Indications for RBC transfusion. Sima Zolfaghari MD. Pathologist 9th Annual General Surgeons Congress

Transcription

1 Indications for RBC transfusion Sima Zolfaghari MD. Pathologist 9th Annual General Surgeons Congress

2 TRANSFUSION THRESHOLDS Society guidelines Transfusion guidelines have been published by the following societies: American Society of Anesthesiology [3] British Committee for Standards in Hematology [4] Australian and New Zealand Society of Blood Transfusion [5] Eastern Association for Surgery of Trauma (EAST) and the American College of Critical Care Medicine of the Society of Critical Care Medicine (SCCM) [6] European Society of Cardiology (ESC) [7] Society of Thoracic Surgeons and the Society of Cardiovascular Anesthesiologists [8] AABB (formerly the American Association of Blood Banks) [9] American College of Physicians [18]

3 Hgb <6 g/dl Transfusion recommended except in exceptional circumstances Hgb 6 to 7 g/dl Transfusion generally likely to be indicated Hgb 7 to 8 g/dl Transfusion should be considered in postoperative surgical patients, including those with stable cardiovascular disease, after evaluating the patient s clinical status Hgb 8 to 10 g/dl Transfusion generally not indicated, but should be considered for some populations (eg, those with symptomatic anemia, ongoing bleeding, acute coronary syndrome with ischemia) Hgb >10 g/dl Transfusion generally not indicated except in exceptional circumstances

4 The Hgb level chosen is based on the results from clinical trials, but clinical judgment is required The guidelines also emphasize that the decision to transfuse should not be based only on hemoglobin level but should incorporate individual patient characteristics and symptoms. Overview of our approach Optimal transfusion practice should provide enough RBCs to maximize clinical outcomes while avoiding unnecessary transfusions.

5 Restrictive Transfusion Transfusing at a lower Hgb level; and aiming for a lower target Hgb level Liberal Transfusion Giving more blood; transfusing at a higher Hgb level For most patients, we prefer using a restrictive transfusion strategy for most hemodynamically stable medical and surgical patients, we suggest considering transfusion at a Hgb of 7 to 8 g/dl,

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8 Review of published reports identified a high- risk profile associated with increased postoperative blood transfusion. Six variables stand out as important indicators of risk: (1) advanced age, (2) low preoperative red blood cell volume (preoperative anemia or small body size), (3) pre- operative antiplatelet or antithrombotic drugs, (4) reoperative or complex procedures, (5) emergency operations, and (6) noncardiac patient comorbidities.

9 Evaluation of ABO Mismatched Transfusion in Iran from September 2009 to September 2013 Number of event per year Results : There were 2469 reported transfusion complications from 278 hospitals in four years of which 28 were ABO mismatch events. Erroneous administration was observed for 21 of 100, 000 RBC unit administered. All of these events were due to human error.(in Iran)

10 Indication of RBC 1- Acute blood loss Maintain hemoglobin > 70 g/l during active bleeding. Consider rate of bleeding, hemodynamic factors, evidence of tissue ischemia, institutional speed of blood delivery/ laboratory testing in decision about transfusion. Ensure prompt blood availability when hemoglobin is < 80 g/l Consider maintaining a higher hemoglobin level for patients with: Impaired pulmonary function Increased oxygen consumption (fever, chills) Unstable or acute coronary syndromes, Coronary artery disease Uncontrolled/unpredictable bleeding. Consider that patients with hemoglobin >100 g/l are unlikely to benefit from transfusion.

11 Anemia in critical care and coronary care Recommend a transfusion when the patient s hemoglobin is less than 70 g/l. In a patient with an acute coronary syndrome, there is controversy over where to maintain the hemoglobin level. - Consider transfusing if there are clear signs of inadequate tissue oxygen delivery in a patient with a low hemoglobin and an acute coronary syndrome. Unnecessary phlebotomy for laboratory testing is a major contributor to anemia in a critically ill patient. Except for patients with unstable coronary artery syndromes, a restrictive transfusion policy (trigger Hb 70 g/l) has proved at least as effective as a liberal transfusion policy for critically ill patients.

