The clotting scores were similar with or without enoxaparin ( dialyser : 1.49 0.19 versus 1.53 0.17 , P = 0.97 ; bubble trap : 0.75 0.19 versus 0.78 0.22 , P = 0.62 ) and with the polysulphone or the HeprAN membrane ( dialyser : 1.54 0.20 versus 1.47 0.16 , P = 0.65 ; bubble trap : 0.74 0.22 versus 0.79 0.19 , P = 0.58 ) .