2Fluid Requirements and Fluid Therapy Lecture Objectives..Students at the end of the lecture will be able to:know aboutFluid Requirements and Fluid TherapyWhat perioperative factors affect the patient’s fluid requirements?How do you estimate maintenance fluid requirements?What are some common conditions associated with preoperative fluid deficits?List the potential physical and laboratory findings seen in a patient with a volume deficit.How do you calculate the patient’s preoperative fluid deficits?
3Intravenous Fluids Crystalloids What is the difference between normal saline, and Ringer's lactate?What are the advantages and disadvantages of crystalloids?ColloidsWhat colloid preparations are available for clinical use?What are some advantages and potential side effects of hetastarch?When to use 5% or 25% albumin preparation in volume resuscitation?When is plasma indicated?
4Blood ProductsWhat is the minimal acceptable hemoglobin? What factors affect the minimal acceptable hemoglobin level?How do you calculate the acceptable blood loss during surgery?What is the difference between autologous and banked blood?What are the routine screening tests of banked blood?What administration set do you use for red blood cell, plasma and platelet transfusion?How much increase in Hb level do you expect from transfusing one unit of RBCs?What side effects can occur with the transfusion of blood products?What are the side-effects (potential complications) of massive or rapid blood transfusion?What is the indication for the transfusion of fresh frozen plasma, cryoprecipitate, and platelets?
5Total Body Water (TBW) Varies with age, gender 55% body weight in males45% body weight in females80% body weight in infantsLess in obese: fat contains little water
6Body Water Compartments Intracellular water: 2/3 of TBWExtracellular water: 1/3 TBW- Extravascular water: 3/4 of extracellular water- Intravascular water: 1/4 of extracellular water
7Fluid and Electrolyte Regulation Volume RegulationAntidiuretic HormoneRenin/angiotensin/aldosterone systemBaroreceptors in carotid arteries and aortaStretch receptors in atrium and juxtaglomerular aparatusCortisol
8Fluid and Electrolyte Regulation Plasma Osmolality RegulationArginine-Vasopressin (ADH)Central and Peripheral osmoreceptorsSodium Concentration RegulationRenin/angiotensin/aldosterone systemMacula Densa of JG apparatus
9Preoperative Evaluation of Fluid Status Factors to Assess:h/o intake and outputblood pressure: supine and standingheart rateskin turgorurinary outputserum electrolytes/osmolaritymental status
10Orthostatic Hypotension Systolic blood pressure decrease of greater than 20mmHg from supine to standingIndicates fluid deficit of 6-8% body weight- Heart rate should increase as a compensatory measure- If no increase in heart rate, may indicate autonomic dysfunction or antihypertensive drug therapy
11Perioperative Fluid Requirements The following factors must be taken into account: 1- Maintenance fluid requirements 2- NPO and other deficits: NG suction, bowel prep 3- Third space losses 4- Replacement of blood loss 5- Special additional losses: diarrhea
121- Maintenance Fluid Requirements Insensible losses such as evaporation of water from respiratory tract, sweat, feces, urinary excretion. Occurs continually.Adults: approximately 1.5 ml/kg/hr“4-2-1 Rule”- 4 ml/kg/hr for the first 10 kg of body weight- 2 ml/kg/hr for the second 10 kg body weight- 1 ml/kg/hr subsequent kg body weight- Extra fluid for fever, tracheotomy, denuded surfaces
132- NPO and other deficits NPO deficit = number of hours NPO x maintenance fluid requirement.Bowel prep may result in up to 1 L fluid loss.Measurable fluid losses, e.g. NG suctioning, vomiting, ostomy output, biliary fistula and tube.
143- Third Space LossesIsotonic transfer of ECF from functional body fluid compartments to non-functional compartments.Depends on location and duration of surgical procedure, amount of tissue trauma, ambient temperature, room ventilation.
