Update on Fluid Resuscitation

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: maday@uab.edu

Twitter: @PA_Maday