Fluid Resuscitation And Massive Transfusion


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  • Transcellular includes pleural, peritoneal, aqueous humor, sweat, urine, lymph and csf
  • i.e. NS 20 % is intravascular vs pentaspan 75-80% intravascular hence the volumes given
  • Outcomes were death, number of organ systems failures, time in ICU/hospital, times on mechanical ventilation and days of dialysis Finally, at least for critically ill patients, with the publication of the Saline versus Albumin Evaluation (SAFE) study, we have conclusive evidence that in the short-term albumin is at least as safe as saline for resuscitation [ 14 ]. This large, randomized clinical trial included a heterogeneous population of nearly 7000 critically ill patients requiring intravascular fluid resuscitation. The Australian and New Zealand Intensive Care Society Clinical Trials Group set out to determine the safety of fluid resuscitation with 0.9% normal saline versus 4% human albumin on a number of patient outcomes. There were no significant differences between the groups with respect to 28-day mortality, incidence of organ failure, intensive care unit or hospital length of stay, or duration of mechanical ventilation or renal replacement therapy. These results were achieved in the albumin arm with significantly less fluid administration, in a ratio of 1:1.4 (albumin versus normal saline) over the first 4 days. However, various subgroup analyses did reveal interesting results. There was a trend towards decreased mortality in septic shock patients treated with albumin (relative risk for death, 0.87; 95% CI, 0.74–1.02). Increased mortality in trauma patients (relative risk, 1.36; 95% CI, 0.99–1.86), especially those with traumatic brain injury (relative risk, 1.62; 95% CI, 1.12–2.34), was observed in the albumin treatment group. There was no overall benefit associated with albumin use in the SAFE trial, although albumin use in septic shock patients may confer a survival advantage. Despite this interesting trend, it is worth noting that recent guidelines from the Surviving Sepsis Campaign and numerous professional critical care organizations advocate the equivalence of initial fluid resuscitation with either crystalloids or colloids (natural or artificial) in septic patients [ 15 ]. The biologic plausibility of improved outcome with albumin in sepsis has been examined in various in vitro and animal models, but the physiologic basis of this effect in vivo is not known [ 2 ]. The increased risk of mortality among trauma patients in the SAFE trial confirms a similar finding from a previous systematic review, where trauma patients who received crystalloids had a lower mortality rate than those who received colloids [ 13 ]. Interpretation of results from subgroup analyses requires caution and confirmation from properly designed clinical trials.
  • Calcium in LR and magnesium in normosol
  • Hypocalcemia from dilution, binding to citrate and hypomagnesemia from dilution
  • ACUTE FEBRILE HEMOLYTIC: The classic presenting triad of fever, flank pain, and red or brown urine (ie, hemoglobinuria) is rarely seen. Fever and chills may be the only manifestations and, in patients under anesthesia or in coma, DIC may be the presenting mode, with oozing of blood from puncture sites and hemoglobinuria.
