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Inferior Vena Cava Guided Fluid Resuscitation

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Inferior Vena Cava Guided Fluid Resuscitation

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Mayo Clinic Critical Care Grand Rounds (26 Feb 2015)
Pro-Con debate: The use of ultrasound assessment of the Inferior Vena Cava to guide fluid resuscitation: fact or fiction?
Anaesthesia-Critical Care.

Mayo Clinic Critical Care Grand Rounds (26 Feb 2015)
Pro-Con debate: The use of ultrasound assessment of the Inferior Vena Cava to guide fluid resuscitation: fact or fiction?
Anaesthesia-Critical Care.

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Inferior Vena Cava Guided Fluid Resuscitation

  1. 1. ©2015 MFMER | slide-1 Inferior Vena Cava Guided Fluid Resuscitation Pro – Con Debate William ‘Brian’ Beam – Hon Liang Tan Critical Care Grand Round 26 Feb 2015
  2. 2. ©2015 MFMER | slide-2  Have responded with nothing to disclose. William (Brian) Beam, MD Hon Liang Tan, MBBS Critical Care Grand Rounds Disclosure Summary
  3. 3. ©2015 MFMER | slide-3  Planning committee members who have nothing to disclose: Richard A. Oeckler, MD, PhD, Co-Director Juan N. Pulido, MD, Co-Director Kim Jones, Program Coordinator Disclosure Summary As a provider accredited by ACCME, Mayo Clinic College of Medicine (Mayo School of CPD) must ensure balance, independence, objectivity and scientific rigor in its educational activities. Course Director(s), Planning Committee Members, Faculty, and all others who are in a position to control the content of this educational activity are required to disclose all relevant financial relationships with any commercial interest related to the subject matter of the educational activity. Safeguards against commercial bias have been put in place. Faculty also will disclose any off label and/or investigational use of pharmaceuticals or instruments discussed in their presentation. Disclosure of this information will be published in course materials so those participants in the activity may formulate their own judgments regarding the presentation. Critical Care Grand Rounds Disclosure Summary Continued
  4. 4. ©2015 MFMER | slide-4 Learning Objectives • Interpret ultrasound findings of the inferior vena cava in critically ill patients. • Translate ultrasound findings of the inferior vena cava to clinical management of critically ill patients. • Identify the limitations of using ultrasound guided fluid resuscitation.
  5. 5. ©2015 MFMER | slide-5 Introduction • Care of the critically ill patient involves: • Rapid diagnosis • Targeted treatment of underlying pathology while • Supporting organ function and • Avoiding iatrogenic harm
  6. 6. ©2015 MFMER | slide-6 Introduction • A Major Tenet of Critical Care: • Optimization of cardiovascular function: • Vasopressive/inotropic medication • Mechanical ventilation • Hemoglobin/oxygen carrying capacity of blood • Fluid intervention/resuscitation
  7. 7. ©2015 MFMER | slide-7 Introduction • Increased use of ultrasound in the Intensive Care Unit (ICU) • Technological advances • Greater affordability • Safe • Rapid • Non-invasive • Repeatable
  8. 8. ©2015 MFMER | slide-8 Introduction • Inferior Vena Cava Guided Fluid Resuscitation • Many investigators/publications • Various IVC US parameters demonstrated • But conclusions are conflicting and medical opinions are not unanimous.
