Updated: 2/23/2020

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
          • heartburn
          • abdominal pain
      • folate and vitamin B12 supplementation
        • are essential vitamins for DNA synthesis that is necessary for erythropoiesis
      • anemia-associated vitamin supplemenation
        • iron 256 mg/day, vitamin C 1 g/day, and folate 5 mg/day for 30-45 days preopeative 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 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
        • preoperative Hb < 13g/dL
        • low body weight (< 50 kg)
        • surgies when considerable blood loss is expected
      • 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 Hb levels
      • 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
      • 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 performed with sufficient time prior to procedure
    • 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 Hb 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 the preoperative autologus blood transfusion
    • not commonly performed due to increased time in OR and labor associated 
  • Tourniquet
    • allows for a dry surgical field and better cement interdigitation during arthroplasty cases
    • minimum inflation pressure of 100 -150 mm Hg of systolic pressure
      • 200 - 250 mm Hg in upper extremity
      • 300 - 350 mm Hg in lower extremity
      • use of esmarch bandage to exsanguinate limb prior to tourniquet inflation
        • avoid in infections and tumor cases
          • elevate limb for 2 to 3 minutes prior to inflating tourniquet
    • in total knee arthroplasty, tourniquet use has been associated with shorter surgical time, but increased thromboembolic events
    • increased postoperative wound complications requiring revision surgery with delayed tourniquet release in total knee arthroplasty
      • attributed to increased lateral retinacular releases due to patellar tracking assessed with tourniquet inflated
    • avoid use longer than 2 hours
      • time for tissue equilibrium after use
        • 5 minutes after 90 minutes
        • 15 minutes after 3 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
    • platlet-rich plasma 
      • centrifugation of patient's blood to isolate plasma with high contents of platlets, growth factors, and clotting factors
      • proposed benefit of improved hemostasis, wound healing and recovery
    • platlet-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 as 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 of 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 
    • shed 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
      • below 13 g/dL more likely
    • other risk factors
      • female gender
      • increased age
      • larger patient size
      • longer procedures
      • lateral releases in total knee arthroplasty
    • 1 unit increased Hb by 1 g/dL
    • no absolute criteria for transfusion
      • transfusion should be considered for anyone with Hb <6 g/dL
      • transfusion should be considered for postoperative patients with Hb 7-8 g/dL
      • routine transfusion should be avoided for Hb > 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
      • Hb levels between 6 to 8 g/dL should be based on patient factors
        • expectation of continued blood loss
        • intravascular volume status
        • cardiovascular reserve
        • response to anemia
  • Allogenic platlet 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
      • platlet count below 5,000/mm^3
        • give platlets to avoid spontaneous bleeding
      • platlet count below 50,000/mm^3
        • give platlets before surgery
      • platley count above 100,000/mm^3
        • no need to transfuse
  • Postoperative iron supplementation
    • daily oral iron replacement mild acute blood loss anemia
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 the use of these agents 
 

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