  • i.e. decreased natural killer cell activity, decreased monocyte activity, decreased B cell stimulation, Overload of RES,
  • Sequential Organ Failure Assessment (SOFA) score
  • Fluid Resuscitation And Massive Transfusion

    1. 1. Fluid Resuscitation and Massive Transfusion Dalhousie Critical Care Lecture Series
    2. 2. Outline <ul><li>Kinetics of fluid therapy </li></ul><ul><li>Colloids vs Crystalloids </li></ul><ul><li>What do we use? </li></ul><ul><ul><li>Sepsis </li></ul></ul><ul><ul><li>Trauma </li></ul></ul><ul><ul><li>Peri-operative </li></ul></ul><ul><li>Massive Transfusion </li></ul><ul><li>Complications of Resuscitation </li></ul><ul><li>Case Examples </li></ul>
    3. 3. Physiology <ul><li>Total body water = 60% of body weight </li></ul><ul><li>In a 70 kg man = 0.6 X 70 = 42L </li></ul><ul><li>Distributed </li></ul><ul><ul><li>Intracellular (425 ml/kg or 2/3) </li></ul></ul><ul><ul><li>Extracellular (175 ml/kg or 1/3) </li></ul></ul>Extracellular Plasma volume Interstitial fluid Transcellular fluid Modified from Miller, 2000
    4. 4. The Extracellular Compartment <ul><li>Divided into the interstitial and the intravascular </li></ul><ul><li>Low pressure in the intravascular is hypotension </li></ul><ul><li>Resuscitation of the intravascular space is what feeds the rest of the compartments </li></ul>Qv = Kf [(Pc – Pi) – δ c( π c – π i)]
    5. 5. What does it mean? <ul><li>Net volume of fluid crossing capillary membrane </li></ul><ul><li>Reflection coefficient = membrane permeability </li></ul><ul><li>Ranges from 0 (completely permeable) to 1 (impermeable) </li></ul><ul><li>What you administer determines distribution </li></ul>from T,J. Gan ASA refresher course 2003
    6. 6. Distribution of Different Fluids
    7. 7. Colloids vs Crystalloids <ul><li>Still no firm data either way </li></ul><ul><li>SAFE study has clarified some questions </li></ul><ul><li>In burns colloids safe as soon as 6 hours </li></ul>
    8. 8. SAFE Study <ul><li>RCT enrolled 6997 patients requiring ICU admit </li></ul><ul><li>Randomized to albumin/NS </li></ul><ul><li>Outcomes at 28 days similar </li></ul><ul><li>But trend toward ↑ mortality in albumin/head trauma </li></ul><ul><ul><li>460 patients </li></ul></ul><ul><ul><li>Mortality higher in albumin group 33.2% vs. 20.4 saline group </li></ul></ul><ul><ul><li>Saline or Albumin for Fluid Resuscitation in Patients with Traumatic Brain InjuryN Engl J Med 2007;357:874-84. </li></ul></ul><ul><li>And  mortality with albumin/septic shock </li></ul><ul><ul><li>N= 1218 patients </li></ul></ul><ul><ul><li>Relative risk of death reduced in albumin group 0.87 p=0.06 </li></ul></ul>SAFE study investigators NEJM 2004;350:2247-2256 .
    9. 9. Crystalloids <ul><li>Balanced = electrolyte solution similar to ECF and contains buffer </li></ul><ul><li>Example = LR or Normosol R </li></ul><ul><li>Separate category = NS </li></ul>
    10. 10. What’s in this stuff? <ul><li>Ringers lactate </li></ul><ul><li>Normal Saline </li></ul><ul><li>Pentaspan </li></ul><ul><li>Normosol R </li></ul>
    11. 11. Content LR NS Normosol Pentaspan Na + 130 154 140 154 K + 4.0 0 5.0 0 Cl - 109 154 98 154 pH 6.7 5.7 7.4 5.4 Buffer Lactate - Acetate/gluconate - osmo 273 308 295 326
    12. 12. Timing of Resuscitation <ul><li>A Cochrane review compared early vs delayed resuscitation. </li></ul><ul><li>Increased risk of dying in early group </li></ul><ul><li>Should we keep the BP low in this group? </li></ul><ul><li>Goal-directed therapy see Rivers et al </li></ul>Kwan et al Cochrane Review 2003