  9. 9. ©2015 MFMER | slide-9 Introduction • In this Pro – Con Debate, we aim to • Enhance your understanding of the US derived IVC parameters • Explore the controversies of this modality in the care of the critically ill • Enable you to arrive at YOUR conclusions for YOUR practice.
  10. 10. ©2015 MFMER | slide-10 Assessment of the Inferior Vena Cava using ultrasound is useful in guiding fluid resuscitation. A. Yes B. No A. B. 0%0%
  11. 11. ©2015 MFMER | slide-11 Intensivists should routinely use ultrasound assessment of the IVC to guide fluid resuscitation in critically ill patients. A. Yes B. No A. B. 0%0%
  12. 12. ©2015 MFMER | slide-12 Inferior Vena Cava Guided Fluid Resuscitation PRO Brian Beam
  13. 13. ©2015 MFMER | slide-13 Premise #1 • Determining the intravascular volume status of critically ill patients is DIFFICULT • And not something we always do well
  14. 14. ©2015 MFMER | slide-14 Dry, Wet or Just Right Hypovolemia Hypervolemia Optimal Tissue Perfusion Chinn (Producer) & Marsh (Director). (2008). Man on Wire [Motion Picture]. USA: Magnolia.
  15. 15. ©2015 MFMER | slide-15 http://www.express.co.uk/news/weird/164768/Tightrope-walker-trips-1-600ft-in-the-air Mohsenin. J of Critical Care (2015) Epub ahead of Print.
  16. 16. ©2015 MFMER | slide-16 Dry, Wet or Just Right Chinn (Producer) & Marsh (Director). (2008). Man on Wire [Motion Picture]. USA: Magnolia http://www.express.co.uk/news/weird/164768/Tightrope-walker- trips-1-600ft-in-the-air
  17. 17. ©2015 MFMER | slide-17 Determining Volume Status: Tools of the Trade Risk -Potential for Harm Benefit -Diagnostic Yield • History • Exam • Non-Invasive monitors • Labs • Ultrasound • Invasive monitors
  18. 18. ©2015 MFMER | slide-18 Premise #2 • We must thoroughly understand the diagnostic tools we plan to utilize. • If we don’t then we as providers WILL make errors in therapeutic decision making JAMA 1990; 264:2928-32.
  19. 19. ©2015 MFMER | slide-19 Premise #3 • The best clinicians make decisions after synthesizing the entire clinical picture!
  20. 20. ©2015 MFMER | slide-20 Premise #4 • Ultrasound is a tool that holds tremendous potential to assist in clinical decision making in critically ill patients. http://www.intropsych.com/ch07_cognition/learning_curve.html
  21. 21. ©2015 MFMER | slide-21 Focused Transthoracic Ultrasound European Journal of Anaesthesiology 2004; 21: 700-707)
  22. 22. ©2015 MFMER | slide-22European Journal of Anaesthesiology 2004; 21: 700-707)
  23. 23. ©2015 MFMER | slide-23 Premise #5 • “Static” measurements which attempt to infer intravascular volume status are generally poor predictors of intravascular volume Shippey. Critical Care Med. 1984. Vol 12. No 2.
  24. 24. ©2015 MFMER | slide-24 Premise #5 • “Static” measurements which attempt to infer intravascular volume status are generally poor predictors of intravascular volume • *Except maybe at the extremes* Shippey. Critical Care Med. 1984. Vol 12. No 2.
  25. 25. ©2015 MFMER | slide-25 Static Measurement of IVC • Cadaveric Study of 69 Livers • Examined retrohepatic segment of IVC • Median Diameter of IVC was 2.3 cm (range 1.5 to 8.2 cm) Indian J Gastroenterol 2009(November–December):28(6):216–220 Image from: http://thesocietypages.org/socimages/2014/07/page/3/
  26. 26. ©2015 MFMER | slide-26 Premise #6 • Dynamic indices of intravascular volume are more helpful in guiding fluid administration Pulse Pressure Variation Dynamic Changes of IVC diameter Dynamic changes in aortic flow velocity/stroke volume assessed by Doppler methods End-expiratory occlusion test Dynamic changes of the plethysmographic waveform Passive leg raising
