What is the objectives for RBC administration
The proper objective for RBC transfusion is the improvement of inadequate oxygen delivery
Define class I, II, III, and IV hemorrhages
I- a loss of 15% of total blood volume
II-a loss of 15%-30% of blood volume
III-a loss of 30%-40% of blood volume
IV-a loss of more than 40% of blood volume
What are signs and symptoms of class I, II, III and IV
I-usually has little hemodynamic effect other than vasoconstriction and mild tachycardia
II-produces tachycardia and a decrease pulse pressure; unanesthetized patients may also experience anxiety or restlessness.
III-produces signs of hypovolemia, marked tachycardia, tachypnea, and systolic hypotension; unanesthetized patients demonstrate altered mental status
IV-is life threatening and accompanied by marked tachycardia and hypotension, very narrow pulse pressure, and low urine output; mental status is markedly depressed.
What are the risks of diminished oxygen-carrying
serious clinical implications, primarily due to ischemic effects on the myocardium and brain.
How is oxygen carrying capacity defined
Oxygen delivery (Do2) is defined as the product of cardiac output (Qt) and arterial oxygen content (Cao2).
?(Cao2) is a function of hemoglobin concentration (Hb), and the amount of oxygen physically dissolved in arterial blood.
￼￼￼￼￼￼￼Do2 = (CaO2) (Qt),
Cao2 = (SaO2/100) (1.39x Hb) + (0.003 PaO2)
Define differences between acute and chronic
Chronic anemia is better tolerated than acute anemia.
In adults with chronic anemia, cardiac output usually does not change until the hemoglobin concentration falls below 7g/dl. Significant symptoms are unusual unless the RBC mass is decreased by 50%
In acute anemia, reductions in arterial oxygen content usually are well tolerated because of compensatory increases in cardiac output.
What are the recommendations for RBC
1. Transfusion is rarely indicated when the hemoglobin concentration is greater than 10g/dl, and is almost always indicated when it is less than 6g/dl, especially when the anemia is acute.
2. The determination of whether intermediate hemoglobin concentrations (6-10g/dl) justify or require RBC transfusion should be based on the patient's risk for complications of inadequate oxygenation.
3. The use of a single transfusion "trigger" (ei 10/30 rule) for all patients is not recommended.
4.When appropriate, preoperative autologous blood donation, intraoperative and postoperative blood recovery, acute normovolemic hemodilution, and measures to decrease blood loss (deliberate hypotension and pharmacologic agents) may be beneficial.
5. The indications for autologous RBCs may be more liberal than allogenic RBCs because of the lower (but still significant) risk associated with autologous transfusions.
What are the risks/adverse reactions associated with
￼￼￼￼￼Transfusion reactions, often manifested in awake patients by fever, chills, or urticaria, are the most common adverse reaction of transfusion with RBC's.
These signs may not be detectable during anesthesia.
￼Nonhemolytic transfusion reactions occur in approximately 1-5% of all transfusions.
The estimated risk of ABO-incompatible transfusion is 1:33,000 RBC transfusions
￼The probability of a fatal hemolytic transfusion reaction is uncertain, with estimates of 1:500,000 to 1:800,000.
￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼Infectious disease- The incidence of post transfusion hepatitis, more than 90% due to hepatitis C has decreased since the introduction of testing for the virus.
The reported incidence of hepatitis C seroconversion is 0.03% per unit transfused, however the actual incidence is thought to be lower.
The risk of transmission of hepatitis B is estimated to be 1:200,000
The current risk of HIV in the US is 1:450,000- 1:600,000 per transfused unit of blood.
Perhaps the most common viral agent transmitted by blood transfusion is cytomegalovirus, most infections are subclinical.
Parasitic and bacterial agents can be transmitted by
blood, but the incidence of clinically significant disease ￼￼￼￼in the US is low, possibly 1:1,000,000 units blood.
What is HELLP syndrome?
What are the recommendations for Platelet
Prophylactic platelet transfusion are ineffective and rarely indicated when thrombocytopenia is due to platelet destruction (e.g. idiopathic thrombocytopenic purpura).
