PERIOPERATIVE FLUID PERIOPERATIVE FLUID

THERAPYTHERAPY

Department of Anesthesiology &ICUKKUH. King Saud University

Total Body Water (TBW)Total Body Water (TBW)

• Varies with age, genderVaries with age, gender• 55%55% body weight in males body weight in males• 45%45% body weight in females body weight in females• 80%80% body weight in infants body weight in infants• Less in obese: fat contains little waterLess in obese: fat contains little water

Body Water CompartmentsBody Water Compartments

• Intracellular water: 2/3 of TBWIntracellular water: 2/3 of TBW• Extracellular water: 1/3 TBWExtracellular water: 1/3 TBW

-- Extravascular water: 3/4 of extracellular water Extravascular water: 3/4 of extracellular water

-- Intravascular water: 1/4 of extracellular water Intravascular water: 1/4 of extracellular water

Fluid and Electrolyte RegulationFluid and Electrolyte Regulation

• Volume RegulationVolume Regulation- Antidiuretic HormoneAntidiuretic Hormone- Renin/angiotensin/aldosterone systemRenin/angiotensin/aldosterone system- Baroreceptors in carotid arteries and aortaBaroreceptors in carotid arteries and aorta- Stretch receptors in atrium and juxtaglomerular Stretch receptors in atrium and juxtaglomerular

aparatusaparatus- CortisolCortisol

Fluid and Electrolyte RegulationFluid and Electrolyte Regulation

• Plasma Plasma OsmolalityOsmolality Regulation Regulation- Arginine-Vasopressin (ADH)Arginine-Vasopressin (ADH)- Central and Peripheral osmoreceptorsCentral and Peripheral osmoreceptors

• SodiumSodium Concentration Regulation Concentration Regulation- Renin/angiotensin/aldosterone systemRenin/angiotensin/aldosterone system- Macula Densa of JG apparatusMacula Densa of JG apparatus

Preoperative EvaluationPreoperative Evaluationof Fluid Statusof Fluid Status

• Factors to Assess:Factors to Assess:- h/o intake and outputh/o intake and output- blood pressure: supine blood pressure: supine andand standing standing- heart rateheart rate- skin turgorskin turgor- urinary outputurinary output- serum electrolytes/osmolarityserum electrolytes/osmolarity- mental statusmental status

Orthostatic HypotensionOrthostatic Hypotension

• Systolic blood pressure Systolic blood pressure decreasedecrease of greater than of greater than 20mmHg20mmHg from supine to standing from supine to standing

• Indicates fluid Indicates fluid deficitdeficit of of 6-8%6-8% body weight body weight-- Heart rate should increase as a compensatory measure Heart rate should increase as a compensatory measure-- If no increase in heart rate, may indicate autonomic dysfunction If no increase in heart rate, may indicate autonomic dysfunction

or antihypertensive drug therapyor antihypertensive drug therapy

Perioperative Fluid RequirementsPerioperative Fluid Requirements

The following factors must be taken into account:The following factors must be taken into account:

1- 1- MMaintenance fluid requirementsaintenance fluid requirements

2- 2- NPONPO and other deficits: NG suction, bowel prep and other deficits: NG suction, bowel prep

3- 3- TThird space losseshird space losses

4- 4- RReplacement of blood losseplacement of blood loss

5- Special additional losses: diarrhea5- Special additional losses: diarrhea

1- Maintenance Fluid Requirements1- Maintenance Fluid Requirements

• Insensible losses such as evaporation of water from Insensible losses such as evaporation of water from respiratory tract, sweat, feces, urinary excretion.respiratory tract, sweat, feces, urinary excretion. Occurs continuallyOccurs continually..

• Adults: approximately Adults: approximately 1.5 ml/kg/hr1.5 ml/kg/hr• ““4-2-1 Rule”4-2-1 Rule”

-- 4 ml/kg/hr for the first 10 kg of body weight 4 ml/kg/hr for the first 10 kg of body weight-- 2 ml/kg/hr for the second 10 kg body weight 2 ml/kg/hr for the second 10 kg body weight-- 1 ml/kg/hr subsequent kg body weight 1 ml/kg/hr subsequent kg body weight-- Extra fluid for fever, tracheotomy, denuded surfaces Extra fluid for fever, tracheotomy, denuded surfaces

2- NPO and other deficits2- NPO and other deficits

• NPO deficit = number of hours NPO x NPO deficit = number of hours NPO x maintenance fluid requirement.maintenance fluid requirement.