  27. 27. ©2015 MFMER | slide-27 Ultrasound of the IVC Images from: https://web.stanford.edu/group/ccm_echocardio/cgi-bin/mediawiki/index.php/IVC http://echocardiographer.org/TTE.html
  28. 28. ©2015 MFMER | slide-28 Dynamic Changes in IVC Diameter: The Physiology Utilizes the interplay between the compliance of the IVC and cyclical changes in intra-thoracic pressure during the respiratory cycle
  29. 29. ©2015 MFMER | slide-29 Dynamic Changes in IVC Diameter: The Physiology Images from: https://web.stanford.edu/group/ccm_echocardio/cgi- bin/mediawiki/index.php/IVC
  30. 30. ©2015 MFMER | slide-30 Dynamic Changes in IVC Diameter: The Physiology Image from: https://web.stanford.edu/group/ccm_echocardio/cgi- bin/mediawiki/index.php/IVC
  31. 31. ©2015 MFMER | slide-31 Dynamic Changes in IVC Diameter: The Physiology Abdomen Thorax
  32. 32. ©2015 MFMER | slide-32 Dynamic Changes in IVC Diameter: The Physiology Bodson and Vieillard-Baron Critical Care 2012, 16:181 Unfortunately, the Devil is in the Details Spontaneous Mechanical Ventilation • Normal • Increased Intra-Ab Pressure
  33. 33. ©2015 MFMER | slide-33 Dynamic Changes in IVC Diameter • The IDEAL STUDY • Enrolls critically ill patients with hemodynamic instability and uncertainty regarding intravascular volume status • Accurately performs measurement of dynamic change in IVC diameter • Accurately measures change in stroke volume after fluid challenge
  34. 34. ©2015 MFMER | slide-34 Spontaneously Breathing Patients- Corl • 30 spontaneously breathing ED patients suspected to be hypovolemic • No correlation between fluid responsiveness and IVC Index Emergency Medicine Australasia (2012) 24, 534–539
  35. 35. ©2015 MFMER | slide-35 Spontaneously Breathing Patients- Muller • 40 spontaneously breathing ICU pts with circulatory failure • Measured IVC 2-3 cm from the right atrium • Responsiveness: 15% increase in subaortic velocity time index (VTI) after 500 mL Hetastarch bolus • cIVC = (Dmax-Dmin)/Dmax x 100 • Cutoff: cIVC 40% • PPV 72% • NPV 83% Critical Care 2012, 16:R188
  36. 36. ©2015 MFMER | slide-36 Spontaneously Breathing Patients- Lanspa • 14 spontaneously breathing ICU patients with early sepsis • Measured IVC prox to hepatic veins (0.5-3 cm from RA junction) • Volume Responsiveness: >15% increase CI after 10 ml/kg bolus • cIVC= (Dmax-Dmin)/Dmax x 100 • Cutoff: cIVC 15% • PPV 62% • NPV 100% Shock. 2013 Feb;39(2):155-60
  37. 37. ©2015 MFMER | slide-37 Spontaneously Breathing Patients- Conclusion • cIVC >40% - Fluid responsive- maybe • cIVC <15% - NOT fluid responsive cIVC= (Dmax-Dmin)/Dmax x 100
  38. 38. ©2015 MFMER | slide-38 Mechanically Ventilated Patients- Moretti • 29 patients with SAH. Intubated, sedated, paralyzed. MV, TV= 8 mL/kg • IVC measured 2 cm caudal from suprahepatic vein • Responsiveness: 15% increase in CI after 7 ml/kg Hetastarch bolus • dIVC= (Dmax-Dmin)/Dmin x 100 • Cutoff: dIVC 16% • PPV 70.5% • NPV 100% Neurocrit Care (2010) 13:3-9
  39. 39. ©2015 MFMER | slide-39 Mechanically Ventilated Patients- Barbier • 20 patients with severe sepsis. MV, TV 8.5 ml/kg, PEEP 4 • IVC measured upstream from suprahepatic vein • Volume Responsiveness: 15% increase in CO after 7 ml/kg plasma expander • dIVC= (Dmax-Dmin)/Dmin x 100 • Cutoff: dIVC 18% • PPV 90% • NPV 90% Intensive Care Med (2004) 30:1740–1746
