 Mar;33(3):698-705 4. Truijen J, van Lieshout JJ, Wesselink WA, Westerhof BE, Noninvasive continuous hemodynamic monitoring, J Clin Monit Comput. 2012

Aug;26(4):267-78 5. Martina JR, Westerhof BE, van GJ, de Beaumont EM, Truijen J, Kim YS, Immink RV, Jobsis DA, Hollmann MW, Lahpor JR, et al.

Noninvasive continuous arterial blood pressure monitoring with Nexfin. Anesthesiology 2012 May;116(5):1092-103 6. Wax DB, Lin HM, Leibowitz AB, Invasive and concomitant noninvasive intraoperative blood pressure monitoring: observed differences in

measurements and associated therapeutic interventions, Anesthesiology. 2011 Nov;115(5):973-8 7. Vos JJ, Poterman M, Mooyaart EA, Weening M, Struys MM, Scheeren TW, Kalmar AF. Comparison of continuous non-invasive finger

arterial pressure monitoring with conventional intermittent automated arm arterial pressure measurement in patients under general anaesthesia. Br.J Anaesth. 2014 Jul;113(1):67-74.

8. Weiss E, Gayat E, Dumans-Nizard V, Le Guen M, Fischler M, Use of the Nexfin™ device to detect acute arterial pressure variations during anaesthesia induction, Br J Anaesth. 2014 Jul;113(1):52-60

9. Chen G, Chung E, Meng L, Alexander B, Vu T, Rinehart J, Cannesson MJ, Impact of non invasive and beat-to-beat arterial pressure monitoring on intraoperative hemodynamic management, Clin Monit Comput. 2012 Apr;26(2):133-40

10. Walsh M, Devereaux PJ, Garg AX, Kurz A, Turan A, Rodseth RN, Cywinski J, Thabane L, Sessler DI, Relationship between intraoperative mean arterial pressure and clinical outcomes after noncardiac surgery: toward an empirical definition of hypotension, Anesthesiology

11. Broch O, Renner J, Gruenewald M, Meybohm P, Schottler J, Caliebe A, Steinfath M, Malbrain M, Bein B. A comparison of the Nexfin and transcardiopulmonary thermodilution to estimate cardiac output during coronary artery surgery. Anaesthesia 2012 Apr;67(4):377-83.

12. Bubenek-Turconi SI, Craciun M, Miclea I, Perel A. Noninvasive Continuous Cardiac Output by the Nexfin Before and After Preload-Modifying Maneuvers: A Comparison with Intermittent Thermodilution Cardiac Output. Anesth Analg. 2013 Jun 11

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