• Bowel prep may result in up to 1 L fluid loss.Bowel prep may result in up to 1 L fluid loss.• Measurable fluid losses, e.g. NG suctioning, Measurable fluid losses, e.g. NG suctioning,

vomiting, ostomy output, biliary fistula and tube.vomiting, ostomy output, biliary fistula and tube.

3- Third Space Losses3- Third Space Losses

• Isotonic transfer of ECF from Isotonic transfer of ECF from functionalfunctional body body fluid compartments to fluid compartments to non-functionalnon-functional compartments.compartments.

• Depends on location and duration of surgical Depends on location and duration of surgical procedure, amount of tissue trauma, ambient procedure, amount of tissue trauma, ambient temperature, room ventilation.temperature, room ventilation.

Replacing Third Space LossesReplacing Third Space Losses

• Superficial surgical trauma: 1-Superficial surgical trauma: 1-22 ml/kg/hrml/kg/hr• Minimal Surgical Trauma: 3-Minimal Surgical Trauma: 3-44 ml/kg/hrml/kg/hr

- - head and neck, hernia, knee surgery head and neck, hernia, knee surgery

• Moderate Surgical Trauma: 5-Moderate Surgical Trauma: 5-66 ml/kg/hr ml/kg/hr-- hysterectomy, chest surgery hysterectomy, chest surgery

• Severe surgical trauma: Severe surgical trauma: 88-10 ml/kg/hr (or more)-10 ml/kg/hr (or more)-- AAA repair, nehprectomy AAA repair, nehprectomy

4- Blood Loss4- Blood Loss

• Replace Replace 3 cc3 cc of crystalloid solution per cc of of crystalloid solution per cc of blood loss (crystalloid solutions leave the blood loss (crystalloid solutions leave the intravascular space)intravascular space)

• When using blood products or colloids replace When using blood products or colloids replace blood loss volume per volumeblood loss volume per volume

5- Other additional losses5- Other additional losses

• Ongoing fluid losses from other sites:Ongoing fluid losses from other sites:-- gastric drainage gastric drainage-- ostomy output ostomy output-- diarrhea diarrhea

• Replace volume per volume with crystalloid Replace volume per volume with crystalloid solutionssolutions

ExampleExample

• 62 y/o male, 80 kg, for hemicolectomy62 y/o male, 80 kg, for hemicolectomy• NPO after 2200, surgery at 0800, received bowel NPO after 2200, surgery at 0800, received bowel

prepprep• 3 hr. procedure, 500 cc blood loss3 hr. procedure, 500 cc blood loss• What are his estimated intraoperative fluid What are his estimated intraoperative fluid

requirements?requirements?

Example (cont.)Example (cont.)

• Fluid deficit (NPO)Fluid deficit (NPO): 1.5 ml/kg/hr x 10 hrs = 1200 ml + : 1.5 ml/kg/hr x 10 hrs = 1200 ml + 1000 ml for bowel prep = 2200 ml total deficit: (Replace 1000 ml for bowel prep = 2200 ml total deficit: (Replace 1/2 first hr, 1/4 2nd hr, 1/4 3rd hour).1/2 first hr, 1/4 2nd hr, 1/4 3rd hour).

• MaintenanceMaintenance:: 1.5 ml/kg/hr x 3hrs = 360mls 1.5 ml/kg/hr x 3hrs = 360mls• Third Space LossesThird Space Losses:: 6 ml/kg/hr x 3 hrs =1440 mls 6 ml/kg/hr x 3 hrs =1440 mls• Blood LossBlood Loss:: 500ml x 3 = 1500ml 500ml x 3 = 1500ml• TotalTotal = 2200+360+1440+1500=5500mls = 2200+360+1440+1500=5500mls

Intravenous Fluids:Intravenous Fluids:

• Conventional CrystalloidsConventional Crystalloids• ColloidsColloids• Hypertonic SolutionsHypertonic Solutions• Blood/blood products and blood substitutesBlood/blood products and blood substitutes

CrystalloidsCrystalloids

• Combination of Combination of water and electrolyteswater and electrolytes-- Balanced salt solution: electrolyte composition and Balanced salt solution: electrolyte composition and

osmolality similar to plasma; example: lactated osmolality similar to plasma; example: lactated Ringer’s, Plasmlyte, Normosol.Ringer’s, Plasmlyte, Normosol.