    13. 13. Fluid in Sepsis Resuscitation <ul><li>EGDT Strategy When? </li></ul><ul><li>1hr </li></ul><ul><li>6hr EGD </li></ul><ul><li>How Much? </li></ul><ul><ul><li>1.5L more fluid </li></ul></ul><ul><li>Goal directed therapy reduced mortality by 17%! </li></ul>
    14. 14. Crystalloids vs Colloids in Sepsis <ul><li>Both seem to work equally in restoring hemodynamics </li></ul><ul><li>More volume required with crystalloids </li></ul><ul><li>Lower reflection coefficient for colloids and therefore more sustained hemodynamic effect as it tends to stay in the intravascular space </li></ul><ul><li>May “plug the holes” in vascular leak syndrome </li></ul><ul><li>Less interstitial edema </li></ul>
    15. 15. Crystalloids vs Colloids in Sepsis <ul><li>Nothing is free though: </li></ul><ul><ul><li>Colloids are more expensive </li></ul></ul><ul><ul><li>Albumin is a pooled blood product </li></ul></ul><ul><ul><li>May deposit where they are not wanted </li></ul></ul><ul><ul><ul><li>Skin – pruritis </li></ul></ul></ul><ul><ul><ul><li>Kidneys </li></ul></ul></ul><ul><ul><ul><ul><li>osmotic damage to proximal tubules described in multiple settings </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Clinically can be seen as decreased renal function in at risk populations </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Schortgen F, Lacherade JC, Bruneel F, et al:Effects of hydroxyethylstarch and gelatin on renal function in severe sepsis: A multicentre randomised study. Lancet 2001; 357:911–916 </li></ul></ul></ul></ul>
    16. 16. … but no difference in need for renal replacement therapy
    17. 17. Summary of Resuscitation in Sepsis <ul><li>Fluid is good </li></ul><ul><li>Crystalloid resuscitation is safe </li></ul><ul><li>Colloids look good but need a large RCT to prove it </li></ul><ul><li>The role of blood is still unknown </li></ul>
    18. 18. Trauma <ul><li>Conventional wisdom espoused by ATLS is 2L of crystalloids followed by PRBC to restoration of normal heart rate and BP </li></ul><ul><li>Controversies </li></ul><ul><ul><li>Type of crystalloid </li></ul></ul><ul><ul><li>Permissive hypotension </li></ul></ul><ul><ul><li>Hypertonic crystalloids </li></ul></ul><ul><ul><li>Colloids </li></ul></ul>
    19. 19. Class I ClassII Class III Class IV Clinical Correlates of Hemorrhage American College of Surgeons, 1989 Blood loss (mL) > 750 750 - 1500 1500 - 2000 > 2000 Blood loss (% total) > 15% 15 - 30% 30 - 40% > 40% Pulse rate < 100 > 100 > 120 > 140 Blood pressure Normal Normal ↓ ↓ Pulse pressure Normal or ↑ ↓ ↓ ↓ Orthostasis Absent Minimal Marked Marked Capillary refill Normal Delayed Delayed Delayed Resp rate 14 - 20 20 - 30 30 - 40 > 34 UO (mL/hr) > 30 20 - 30 5 - 15 < 5 CNS mental status Slight anxiety Mild anxiety Anxious/confused Confused/lethargic CI (L/min) ↓ 0-10% ↓ 20-50% ↓ 50-75% ↓ >75%
    20. 20. Hypertonic Saline <ul><li>250 mL of 7.5% saline = 2-3 L of 0.9% saline </li></ul><ul><li>Has been evaluated with 8 RCT </li></ul><ul><li>Improved rates of survival in 7, but only statistical significance only achieved in 1 </li></ul><ul><li>Meta-analysis demonstrated improved survival rates, especially in head trauma (38% versus 27%) </li></ul><ul><ul><li>Wade CE, Kramer GC, Grady JJ, et al. Efficacy of hypertonic 7.5% saline and6%dextran-70 in treating trauma: a meta-analysis of controlled clinical studies. Surgery 1997;122:609–16. </li></ul></ul>
