1. Case Studies in Hemodynamics Angela Craig APN, MS, CCNS Clinical Nurse Specialist of ICU Cookeville Regional Medical Center Cookeville, TN

2. Right monitor for the Right Patient
“An improved understanding of these emerging technologies will assist the intensivist in applying the appropriate device to his or her particular setting.”
Chaney & Derdak Crit Care Med 2002 2

3. Marik, CCM Journal 10/2016
“Emerging boy of evidence suggests that aggressive fluid resuscitation leads to severe tissue edema that compromises organ function and leads to increased morbidity and mortality”

4. Marik, CCM Journal 10/2016
“Recent global cohort study that evaluated the approach to fluid resuscitation in 46 countries concluded that the current practice and evaluation of fluid management in critically ill patients seem to be arbitrary….. Is not evidence-based and could be harmful”

5. Marik, CCM Journal 10/2016
“Fundamentally, the only reason to give a patient a fluid challenge is to increase their stroke volume (SV); if this does not happen, fluid administration serves no useful purpose and is likely to be harmful”

6. Traditional measures… Are they enough??
“It should be recognized that systemic hypo-perfusion usually precedes hypotension, especially in patients with sepsis.” Rackow, JAMA 1991
MAP: slow to respond, does not tell the full story…
“The most rudimentary measure used to assess fluid responsiveness is the mean arterial pressure (MAP), but this value alone provides little useful information regarding actual blood flow or oxygen delivery. Anesth Analg., 2005
Assumptions:
Assumption P=F
Blood Pressure reflects flow
MAP = CO
If BP goes up… then CO goes up
If CO is down… then BP is down
is really a
MISCONCEPTION

7. MICROCIRCULATION: SUBLINGUAL BLOOD FLOW
Healthy Volunteer
BP: 120/80 mm Hg
SaO2: 98%
Septic Shock Patient
Resuscitated with fluids and dopamine
HR: 82 BPM
BP: 90/35 mmHg
SaO2: 98%
CVP: 25 mmHg
1. Accessed April Spronk PE, et al. Lancet. 2002;360:

8. Traditional measures… Are they enough??
“Although vital signs help assess the adequacy of tissue perfusion, they are a late indicator of tissue ischemia.”
MAP UO HR
Spo2
ScV02
SVV
“Analysis of hemodynamic variables beyond traditional measures allows the clinician to differentiate various causes of hemodynamic instability and intervene appropriately...."
SV/SVI
CO/CI
SVR/SVRI

9. Tissue Perfusion SCVO2 SVO2

10. Principles of Oxygen Delivery and Consumption
Arterial oxygen delivery (DO2) – amount of oxygen delivered to the tissues in mL of Oxygen/min
Oxygen consumption (VO2) - amount of oxygen consumed by the tissues
SVO2 Oximetric PA catheter
SCVO2 Oximetric Central Venous Catheter or intermittent
SVo2/Scvo2 decreases when o2 delivery is compromised or o2 demands exceeds supply

11. SCVO2 = Oxygen Saturation of Central venous blood located in the superior vena cava
Requires a Catheter for Continuous monitoring OR a central line for intermittent readings
Reflects balance between oxygen delivery (DO2) and O2 demands by the tissues

12. Principles of Oxygen Delivery and Consumption
Imbalance trigger compensatory mechanisms
Increased CO and Increased O2 extraction
Failure to restore balance  anaerobic metabolism, lactic acidosis, and global tissue hypoxia
SVO2  global indicator of balance between O2 delivery and O2 demand
ScvO2 convenient surrogate for SVO2 (ScvO2 trend with SVO2)

13. Benefits of ScvO2
Global indicator of balance between oxygen supply and demand
Indicator of detecting Blood loss
Decrease can detect occult tissue hypoxia

14. Significance of ScvO2 Influenced by: Cardiac Output Hemoglobin
Arterial saturation (SaO2)
Oxygen Consumption (VO2)
(Lets “CHAT” about it C=CO, H=Hgb, A=Art sat, T= Tissue Oxygen Demands/Consumption)
Look at these 4 factors to assess changes in ScvO2

16. ScvO2

17. When should I be concerned?
ScvO2 <70% or Elevated
Change of +/- 5-10% in short time period
ScvO2 <50% cells switch from aerobic to anaerobic metabolism