12 Preoperative patients Manage patients undergoing elective surgery preoperatively, intraoperatively, and postoperatively with strategies to minimize the need for RBCs. Administer RBCs one unit at a time in non-urgent settings. Assess patient prior to transfusing additional units (clinical exam and hemoglobin level). For orthopedic patients with cardiovascular disease, post operative transfusion for symptomatic anemia or hemoglobin of less than 80 g/l does not increase adverse outcomes or delay recovery compared to a transfusion trigger of 100 g/l.

13 Guideline for preoperative patients

14 Chronic Anemia Administer transfusion only when alternatives do not exist or have failed. Administer RBCs at intervals to maintain the Hb just above the lowest concentration that is not associated with symptoms or anemia. Chelation Therapy to prevent iron overload

15 Blood conservation in pereoperative setting

16 Good surgical technique Good surgical practices are highly recommended: - Assess and treat nutritional status preoperatively - Careful ligation of blood vessels - Avoid tissue trauma - Optimal use of electrocautery - Meticulous attention to surgical hemostasis - Utilize avascular tissue planes Appropriate use of topical hemostatic agents: Prevent and treat coagulopathy associated with massive transfusion

17 Iron therapy Ensure anemic patient is prescribed mg of element iron: ferrous fumarate300 mg po b.i.d Ferrous sulfate 300 mg po t.i.d Intravenous Iron Patient with iron deficiency anemia whose surgery should not be delayed to allow for oral iron therapy.

18 Consider stopping anti-platelet and anticoagulants before major surgery (1) - Primary prevention: 48 hours minimum, 7-10 days preferable - Secondary prevention (after remote MI, stroke, peripheral artery disease) low risk of bleeding procedure(e.g.,cataract surgery, plastic surgery): no need to stop ASA or clopidogrel high risk of bleeding procedure(e.g., neurosurgical procedure): 48 hours minimum, 7-10 days preferable

19 Consider stopping anti-platelet and anticoagulants before major surgery (2) Secondary prevention (high risk for arterial thrombosis recent percutaneous coronary intervention, MI, stroke OR coronary stent < 12 months) Consult patient s cardiologist or neurologist for expert advice Only stop ASA and clopidogrel if risk of bleeding exceeds risk of cardiovascular complications

20 Consider stopping anti-platelet and anticoagulants before major surgery (3) Dabigatran (PradaxTM) Consider stopping therapy 2-4 days before major surgery in patients with normal renal function In patients with renal dysfunction (creatinine clearance < 50 ml/min) consider stopping 4-5 days before major surgery Rivaroxaban (Xarelto ) Consider stopping therapy 2-3 days before major surgery in patients with normal renal function In patients with renal dysfunction (creatinine clearance < 50 ml/min) consider stopping 3-4 days before major surgery. NSAIDs Consider stopping therapy 4-7 days before major surgery Celecoxib does not inhibit platelet aggregation at usual doses

21 Minimize blood sampling and loss Restrict diagnostic phlebotomy. Use small volume tubes and testing methods. Conduct bedside microanalysis. Remove arterial and venous catheters when no longer necessary.

22 Preoperative patients on Warfarin If low risk of thromboembolic events (e.g., primary prophylaxis of atrial fibrillation): Stop warfarin 4-5 days preoperatively; repeat INR 1 day preoperatively If INR > 1.5 then give 2 mg oral vitamin K Then repeat INR preoperatively If high risk of thromboembolic events (e.g., recent deep vein thrombosis): Consider switch to unfractionated or low molecular weight heparin 4 days preoperatively; consult with hematology on timing and preferred regimen For urgent (< 6 hours) reversal of Vitamin K antagonist effect prior to surgery. Prothrombin Complex Concentrates. Vitamine K I.V

23 Acute Normovolemic Haemodilution Efficacy and Safety of ANH: did not affect the likelihood of receiving allogeneic transfusion produced a small reduction in perioperative blood loss and volume of allogeneic blood transfused. Theoretically, ANH is only of value if at least 4 units of whole blood are removed by a trained physician and total blood loss expected is > 3 L, given that the patient has: a high starting hemoglobin(>130g/l) no renal insufficiency no history o cardiovascular disease Note: Risk of transfusion-associated circulatory overload at time of re-infusion. no history of cerebrovascular disease

24 Perioperative cell salvage Which patients are eligible? With at least a 10% chance of blood exposure during elective surgery should be considered. Cardiac surgery Major vascular surgery Revision hip replacement Major spine surgery Radical prostatectomy hepatic resection Cost effectiveness