15Replacing Third Space Losses Superficial surgical trauma: 1-2 ml/kg/hrMinimal Surgical Trauma: 3-4 ml/kg/hr- head and neck, hernia, knee surgeryModerate Surgical Trauma: 5-6 ml/kg/hr- hysterectomy, chest surgerySevere surgical trauma: 8-10 ml/kg/hr (or more)- AAA repair, nehprectomy
164- Blood LossReplace 3 cc of crystalloid solution per cc of blood loss (crystalloid solutions leave the intravascular space)When using blood products or colloids replace blood loss volume per volume
175- Other additional losses Ongoing fluid losses from other sites:- gastric drainage- ostomy output- diarrheaReplace volume per volume with crystalloid solutions
18Example 62 y/o male, 80 kg, for hemicolectomy NPO after 2200, surgery at 0800, received bowel prep3 hr. procedure, 500 cc blood lossWhat are his estimated intraoperative fluid requirements?
19Example (cont.)Fluid deficit (NPO): 1.5 ml/kg/hr x 10 hrs = 1200 ml ml for bowel prep = 2200 ml total deficit: (Replace 1/2 first hr, 1/4 2nd hr, 1/4 3rd hour).Maintenance: 1.5 ml/kg/hr x 3hrs = 360mlsThird Space Losses: 6 ml/kg/hr x 3 hrs =1440 mlsBlood Loss: 500ml x 3 = 1500mlTotal = =5500mls
21Crystalloids Combination of water and electrolytes - Balanced salt solution: electrolyte composition and osmolality similar to plasma; example: lactated Ringer’s, Plasmlyte, Normosol.Hypotonic salt solution: electrolyte composition lower than that of plasma; example: D5W.Hypertonic salt solution: 2.7% NaCl.
22ColloidsFluids containing molecules sufficiently large enough to prevent transfer across capillary membranes.Solutions stay in the space into which they are infused.Examples: hetastarch (Hespan), albumin, dextran.
23Hypertonic SolutionsFluids containing sodium concentrations greater than normal saline.Available in 1.8%, 2.7%, 3%, 5%, 7.5%, 10% solutions.Hyperosmolarity creates a gradient that draws water out of cells; therefore, cellular dehydration is a potential problem.
25Clinical Evaluation of Fluid Replacement 1. Urine Output: at least 1.0 ml/kg/hr 2. Vital Signs: BP and HR normal (How is the patient doing?) 3. Physical Assessment: Skin and mucous membranes no dry; no thirst in an awake patient 4. Invasive monitoring; CVP or PCWP may be used as a guide 5. Laboratory tests: periodic monitoring of hemoglobin and hematocrit
26SummaryFluid therapy is critically important during the perioperative period.The most important goal is to maintain hemodynamic stability and protect vital organs from hypoperfusion (heart, liver, brain, kidneys).All sources of fluid losses must be accounted for.Good fluid management goes a long way toward preventing problems.
27Blood Products and blood transfusion Dr. Jumana BaajConsultant anesthesit - Assistant professorKKUH – KSU15 / 9 /2013Blood Products and blood transfusion
28Objective Blood transfusion complication treatment Indication of blood transfusionBlood groupsBlood componentBlood transfusion complicationtreatmentAlternatives to Blood Products
29Transfusion Therapy- 60% of transfusions occur perioperatively. - responsibility of transfusing perioperatively is with the anesthesiologist.
30Blood TransfusionUp to 30% of blood volume can be treated with crystalloids
31Blood Transfusion Why? Increase oxygen carrying capacity Restoration of red cell massCorrection of bleeding caused by platelet dysfunctionCorrection of bleeding caused by factor deficiencies
33“Transfusion Trigger”: Hgb level at which transfusion should be given. - Varies with patients and proceduresTolerance of acute anemia depends on:- Maintenance of intravascular volume- Ability to increase cardiac output- Increases in 2,3-DPG to deliver more of the carried oxygen to tissues
34Oxygen DeliveryOxygen Delivery (DO2) is the oxygen that is delivered to the tissuesDO2= COP x CaO2Cardiac Output (CO) = HR x SVOxygen Content (CaO2):- (Hgb x 1.39)O2 saturation + PaO2(0.003)- Hgb is the main determinant of oxygen content in the blood
35Oxygen Delivery (cont.) Therefore: DO2 = HR x SV x CaO2If HR or SV are unable to compensate, Hgb is the major deterimant factor in O2 deliveryHealthy patients have excellent compensatory mechanisms and can tolerate Hgb levels of 7 gm/dL.Compromised patients may require Hgb levels above 10 gm/dL.
