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Fluid ResuscitationFrom The Basics To Being A Resuscitationist
Kristopher R. Maday, MS, PA-C, CNSCUniversity of Alabama at Birmingham
Physician Assistant ProgramPegasus Emergency Group
No Professional or Commercial Interests to Disclose
Objectives• IV Access and types of IVF• Fluid dynamics and physiology• Criteria for assessing volume status and
fluid responsiveness• How to become a Resuscitationist
Resuscitation 101
Intravenous Access• Peripheral IV– Standard access
• 14-25 gauge– Pros
• Quick, inexpensive• Lower infection risk
– Cons• Short term– Need to rotate every 72-96 hr
• Blow outCheung E, et all. Canadian Family Physician. 2009;55:494-496.
Intravenous Access• Central Venous Line– Terminate within the thorax– Indications
• Long term access• High osmolar fluids, vasopressors• Inaccessible peripheral access
– Cons• More technically challenging• Increased infection risk• Iatrogenic complications
Cheung E, et all. Canadian Family Physician. 2009;55:494-496.
Intraosseous Access• Inserted into tibia, sternum, or humerus• Indications– Unable to perform traditional peripheral IV– Bridge to traditional line
• Cons– Unable to infuse rapid volume– Risk of compartment syndrome– Fractures
Day MW. Critical Care Nurse. 2011;31(2):76-89.
Let’s Take You WAAAAAAY Back…….• Poiseuille’s Law– Resistance to flow is dependent on radius and length of tube and viscosity of fluid
– R=(8ηL)/(πr4)• A 2x increase in diameter will yield a 16x increase in
flow
Standard Triple lumen CVL7 fr - 3 lines 18g proximal18g middle16g distal16cmR=146.7
TraumaCath/VasCath8fr - 2 lines14g14g15cmR=54.38
14g peripheral IV3.83cmR=15.26
Normal Body Fluid Composition• Total body water– Gender differences
• Males - 60% of body weight • Females – 50% of body weight
– Components• Intracellular – 2/3 of total body water - 40% of body weight• Extracellular – 1/3 of total body water - 20% of body weight
– Intravascular» 20-25% of extracellular volume» 5% of body weight
– Interstitial » 75-80% of extracellular volume» 15% of body weight
– Obese/elderly – decrease by 10%• Total blood volume - 7% of body weight
Ch. 3. In: Schwartz’s Principles of Surgery. 9th ed. 2010
Fluid Movement• Fluid movement is constant and is
influenced by:– Hydrostatic pressure– Colloid osmotic pressure– Membrane permeability
Ch. 49. In: Morgan and Mikhail’s Clinical Anesthesiology. 5th ed. 2013
Fluid Movement• Hydrostatic pressure– The mechanical force of water pushing against a
membrane. In the intravascular space, it is the pumping action of the heart that generates this force.
– At the arterial end of the capillary, hydrostatic pressure forces water, sodium and glucose across the membrane into the interstitial space
Ch. 49. In: Morgan and Mikhail’s Clinical Anesthesiology. 5th ed. 2013
Fluid Movement• Osmotic Pressure– Movement of fluid between the ICF and ECF is
primarily a function of osmotic forces• Plasma proteins pull water back into the vascular
space at the venous end of the capillary bed– Measurement of solute concentration in serum is
termed osmolarity• Serum osmolarity – 2(Na+) + glucose/18 + BUN/2.8– Normal – 270-290 mOsmo/L– Dehydrated - >290 mOsmo/L– Fluid Overload - <270 mOsmo/L
Ch. 49. In: Morgan and Mikhail’s Clinical Anesthesiology. 5th ed. 2013
Fluid Movement• Membrane permeability– Transport of substances across the
cell membrane depends on the substance to be transported
– Passive• Transport does not require energy
and is accomplished by osmosis, diffusion, or the force of hydrostatic pressure
– Active• Transport requires the expenditure
of metabolic energy by the cell– Larger and electrically charged particles
Ch. 49. In: Morgan and Mikhail’s Clinical Anesthesiology. 5th ed. 2013
Myburgh JA, et al. N Engl J Med. 2013;369:1243-51
Types of IV Fluids• Crystalloids– Hypertonic– Isotonic– Hypotonic
• Dextrose solutions• Colloids– Albumin– Dextran– Hetastarch– Gelatins
Crystalloids• Electrolyte solutions with small molecules that can
