Clotting Profile by Sonoclot Analysis Is Different in Patients Undergoing Off-Pump and On-Pump Coronary-Artery Bypass Surgery

Abstract number: P0368

Paniccia¹ R, Caciolli² S, Palmarini³ MFG, Beconcini¹ S, Tellini¹ I, Pretelli³ P, Stefano² PL, Abbate¹ R, Gensini¹ GF, Prisco¹ D

¹¹Department of Medical and Surgical Critical Care, Thrombosis Centre, University of Florence; Azienda Ospedaliero-Universitaria Careggi, Florence, Italy ¹¹Department of Medical and Surgical Critical Care, Thrombosis Centre, University of Florence; Azienda Ospedaliero-Universitaria Careggi, Florence, Italy ²²UO. di Cardiochirurgia, Azienda OspedalierO-Universitaria Careggi, Firenze, Italy ³³UO Anestesia e Rianimazione 1, Azienda OspedalierO-Universitaria Careggi, Florence, Italy

The Sonoclot analyzer, a new point-of-care device, is able to assess clotting activation and platelet function after blood activation by celite. This instrument measures changes in blood viscoelastic properties by recording these variations in the form of a graph. Sonoclot ‘signatures’ show a lag period (SonACT), corresponding to ACT (sec), and a primary wave whose slope reflects the rate of fibrin formation, expressed by machine as Clot Rate (CR) and considered as an index of clot formation. Then, an inflection is produced as platelets are incorporated into the fibrin mesh and a secondary upslope leads to peak, which occurs at completion of fibrin formation. Subsequent downslope is produced as platelets induce further clot retraction. The time to peak (minutes) (TP) reflects clot retraction, and is influenced by platelet function (PF). Aim of this study was to investigate whether a different hemostatic profile at Sonoclot analysis (SIENCO Inc, USA) exists in off-pump coronary artery bypass (OPCAB) patients compared with on-pump coronary artery bypass patients (cardiopulmonary bypass – CPB – patients). Twelve OPCAB and 15 CPB patients were studied. Sonoclot analysis in OPCAB patients was performed pre and post-heparin bolus (5 min), 45 min and 75 min after heparin administration, post-protamine infusion (5 min) and 24 hours after the surgery. In CPB patients the procedure was similar to that for OPCAB patients except for extracorporeal circulation (ECC) period in which Sonoclot analysis was performed 30 and 60 min after the ECC beginning. At baseline, in OPCAB and CPB patients no difference was found for the parameters examined. After heparin, during surgery and 24 h after surgery SonACTs were significantly higher (at least P < 0.05) in CPB than in OPCAB patients. In CPB patients CR values were significantly higher after protamine infusion (P < 0.01) and 24 hours after surgery (P < 0.05) than corresponding CR values of OPCAB patients. Also TP values were significantly prolonged in CPB patients post-protamine infusion and 24 hours after surgery (P < 0.05 for both). The results of this pilot study indicate that OPCAB patients show a different profile in Sonoclot analysis in comparison with CPB patients. The clinical significance of this finding needs further studies.