  40. 40. ©2015 MFMER | slide-40 Mechanically Ventilated Patients- Feissel • 39 patients in septic shock. MV, TV 8-10 mL/kg • IVC measured 3 cm from RA • Volume Responsiveness: 15% increase in CO after 8 ml/kg Hetastarch bolus • ∆IVC= (Dmax-Dmin)/[(Dmax + Dmin)/2] x 100 • Cutoff: ∆IVC 12% • PPV 93% • NPV 92% Intensive Care Med (2004) 30:1834–1837
  41. 41. ©2015 MFMER | slide-41 Mechanically Ventilated Patients: Conclusion • In hemodynamically unstable patients who are mechanically ventilated without spontaneous respiratory effort and TV ≥8 ml/kg • dIVC >18% - fluid responsive • dIVC <16% - NOT fluid responsive • What about ∆IVC cutoff of 12%? dIVC= (Dmax-Dmin)/Dmin x 100 ∆IVC= (Dmax-Dmin)/[(Dmax + Dmin)/2] x 100
  42. 42. ©2015 MFMER | slide-42 Mechanically Ventilated Patients: Simplified Conclusion • In hemodynamically unstable patients who are mechanically ventilated without spontaneous respiratory effort and TV ≥8 ml/kg • dIVC >20% - likely fluid responsive • dIVC <10% - likely NOT fluid responsive dIVC= (Dmax-Dmin)/Dmin x 100
  43. 43. ©2015 MFMER | slide-43 Conclusion • Determining optimal intravascular volume status of ICU patients is difficult • Evaluation of the dynamic changes of the IVC with respiration is a low risk and readily available tool that can provide useful information in the appropriate clinical settings
  44. 44. ©2015 MFMER | slide-44 Image from: http://jeffreyhill.typepad.com/english/2010/10/cartoon-throwing-the-baby-out-with-the- bathwater.html Limitations IVC US
  45. 45. ©2015 MFMER | slide-46 Inferior Vena Cava Guided Fluid Resuscitation CON Hon Liang Tan
  46. 46. ©2015 MFMER | slide-47 Setting boundaries • I submit: • An extremely small/flat IVC or high IVC-CI likely indicates hypovolemia in the correct clinical context. • An extremely large IVC or low IVC-CI is likely to indicate hypervolemia in the correct clinical context.
  47. 47. ©2015 MFMER | slide-48 Setting boundaries • But: • "Correct clinical context" may be obvious to the experienced clinician
  48. 48. ©2015 MFMER | slide-49 Defining the Case • Thus, • What we want to know is if it is useful in grey zones / difficult cases. • Limited/no value for difficult cases. • In the hands of an inexperienced, it might even be dangerous weapon.
  49. 49. ©2015 MFMER | slide-50 Inferior Vena Cava Guided Fluid Resuscitation - Con • What is the logic? • What’s wrong with the logic? • Why is the evidence contradictory? • So why bother?
  50. 50. ©2015 MFMER | slide-51 What is the logic? • The logic: • IVC connected to right atrium • Compliant IVC • Distention = intra-luminal pressure = right atrium pressure
  51. 51. ©2015 MFMER | slide-52 What is the logic? • Correlation demonstrated. Or was it? • 83 patients: US assessment followed by “floatation catheter” within 24 hours. • RA pressure (range 0 to 28 mm Hg) IVC Characteristic Correlation Coefficient Expiratory Diameter 0.48 Inspiratory Diameter 0.71 Percentage Collapse 0.75
  52. 52. ©2015 MFMER | slide-53 What is the logic? • Percentage Collapse: • Discrimination of RA pressure > 10 mm Hg maximized at 50% level of collapse. • Wonderful! • Or it is?
  53. 53. ©2015 MFMER | slide-54 What’s wrong with the logic? • It does not account for: • Patient characteristics • Intra-luminal factors • Extra-luminal factors • Operator/technical factors • Problems with measurement
  54. 54. ©2015 MFMER | slide-55 What’s wrong with the logic? • Patient characteristics • Patient POSITION • American Society of Echocardiography (ASE) • Left lateral decubitus
