**Perfusion**


#### **Blood Products**

204 Perioperative Considerations in Cardiac Surgery

Routine blood salvage with centrifugation is useful. Intra-op autotransfusion, either

Blood salvage may be considered in malignancy, as the risk may be less than that

Multidisciplinary blood management teams can limit transfusion and peri-operative

DDAVP (Desmopressin) considered if platelet dysfunction likely to respond (eg

 Identify high risk patients and utilise all available measures to conserve blood in this setting (ie. increased age, pre-op anaemia, small body size, non-CABG or urgent surgery, pre-op antithrombotic drugs, acquired/congenital clotting abnormality,

Erythropoietin (EPO) and iron to correct anaemia, or for patients at high risk of

 If possible, stop platelet P2Y12 inhibitors [thienopyridine pro-drugs (ticlopidine, clopidogrel, prasugrel), direct-acting P2Y12 inhibitors (cangrelor, ticagrelor)] and

Point-of-care testing of ADP-responsiveness may identify clopidogrel-non-

Post-CPB pump salvage with reinfusion of pump blood is reasonable. Centrifugation

Mini-CPB-circuits, vacuum-assisted venous drainage and retrograde autologous CPB

Microplegia may reduce haemodilution associated with larger volumes of crystalloid

 During CPB with moderate hypothermia, Hb≥6g/dL may be adequate, but higher transfusion trigger may be appropriate for patients at greater risk of critical non-

Open venous reservoir membrane oxygenator systems during CPB may decrease

If CPB ≥2hrs, higher and/or patient-specific heparin concentrations may reduce

Protamine titration or empiric low-dose regimen post-CPB may decrease blood loss

multiple comorbidities, thrombocytopenia or abnormal platelet function)

Lysine analogues (E-aminocaproic acid, tranexamic acid) reduce blood loss.

If allogenic transfusion required, use leukodepleted red blood cells.

**General Measures for Blood Conservation** 

direct or following centrifugation is useful

associated with allogenic blood transfusion.

bleeding whilst maintaining safe outcomes. Minimise volume taken for blood sampling

uraemia, type I von Willebrand's Disease)

delay surgery until effect has subsided

responders who do not require delay

Risk/benefit ratio does not favour aprotinin use in adults

is reasonable. Modified ultrafiltration is indicated.

consumption of platelets and coagulation factors

circuit priming may reduce transfusion requirements.

Consider FIX in Haemophilia B

developing anaemia

cardioplegia solution

cardiac end-organ ischaemia

blood loss and improve safety

**Pre-op Measures** 

**Intra-op Measures** 

**Medical** 

**Perfusion** 

Do not transfuse if Hb≥10g/dL unless specifically indicated

Non-red cell haemostatic products ideally guided by point-of-care tests


#### **Surgical**


### **Post-op Measures**


Choice of fluid for intravascular volume replacement can also affect coagulation. Colloidal plasma substitutes may interfere with haemostasis in non-specific or specific ways. Nonspecific effects relate to haemodilution, with decreased circulating concentrations of coagulation factors, platelets and red blood cells. Specific effects are discussed by colloid type.

Albumin inhibits platelet aggregation directly (56), and may affect fibrin polymerisation, but in vitro is considered not to affect haemostasis (57).

Dextrans are not widely used due to potential allergic, renal and haemostatic side effects. They cause platelet dysfunction by decreasing vWF, possibly by adsorption. Dextrans also accelerate activation of fibrinogen, facilitate fibrinolysis, and may coat endothelium and platelets thus decreasing platelet adhesion.

Gelatins can impair platelet coagulation (58) and decrease vWF, but are generally accepted not to influence perioperative bleeding (57).

Hydroxyethyl starches (HES) induce platelet dysfunction through effects on GPIIb-IIIa expression and on vWF and FVIII levels. HES can also favour fibrinolysis. Haemorrhagic complications have been reported more frequently with high molecular weight (Mw) HES than with lower Mw.

Use of colloids outside the context of clinical studies has recently been questioned as well (59). When using crystalloid alternatives, a balanced salt solution may offer less disruption of haemostasis than saline, possibly due to maintenance of plasma calcium concentrations.