    21. 21. Summary of Resuscitation in Trauma <ul><li>In the absence of traumatic brain injury permissive hypotension with BP>80, good pulses and alert patient is reasonable prior to definitive surgical management </li></ul><ul><li>Ringers lactate is the recommended crystalloid </li></ul><ul><li>Hypertonic saline may be the way to go but is not yet the standard of care </li></ul><ul><li>Blood is still the best </li></ul><ul><ul><li>O negative immediately available </li></ul></ul><ul><ul><li>Type specific in ~10 minutes </li></ul></ul><ul><ul><li>Cross and Type ~ 60 minutes </li></ul></ul>
    22. 22. Summary of Resuscitation in Trauma <ul><li>Transfusion of blood components in the setting of hypotension and ongoing bleeding should be empiric and not wait for coagulopathy to develop. Especially in the setting of massive transfusion (~10u PRBC) </li></ul><ul><li>FFP:PRBC should be around 1:1 </li></ul><ul><li>Platlets may be targeted to counts, but are generally needed after 10u PRBC. </li></ul><ul><li>If greater than 6 units of blood have been given with evidence of microvascular bleeding consider coagulation adjuncts such as VIIa. </li></ul>
    23. 23. Peri-op Fluids <ul><li>How much is too much? </li></ul><ul><li>Recent study in Annals of Surgery </li></ul><ul><li>Two groups of patients undergoing colon surgery: </li></ul><ul><ul><li>Third space loss replaced (standard) </li></ul></ul><ul><ul><li>Third space loss not replaced (restricted) </li></ul></ul><ul><li>Group 2 less CV/RESP/Wound complications </li></ul>Brandstrup, B etal Ann Surg 2003; 238:641-648
    24. 24. Peri-op Fluids <ul><li>Review of recent study by Kabon Anesthes. Analg. 2005 showed no reduction in infection with liberal fluid administration. </li></ul><ul><li>Venn in 2002 found vigorous hydration  hospital stay and # of post-op complications in Femur #. </li></ul>
    25. 25. Type and Screen <ul><li>Blood is ABO-Rh typed & screened for common antibodies </li></ul><ul><li>99.8% chance of compatibility for type </li></ul><ul><li>99.94% with antibody screen </li></ul><ul><li>99.95% with crossmatch </li></ul><ul><li>Many institutions do not X-match blood </li></ul><ul><li>Type specific blood available < 10 minutes! </li></ul>
    26. 26. Blood Product Availability <ul><li>6 units type 0 pRBC in ER </li></ul><ul><li>Give Rh- blood to women of reproductive age </li></ul><ul><li>Type specific blood 5 to 10 minutes </li></ul><ul><li>Plasma 45 minutes </li></ul><ul><li>Cryoprecipitate, platelets in 10 minutes </li></ul>
    27. 27. Estimated Blood Volume (EBV) <ul><li>65 to 70 ml/kg </li></ul><ul><li>In 70 kg man total blood volume = 5L </li></ul><ul><li>Remember in 50 kg female </li></ul><ul><li>50 X 0.7 = 3.5L ! </li></ul>
    28. 28. Massive Transfusion <ul><li>No strict definition </li></ul><ul><li>Accepted = transfusion of > 1 blood volume </li></ul><ul><li>Recall our 70 kg patient </li></ul><ul><li>EBV = 5 L lost or 10-12 units pRBC transfused </li></ul>
    29. 29. Blood Component Therapy <ul><li>Whole blood is not available in Canada except Autologous Donation </li></ul><ul><li>Options include : </li></ul><ul><ul><li>pRBC </li></ul></ul><ul><ul><li>Plasma </li></ul></ul><ul><ul><li>Cryoprecipitate </li></ul></ul><ul><ul><li>Platelets </li></ul></ul><ul><ul><li>Factor VII a </li></ul></ul>