18. Other Variables
CO/CI
SVV/PVI/PPV
SV/SVI
SVR/SVRI

19. Square Wave Test
Figure A: Expected square wave test (1-2 oscillations before returning to baseline)
Figure B:
Over damped:
(less than 1 oscillation) underestimate
SBP and overestimate DBP)
Figure C:
Under damped
(>2 oscillations overestimate SBP
Underestimate DBP)

21. Hemodynamic Monitoring Determinants of Cardiac Output
Cardiac Output (CO)
Stroke Volume (SV) x Heart Rate (HR)
Heart Rate
Stroke Volume
Afterload
(Squeeze)
Preload
(Volume)
Contractility
(Pump)

22. Hemodynamic Monitoring
Preload
Volume status
Currently measured by CVP, PAOP (PCW)
SVV /PPV/ PVI (When appropriate – limitations)
Assess Urine Output

23. Pulsus Paradoxus: The Origin of SVV
Pulses Paradoxus is the origin of SVV value.
Occurs with spontaneously breathing patients.
Reverse Pulses Paradoxus
Occurs during positive pressure ventilation.
Clinical use of this phenomenon remains “marginal”.
Michard cited
See AR01317
Michard Anesthesiology 2005 23

24. Video Clip https://www.youtube.com/watch?v=ew0H6eTrt90

25. What is Stroke Volume Variation??25

26. What is Stroke Volume Variation??
Stroke Volume Variation literally is a calculated percentage of variation between the Stroke Volumes…
9/13/2018 26

27. Two Major Indications of SVV:
1. evaluate the response to fluid interventions
2. determine or predict the patient’s potential response to fluid therapy
If variability is low (SVV <15%), need for fluid low
If variability is high (SVV > 15%), need for fluid is high
Michard, Teboul
Michard 1999, & 2005, Teboul 2003 27

28. Stroke Volume (SV) Stroke Volume Index (SVI)
SV (COX1000÷HR)
Blood ejected from the left ventricle per beat
Norm= mL/beat
SVI (SV÷BSA)
SV divided by body surface area
Norm = 35-47

29. Requirements to utilize Stroke Volume Variation:
Mechanical Ventilation
Currently, literature supports the use of SVV only on patients who are 100% mechanically (control mode) ventilated with tidal volumes of 8-10cc/kg and fixed respiratory rates.
Spontaneous Ventilation
Currently, literature does not support the use of SVV with patients who are spontaneously breathing due to the irregular nature of rate and tidal volumes.
Arrhythmias
Arrhythmias can dramatically affect SVV values. Thus, the utility of SVV as a guide for volume resuscitation is greatest in absence of arrhythmias.
PEEP
Increasing levels of positive end expiratory pressure (PEEP) may cause an increase in SVV, the effects of which may be corrected by additional volume resuscitation if warranted. 29

30. Pulse Pressure Variation PPV
(PPmax – PPmin) / PPmean over a respiratory cycle or other period of time.
SVV or PPV >10% suggests that the patient is fluid responsiveness
Remember limitations based on your care area
Michard cited
See AR01317 30

31. Pleth Variability Index (PVI)
Michard cited
See AR01317 31

32. Stroke Volume Variation (SVV) Pleth Variability Index (PVI) Pulse Pressure Variation (PPV)
Limitations:
Presence of arrhythmias
use of differing tidal volumes & rates
Control Mode Ventilation
At least 8mL/kg TV
non mechanically-control ventilated patients limits the predictive value of SVV.

33. Marik, CCM Journal 10/2016
“A patient is considered to be fluid responsive is his/her SV increases by at least 10% following a fluid challenge (usually 500mL of crystalloid)”

34. For ICU Setting SV can be more helpful
Utilize only SVI when your patient is extubated or ventilator settings are not optimized for SVV.
ALWAYS assess SVV and SVI together.

