Hemodynamic optimization of the OR patient. Wilbert Wesselink

Transcription

1 Hemodynamic optimization of the OR patient Wilbert Wesselink

2 Disclosure Employee at Edwards Lifesciences

3 Agenda Current practice Hemodynamic optimization: WHY? Hemodynamic optimization: HOW? Perioperative Goal Directed Therapy protocol Hemodynamic monitor Continuous, minimally invasive: FloTrac Continuous, noninvasive: ClearSight 3

4 How many people use flow based technologies? 4

5 How many people use flow based technologies? 1)Doppler? 2)Pulse Contour? 3)ECHO? 4)Something else? 5

6 Where do you this technology? 1) Pre-operative 2) Intra-operative 3) Post-operative 4) Combination 6

7 WHY? 7

8 Why Hemodynamic optimization? Complications are not exceptions 8

9 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 ,730 inpatients General or vascular surgery NSQIP database (designed to record post-surgical complications until day 30) 9

10 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 Complication rate was % Major complication rate was % 10

11 Prioritizing Quality Improvement in General Surgery. Schilling et al. J Am Coll Surg. 2008; 207: ,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

12 Successful Implementation of the Department of Veterans Affairs NSQIP in the Private Sector: The Patient Safety in Surgery Study. Khuri et al. Ann Surg ,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

13 WHY Hemodynamic optimization Complications are not exceptions Complications are costly 13

14 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 Patients Undergoing General and Vascular Surgery Extra cost $ $42790 $6358 $12802

15 Complications have a cost 15

16 More simple and reliable approach 16

17 More simple and reliable approach +$18,000 17

18 WHY Hemodynamic optimization Complications are not exceptions Complications are costly Complications are responsible for prolonged LOS and readmissions 18

19 19

20 20

21 WHY Hemodynamic optimization Complications are not exceptions Complications are costly Complications are responsible for prolonged LOS and readmissions Complications affect long-term survival 21

22 22

23 23

24 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

25 Where do we want to be? Target zone 25

26 HOW? 26

27 Complications Start here 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 costs 1-4 Too Dry Too Wet Goal Low Fluid Status High *35+ RCTs and 14+ meta-analyses HOW Hemodynamically optimize your patients using: Dynamic and flow-based parameters A Perioperative Goal-Directed Therapy (PGDT) protocol 27

28 Goal Directed Therapy Protocols SV driven Driven by dynamic parameters like SVV DO2i driven 28

29 Invasiveness Edwards Hemodynamic Measurements From Maximal-Invasive to Non-Invasive Catheter through the heart One venous and one arterial catheter, calibration needed One arterial catheter, auto calibrated Finger cuff Right Heart Thermodilution Transpulmonary Thermodilution Minimally Invasive Cardiac Output Non-Invasive Cardiac Output Swan Ganz VolumeView FloTrac ClearSight Global trend for Hemodynamic measurements & treatments

30 EV1000 Platform with FloTrac & ClearSight Minimally Invasive Cardiac Output Arterial Pulse Contour Analysis Non Invasive Cardiac Output Volume Clamp Method

31 Continuous minimally invasive monitoring 31

32 Measuring Stroke Volume Pulse Pressure Vascular Tone Compliance

33 FloTrac Algorithm 3 basic functions of the FloTrac algorithm for calculating stroke volume 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

34 FloTrac System Algorithm Evolution Continuing to Better Meet the Needs of More Patients 1 st Generation Algorithm Introduced Automatic Vascular Tone Adjustment (10 min avg) Data base Patients: primarily cardiac patients 2 nd Generation Algorithm Improved Automatic Vascular Tone Adjustment (1 min avg) Added fluid optimization screen enhancements Data Base Patients: includes high risk surgical patients 3 rd Generation Algorithm Adjusts for hyperdynamic patients Includes certain sepsis patients and liver resection Next Generation Algorithm (SVVxtra) Adjusts for certain types of arrhythmias

