HEMATOLOGICAL EFFECTS OF POSTOPERATIVE AUTOTRANSFUSION IN SPINAL SURGERY

A prospective, randomized, controlled study was performed to determine the haematological and biochemical changes and clinical safety of pos toperative autotransfusion (Solcotrans Orthopedic Plus(R) system) in p atients undergoing spinal surgery. Fifty patients were studied and wer e randomly allocated to Control (n = 25) and Solcotrans (n = 25) group s. Both groups had their postoperatively drained blood collected into the Solcotrans reservoir but only the Solcotrans group had this salvag ed blood considered for reinfusion. After a 5-h postoperative collecti on period, analysis of the shed blood showed a haematocrit of 0.26 +/- 0.11, few platelets (80 +/- 63 10(g).l(-1)), a fibronogen level of le ss than 0.1 g.l(-1) and a high level of D-dimers. The salvaged blood d id not clot and aerobic and anaerobic culture produced no growth. The volume of blood collected was greater than 200 ml in 21 patients in th e Solcotrans group who were autotransfused (384 +/- 101 ml, range 200- 600 ml), and in 16 patients in the Control group. Within 15 min follow ing completion of reinfusion of the salvaged blood there was a signifi cant, but moderate decrease in platelet count (181 +/- 74 vs 223 +/- 9 0 10(g).l(-1), P < 0.001) and fibrinogen concentrations (2.1 +/- 0.8 v s 2.3 +/- 0.9 g.l(-1), P < 0.02), and an increase in circulating D-dim ers (P < 0.001) and plasma free haemoglobin concentrations (236 +/- 15 5 vs 82 +/- 79 mg.l(-1) P < 0.001). Prothrombin time (PT) and activate d partial thromboplastin time (APTT) did not increase, and potassium c oncentrations were not significantly affected. Because the haematocrit of shed blood was lower than that in the patients' systemic blood, th ere was no significant increase in haematocrit following reinfusion. C ultures of systemic blood following reinfusion yielded no bacterial gr owth. No side-effects were observed. There were no significant differe nces in the haematological parameters (haematocrit, platelet count, fr ee haemoglobin, APTT, PT, fibrinogen, D-dimers) between the two groups at the eighth (3 h after reinfusion) and the 24th postoperative h. No predictive factor of the volume of blood collected during the postope rative period could be identified. Postoperative autotransfusion induc ed no clinically relevant haematological effects after spinal surgery. However, since important haematological modification were found in th e shed blood, Further studies are required to determine the maximum am ount of shed blood that can be safely transfused during the postoperat ive period.