35. Marik, CCM Journal 10/2016
“Not all patients need to be on the flat portion of their Frank Starling Curve”
“Most healthy humans are normally fluid responsive and function on the ascending limb of the Frank-Starling Curve”

36. Marik, CCM Journal 10/2016
“Pts should only receive a fluid bolus if they are preload responsive and likely to benefit from the fluid bolus, that is, the potential benefit and risk should be evaluated prior to each fluid bolus”

40. Optimize Cardiac Performance
Fluid Bolus to define place on curve:
Record SV
Give NS bolus over 15minutes
If see greater than a 10% increase in SV pt is on steep portion of curve and will still respond to fluid

41. Hemodynamic Monitoring
Contractility (Pump)
How effectively the heart is pumping
What is the patients ejection fraction??
CO= SV x HR
Normal:
CO= 4-8 L;
CI=2.5-4 L;
SV= ml;
SVI=33-47 ml

42. Stroke Volume (SV) Stroke Volume Index (SVI)
SV (COX1000÷HR)
Blood ejected from the left ventricle per beat
Norm= mL/beat
SVI (SV÷BSA)
SV divided by body surface area
Norm = 35-47

43. Hemodynamic Monitoring
Afterload (Squeeze)
Resistance that heart has to pump against
Currently use SVR which is a calculated variable
Normal:

44. Systemic Vascular Resistance (SVR) Systemic Vascular Resistance Index (SVRI)
SVR (MAP-CVP/RAP x 80÷CO)
clinical indicator of afterload
resistance to ejection of blood during left ventricular contraction
Norm = dynes/sec
SVRI (MAP-CVP/RAP x 80÷CI)
SVR divided by body surface area
Norm =

45. Optimize Cardiac Performance
Fluid Bolus to define place on curve:
Record SV
Give NS bolus over 15minutes
If see greater than a 10% increase in SV pt is on steep portion of curve and will still respond to fluid

46. CLOSE ALL NOTEBOOKS
Its Practice TIME!!!! 

47. Right Monitoring For the Right Patient at the Right Time
Right Monitoring For the Right Patient at the Right Time!! It is essential we make the best decision for our patients!!

48. Practice:
A: Blue Volume Issue (Think Preload) B: Red Pump Issue (Think Contractility) C: Yellow Squeeze Issue (Think Afterload) D: Green None of the Above – lets talk about another option

49. Practice
55y/o Female, 4 day history of pain and swelling in the Rt arm. On Exam Temp 38.4 (101 degrees) Pulse 120, B/P 100/55, RR 22 min, arm edematous, indurated, tender and ascending inflammation, necrotic fasciitis Pt went for emergency exploration of the Rt arm Received 500mL LR prior to anesthesia Has art line, 2 peripheral Ivs,

50. 30 min after pt arrived to ICU
B/p 85/40
MAP 55
HR 130
U/O <0.25mL/Kg in last 30 minutes
EBL 200
What is your Gut feet Feel?

51. What is the Patient Issue?
A: Blue Volume Issue (Think Preload) B: Red Pump Issue (Think Contractility) C: Yellow Squeeze Issue (Think Afterload) D: Green None of the Above – lets talk about another option

52. Once Hemodynamic Variables Obtained
SCVO2 65 SVV 17 CVP 5 Urine Output remains low CO 2.6 SV 50

53. What is the Patient Issue?
A: Blue Volume Issue (Think Preload) B: Red Pump Issue (Think Contractility) C: Yellow Squeeze Issue (Think Afterload) D: Green None of the Above – lets talk about another option

54. How Can We Best Optimize the Pt?
A: Blue Stroke Volume Optimization B: Red Frequent CVP assessments with Fluid Bolus C: Yellow Just observe D: Green If hypotensive start a pressor

55. Once Fluid Given Prior to Fluid After Fluid Infused 15 Min later SCVO265 70
SVV 17
<10%
CVP 5 8
Urine Output
<0.5mL/kg/hr
Better but still  CO
2.6 SV 50 85
SVR
550
MAP

56. What should we do next?
A: Blue We had a 10% or greater increase in SV so now we should give more fluid to see if we still have a response B: Red Start a Pressor Immediately C: Yellow Just observe D: Green Give an dilator to reduce afterload

57. Once Fluid Given Prior to Fluid After Fluid Infused 15 Min later
SCVO2 65 70 72
SVV 17
<10% 4
CVP 5 8 14
Urine Output
<0.5mL/kg/hr
Better but still 
0.5mL/kg/hr CO
2.6
5.2 SV 50 85 86
SVR
550
540
MAP 48

58. What is the Patient Issue?
A: Blue Volume Issue (Think Preload) B: Red Pump Issue (Think Contractility) C: Yellow Squeeze Issue (Think Afterload) D: Green None of the Above – lets talk about another option

59. What intervention should occur?
A: Blue Give more Volume B: Red Start a Pressor C: Yellow Start an inotrope D: Green Start a Dilator

60. Once Pressor Started Great Job!!! You fixed your Pt!! HR 100 CO 6.0
SVV <13%
B/P 110/80 MAP 90
CVP 8
SVR 1092
Great Job!!! You fixed your Pt!!