    30. 30. Packed Cells <ul><li>Hematocrit 0.70 </li></ul><ul><li>Volume = 300 ml </li></ul><ul><li>NS, LR, Normosol, Plasma acceptable diluents </li></ul><ul><li>Stored in CPDA /ADsol at QEII (citrate phosphate dextrose adenine) citrate binds calcium </li></ul><ul><li>All pRBC in Canada leukocyte reduced </li></ul>
    31. 31. Platelets <ul><li>Indicated when platelet count < 75,000 </li></ul><ul><ul><li>SITUATION SPECIFIC…! </li></ul></ul><ul><li>One unit should increase platelet count by 10,000 </li></ul><ul><li>Order: 1 bag=4 “old” units </li></ul><ul><li>Ensure proper filter used for transfusion </li></ul><ul><ul><li>Transfusion time important </li></ul></ul><ul><li>Rarely required < 15 units pRBC …??? </li></ul><ul><li>High risk of TRALI </li></ul>
    32. 32. Thrombocytopenia
    33. 33. Plasma <ul><li>Rich in coagulation factors EXCEPT factor V and VIII WHY? </li></ul><ul><li>Fibrinogen content low in plasma </li></ul><ul><li>Available in 500 ml aliquots </li></ul><ul><ul><li>1L = 4 units  10% increase CF </li></ul></ul><ul><li>30 to 45 minutes to process and thaw </li></ul><ul><li>After 5 units pRBC consider 1:1 plasma and pRBC </li></ul>
    34. 34. Activated factor VII <ul><li>Derived from hamster kidney cell line </li></ul><ul><li>Binds exposed tissue factor </li></ul><ul><ul><li>generates small amt. of thrombin </li></ul></ul><ul><ul><li>activates platelets </li></ul></ul><ul><ul><li>amplifies thrombin production </li></ul></ul><ul><li>Very expensive </li></ul><ul><li>No evidence that improves outcome (too early in use) </li></ul>
    35. 35. Activated Factor VII <ul><li>Good review in Critical Care Medicine 2005 33:883-890 </li></ul><ul><li>Factor VIIa now used in liver disease/Tx, decreases # of packed cells transfused </li></ul><ul><li>Surgery prostatectomy eliminated pRBC in treatment group (60% of placebo were transfused) </li></ul><ul><li>Trauma RCT underway (QEII part of study) </li></ul>
    36. 36. Cryoprecipitate <ul><li>Rich in factor VIII, fibrinogen (I), XIII, vWF </li></ul><ul><li>Comes in “units” usually 8 at a time </li></ul><ul><li>for the replacement of fibrinogen, vWF </li></ul><ul><ul><li>treatment of uremic bleeding in appropriate circumstances, </li></ul></ul><ul><ul><li>treatment and prevention of severe factor XIII deficiency. </li></ul></ul><ul><ul><li>DIC </li></ul></ul><ul><ul><li>MASSIVE TRANSFUSION </li></ul></ul>
    37. 37. Complications of Crystalloid Fluid Resuscitation <ul><li>Hypothermia </li></ul><ul><li> calcium,  magnesium (Dilutional) </li></ul><ul><li>Coagulopathy </li></ul><ul><ul><li>Dilutional </li></ul></ul><ul><ul><li>Consumptive </li></ul></ul><ul><ul><li>Hypothermia </li></ul></ul><ul><ul><li>Hypocalcemia </li></ul></ul><ul><li>Acidosis non-anion gap MA </li></ul><ul><ul><li>Confusion with anion gap MA </li></ul></ul><ul><li>Edema </li></ul>
    38. 38. Complications of Colloid Resuscitation <ul><li>Fluid overload </li></ul><ul><li>Coagulopathy </li></ul><ul><ul><li>Dilutional and direct </li></ul></ul><ul><ul><li> factor VIIIR:Ag and VIIIR:RCo </li></ul></ul><ul><ul><li>theoretically after 2L </li></ul></ul><ul><ul><ul><li>probably overstated </li></ul></ul></ul><ul><li>Platelet aggregation problems </li></ul>
    39. 39. Complications of Blood Transfusion <ul><li>Infectious </li></ul><ul><li>Immunologic </li></ul><ul><li>Fluid overload/pulmonary edema </li></ul><ul><li>Transfusion reactions </li></ul><ul><li>TRALI </li></ul><ul><ul><ul><li>(transfusion related acute lung injury) </li></ul></ul></ul>
