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Updated: 6/18/2021

Operative Blood Loss & Transfusion

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  • Preoperative Management
    • Aimed at optimizing patient hemoglobin levels to allow for better patient stress tolerance at the time of surgery
      • vitamin supplementation
        • iron
          • major building block of hemoglobin and functions to bind oxygen in the porphyrin ring structure
          • supplementation provides material for hemoglobin synthesis
          • some studies have demonstrated a significant decrease in postoperative transfusions in patients with anemia-reducing vitamins
          • increased side effects
            • constipation
            • acid reflux/heartburn
            • abdominal pain
        • folate and vitamin B12 supplementation
          • are essential vitamins for DNA synthesis that are necessary for erythropoiesis
        • anemia-associated vitamin supplementation
          • iron 256 mg/day, vitamin C 1 g/day, and folate 5 mg/day for 30-45 days preoperatively have been associated with decreased transfusion rates
            • should only be used in patients with specific deficiency
      • erythropoietin (EPO)
        • recombinant protein of natural glycoprotein produced by renal pericapillary cells
          • signals bone marrow cells to stimulate red blood cell (RBC) production
        • studies have demonstrated greater efficacy than preoperative autologus blood donation and reinfusion systems
        • high cost associated with use
          • treatment cost equivalent to 4 units of allogenic blood transfusion
        • recommended for high risk patients (e.g. low preoperative hemoglobin, surgeries with significant blood loss anticipated, etc.)
        • three dosing regimens have been proposed:
          • 600 IU/kg - 4 doses: preoperative days 21, 14, 7, and 0
          • 300 IU/kg - 15 doses: preoperative day 10 to postoperative day 4
          • 150 IU/kg - 9 doses: preoperative day 5 to postoperative day 3
      • preoperative autologous blood donation
        • preoperative procurement of 1 to 2 units of autologous blood
        • performed at least 3 weeks from the planned surgery to allow for recovery of hemoglobin levels
        • may be of benefit in patients with normal Hb (>14 g/dL) ubdergoing procedures with high expected blood loss
          • may be performed in any patient with Hb > 11 g/dL and body weight >50 kg with sufficient time prior to procedure
        • current literature does not seem to support efficacy and cost effectiveness in the management of postoperative anemia
          • concerns that there is a high incidence of unused units
      • preoperative embolization
        • standard treatment for oncology cases with highly vascular tumors
          • renal cell carcinoma
        • performed within 24 hours of the procedure
    • Preoperative labs
      • CBC
        • evaluate hemoglobin levels
        • determine mean corpuscular volume
          • microcytic anemia suggests iron deficiency
          • macrocytic anemia suggests folate and vitamin B12 deficiency
      • folate
      • B12
  • Intraoperative Management
    • Acute normovolemic hemodilution
      • autologus blood harvested right before or at the time of surgery
        • removed volume is replaced with colloid
      • extracted blood is transfused in the perioperative period
      • requires less planning than preoperative autologus blood transfusion
      • not commonly performed due to increased time in OR and associated labor
    • Tourniquet
      • allows for a dry surgical field and better theoretical cement interdigitation during arthroplasty cases
      • minimum inflation pressure of 100 -150 mm Hg of systolic pressure
        • may use of esmarch bandage to exsanguinate limb prior to inflating tourniquet
          • avoid in infections and tumor cases
        • may also elevate limb for gravity exsanguination prior to inflating tourniquet
      • avoid use longer than 2 hours
      • tourniquets should be cautiously used in patients with severe peripheral vascular disease
        • risk of arterial complications associated with:
          • history of arterial insufficiency
          • absence of pedal pulses
          • suspected popliteal aneurysm
          • radiographic arterial calcifications
        • preoperative vascular surgery consultation in high risk patients
    • Tranexamic acid (TXA)
      • lysine derivative that competitively blocks plasmin binding sites on fibrin
        • results in a decrease in fibrinolysis and stabilized clot formation
      • multiple studies have demonstrated a significant reduction in operative blood loss and transfusion rates with perioperative administration
        • no increased risk of DVT and PE
        • does not alter PT and PTT times
      • multiple dosing regimens and routes of administration utilized
        • IV, oral, and topical all appear equally efficacious
      • contraindications
        • history of CVA
        • allergy
        • severe CAD
      • side effects
        • seizures
          • binds to glycine and GABA channels leading to a reduced seizure threshold
    • Aminocaproic acid
      • lysine derivative that competitively inhibits plasmin
        • results in decreased fibrinolysis
