Italian Clinical Evidences during Surgical Corrections of Congenital Heart Defects in Extracorporeal Circulation

Objective: We reviewed with an observative, nonrandomized, multicentre study, the conduction method of the cardiopulmonary bypass (CPB) during surgical corrections of congenital heart defects in terms of : 1) verify whole organ perfusion adequacy, during the CPB, and particularly the renal perfusion (following the R.I.F.L.E. classification) and related to: Blood flow from HLM (Heart Lung Machine), Hemoglobin level present in the blood and temperature of the patient (normothermia and hypothermia). 2) Investigation on the “prime” quality in terms of hemoglobin concentration, analyzing the possibility of a crystalloid prime volume in relation to the weight and blood volume of patient. Materials and Methods: Between July 2010 and December 2010 in 10 Italian pediatric cardiac hospitals we observed the CPB conduction in 70 pediatric patients. Enrolled patients in this study must satisfy the following criteria: Group A1: weight ≤ 5Kg; Group A2: weight from 5 to10 Kg; Group B: weight from 10 to 20 Kg. All blood parameters are monitored 5 times: T0- Base value; T1- 5 minutes after the start of CPB; T2- 5 minutes after the end of CPB; T3- arrive ICU unit; T4- 24 hours after surgery. During CPB the parameters are monitored by the emogas-analyzer “on line” CDI500 Terumo (Terumo, Ann Arbour, USA). The parameters evaluation is updated and shown on the monitor every 6 seconds. This high performance allows a complete and continuous vision on the perfusion quality and also a fast “reaction time” for the correction of the blood parameters when they aren‟t within the best values. The CDI500 monitoring system reports the following parameters: pH, PCO2, PO2, HCO3, BE, SVO2; SAO2, K+, Hct, Hgb, Qb, VO2, temp. Results: Data analysis show significant differences for three groups A1(3.75±0.56 Kg), A2(7.2±0.53 Kg), B(14.6±3.1Kg) and their interaction (p ‹0.005). Major differences were observed in effective priming volume (A1: 230±22ml; A2: 369±88ml; B: 527±55ml), diuresis (A1: 60±10ml; A2: 77±43ml; B: 226±44ml), use of RBC units (A1: 300±30ml; A2: 264±50ml; B: 363±125ml) and hemoglobin level in different T and especially: A1 group T0- T1(p<0,000001) and T2-T3(p<0,000001); A2 group T1-T2(p<0,000001) and T2- T3(p<0,00005); B group T0-T1(p<0,005) and T2-T3 (p<0,00005). Regarding platelets depletion, significant statistical differences were observed at 5 minutes after end of CPB: The study data are collected by DATA TRIAL Form and SOFTWARE PROGRAMME of DATA TRIAL; (Parca/Ghitti system, Italy). The statistical significances are been evaluated by the ANOVA. 24 group A1(p<0,000005) group A2(p<0,000005) group B(p<0,000001) and at 24 hours after surgery: group A1(p<0,0005) group A2(p<0,0001) group B (p<0,000001). Conclusion: Besides the scientific community confirms that the mortality and morbidity risk is associated to several factors (Aristotle score) and the reduction of the post-operative renal insufficiency (R.I.F.L.E. score) is directly proportional to the mortality index, during the CPB is possible the preservation of the renal function maintaining an appropriated organ perfusion in terms of blood flow and hemoglobin level relating them to the patient temperature. An exiguous perfusion blood flow and low hemoglobin level may expose small patients to post-operative renal insufficiency. In the initial Italian experience, we have seen that the high quality of CPB associated with innovative techniques and tools as constantly monitor the blood parameters are very important to help perfusionists to maintain high quality standards during CPB.