61. Pt A presents with N and V for 2 days.
SVV 25%
CVP 3
U/O 0.25mL/kg/hr SV
SVI 20
CO 3.0
SVR 950
SVRI 2000

62. What is the Patient Issue?
A: Blue Volume Issue (Think Preload) B: Red Pump Issue (Think Contractility) C: Yellow Squeeze Issue (Think Afterload) D: Green None of the Above – lets talk about another option

63. Scenarios Pt A presents with N and V x 2 days. Parameters
Fluid Started
0900
0915
0930
0945
SVV
25%
20%
15%
10%
CVP 3 6 9 12
U/O
0.25mL/kg
/hr SV 45 50 55 60
SVI 20 25 30 33
SVR
950
955
SVRI
2000
2010 CI 2
2.2
2.5
2.7

64. Scenarios Pt complains of chest pain. Has history of heart failure
SVV 4
CVP 20
U/O >0.5 mL/kg/hr
CO and CI borderline low
SV and SVI is low
SVR & SVRI is Normal

65. What is the Patient Issue?
A: Blue Volume Issue (Think Preload) B: Red Pump Issue (Think Contractility) C: Yellow Squeeze Issue (Think Afterload) D: Green None of the Above – lets talk about another option

66. Scenarios
Pt is post resuscitation from septic shock. Pts MAP is normal.
SVV 9
CVP 12
CO and CI is normal
SV and SVI is normal
SVR & SVRI Low
What do you think could benefit this patient?

67. What is the Patient Issue?
A: Blue Volume Issue (Think Preload) B: Red Pump Issue (Think Contractility) C: Yellow Squeeze Issue (Think Afterload) D: Green None of the Above – lets talk about another option

68. Scenarios Pt arrives and B/P is 210/110. Pt has SVV 8
CO and CI is normal
SV and SVI is normal
SVR & SVRI is high
What do you think could benefit this patient?

69. What is the Patient Issue?
A: Blue Volume Issue (Think Preload) B: Red Pump Issue (Think Contractility) C: Yellow Squeeze Issue (Think Afterload) D: Green None of the Above – lets talk about another option

70. Scenario
Elderly Patient with Septic Shock presented with Fever and Cough. On X ray – pneumonia. Pt hypotensive after fluid bolus and had a Positive screen for sepsis so stat lactic acid was obtained and this was 4.3.
Hemodynamic Numbers are Available

71. Hemodynamic Parameter Hemodynamic Value
SCVO2 49 CO
2.7 CI
1.8 SV 22
SVI 15
SVR
948
SVRI
1422 71

73. Hemodynamic Parameter Hemodynamic Value
Scvo2 49 CO
2.7 CI
1.8 SV 22
SVI 15
SVR
948
SVRI
1422
Elderly patient with sepsis… top is basic V/S monitor then added in Vigileo with ScvO2 73

74. Scenario
Gave Fluids – started 30mL/Kg 1 liter
infused

75. Hemodynamic Parameter Hemodynamic Value
Scvo2 59 CO
3.9 CI
2.6 SV 41
SVI 27
SVR
1374
SVRI
2061
After fluid (1 liter) 75

76. Scenario
Are we to goal yet?

77. Hemodynamic Parameter Hemodynamic Value
Scvo2 66 CO
4.5 CI
3.0 SV 51
SVI 34
SVR
1333
SVRI
2000
After second liter of fluid 77

78. Scenario
Are we to goal yet?
What might we consider?

79. Hemodynamic Parameter Hemodynamic Value
Scvo2 72 CO
5.8 CI
3.9 SV 68
SVI 45
SVR
1089
SVRI
1634 79

80. Questions

81. Angela Craig APN,MS,CCNS
Thank You!
Angela Craig APN,MS,CCNS