36“Transfusion Trigger”: Hgb level at which transfusion should be given. - Varies with patients and proceduresTolerance of acute anemia depends on:- Maintenance of intravascular volume- Ability to increase cardiac output- Increases in 2,3-DPG to deliver more of the carried oxygen to tissues
37Differential Centrifugation First Centrifugation Closed SystemWhole BloodMain BagSatellite Bag1Satellite Bag2FirstPlatelet-richPlasmaRBC’s
38Differential Centrifugation Second Centrifugation Platelet-richPlasmaRBC’sSecondPlateletConcentratePlasmaRBC’s
39Blood components Prepared from Whole blood collection Whole blood is separated by differential centrifugation
40Antibodiesspecific immunoglobulin’s produced in response to an antigenic challenge.Antigen:a foreign substance that can elicit an immune (antibody) response.
41Two major antigen systems on the red blood cell are the ABO system and the Rhesus (Rh) system. Group A individuals have the A antigen present on their red blood cells.Group B individuals have the B antigen present on their red blood cells.Group AB individuals have antigens A and B present on their red blood cells.Group O have neither antigens A nor B present on their red blood cells
42Normal healthy individuals make antibodies against the A and B antigen The antibodies are found in the individual’s plasma and are referred to as naturally occurring.Group A individuals have anti B antibodiesGroup B individuals have anti A antibodiesGroup O individuals have anti A and anti B antibodiesGroup AB individuals have no antibodies
43The Rh system encompasses multiple antigens. Rh (D) negative indicates that the Rh (D) antigen is not present on the red cell
44Universal BloodBlood group O is considered the universal donor for red cells because it lacks the A and B antigen.Group O Rh negative can be considered for recipients of all blood groups.Blood group AB is considered the universal donor for platelets,
45Blood Groups Antigen on Plasma Incidence Blood Group erythrocyte Antibodies White African-A A Anti-B 40% 27%B B Anti-AAB AB None 4 4O None Anti-AAnti-BRh Rh
46Cross Match Major: Minor: Agglutination: Type Specific: - Donor’s erythrocytes incubated with recipients plasmaMinor:- Donor’s plasma incubated with recipients erythrocytesAgglutination:- Occurs if either is incompatibleType Specific:- Only ABO-Rh determined; chance of hemolytic reaction is 1:1000 with TS blood
47Type and ScreenDonated blood that has been tested for ABO/Rh antigens and screened for common antibodies(not mixed with recipient blood).- Used when usage of blood is unlikely, but needs to be available (hysterectomy).- Allows blood to available for other patients.- Chance of hemolytic reaction: 1:10,000.
48Blood components packed red blood cells (pRBC’s) platelet concentrate fresh frozen plasma (contains all clotting factors)cryoprecipitate (contains factors VIII and fibrinogen; used in Von Willebrand’s disease)albuminplasma protein fractionleukocyte poor bloodfactor VIIIantibody concentrates
49Packed Red Blood Cells 1 unit = 250 ml. Hct. = 70-80%. 1 unit pRBC’s raises Hgb 1 gm/dL.Mixed with saline: LR(lactate ringer ) has Calcium which may cause clotting if mixed with PRBC’s.