  55. 55. ©2015 MFMER | slide-56 What’s wrong with the logic? • In ICU, what do we do? • Supine, head up 30 degrees! • IVC changes shape in different positions. • IVC larger in supine than in left lateral.
  56. 56. ©2015 MFMER | slide-57 What’s wrong with the logic? • Patient characteristics • Changes of the IVC with AGE • 200 patients : 17 to 94 years old. • Age • Inversely correlated with IVC diameter. • Proportionally increases IVC-CI.
  57. 57. ©2015 MFMER | slide-58 What’s wrong with the logic? • Patient characteristics • ETHNICITY/PHYSIQUE of patients (Asian) • IVC > 19mm = RAP >10mmHg (sensitivity, 75%; specificity, 78%) • IVC-CI > 30% (sensitivity, 75%; specificity, 83%).
  58. 58. ©2015 MFMER | slide-59 What’s wrong with the logic? • Patient characteristics • LIVER DISEASE Max IVC Diameter (cm) IVC Reduction (cm) Sniff Normal 2.35 +/- 0.34 1.30 +/- 0.67 Cirrhotic 1.74 +/- 0.35 0.03 +/- 0.09
  59. 59. ©2015 MFMER | slide-60 What’s wrong with the logic? • Intra-luminal factors • Right ventricular compliance • Tricuspid valve disease • Obstruction distal to right atrium • Blood flow diversion
  60. 60. ©2015 MFMER | slide-61 What’s wrong with the logic? • Intra-luminal factors • RV COMPLIANCE/DIASTOLIC FAILURE • Close correlation between LV and RV diastolic parameters.
  61. 61. ©2015 MFMER | slide-62 What’s wrong with the logic? • Intra-luminal factors • RV COMPLIANCE/DIASTOLIC FAILURE • > 1/3 have LV diastolic dysfunction on admission. • >1/3 develop reversible diastolic dysfunction at least once during admission.
  62. 62. ©2015 MFMER | slide-63 What’s wrong with the logic? • Intra-luminal factors • TRICUSPID VALVE DISEASE • Tricuspid Regurgitation/Stenosis • OBSTRUCTION DISTAL TO RIGHT ATRIUM • Pulmonary valve disease • Pulmonary Hypertension • Numerous causes • Tumor
  63. 63. ©2015 MFMER | slide-64 What’s wrong with the logic? • Intra-luminal factors • BLOOD FLOW DIVERSION • Pathological states – portosystemic shunts • Relationship between IVC parameters and volume status in such situations has not been validated
  64. 64. ©2015 MFMER | slide-65 What’s wrong with the logic? • Extra-luminal factors • Intra-thoracic pressure • Spontaneous vs mechanical ventilation • Intra-pericardial pressure • Intra-abdominal pressure
  65. 65. ©2015 MFMER | slide-66 What’s wrong with the logic? • Extra-luminal factors • INTRA-PERICARDIAL PRESSURE • Cardiac tamponade • INTRA-THORACIC PRESSURE • Tension pneumothorax • Spontaneous vs mechanical ventilation
  66. 66. ©2015 MFMER | slide-67 What’s wrong with the logic? • Extra-luminal factors • INTRA-THORACIC PRESSURE • Spontaneous ventilation • Respiratory pattern • Abdominal/diaphragmatic breathing resulted in greater IVC-CI compared to thoracic breathing
  67. 67. ©2015 MFMER | slide-68 What’s wrong with the logic? • Extra-luminal factors • INTRA-THORACIC PRESSURE • Spontaneous ventilation • "Sniff Test” • Unable to standardize patient effort • Respiratory distress • Tidal volume •
  68. 68. ©2015 MFMER | slide-69 What’s wrong with the logic? • Extra-luminal factors • INTRA-THORACIC PRESSURE • Mechanical ventilation • Paralysis? Mode? • Chest wall / lung compliance? • Tidal volume (8-10 ml/kg) / PEEP? 12% 18%
  69. 69. ©2015 MFMER | slide-70 What’s wrong with the logic? • Extra-luminal factors • INTRA-ABDOMINAL PRESSURE • Intra-Abdominal Hypertension • 32-56% • Abdominal Compartment Syndrome • 2-10% • Conversely, open abdomen?
