Intraoperative blood salvage devices allowing a reinfusion of red blood cells (RBCs) after processing of shed blood and stagnant blood in the mediastinal cavity are more and more used to reduce homologous blood requirements in cardiac surgery with cardiopulmonary bypass (CPB). As the proinflammatory activity of the shed blood also contributes to morbidity during CPB, we conducted a prospective study in order to examine the quality of autologous blood before and after processing with five different devices [BRAT2, Sequestra, Compact Advanced, Cell Saver 5 (CS5), Continuous Autologous Transfusion System (CATS)]. All systems resulted in an excellent haemoconcentration, ranging from 53.7% (Compact) to 68.9% (CATS). The concentrations and elimination rates of several inflammatory markers [IL-1beta, IL-2, IL-8, TNFalpha, myeloperoxidase (MPO), elastase] were examined. Except for the Sequestra, an important increase in concentration of IL-1beta (between 30% and 220%) has been observed after processing with each device. In contrast, the attenuation rate of IL-6 and TNFalpha (95%) was optimal for all investigated blood salvages systems. Regarding IL-8, only the CATS and CS5 systems were able to attenuate this biological parameter with an excellent efficacy. The rate of attenuation in MPO and elastase, as markers of leukocyte activation, was higher than 80% for all devices. In conclusion, the different RBC washing systems tested in this study resulted in a significant attenuation of the inflammatory response. Increased levels of IL-1beta after processing remained, however, unclear. According to the type of protocol, based on inlet haematocrit, fill and wash speeds, and wash volumes, small variations in reducing the inflammatory response have been observed from one device to another.

Low flow extracorporeal veno‐venous CO2 removal (ECCO2R) therapy is used to remove CO2 while reducing ventilation intensity. However, the use of this technique is limited because efficiency of CO2 removal and potential beneficial effects on pulmonary hemodynamics are not precisely established. Moreover, this technique requires anticoagulation that may induce severe complications in critically ill patients. Therefore, our study aimed at determining precise efficiency of CO2 extraction and its effects on right ventricular (RV) afterload, and comparing regional anticoagulation with citrate to systemic heparin anticoagulation during ECCO2R. This study was performed in an experimental model of severe hypercapnic acidosis performed in two groups of three pigs. In the first group (heparin group), pigs were anticoagulated with a standard protocol of unfractionated heparin while citrate was used for ECCO2R device anticoagulation in the second group (citrate group). After sedation, analgesia and endotracheal intubation, pigs were connected to a volume‐cycled ventilator. Severe hypercapnic acidosis was obtained by reducing tidal volume by 60%. ECCO2R was started in both groups when arterial pH was lower than 7.2. Pump Assisted Lung Protection (PALP, Maquet, Rastatt, Germany) system was used to remove CO2. CO2 extraction, arterial pH, PaCO2 as well as systemic and pulmonary hemodynamic were continuously followed. Mean arterial pH was normalized to 7.37 ± 1.4 at an extracorporeal blood flow of 400 mL/min, coming from 7.11 ± 1.3. RV end‐systolic pressure increased by over 30% during acute hypercapnic acidosis and was normalized in parallel with CO2 removal. CO2 extraction was not significantly increased in citrate group as compared to heparin group. Mean ionized calcium and MAP were significantly lower in the citrate group than in the heparin group during ECCO2R (1.03 ± 0.20 vs. 1.33 ± 0.19 and 57 ± 14 vs. 68 ± 15 mm Hg, respectively). ECCO2R was highly efficient to normalize pH and PaCO2 and to reduce RV afterload resulting from hypercapnic acidosis. Regional anticoagulation with citrate solution was as effective as standard heparin anticoagulation but did not improve CO2 removal and lead to more hypocalcemia and hypotension.

No abstract

The distal extension of ascending aorta pathology often requires prosthetic grafting into the proximal arch. In order to perform optimal distal anastomosis, an open technique under a short period of circulatory arrest (CA) was adopted. For this purpose we evaluated prospectively a simplified technique for surgery and perfusion. The aneurysmal aorta was directly cannulated to cool down the patient to 26 degrees C. Under CA and retrograde cerebral perfusion, the diseased aorta and aortic cannulation site were resected. After completion of the distal anastomosis, antegrade rewarming was performed via recannulation of the AAo graft (side branch graft) whilst surgery was proceeded on the root and/or aortic valve. This technique clearly addresses the safety of cannulation into the aneurismal aorta. The issues of cerebral and visceral protection during CA and antegrade reperfusion and rewarming have been analysed prospectively in eight patients operated on over a period of 6 months. Our preliminary results indicate that this technique of arterial cannulation and CA at 26 degrees C for the management of degenerative AAo disease involving the proximal arch appears safe both in terms of cerebral and systemic (visceral, muscular) protection. By this way, the complications related to deep hypothermia and prolonged cardiopulmonary bypass are avoided. This assumption may be only valid for a CA period less than 30 min. This preliminary study is limited by its small size and heterogeneity of the pathologies. However, the simplicity, surgical ease, rapidity and efficacy conveyed by this technique warrant further consideration and evaluation.