The effect of methylprednisolone treatment on the cardiopulmonary bypass-induced systemic inflammatory response.

OBJECTIVE: Cardiac surgery with cardiopulmonary bypass (CPB) is associated with an inflammatory response caused by contact of blood with artificial surfaces of the extracorporeal circuit, ischemia-reperfusion injury, and release of endotoxin. The inflammatory reaction involves activation of complement leucocytes, and endothelial cells with secretion of cytokines, proteases, arachidonic acid metabolites, and generation of oxygen derived free radicals (OFR) by polymorphonuclear neutrophils (PMN). Although this inflammatory response to CPB often remains at subclinical levels, it can also lead to major organ dysfunction. A number of studies have demonstrated that treatment of patients with a high-dose (30 mg/kg) of corticosteroids (methylprednisolone) attenuates the CPB-induced SIR and improves the outcome of patients undergoing cardiac surgery. However, large doses of steroids can cause abnormal metabolic responses such as metabolic acidosis and hyperglycemia. In the present study, we examined the efficacy of low doses of methylprednisolone (5 and 10 mg/kg) to attenuate the CPB-induced inflammatory response, during and after heart operations. METHODS: Thirty-six adult patients undergoing cardiac surgery, were randomized into three groups: (1) control group: group A; (2) methylprednisolone, 5 mg/kg body weight: group B; and (3) methylprednisolone, 10 mg/kg body weight: group C. Plasma levels of the cytokines interleukin-6 (IL-6) and TNF-alpha were analyzed by enzyme-linked immunosorbent assay, before, during, and after CPB. OFR production was determined by cytofluorometry (FACS) at the same end points. RESULTS: No significant differences in age, body weight, CPB time, and cross-clamp time were observed among the three groups. CPB induced a marked increased in cytokine release and OFR generation. Low-dose of methylprednisolone (5 mg/kg) effectively reduced the increase in TNF-alpha and IL-6 secretion (P<0.05 compared to control group) after release of the cross-clamp. However, OFR generation was significantly reduced with a greater dose of methylprednisolone (10 mg/kg). CONCLUSIONS: The results indicate that a single low-dose of methylprednisolone (10 mg/kg) reduces the inflammatory reaction during and after CPB, by inhibition of proinflammatory cytokine release and OFR generation after release of the aortic cross-clamp.

[Systematic peroperative use of an autotransfusion system in heart surgery. A prospective and comparative study in 283 patients]. / Utilisation peropératoire systématique d'un système d'autotransfusion en chirurgie cardiaque. Etude prospective et comparative sur 283 malades.

A series of 283 patients undergoing cardiac bypass surgery was studied to determine whether intraoperative autotransfusion, haemodilution, and a change in transfusion techniques of the same surgical team could reduce homologous blood requirements. The Cell-Save Haemonetics* system was used systematically in 167 consecutive patients (Group I). This group of autotransfused patients was analysed prospectively and compared with a control group (Group II) of 116 patients operated one year before and analysed retrospectively. During the whole hospitalisation, homologous blood products were required in 40.7% of patients in Group I compared with 73.3% of patients in Group II (p less than 0.0001). The average requirements of packed cells per patient were 2.7 +/- 1.3 in Group I compared with 4.1 +/- 2.5 in Group II (p less than 0.0001). The haematocrit on discharge from the department was 29.9 +/- 4% in Group I compared with 32 +/- 4.5% in Group II (p less than 0.0001). The average volume of blood recovered by the system and then autotransfused was 620.8 +/- 242.6 ml. There was no significant difference in postoperative bleeding in the first 24 hours between the two groups. This study confirms that peroperative autotransfusion during cardiac surgery and the acceptance of a clinically well tolerated normovolumic anaemia are associated with a significant reduction in homologous blood consumption.