35 CO (L/min) 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 Vaso Vaso Nexfin FloTrac FT-NexGen Nexfin FloTrac FT-NexGen Simulation based on captured pressure data Time (minute)

36 Continuous, noninvasive monitoring 36

37 History Volume clamping invented by Jan Peňáz 1, Physiocal invented by Karel Wesseling 2 Product evolution over the years: From finger pressure to reconstructed brachial pressure 3 Blood pressure calibration using NIBP no longer needed 4 CO determination using physiological model of the circulation

38 BP measurement using Volume Clamping The The essence is to dynamically provide equal pressures on either side of the wall of of the the artery by clamping the artery to to a a certain constant volume 1 1 The The ClearSight system uses a finger cuff cuff with with a a photoplethysmograph to monitor arterial volume an and inflatable an inflatable bladder to to apply the required pressure photoplethysmograph to monitor arterial volume and

39 BP measurement using Volume Clamping Plethysmograph Inflatable bladder Infrared Light Lightsource Lightdetector 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

40 Normal situation 40

41 Measuring arterial volume 41

42 Applying volume clamping 42

43 Volume clamp control loop 43

44 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 wall 2 Periodic adjustments are essential to track the unloaded volume when smooth muscle tone changes

45 Physiocal Method Physiocal periodically recalibrates the system and allows accurate tracking of significant changes in the physiology Volume change a b c d Physiocal Pressure wave

46 Pressure [mmhg] Pressure [mmhg] Pressure [mmhg] Pressure Waves Along Arterial Tree 100 Brachial 100 Radial 100 Finger Time [s] Time [s] Time [s]

47 Brachial Pressure Reconstruction Brachial pressure Finger pressure The brachial pressure is reconstructed from the finger pressure in 2 steps 3 : Shape: Finger pressure is transformed into brachial pressure using a transfer function Level: Correction for brachial-finger pressure gradient

48 Without HRS Heart Reference Sensor

49 With HRS Heart Reference Sensor

50 Widely used by physiologists 50

51 Even on top of the world. 51

52 and beyond 52

53 Does it work in the OR? 53

54 54

55 Not Identical, but close, i.e. Mean Arterial Pressure (MAP): Accuracy 2.2 mmhg Precision 6.4 mmhg 55

56 Not Identical, but close, i.e. Mean Arterial Pressure (MAP): Accuracy 2.2 mmhg Precision 6.4 mmhg 56

57 Within AAMI: 5±8 mmhg 57

58 Clinical example Interesting Points: Nexfin technology rapidly applied & functioning Good correlation with Arterial line Cuff measurement less accurate 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

59 Blood Pressure Blood Flow 59

60 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 (Z in ) Pulse contour methods use this close interaction in the hemodynamic version of Ohms law: ΔP/Q = Z in When afterload can be determined, flow can be calculated from pressure: Q = ΔP/Z in

61 Pressure [mmhg] 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 used 4 1. The systolic pressure-time integral [P(t)-Pd]dt The 3-element Windkessel model to calculate after-load using patient age, gender, height and weight Time [s] 1 61

62 Cardiac output 62

63 Surgical Risk 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 ClearSight Basic Monitoring FloTrac ClearSight Other: spinal anesthesia ASA I-II < 65 ASA > II & 65 63

64 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 64

65 65

66 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; 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, Gizdulich P1, Prentza A, Wesseling KH, Models of brachial to finger pulse wave distortion and pressure decrement, Cardiovasc Res Mar;33(3): Truijen J, van Lieshout JJ, Wesselink WA, Westerhof BE, Noninvasive continuous hemodynamic monitoring, J Clin Monit Comput Aug;26(4): 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): Wax DB, Lin HM, Leibowitz AB, Invasive and concomitant noninvasive intraoperative blood pressure monitoring: observed differences in measurements and associated therapeutic interventions, Anesthesiology Nov;115(5): 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 Jul;113(1): 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 Jul;113(1): 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 Apr;26(2): 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): 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 Jun 11 66

67