    40. 40. Transfusion Reactions
    41. 41. TRALI <ul><li>Noncardiogenic pulmonary edema </li></ul><ul><li>Immune reaction between donor WBC and recipient plasma </li></ul><ul><li>Onset 1-2 hours post transfusion </li></ul><ul><li>RX ETT and diuresis </li></ul><ul><li>Recovery in 96 hours </li></ul><ul><li>Second leading cause of death in transfusion </li></ul>Miller et al. Miller’s Anesthesia 2005
    42. 42. Infection <ul><li>Hepatitis B,C etc </li></ul><ul><li>HIV </li></ul><ul><li>West Nile Virus </li></ul><ul><li>CMV </li></ul><ul><li>Bacterial </li></ul>
    43. 43. Infection Risk (blood products)
    44. 44. Infection Risk (US 2006) <ul><li>HIV 1/2.1 million </li></ul><ul><li>HCV 1/1.9 million </li></ul><ul><li>HBV 1/220,000 </li></ul><ul><li>Don’t forget others- bacterial, syphilis, CJD </li></ul>
    45. 45. Immunologic <ul><li>Immunomodulation and downregulation are important </li></ul><ul><li>Occurs at many levels </li></ul><ul><li>Affects both T and B cell activity </li></ul><ul><li>Improves transplant graft survival but ↑ metastases inpatients with cancer </li></ul>
    46. 46. Fluid in the Critically Ill <ul><li>After restoration of normal hemodynamics many patients in the ICU require large amounts of ongoing fluid support </li></ul><ul><li>The crystalloid vs colloid debate persists in this population </li></ul><ul><li>TRICC trial </li></ul><ul><li>SAFE trial </li></ul>
    47. 47. Transfusion Trigger <ul><li>Bernard et al TRICC trial </li></ul><ul><li>Only applies to patients < 65 y.o. </li></ul><ul><li>In ICU setting </li></ul><ul><li>Excludes patients with acute coronary syndrome (ACS) </li></ul><ul><li>? Application in trauma/resuscitation </li></ul>
    48. 48. TRICC Trial <ul><li>838 critically ill patients with euvolemia randomized to transfusion trigger of 70 or 100 </li></ul><ul><li>Same 30-day mortaIity </li></ul><ul><li>Improved mortality in restrictive strategy for some subgroups </li></ul><ul><ul><li>patients <55 </li></ul></ul><ul><ul><li>APACHE<20 </li></ul></ul>
    49. 49. Albumin Replacement <ul><li>In critically ill patients with albumin <30 randomized to replacement vs no replacement ie not as volume resuscitation </li></ul><ul><li>Albumin level was higher in the treatment arm (31 vs 22) </li></ul><ul><li>Organ function in respiratory, cardiovascular and central nervous system improved more in the albumin group after 7 days p=0.026 </li></ul>
    50. 50. ARDS <ul><li>Fluid strategies in ARDS are different b/c there are overt drawbacks to over resuscitation </li></ul><ul><li>RCT of restrictive fluid strategy improves mortality 25.% vs 28.4% </li></ul><ul><ul><li>Comparison of Two Fluid-Management Strategies in Acute Lung Injury N Engl J Med 2006;354:2564-75. </li></ul></ul><ul><li>25% Albumin plus lasix vs lasix alone improves oxygenation in ARDS patients </li></ul><ul><ul><li>A randomized, controlled trial of furosemide with or without albumin in hypoproteinemic patients with acute lung injury Crit Care Med 2005 Vol. 33, No. 8 </li></ul></ul>
    51. 51. How Much Fluid to Give? <ul><li>Most agree the danger lies in under resuscitation during initial resuscitation </li></ul><ul><li>15% of intravascular volume can be loss without changes in HR, BP, CO but splanchnic volume is reduced by 40% </li></ul><ul><li>Patients with abnormal gut perfusion do worse than those who have normal measurements </li></ul><ul><ul><li>Mythen MG, Webb AR: Intra-operative gut mucosal hypoperfusion is associated with increased post-operative complications and cost. Intensive Care Med 20:99 - 104, 1994 </li></ul></ul>