- Hypotonic salt solution: electrolyte composition lower Hypotonic salt solution: electrolyte composition lower than that of plasma; example: Dthan that of plasma; example: D55W.W.

- Hypertonic salt solution: 2.7% NaCl.Hypertonic salt solution: 2.7% NaCl.

ColloidsColloids

• Fluids containing Fluids containing molecules molecules sufficiently large sufficiently large enough to prevent transfer across capillary enough to prevent transfer across capillary membranes.membranes.

• Solutions stay in the space into which they are Solutions stay in the space into which they are infused.infused.

• Examples: hetastarch (Hespan), albumin, dextran.Examples: hetastarch (Hespan), albumin, dextran.

Hypertonic SolutionsHypertonic Solutions

• Fluids containing sodium concentrations greater than Fluids containing sodium concentrations greater than normal saline.normal saline.

• Available in 1.8%, 2.7%, 3%, 5%, 7.5%, 10% solutions.Available in 1.8%, 2.7%, 3%, 5%, 7.5%, 10% solutions.• Hyperosmolarity Hyperosmolarity creates a gradient that draws water out creates a gradient that draws water out

of cells; therefore, cellular dehydration is a potential of cells; therefore, cellular dehydration is a potential problem.problem.

CompositionComposition

Fluid Osmo-lality

Na Cl K

D5W 253 0 0 0

0.9NS 308 154 154 0

LR 273 130 109 4.0

Plasma-lyte 294 140 98 5.0

Hespan 310 154 154 0

5% Albumin 308 145 145 0

3%Saline 1027 513 513 0

Clinical Evaluation of Fluid Clinical Evaluation of Fluid ReplacementReplacement

1. Urine Output: at least 1.0 ml/kg/hr1. Urine Output: at least 1.0 ml/kg/hr2. Vital Signs: BP and HR normal (How is the patient 2. Vital Signs: BP and HR normal (How is the patient

doing?)doing?)3. Physical Assessment: Skin and mucous membranes no 3. Physical Assessment: Skin and mucous membranes no

dry; no thirst in an awake patientdry; no thirst in an awake patient4. Invasive monitoring; CVP or PCWP may be used as a 4. Invasive monitoring; CVP or PCWP may be used as a

guide guide5. Laboratory tests: periodic monitoring of hemoglobin and 5. Laboratory tests: periodic monitoring of hemoglobin and

hematocrithematocrit

SummarySummary• Fluid therapy is critically important during the Fluid therapy is critically important during the

perioperative period.perioperative period.• The most important goal is to maintain The most important goal is to maintain

hemodynamic stability and protect vital organs hemodynamic stability and protect vital organs from hypoperfusion (heart, liver, brain, kidneys).from hypoperfusion (heart, liver, brain, kidneys).

• All sources of fluid losses must be accounted for.All sources of fluid losses must be accounted for.• Good fluid management goes a long way toward Good fluid management goes a long way toward

preventing problems.preventing problems.

Transfusion TherapyTransfusion Therapy

-- 60% of transfusions occur perioperatively.60% of transfusions occur perioperatively.

-- responsibility of transfusing perioperatively is with the responsibility of transfusing perioperatively is with the anesthesiologist.anesthesiologist.

When is Transfusion Necessary?When is Transfusion Necessary?

• ““Transfusion TriggerTransfusion Trigger”: Hgb level at which ”: Hgb level at which transfusion should be given.transfusion should be given.-- Varies with patients and procedures Varies with patients and procedures

• Tolerance of acute anemia depends on:Tolerance of acute anemia depends on:-- Maintenance of intravascular volume Maintenance of intravascular volume- - Ability to increase cardiac output Ability to increase cardiac output-- Increases in 2,3-DPG to deliver more of the carried Increases in 2,3-DPG to deliver more of the carried

oxygen to tissuesoxygen to tissues

Oxygen DeliveryOxygen Delivery

• Oxygen Delivery (DOOxygen Delivery (DO22) is the oxygen that is ) is the oxygen that is

delivered to the tissuesdelivered to the tissues

DODO22= COP x CaO= COP x CaO22

• Cardiac Output (CO) = HR x SV Cardiac Output (CO) = HR x SV

• Oxygen Content (CaOOxygen Content (CaO22):):