  70. 70. ©2015 MFMER | slide-71 What’s wrong with the logic? • Operator/technical factors • Technical difficulties in assessing the IVC • Potential error in measurement • Inter-operator variability • Site of measurement
  71. 71. ©2015 MFMER | slide-72 What’s wrong with the logic? • Operator/technical factors • TECHNICAL DIFFICULTIES • Impossible in up to 18% of patients
  72. 72. ©2015 MFMER | slide-73 What’s wrong with the logic? • Operator/technical factors • TECHNICAL DIFFICULTIES • IVC moves • Vertically by 21.9 mm • Horizontally by 3.9 mm • M mode not measuring same point.
  73. 73. ©2015 MFMER | slide-74 What’s wrong with the logic? • Operator/technical factors • ERRORS IN MEASUREMENT • Foreshorten views
  74. 74. ©2015 MFMER | slide-75 What’s wrong with the logic? • Operator/technical factors • ERRORS IN MEASUREMENT • IVC-CI = Max diameter – Min Diameter Max Diameter • Small error (in mm) results in large changes
  75. 75. ©2015 MFMER | slide-76 Spontaneous Breathing Patient cIVC= (Dmax-Dmin)/Dmax x 100 cIVC >40% - Fluid responsive cIVC ≤15% - NOT fluid responsive Mechanically Ventilated patient, no respiratory effort, TV 8-10 mL/kg dIVC= (Dmax-Dmin)/Dmin x 100 dIVC >18% - fluid responsive dIVC <16% - NOT fluid responsive ∆IVC= (Dmax-Dmin)/[(Dmax + Dmin)/2] x 100 ∆IVC >12% - fluid responsive ∆IVC <12%- NOT fluid responsive
  76. 76. ©2015 MFMER | slide-77 What’s wrong with the logic? • Operator/technical factors • SITE OF MEASUREMENT • IVC collapses unequally
  77. 77. ©2015 MFMER | slide-78 What’s wrong with the logic? • Operator/technical factors • SITE OF MEASUREMENT • IVC collapses unequally • Different site of measurement = different dimensions • Long axis view from lateral trans- hepatic window may make the IVC appear to collapse less
  78. 78. ©2015 MFMER | slide-79 What’s wrong with the logic? • Operator/technical factors • SITE OF MEASUREMENT • No consensus of where to measure. • ASE: 0.5 – 3 cm from right atrium.
  79. 79. ©2015 MFMER | slide-80 What’s wrong with the logic? • Operator/technical factors • INTER-OPERATOR VARIBILITY • Inter-operator agreement among trained ED physicians is moderate.
  80. 80. ©2015 MFMER | slide-81 Why is the evidence contradictory? • Studies do not uniformly account for: • Patient characteristics • Intra-luminal factors • Extra-luminal factors • Operator/technical factors
  81. 81. ©2015 MFMER | slide-82 So why bother? • Multiple confounders/factors affect IVC parameters • Purported IVC parameters cut offs overlap significantly • Exact values cannot be established with certainty • Can lead to erroneous conclusions • No evidence to show better outcomes
  82. 82. ©2015 MFMER | slide-83 So why bother? • Even if RAP = CVP • So what??
  83. 83. ©2015 MFMER | slide-84 Conclusion • Ultrasound assessment of IVC is NOT useful in guiding fluid resuscitation when it matters most. • Routine assessment of IVC in the critically ill patient is NOT necessarily diagnostic or warranted.
  84. 84. ©2015 MFMER | slide-85 Post Debate Evaluation *High stakes*
  85. 85. ©2015 MFMER | slide-86 Assessment of the Inferior Vena Cava using ultrasound is useful in guiding fluid resuscitation. A. Yes B. No A. B. 0%0%
  86. 86. ©2015 MFMER | slide-87 Intensivists should routinely use ultrasound assessment of the IVC to guide fluid resuscitation in critically ill patients. A. Yes B. No A. B. 0%0%
  87. 87. ©2015 MFMER | slide-88 Questions & Discussion Tan.Honliang@mayo.edu Beam.William@mayo.edu