diffuse freely throughout the extracellular space• Principle component is NaCl– Most abundant solute in extracellular fluid
Predominant effect of volume resuscitation with crystalloids in to expand interstitial volume, rather than intravascular volume
3 types– Hypertonic– Isotonic– Hypotonic
Crystalloids• Isotonic– 0.9% NaCl (normal saline, NS)– Closer to physiologic norms
• Can produce metabolic acidosis– Allows for larger volume to be infused for
resuscitation– Lactated Ringers (Ringer’s lactate, LR)
• Contains less sodium and chloride, more potassium, more calcium
• Higher pH than NS• Contains lactate which is converted to HCO3- by liverMyburgh JA, et al. N Engl J Med. 2013;369:1243-51
Crystalloids• Hypertonic– 1.5%, 3%, 7%, 23.5% NaCl– Solute concentration higher than the solute
concentration of the serum• Infusion causes an increase in the solute concentration of
the serum, pulling fluid from the interstitial space to the vascular space through osmosis
– Can be used to treat increasing ICP
Myburgh JA, et al. N Engl J Med. 2013;369:1243-51
Crystalloids• Hypotonic – 0.45% NaCl (1/2 NS), 0.225% NaCl (1/4 NS)– Considerably lower osmolarity than serum– Good for fluid maintenance and replacing free
water deficit
Myburgh JA, et al. N Engl J Med. 2013;369:1243-51
Crystalloid Solute Concentration and Effects on pH
Ch. 12. In: The ICU Book. 4th ed. 2013
Dextrose Solutions• Dextrose added to a crystalloid fluid– D5, D10 in NS, 1/2NS, or water
• 1 gram of dextrose provides 3.4 kcal• Benefits– Combat protein catabolism by providing
calories when NPO• D51/2 NS @ 125/hr x 24 hr = 510 kcal
• Disadvantages– Hyperglycemia, hyponatremia, hypertonicity
Colloids• More effective at increasing intravascular volume
because they contain large, poorly diffusible, solutes that create an osmotic pressure to keep water in the vascular space– ***3 times more effective than crystalloids***
• Good for fluid resuscitation in patients with full interstitial reserves
• 4 main types– Albumin– Hetastarch– Dextran– Gelatins
Mitra S, et al. Indian J Anaesth. 2009;53(5):592-607
Ch. 12. In: The ICU Book. 4th ed. 2013
Colloids• Albumin solutions
– 5%, 25%, given in 250mL aliquots– Blood product, so slight risk of
transfusion reaction
• Hydroxyethyl starches (HES)– 6%, 500-1000mL, do not exceed
20mL/kg– Chemically manufactured starch
polymer– Inhibits factor VII and vWF and
impairs platelet aggregationMitra S, et al. Indian J Anaesth. 2009;53(5):592-607
• Dextrans– 10% dextran-40, 6%
dextran-70– Glucose polymer– Inhibits factor VII and vWF,
impairs platelet aggregation, and increases fibrinolysis
– Can cause ARF (unknown)• Gelatins– 4% Succinylated, 3.5% Urea-
crosslinked, Oxypolygelatins– Less reactions, uncommon in
US
Volume Changes with Colloids
Ch. 12. In: The ICU Book. 4th ed. 2013
Resuscitation 201
Who Needs Resuscitation?
Initial Assessment and Resuscitation. In: Current Therapy of Trauma and Surgical Critical Care. 1st ed. 2008
• Labs– Lactate
• Normal - < 2 mg/dL
– Base Deficit• Normal – > -2
Predicting Fluid Responsiveness (Old and Busted)
• Central Venous Pressure – No association between CVP and
circulating blood volume– CVP does not predict fluid
responsiveness• Pulmonary Capillary Wedge Pressure– Risk > Benefit
• Jugular Venous Distension– More accurate modalities
Marik PE. CHEST. 2008;134(1):172-178. Leier CV. Circ Heart Fail. 2010;3:175-177.
• Orthostatic Measurements– Supine and Standing measurement of BP and
HR• Positive test– Decrease in 1) systolic > 20mmHg or diastolic > 10mmHg and 2)
increase in pulse rate 10-25 bpm within 3 min– > 1L blood loss needed for 97%
sensitivity and 98% specificity
Carlson JE. Southern Medical Journal. 1999;92(2):167-173.
Predicting Fluid Responsiveness (Old and Busted)
McGee S et al. JAMA. 1999;280(11):1022-1029
Predicting Fluid Responsiveness (New Hotness)• Passive Leg Raise– Increases venous return in patients who are
preload responsive• Identifies patients on ascending portion of Starling
Curve
Marik PE. Annals of Intensive Care. 2011. 1:1.