-- ( (HgbHgb x 1.39)O x 1.39)O22 saturation + PaO saturation + PaO22(0.003)(0.003)

-- Hgb is the main determinant of oxygen content in the blood Hgb is the main determinant of oxygen content in the blood

Oxygen DeliveryOxygen Delivery (cont.) (cont.)

• Therefore: Therefore: DODO22 = HR x SV x CaO = HR x SV x CaO22

• If HR or SV are unable to compensate, Hgb is the If HR or SV are unable to compensate, Hgb is the major deterimant factor in Omajor deterimant factor in O22 delivery delivery

• Healthy patients have excellent compensatory Healthy patients have excellent compensatory mechanisms and can tolerate Hgb levels of 7 mechanisms and can tolerate Hgb levels of 7 gm/dL.gm/dL.

• Compromised patients may require Hgb levels Compromised patients may require Hgb levels above 10 gm/dL.above 10 gm/dL.

Blood GroupsBlood Groups

Antigen onAntigen on Plasma Plasma IncidenceIncidence

Blood GroupBlood Group erythrocyteerythrocyte AntibodiesAntibodies WhiteWhite African-African-AmericansAmericans

AA AA Anti-BAnti-B 40%40% 27%27%BB BB Anti-AAnti-A 1111 2020ABAB ABAB NoneNone 44 44OO NoneNone Anti-AAnti-A 4545 4949

Anti-BAnti-BRhRh RhRh 4242 1717

Cross MatchCross Match• Major:Major:

-- Donor’s erythrocytes incubated with recipients plasmaDonor’s erythrocytes incubated with recipients plasma

• Minor:Minor:-- Donor’s plasma incubated with recipients erythrocytes Donor’s plasma incubated with recipients erythrocytes

• Agglutination:Agglutination:-- Occurs if either is incompatible Occurs if either is incompatible

• Type Specific:Type Specific:-- Only ABO-Rh determined; chance of hemolytic reaction is Only ABO-Rh determined; chance of hemolytic reaction is

1:1000 with TS blood1:1000 with TS blood

Type and ScreenType and Screen

• Donated blood that has been tested for ABO/Rh Donated blood that has been tested for ABO/Rh antigens and screened for common antibodies antigens and screened for common antibodies (not mixed with recipient blood).(not mixed with recipient blood).- - Used when usage of blood is unlikely, but needs to be Used when usage of blood is unlikely, but needs to be

available (hysterectomy).available (hysterectomy).

-- Allows blood to available for other patients. Allows blood to available for other patients.

-- Chance of hemolytic reaction: 1:10,000. Chance of hemolytic reaction: 1:10,000.

Component TherapyComponent Therapy

• A unit of whole blood is divided into components; Allows A unit of whole blood is divided into components; Allows prolonged storage and specific treatment of underlying problem prolonged storage and specific treatment of underlying problem with increased efficiency:with increased efficiency:

- packed red blood cells (pRBC’s)packed red blood cells (pRBC’s)- platelet concentrateplatelet concentrate- fresh frozen plasma (contains all clotting factors)fresh frozen plasma (contains all clotting factors)- cryoprecipitate (contains factors VIII and fibrinogen; used in Von cryoprecipitate (contains factors VIII and fibrinogen; used in Von

Willebrand’s disease)Willebrand’s disease)- albumin albumin - plasma protein fractionplasma protein fraction- leukocyte poor blood leukocyte poor blood - factor VIIIfactor VIII- antibody concentratesantibody concentrates

Packed Red Blood CellsPacked Red Blood Cells

• 1 unit = 250 ml. Hct. = 70-80%.1 unit = 250 ml. Hct. = 70-80%.• 1 unit pRBC’s raises Hgb 1 gm/dL.1 unit pRBC’s raises Hgb 1 gm/dL.• Mixed with saline: LR has Calcium which may Mixed with saline: LR has Calcium which may

cause clotting if mixed with pRBC’s.cause clotting if mixed with pRBC’s.

