Some characteristics of blood shed into the Solcotrans postoperative orthopaedic drainage/reinfusion system.

OBJECTIVE

To assess the suitability of blood shed into the Solcotrans orthopaedic autotransfusion system as a source of autologous blood for transfusion.

DESIGN

Blood samples were taken from patients after surgery and from shed blood within the Solcotrans units.

SETTING

Surgery was performed at a public hospital.

PATIENTS

All six patients underwent total knee replacements.

MAIN OUTCOME MEASURES

Measurements were made of haemoglobin, haematocrit, platelets, pH, potassium, plasma haemoglobin, fibrinogen, D-dimer, plasminogen activator, thromboplastin and fibrinopeptide A. The non-activated partial thromboplastin time was estimated. Shed blood was compared with homologous whole blood to assess the thrombogenic potential of shed blood in vitro.

RESULTS

The haemoglobin and haematocrit levels of the shed blood were significantly lower than venous blood (P = 0.008). Levels of potassium in shed blood were normal although there was significant haemolysis. Shed blood was depleted of clotting factors, with increased levels of D-dimer (16-128 g/L). Activation of the coagulation pathway within the shed blood was shown by a shortened non-activated partial thromboplastin time (90-120 s), and detectable levels of thromboplastin. Propionibacterium acnes was isolated from one of the units.

CONCLUSION

Reinfusion of large volumes of shed blood should probably be avoided, but use of the Solcotrans orthopaedic transfusion system in conjunction with other autologous transfusion practices can reduce the patient's requirement for homologous blood.