Editor's Notes

  • Man on Wire– Phillippe Petit
    1974 high-wire walk between the Twin Towers of New York's World Trade Center

    Pole is used to increase rotational inertia and lower the center of gravity

    Will carry metaphor further.
    Balance between:
    uncorrected hypovolemia leads to inappropriate vasopressor use, increased organ hypoperfusion/ischemia, increased mortality
    Hypervolemia increased complications, ICU stay, and mortality

    Uncorrected hypovolemia-> leading to inappropriate infusions of vasopressor agents->increase organ hypoperfusion and ischemia [4].
    Overzealous fluid resuscitation has been associated with increased complications, increased length of intensive care unit (ICU) and hospital stay, and increased mortality. A review of the ARDSNet cohort demonstrated a clear positive association between the mean cumulative daily fluid balance and mortality [5].
    Murphy and colleagues demonstrated a similar finding in patients with septic shock [6]. Data from the “Vasopressin in Septic Shock Trial” demonstrated that the quartile of patients with the highest fluid balance at both 12 hours and 4 days had the highest adjusted mortality [7].
  • http://gasexchange.com/questions/is-cvp-actually-a-useful-parameter-to-monitor-during-anaesthesia/

    Assessment of preload and fluid responsiveness in intensive care unit.
    How good are we? Mohsenin. J of Critical Care
  • Tools of the trade
  • History
    Physical examination
    -Cap refill
    Skin perfusion
    - Cap refill
    Mentation
    Cold extremities

    Monitors
    -Noninvasive– EKG, SpO2, NIBP, Urinary catheter, Skeletal muscle tissue oxygenation (StO2), tissue pCO2, Ultrasound
    -Invasive– Art lines, CVP, FloTrac, TEE, TE Doppler, PA Catheters

    Labs
    Lactate, VBG, SVO2, ABG
  • Story of the Swan Ganz Catheter– Iberti et al– 1990– average score of 67%--- practicing physicians understanding of use and interpretation of SGC
  • No one test is perfect--- we need to use our heads
  • F-TTE
    Is the left ventricular (LV) function normal?
    Is the right ventricular (RV) function normal?
    Is there a pericardial effusion?
    What is the volume status of the patient?

    Assessment for pericardial effusion
    Evaluation of relative chamber size
    Global cardiac function
    Patient volume status- left ventricular (LV) size, ventricular function, and inferior vena cava (IVC) size
    and respiratory change.
  • Shippey. Critical Care Med. 1984. Vol 12. No 2.
    125I labeled albumin to measure total lung volume
    Blood volume and hemodynamic variables measured after resuscitation during quiescent period
    Mean +/- SE of values for the study

    --- A great deal of effort has been invested into attempting to correlate CVP and IVC diameter
    --- CVP isn’t really a reliable indicator thus any attempts to correlate with IVC diameter doesn’t really matter to me when making decisions regarding volume status in the ICU
  • CVP < 5 or >12 may be predictive of low or high blood volume
  • From subcostal 4 chamber view, translate the probe medially to visualize the right atrium on the right of the screen, and to see a large part of the liver: keep the same depth and direction, translate the tip of the probe toward the right shoulder.
    Then rotate the probe counter-clockwise until you see the long axis of the IVC merging into the right atrium.
    You will see the IVC passing through the liver and merging with the right atrium. Often, you can visualize the sub-hepatic veins merging in the IVC
  • Increased Intra-Ab or Intra-Thoracic P will lead to alterations in IVC diameter/distensibility
    Changes in RA: RV dysfunction, TR, pericardial effusion, arrythmias….
  • ACF was defined as mean arterial pressure (MAP) < 65 mmHg, urine output < 0.5 mL/Kg/h, tachycardia, mottled skin and/or biological
    signs of hypoperfusion (arterial blood lactate > 2 mmol/L).
  • cIVC– respiratory variation of IVC

    ACF was defined as mean arterial pressure (MAP) < 65 mmHg, urine output
    < 0.5 mL/Kg/h, tachycardia, mottled skin and/or biological
    signs of hypoperfusion (arterial blood lactate > 2 mmol/L). The AUC of the ROC curve for cIVC was 0.77
  • (VCCI ≥ 15% had poor positive
    predictive value (PPV, 62%), but excellent negative predictive value (NPV, 100%, p = 0.03,
    Table 3). A threshold for VCCI ≥ 50% had fair positive (75%) and good negative (80%)
    predictive value, although did not achieve statistical significance (p = 0.09).
  • d IVC- distensibility index of IVC

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