50RBC Transfusions Administration DoseUsual dose of 10 cc/kg infused over 2-4 hoursMaximum dose cc/kg can be given to hemodynamically stable patientProcedureMay need Premedication (Tylenol and/or Benadryl)Filter use—routinely leukodepletedMonitoring—VS q 15 minutes, clinical statusDo NOT mix with medicationsComplicationsRapid infusion may result in Pulmonary edemaTransfusion Reaction
51Platelet Concentrate Storage Indications Considerations Up to 5 days at 20-24°IndicationsThrombocytopenia, Plt <15,000Bleeding and Plt <50,000Invasive procedure and Plt <50,000ConsiderationsContain Leukocytes and cytokines1 unit/10 kg of body weight increases Plt count by 50,000Donor and Recipient must be ABO identical
52Plasma and FFP Contents—Coagulation Factors (1 unit/ml) Storage FFP--12 months at –18 degrees or colderIndicationsCoagulation Factor deficiency, fibrinogen replacement, DIC, liver disease, exchange transfusion, massive transfusionConsiderationsPlasma should be recipient RBC ABO compatibleIn children, should also be Rh compatibleUsual dose is 20 cc/kg to raise coagulation factors approx 20%
56Complications of Blood Therapy (cont.) Signs are easily masked by general anesthesia.Free Hgb in plasma or urineAcute renal failureDisseminated Intravascular Coagulation (DIC)
57Complications (cont.) Transmission of Viral Diseases: Hepatitis C; 1:30,000 per unitHepatitis B; 1:200,000 per unitHIV; 1:450,000-1:600,000 per unit22 day window for HIV infection and test detectionCMV may be the most common agent transmitted, but only effects immuno-compromised patientsParasitic and bacterial transmission very low
58Other Complications Decreased 2,3-DPG with storage: ? Significance Citrate: metabolism to bicarbonate; Calcium bindingMicroaggregates (platelets, leukocytes): micropore filters controversialHypothermia: warmers used to preventCoagulation disorders: massive transfusion (>10 units) may lead to dilution of platelets and factor V and VIII.DIC: uncontrolled activation of coagulation system
59Treatment of Acute Hemolytic Reactions Immediate discontinuation of blood products and send blood bags to lab.Maintenance of urine output with crystalloid infusionsAdministration of mannitol or Furosemide for diuretic effect
60Massive blood transfusion Blood volume formulaNeonate ml/kgInfants 2 years ago ml/kgAdult male ml/kgAdult female ml/kg
61Massive blood transfusion Defined one of three waysAcute administration of more than 1,5 times of estimated blood volumeThe replacement of patients blood volume by stored bank blood in less than 24 hoursThe acute administration of more than blood volume in less than 24 hours
62Massive blood transfusion Basic screening test after six-unit transfusionHemoglobin and platelets countCoagulation profile ( Pt prothrompine time , activated partial thromboplastine timePlasma fibrinogen concentrationFibrin degradation productsPH from arterial blood gas analysisPlasma Electrolyte
64Massive Blood Transfusion Coagulopathy due to dilutional thrombocytopenia. And dilution of the coagulation factorsCitrate Toxicity does not occur in most normal patients unless the transfusion rate exceeds 1 U every 5 minHypothermiaAcid–Base Balance The most consistent acid–base abnormality after massive blood transfusion is postoperative metabolic alkalosis
65Massive Blood Transfusion Serum Potassium ConcentrationThe extracellular concentration of potassium in stored blood steadily increases with time.The amount of extra-cellular potassium transfused with each unit less than 4 mEq per unit. Hyperkalemia can develop regardless of the age of the blood when transfusion rates exceed 100 mL/min.
66Massive blood transfusion Diagnosis of DICIncrease APTT , PT , fibrin degradation productDecrease platelet count , fibrinogen concentrationTreatment4 units of FFP6-8 units of plateletsCryoprecipitate if fibrinogen level less than 1 g/lPH less than 7,2 administrate 50 mmol bicarbonateRecombinant activated factor VIIa if bleeding continue in spite of use FFP platelets and cryoprecipatae
67Alternatives to Blood Products AutotransfusionBlood substitutes
68Administering Blood Products Consent necessary for elective transfusionUnit is checked by 2 people for Unit #, patient ID, expiration date, physical appearance.pRBC’s are mixed with saline solution (not LR)Products are warmed mechanically and given slowly if condition permitsClose observation of patient for signs of complicationsIf complications suspected, infusion discontinued, blood bank notified, proper steps taken.