45o 45o
• IVC Distensibility– Change in diameter of IVC between end-
inspiration (dMax) and end-expiration (dMin)• dIVC Index – (dMax-dMin)/dMin– > 18% change predicts fluid responsiveness with > 90%
sensitivity and specificity
Barbier C et al. Intensive Care Med. 2004;30:1740-1746
Predicting Fluid Responsiveness (New Hotness)
Barbier C et al. Intensive Care Med. 2004;30:1740-1746
• Stroke Volume Variation (SVV)– Changes in SV during inspiration/expiration– Normal <15%
Michard F. Anesthesiology. 2005;103:419-428
Predicting Fluid Responsiveness (New Hotness)
Resuscitation 301
Endpoints of Resuscitation• 3 main goals to achieve– Restoration of adequate oxygen delivery– Resolution of existing oxygen debt– Elimination of anaerobic metabolites
• Traditional endpoints– HR, BP, mental status, urine output
• Global endpoints– Lactate, base deficit, ScvO2
Rady MY. Crit Care. 2005;9(2):170-176 Goodrich C. AACN Adv Crit Care. 2006;17(3):306-316
Endpoints of Resuscitation• Lactate– Metabolic byproduct of anaerobic metabolism
• Most sensitive marker of tissue perfusion– Lactate clearance and mortality
• < 24 hours – 0%• 24-48 hours – 25%• > 48 hours – 86%
– Higher lactate and duration of hyperlactatemia correlated with increased rates of MODS
Abramson D et al. J Trauma. 1993;35:584-589 Manikis P et al. Am J Emerg Med. 1995;13:619-622
Endpoints of Resuscitation• Base Deficit– Used as a lactate proxy– Grades
• Mild (2-5 mmol/L)• Moderate (6-14 mmol/L)• Severe (> 14 mmol/L)
– Studies have shown:• Elevated initial BD was associated with lower initial BP and
increased fluid requirement• 2/3rd of patients with increasing BD had ongoing blood loss• Increase in BD between ED and ICU had increased risk of
hemodynamic collapse, increased transfusion requirements, coagulopathy, and mortality
Tisherman SA et al. J Trauma. 2004;57:898-912 Davis JW et al. J Trauma. 1988;44:1464-1467 Rixen D et al. Shock. 2001;15:83-89
Endpoints of Resuscitation• Central Venous Oxygen Saturation (ScvO2)– Proxy of mixed venous oxygen saturation
(SvO2)• Global indicator of the balance of O2 delivery and O2
consumption– < 70% suggests tissue hypoperfusion– Need CVL or PA catheter
Rivers E et al.N Eng J Med. 2001;345(19):1368-1377
Oxygen DeliveryDO2=Qx[1.39x(Hgb)(SaO2)+(0.003xPaO2)
Resuscitation 401
Hemostatic Resuscitation• Used in the acutely bleeding trauma patient• Benefits– Maintains circulating volume– Limits IVF administration
• Uses blood products instead of crystalloids– Limits ongoing hemorrhage
• Revolves around 2 principles– Permissive hypotension– Aggressive blood product use
Permissive Hypotension
• Balance of maintaining adequate perfusion, but preventing exsanguination until surgical bleeding can be controlled– Target = MAP of 65 mmHg
• If MAP < 65, then resuscitate with IVF or products• If MAP > 65, then check perfusion
– Good perfusion Masterful inactivity– Poor perfusion Fentanyl
• Special considerations– Non-hemorrhagic causes of hypotension, TBI
“Injection of a fluid that will increase blood pressure has dangers in itself…If the pressure is raised before the surgeon is ready to check any bleeding that might take place, blood that is sorely needed may be lost” Cannon W. JAMA 1918;70:618-621
Dutton RP et al. J Trauma. 2002;52(6):1141-1146 Wiles MD. Anaesthesia. 2013;68(5):445-449
Massive Transfusion• Roots in the military and started gaining civilian traction
in mid 2000s• 2 principles– Replace what is lost– Prevent coagulopathy before it develops
• Multiple definitions of triggers• Shoot for a 1:1:1 of blood products– 1 unit PRBC – 335ml, Hct 55%– 1 unit FFP – 275ml, 80% coagulation activity– 1 unit Plt – 50ml, 3x1011
• Use hemostatic adjuncts– Transexamic acid, Prothrombin Complex Concentrate
Richard Dutton, “Hemostatic Resuscitation”, EM Crit Conference Lecture, 2011
57yo male with AMS, BP-82/50 (MAP-60), HR-114, RR-23, O2-89% on RA
IVC U/S shows dIVC 73%, Intubate, NGT placed
A-line and 18g PIV x 2 placed, FloTrac shows SVV 31% and CI 3.4, ABG shows BD -11, Lactate 4.2
2L LR bolus, Labs sent, Foley placed (~50cc)
SVV 16%, BD -10, BP-81/54 (MAP-62), HR-111, Lactate 4.0
R IJ CVL placed, ScvO2 59%, Hgb 7.4, INR 2.8, EtOH 321, BUN 63
4U PRBC, 4U FFP, 25mcg Fentanyl SVV 11%, CI 3.2, BD -6, Lactate 2.8, Hgb 9.1, INR 2.4
BP-102/72 (MAP 81), HR-94, O2-98%
ScvO2
> 70%
< 70% SaO2
< 92%
O2
Intubate
> 92% CI
< 2.5
> 2.5
Hgb
> 8.0 < 8.0
Sedation Transfuse
VolumeStatus
SVV < 15%
SVV > 15%
Pressors
Volume
Check Perfusion
How to be a Resuscitationist• Critically evaluate patients who may need
volume• Identify the need and type of access • Select appropriate fluid and know the
expected physiologic changes• Interpret endpoints of resuscitation• Assess special populations for more
aggressive management
Questions, Comments, Concerns, Criticisms
Kristopher R. Maday, MS, PA-C, CNSCUAB Physician Assistant Program
Pegasus Emergency GroupEmail: [email protected]
Twitter: @PA_Maday