25 INTRA OPERATIVE CELL SALVAGE Principles A patient s own blood shed at the time of an operation is collected in such a way that it can be re-infused into the patient (auto-transfusion). Up to 80% of red cells can be reindication Cell salvage in orthopedic surgery (all types of salvage devices, washed and unwashed Cell salvage in cardiac surgery (unwashed only). Consider in the setting of: trauma, hepatic resection, major orthopedic and spine surgery, or ruptured aneurysm with appropriate quality assurance N Meta-analysis of 31 randomized controlled trials, including 2282 patients, in the setting of cardiac surgery found that cell salvage decreased the risk of allogeneic blood exposure.

26 INTRA OPERATIVE CELL SALVAGE Complications Complications include: Air embolism ensure air is removed prior to re-infusion Thrombocytopenia and dilutional coagulopathy Bacterial contamination (rare) Tumour dissemination in cancer surgery Hemoglobinemia ensure correct wash fluids are used and a formal maintenance program is performed on equipment

27 INTRA OPERATIVE CELL SALVAGE Contraindications - Malignant cells in operative field. - Bacterially-contaminated operative fluid, ascitic fluid, or amniotic fluid in operative field. - Use of hypotonic solutions in the operative field. - Use of topical thrombogenic agents in the operative field

28 Antifibrinolytics General Principles Antifibrinolytics are administered to prevent/ treat increased fibrinolysis during surgery, particularly cardiac surgery. I There are two types of antifibrinolytics: 1. Aprotinin a proteinase inhibitor derived from bovine lung that inhibits plasmin. 2- Tranexamic acid and aminocaproic acid inhibitors of plasminogen

29 Indications of Antifibrinolytics Antifibrinolytics in Cardiac Surgery Prophylactic administration is preferred rather than at time of marked hemorrhage. Tranexamic acid is less potent but has a better safety profile than aprotinin. DOSAGE IN CARDIAC SURGERY Tranexamic mg/kg ± 2-4 mg/kg/hr acid for duration of surgery.

30 Antifibrinolytics in Non-cardiac Surgery 2. Used in orthopedic surgery, trauma, and hepatic surgery. I Preliminary evidence suggests that antifibrinolytics reduce allogeneic blood exposure, but safety has not been fully assessed. The most recent meta-analysis included 252 RCTs that recruited over 25,000 participants. In the tranexamic acid trials, there was a significant reduction in allogeneic transfusion. The CRASH-2 study, which included over 20,000 patients (most from developing countries), provides strong evidence of benefit for low dose tranexamic acid in patients with traumatic hemorrhage (dose used: 1 g loading over 10 minutes, then infusion of 1 g over 8 hours).

31 Adverse Effects Aprotinin: hypersensitivity reactions. Reactions vary from skin flushing to severe circulatory depression; higher risk on second exposure May increase possibility of renal dysfunction in cardiac patients with, or at risk for renal disease may increase mortality Tranexamic acid: GI upset, seizures. Data from meta-analyses do not suggest an increased risk of thrombosis. Contraindications Tranexamic acid patients at elevated risk of thrombosis, pregnancy, hematuria; dose adjustment required in renal failure. Refer to product monograph for more details.

32 Other alternatives DDAVP Regional anesthesia Topical agents: Fibrin sealant Topical thrombin

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34 Massive transfusion

35 Establish unequivocal patient identification Intravenous access (2 large bore IVs) Initiate crystalloid (colloid option1). If still hemodynamically unstable after 2L, switch to RBC. Continuous clinical monitoring to assess adequate response to therapy indicated by restoration of vital signs, urine output and normalization of acid/base status Bloodwork: Group and screen, ABG, CBC, INR, Lytes, Ca, Fibrinogen Aggressive re-warming Exclude ongoing surgical bleeding (call trauma or surgical services) If within 3 hours of Traumatic injury, give Tranexamic Acid 1g IV load, then 1g IV over 8h4 Repeat INR, Fibrinogen and CBC Q60min or every half blood volume transfused

36 Criteria for MT 6 or more units PRBC in one bleeding episode with ongoing losses. 4 or more units PRBC within one hour with ongoing losses. Declare Massive Transfusion - Call the TMS with the following information: Notify Massive Transfusion Event Identify Clinical type (e.g. Trauma, GI Bleed, AAA etc) and Location (e.g. ED, OR, ICU etc) and Designate clinical contact person (provide name, local/pager to lab tech) The TMS technologist will notify other lab areas of MT (expect STAT specimens) TMS will thaw 4units plasma