2. Prophylactic platelet transfusion is rarely indicated in surgical patients with thrombocytopenia due to decreased platelet production when the platelet count is greater than 100,000, and is usually indicated when less than 50,000. The determination of whether patients with intermediate (50,000-100,000) require therapy should be based on the risk of
￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼3. Surgical and obstetric patients with microvascular bleeding usually require platelet transfusions if the platelet count is less than 50,000, and rarely require transfusion if platelet count is greater than 100,000. With intermediate thrombocytopenia (50,000-100,000) the determination should be based on the risk of more significant bleeding.
￼￼4. Vaginal deliveries or operative procedures associated with insignificant blood loss may be undertaken with platelet counts less than
￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼￼5. Platelet transfusions may be indicated despite an apparently adequate platelet count if there is known platelet dysfunction and microvascular bleeding.
What are the recommendations for FFP transfusion
FFP is indicated for urgent reversal of warfarin therapy.
2. For correction of known coagulation factor deficiencies for which specific concentrations are unavailable.
3. For correction of microvascular bleeding in the presence of elevated (>1.5 times normal) PT or PTT.
4. For correction of microvascular bleeding secondary to coagulation factor deficiency in patients transfused with more than one blood volume when PT and PTT cannot be obtained in a timely fashion.
Recommendations for FFP cont...
5. FFP should be given in doses calculated to achieve a minimum of 30% of plasma concentration (10-15ml/kg of FFP), except for urgent reversal of warfarin anticoagulation, for which (5-8ml/kg of FFP) will usually suffice. 4-5 platelet concentrations, or one unit of whole blood provide a quantity of coagulation factors similar to that contained in one unit of FFP (except for decreased, but still hemostatic concentrations of factors V and VIII in whole blood).
6. FFP is contraindicated for augmentation of plasma volume or albumin concentration.
What are the components of cryoprecipitate
Cryoprecipitate contains factors VIII, fibrinogen, fibronectin, von Willibrand's factor, and factor XIII, is used for correction of inherited and acquired coagulopathies.
What are the recommendations for
1.Prophylaxis in nonbleeding perioperative or peripartum patients with congenital fibrinogen deficiencies or von Willibrand's disease unresponsive to DDAVP.
2. Bleeding patients with von Willibrand's disease.
3. Correction of microvascular bleeding in massively transfused patients with fibrinogen concentrations less than 80- 100mg/dl (or when fibrinogen concentrations cannot be measured in a timely fashion).
What are indications for albumin
Albumin is indicated for plasma volume expansion and maintenance of cardiac output in the treatment of certain types of shock; may be useful for burn patients, ARDS, and cardiopulmonary bypass.
What are indications for plasma protein fraction?
PPF 5% is administered to treat hypovolemic shock.
What are some indications for IVIG
Idiopathic thrombocytopenia purpura
Used along with appropriate antiviral and antibiotic therapy in patients immunodepression (CLL)
What agents are used as blood volume
Hydroxyehyl Starch (Hetastarch) or Hespan® is a complex polysaccharide that is available in a 6% solution for intravascular volume expansion.
Hetastarch and albumin expand intravascular fluid volume equally.
What are advantages of hetastarch compared
Advantages of hetastarch include; oncotic properties, long duration of hemodynamic effects, low incidence of anaphylactoid reactions, the absence of disease transmission, and low cost compared to albumin.
What are adverse reactions associated with
Serum microamylasemia may follow administration of hetastarch
Prolongation of PTT and a decrease in the
plasma concentrations of factor VIII, von Willibrand's factor, and fibrinogen, plus decreased platelet function.
Therefore maximum safe dosage 20ml/kg/day up to 1500ml/day
What is dextran indications?
A special solution of dextran (32% dextran- 70) is used in hysteroscopy to help distend and irrigate the uterine cavity and decrease the likelihood of adhesions after reconstructive tubal surgery for infertility
Low molecular weight dextran injected comcomitantly with epinephrine slows intravascular absorption of the catecholamine.
Likewise, intercostal nerve blocks performed with LMD and bupivicaine provide postoperaitve analgesia lasting an average 40 hours compared to < 12 with bupivicaine alone
What are adverse reactions associated with
Increased bleeding time
Noncardiac pulmonary edema