69Administering Blood Products Consent necessary for elective transfusionUnit is checked by 2 people for Unit #, patient ID, expiration date, physical appearance.pRBC’s are mixed with saline solution (not LR)Products are warmed mechanically and given slowly if condition permitsClose observation of patient for signs of complicationsIf complications suspected, infusion discontinued, blood bank notified, proper steps taken.
70What to do? If an AHTR occurs STOP TRANSFUSIONABC’sMaintain IV access and run IVF (NS or LR)Monitor and maintain BP/pulseGive diureticObtain blood and urine for transfusion reaction workupSend remaining blood back to Blood Bank
71Blood Bank Work-up of AHTR Check paperwork to assure no errorsCheck plasma for hemoglobinRepeat crossmatchRepeat Blood group typingBlood culture
72Monitoring in AHTR Monitor patient clinical status and vital signs Monitor renal status (BUN, creatinine)Monitor coagulation status (DIC panel– PT/PTT, fibrinogen, D-dimer/FDP, Plt, Antithrombin-III)Monitor for signs of hemolysis (LDH, bili, haptoglobin)
76Pre-deposit transfusion -blood collection begins 3-5 weeks preoperatively (2-4 units store) Eliminates risk of viral transmission Reduces risk of immunological reactions Collection is expensive and time consuming Only suitable for elective surgery
77Intra-operative acute normovolemic hemodilution -1-1.5L can be collected with volume replacement -Blood stored in OR -Re-infused during or after surgery -Cheaper than pre-deposit -Little risk of clerical error -Suitable for elective surgery
78Intra-operative cell salvage -shed blood is collected from surgical field-heparin added-cells washed with saline and concentrated by centrifugation.-concentrate transfused-large volume could be used-platelets and clotting factors are consumed-suitable for cardiac surgery-contraindicated in contaminated surgical field
79Blood SubstitutesExperimental oxygen-carrying solutions: developed to decrease dependence on human blood productsMilitary battlefield usage initial goalMultiple approaches:Outdated human Hgb reconstituted in solutionGenetically engineered/bovine Hgb in solutionLiposome-encapsulated HgbPerflurocarbons
80Blood Substitutes (cont.) Potential Advantages:No cross-match requirementsLong-term shelf storageNo blood-bourne transmissionRapid restoration of oxygen delivery in traumatized patientsEasy access to product (available on ambulances, field hospitals, hospital ships)
81Blood Substitutes (cont.) Potential Disadvantages:- Undesirable hemodynamic effects:Mean arterial pressure and pulmonary artery pressure increasesShort half-life in bloodstream (24 hrs)Still in clinical trials, unproven efficacyHigh cost
82Transfusion Therapy Summary Decision to transfuse involves many factorsAvailability of component factors allows treatment of specific deficiencyRisks of transfusion must be understood and explained to patientsVigilance necessary when transfusing any blood product
85Intraoperative and postoperative interventions include Intraoperative and Postoperative Management of Blood Loss and TransfusionsIntraoperative and postoperative interventions include(A) red blood cell transfusion, (B) management of coagulopathy,and (C) monitoring and treatment of adverseeffects of transfusion.
86Recommendations from ASA 1. Monitoring for blood loss. 2. Monitoring for inadequate perfusion and oxygenation of vital organs(blood pressure, heart rate, oxygen saturation, urine output, electrocardiography). 3. Monitoring for transfusion indications (hemoglobin and hematocrit) .
87Transfusion Therapy Summary Decision to transfuse involves many factorsAvailability of component factors allows treatment of specific deficiencyRisks of transfusion must be understood and explained to patients and patient should be consentedVigilance necessary when transfusing any blood product
88Reference book and Journal reference American Society of Anesthesiologists Task Force on Perioperative Blood Transfusion and Adjuvant Therapies. Practice guidelines for perioperative blood transfusion and adjuvant therapies.