    52. 52. Acute Pancreatitis <ul><li>Massive third space loss </li></ul><ul><li>Distributive hemodynamics 2 ° to SIRS </li></ul><ul><li>Major mortality (50%) from ARF requiring dialysis </li></ul><ul><li>Once patient adequately resuscitated with volume then consider vasopressors </li></ul>
    53. 53. Pancreatitis <ul><li>Consider resuscitation with LR or Normosol if urine output present </li></ul><ul><li>NS also adequate if large volumes (>4 to 5 L) avoided </li></ul><ul><li>Ensure adequate Hb (i.e. > 70) </li></ul><ul><li>Beware the secondary compartment syndrome from resuscitation! </li></ul>
    54. 54. How Much Fluid? <ul><li>During the initial resuscitation it is more straightforward </li></ul><ul><li>Restoration of normal blood pressure and heart rate </li></ul><ul><li>Markers of end organ perfusion </li></ul><ul><ul><li>Consciousness </li></ul></ul><ul><ul><li>Skin color </li></ul></ul><ul><ul><li>Urine output </li></ul></ul><ul><ul><li>Lactate, ScVO2 </li></ul></ul>
    55. 55. How Much Fluid? <ul><li>It gets more confusing when the patient becomes “wet” from vascular leak syndrome. </li></ul><ul><li>Although they may look like this…they may still be intravascularly deplete </li></ul><ul><li>How can you tell if the patient would still benefit from fluid? </li></ul>
    56. 56. How Much Fluid? <ul><li>JVP, CVP, PAW do not predict fluid responsiveness </li></ul><ul><ul><li>Osman D, Ridel C, Ray P, et al. Cardiac filling pressures are not appropriate to predict hemodynamic response to volume challenge. Crit Care Med 2007;35:64–68. </li></ul></ul><ul><li>Family of curves: depending on ventricular function changes the meaning of an absolute number </li></ul>
    57. 57. How Much Fluid? <ul><li>Much written about changes in arterial waveform during respiratory cycle </li></ul><ul><ul><li>Spontaneous vs positive pressure ventilation </li></ul></ul><ul><ul><li>Low versus high volume ventilation </li></ul></ul><ul><ul><li>Lung compliance </li></ul></ul><ul><ul><li>Changes in BP versus slope of the curve </li></ul></ul><ul><li>But as always, the best solution is also the most ridiculously simple </li></ul>
    58. 58. How Much Fluid? <ul><li>Response to intrinsic fluid bolus by raising the legs </li></ul><ul><ul><li>Monnet X, Rienzo M, Osman D, et al. Passive leg raising predicts fluid responsiveness in the critically ill. Crit Care Med 2006; 34:1402–1407. </li></ul></ul><ul><ul><li>Boulain T, Achard JM, Teboul JL, et al. Changes in BP induced by passive leg raising predict response to fluid loading in critically ill patients. Chest 2002; 121:1245–1252. </li></ul></ul><ul><li>Changes in aortic blood flow with 45 0 leg elevation was equivalent to that seen with a 500ml crystalloid fluid challenge </li></ul>
    59. 59. Summary <ul><li>There are pros and cons of crystalloids and colloids </li></ul><ul><li>Choice of one over the other is based upon the patient’s physiology </li></ul><ul><li>Determination of a patient’s fluid status can be difficult and we often overestimate the intravascular volume </li></ul><ul><li>Amount of fluid and fluid choice has an important impact on patient outcome </li></ul>