Platelet ConcentratePlatelet Concentrate

• Treatment of thrombocytopeniaTreatment of thrombocytopenia• Intraoperatively used if platlet count drops below 50,000 Intraoperatively used if platlet count drops below 50,000

cells-mmcells-mm33 (lab analysis). (lab analysis).• 1 unit of platelets increases platelet count 5000-10000 1 unit of platelets increases platelet count 5000-10000

cells-mmcells-mm3.3.

• Risks:Risks:- Sensitization due to HLA on platelets- Sensitization due to HLA on platelets

- Viral transmission- Viral transmission

FFreshresh F Frozenrozen P Plasmalasma

• Plasma from whole blood frozen within 6 hours of Plasma from whole blood frozen within 6 hours of collection.collection.- Contains coagulation factors except plateletsContains coagulation factors except platelets- Used for treatment of isolated factor deficiences, reversal of Used for treatment of isolated factor deficiences, reversal of

Coumadin effect, TTP, etc.Coumadin effect, TTP, etc.- Used when PT and PTT are >1.5 normalUsed when PT and PTT are >1.5 normal

• Risks:Risks:- Viral transmissionViral transmission- AllergyAllergy

Complications of Blood TherapyComplications of Blood Therapy

• Transfusion Reactions:Transfusion Reactions:- - FebrileFebrile;; most common, usually controlled by slowing most common, usually controlled by slowing

infusion and giving antipyreticsinfusion and giving antipyretics

- - AllergicAllergic;; increased body temp., pruritis, urticaria. Rx: increased body temp., pruritis, urticaria. Rx: antihistamine,discontinuation. Examination of plasma antihistamine,discontinuation. Examination of plasma and urine for free hemoglobin helps rule out hemolytic and urine for free hemoglobin helps rule out hemolytic reactions.reactions.

Complications of Blood TherapyComplications of Blood Therapy (cont.)(cont.)

• Hemolytic: Hemolytic: - Wrong blood type administered (oops).Wrong blood type administered (oops).- Activation of complement system leads to intravascular Activation of complement system leads to intravascular

hemolysis, spontaneous hemorrhage.hemolysis, spontaneous hemorrhage.- Signs: hypotension,fever, chills, dyspnea, skin flushing, Signs: hypotension,fever, chills, dyspnea, skin flushing,

substernal pain. Signs are easily masked by general anesthesia.substernal pain. Signs are easily masked by general anesthesia.- Free Hgb in plasma or urine Free Hgb in plasma or urine - Acute renal failureAcute renal failure- Disseminated Intravascular Coagulation (DIC)Disseminated Intravascular Coagulation (DIC)

Complications (cont.)Complications (cont.)

• Transmission of Viral Diseases:Transmission of Viral Diseases:- Hepatitis C; 1:30,000 per unitHepatitis C; 1:30,000 per unit- Hepatitis B; 1:200,000 per unitHepatitis B; 1:200,000 per unit- HIV; 1:450,000-1:600,000 per unitHIV; 1:450,000-1:600,000 per unit- 22 day window for HIV infection and test detection22 day window for HIV infection and test detection- CMV may be the most common agent transmitted, but CMV may be the most common agent transmitted, but

only effects immuno-compromised patientsonly effects immuno-compromised patients- Parasitic and bacterial transmission very lowParasitic and bacterial transmission very low

Other ComplicationsOther Complications

- Decreased 2,3-DPG with storage: ? SignificanceDecreased 2,3-DPG with storage: ? Significance- Citrate: metabolism to bicarbonate; Calcium bindingCitrate: metabolism to bicarbonate; Calcium binding- Microaggregates (platelets, leukocytes): micropore Microaggregates (platelets, leukocytes): micropore

filters controversialfilters controversial- Hypothermia: warmers used to preventHypothermia: warmers used to prevent- Coagulation disorders: massive transfusion (>10 units) Coagulation disorders: massive transfusion (>10 units)

may lead to dilution of platelets and factor V and VIII.may lead to dilution of platelets and factor V and VIII.- DIC: uncontrolled activation of coagulation systemDIC: uncontrolled activation of coagulation system

Treatment of Acute Hemolytic Treatment of Acute Hemolytic ReactionsReactions

• Immediate Immediate discontinuationdiscontinuation of blood products and of blood products and send blood bags to lab.send blood bags to lab.