37 Monitor progress Draw repeat CBC, INR, and Fibrinogen every minutes3 depending on clinical situation Send all blood work STAT Label all requests as Massive Transfusion Perform ongoing clinical assessment of response to resuscitation and/or blood products Red Cells: GOAL - Maintain hemoglobin 100 g/l Order PRBC 4 to 6 units to start Transfuse group O blood until group-specific ready (Usually min post G&S collection) Use Rh neg if possible for women <55 years old and children Switch to group specific blood ASAP (if possible, depending on blood bank inventory) Consider adjunctive hemostatic and blood conservation measures Ensure all anticoagulants have been stopped and reversed if possible (eg PCC for Warfarinized pt) Cell saver or consider autotransfusion Consider antifibrinolytic (Tranexamic Acid)

38 Monitor progress Draw repeat CBC, INR, and Fibrinogen every minutes3 depending on clinical situation Send all blood work STAT Label all requests as Massive Transfusion Perform ongoing clinical assessment of response to resuscitation and/or blood products Frozen Plasma (FP): GOAL - Maintain INR <1.5 x upper limit of range, or adequate microvascular hemostasis Initial adult dose is ml/kg, or ~4 units (random donor) Requires minutes to thaw and issue after initial four units Consider adjunctive hemostatic and blood conservation measures Ensure all anticoagulants have been stopped and reversed if possible (eg PCC for Warfarinized pt) Cell saver or consider autotransfusion Consider antifibrinolytic (Tranexamic Acid)

39 Monitor progress Draw repeat CBC, INR, and Fibrinogen every minutes3 depending on clinical situation Send all blood work STAT Label all requests as Massive Transfusion Perform ongoing clinical assessment of response to resuscitation and/or blood products Platelets: GOAL - Maintain platelet count > x 109 Adult dose is 1 platelet pool or 1 apheresis platelet unit Consider adjunctive hemostatic and blood conservation measures Ensure all anticoagulants have been stopped and reversed if possible (eg PCC for Warfarinized pt) Cell saver or consider autotransfusion Consider antifibrinolytic (Tranexamic Acid)

40 Monitor progress Draw repeat CBC, INR, and Fibrinogen every minutes3 depending on clinical situation Send all blood work STAT Label all requests as Massive Transfusion Perform ongoing clinical assessment of response to resuscitation and/or blood products Cryoprecipitate: GOAL - Maintain fibrinogen >1.0 g/l If fibrinogen <1.5 and INR >1.5 transfuse FP, consider cryoprecipitate If fibrinogen <1.5 and INR <1.5 transfuse cryoprecipitate Adult dose is 10 units (1 unit per 5 kg of body weight, to a max of 10 units per dose) Requires minutes to thaw and issue Fibrinogen replacement should be more aggressive in obstetric MT (goal >2.0) Consider adjunctive hemostatic and blood conservation measures Ensure all anticoagulants have been stopped and reversed if possible (eg PCC for Warfarinized pt) Cell saver or consider autotransfusion Consider antifibrinolytic (Tranexamic Acid)

41 Monitor progress Draw repeat CBC, INR, and Fibrinogen every minutes3depending on clinical situation Send all blood work STAT Label all requests as Massive Transfusion Perform ongoing clinical assessment of response to resuscitation and/or blood products

42 Consider adjunctive hemostatic and blood conservation measures Ensure all anticoagulants have been stopped and reversed if possible (eg PCC for Warfarinized pt) Cell saver or consider autotransfusion Consider Antifibrinolytic (Tranexamic Acid)

43 Bleeding slowed Ongoing bleeding Stop transfusion therapies when: Hemoglobin g/l INR < 1.5 Platelets > 80 x 109 Fibrinogen > 1.5 g/l Or Resolution of shock And no clinically apparent bleeding CALL TMS TO CANCEL MASSIVE TRANSFUSION STATUS Contact TMS for Pathology consult to discuss additional adjunctive therapy For Quality Assurance Lab and Clinical Area should review MT Event for deficiencies within 72 hours TMS: Transfusion Medicine Service

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