      • studies have demonstrated decreased blood loss with aminocaproic acid in arthroplasty
      • lower cost than TXA
      • does not decrease seizure threshold
    • Topical hemostatic agents
      • collagen agents
        • stimulate the instrinsic pathway of coagulation cascade to promote hemostasis
        • microfibrillar collagen
          • dry, fine, white powder
          • must be applied with dry surgical instruments to a dry field
      • fibrin sealant
        • consists of two seperate mixtures
          • one contains fibrin and factor XIII
          • one contains thrombin and calcium
        • combining the mixtures creates a fibrin seal where it is sprayed
      • platelet-rich plasma
        • centrifugation of patient's blood to isolate plasma with high contents of platelets, growth factors, and clotting factors
        • proposed benefit of improved hemostasis, wound healing and recovery
      • platelet-poor plasma
        • isolated from centrifugation process
        • combined with thrombin and calcium to provide an autologous fibrin sealant
      • gelfoam sponges
        • manufactured from animal-skin gelatin and processed into sponge-form
        • isolated use exerts mostly mechanical hemostasis against low-pressure bleeders
        • can be soaked with thrombin, which can act as a scaffold for the coagulation cascade
        • excess gelfoam should be removed as it may interfere with bone healing
      • topical hemostatic agents do not appear to be cost-effective in total joint arthroplasty cases
        • beneficial in spine surgery to promote hemostasis without inflicting harm to adjacent neural structures
      • topical TXA
        • typically administered near the end of the procedure to control postoperative bleeding
        • decreases fibrinolysis and stabilizes clot formation
        • may be an alternative route of adminstration in patients with higher risk of complications
          • history of MI, CAD, or CVA
      • gelatin-thrombin matrix
        • commonly used in spine surgery to control epidural bleeding
          • brand names include Floseal and Surgiflo
        • consists of porcine or bovine gelatine matrix combined with human derived thrombin
        • acts at the end stage of the coagulation cascade leading to fibrin formation
    • Reinfusion systems (cell saver)
      • recycles intraoperative blood loss for later transfusion
        • can be transfused intraoperatively during longer procedure
      • collected blood is filtered, washed, and transfused within 6 to 8 hours from the procedure
        • serves as an alternative to allogenic blood transfusion
        • theoretical benefits of minimizing wound complications and hematoma formation
      • complications
        • coagulopathy
          • altered composition of the transfused blood containing elevated fibrin split products and inflammatory cytokines (TNF-α and interleukins)
            • especially problematic in unwashed systems
          • can lead to increased wound drainage
        • contamination
        • cost
  • Postoperative Management
    • Allogenic blood transfusion
      • preoperative hemoglobin strongest risk factor for postoperative blood transfusion
      • other risk factors
        • female gender
        • increased age
        • larger patient size
        • longer procedures
        • lateral releases in total knee arthroplasty
      • 1 unit of packed red blood cells generally increases hemoglobin by 1 g/dL
      • no absolute criteria for transfusion
        • transfusion should especially be considered at hemoglobin <8 g/dL
        • routine transfusion should be avoided for hemoglobin > 8 g/dL
          • no increased mortality has been seen with this criteria, even in patients with cardiac history
          • initiate transfusion if patient is symptomatic
            • orthostatic hypotension
            • tachycardia unresponsive to fluids
    • Allogenic platelet transfusion
      • blood product most likely to be contaminated
        • stored at room temperature
        • infections in 10 cases per million units transfused
        • gram positive organisms most common
      • thrombocytopenia
        • platelet count below 5,000/mm^3
          • give platelets to avoid spontaneous bleeding
        • platelet count below 50,000/mm^3
          • give platelets before surgery
        • platelet count below 100,000/mm^3
          • consider giving platelets before surgery
        • platelet count above 100,000/mm^3
          • no need to transfuse
    • Postoperative iron supplementation
      • daily oral iron supplementation for mild acute blood loss anemia related to surgery
  • Special Consideration
    • Jehovah's Witness (JW)
      • hold beliefs that blood transfusions are forbidden by the Bible
        • some patients may still consent to a blood transfusion
        • some patients may consider the use of cell saver as an alternative to allogenic blood transfusion
      • use of colloids and coagulation factors are not forbidden and a matter of personal choice
      • bovine-derived hemostatic agents are generally approved by JW
        • products derived from human plasma are a personal decision of JW
          • preoperative discussion about the use of any special agents
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