• Maintenance of urine output with crystalloid Maintenance of urine output with crystalloid infusionsinfusions

• Administration of mannitol or Furosemide for Administration of mannitol or Furosemide for diuretic effectdiuretic effect

Autologous BloodAutologous Blood

• Pre-donation of patient’s own blood prior to Pre-donation of patient’s own blood prior to elective surgeryelective surgery

• 1 unit donated every 4 days (up to 3 units)1 unit donated every 4 days (up to 3 units)• Last unit donated at least 72 hrs prior to surgeryLast unit donated at least 72 hrs prior to surgery• Reduces chance of hemolytic reactions and Reduces chance of hemolytic reactions and

transmission of blood-bourne diseasestransmission of blood-bourne diseases• Not desirable for compromised patientsNot desirable for compromised patients

Administering Blood ProductsAdministering Blood Products

- Consent necessary for elective transfusionConsent necessary for elective transfusion- Unit is checked by 2 people for Unit #, patient ID, Unit is checked by 2 people for Unit #, patient ID,

expiration date, physical appearance.expiration date, physical appearance.- pRBC’s are mixed with saline solution (not LR)pRBC’s are mixed with saline solution (not LR)- Products are warmed mechanically and given slowly if Products are warmed mechanically and given slowly if

condition permitscondition permits- Close observation of patient for signs of complicationsClose observation of patient for signs of complications- If complications suspected, infusion discontinued, If complications suspected, infusion discontinued,

blood bank notified, proper steps taken.blood bank notified, proper steps taken.

Alternatives to Blood ProductsAlternatives to Blood Products

• AutotransfusionAutotransfusion• Blood substitutesBlood substitutes

AutotransfusionAutotransfusion

• Commonly known as Commonly known as “Cell-saver”“Cell-saver”• Allows collection of blood during surgery for re-Allows collection of blood during surgery for re-

administrationadministration• RBC’s centrifuged from plasmaRBC’s centrifuged from plasma• Effective when > 1000ml are collectedEffective when > 1000ml are collected

Blood SubstitutesBlood Substitutes

• Experimental oxygen-carrying solutions: developed to Experimental oxygen-carrying solutions: developed to decrease dependence on human blood productsdecrease dependence on human blood products

• Military battlefield usage initial goalMilitary battlefield usage initial goal• Multiple approaches:Multiple approaches:

- Outdated human Hgb reconstituted in solutionOutdated human Hgb reconstituted in solution

- Genetically engineered/bovine Hgb in solutionGenetically engineered/bovine Hgb in solution

- Liposome-encapsulated Hgb Liposome-encapsulated Hgb

- PerflurocarbonsPerflurocarbons

Blood SubstitutesBlood Substitutes (cont.) (cont.)

• Potential Advantages:Potential Advantages:- No cross-match requirementsNo cross-match requirements- Long-term shelf storageLong-term shelf storage- No blood-bourne transmissionNo blood-bourne transmission- Rapid restoration of oxygen delivery in traumatized Rapid restoration of oxygen delivery in traumatized

patientspatients- Easy access to product (available on ambulances, field Easy access to product (available on ambulances, field

hospitals, hospital ships)hospitals, hospital ships)

Blood SubstitutesBlood Substitutes (cont.) (cont.)

• Potential Disadvantages:Potential Disadvantages:-- Undesirable hemodynamic effects: Undesirable hemodynamic effects:

• Mean arterial pressure and pulmonary artery pressure Mean arterial pressure and pulmonary artery pressure increasesincreases

- Short half-life in bloodstream (24 hrs)Short half-life in bloodstream (24 hrs)- Still in clinical trials, unproven efficacyStill in clinical trials, unproven efficacy- High costHigh cost

Transfusion Therapy SummaryTransfusion Therapy Summary

• Decision to transfuse involves many factorsDecision to transfuse involves many factors• Availability of component factors allows Availability of component factors allows

treatment of specific deficiencytreatment of specific deficiency• Risks of transfusion must be understood and Risks of transfusion must be understood and

explained to patientsexplained to patients• Vigilance necessary when transfusing any blood Vigilance necessary when transfusing any blood

productproduct