Clinical experience with polyclonal IgM-enriched immunoglobulins in a group of patients affected by sepsis after cardiac surgery.

OBJECTIVE: The purpose of this study was to evaluate the efficiency, in terms of decreasing overall mortality (primary endpoint), of an immunoglobulin M (IgM)-enriched, polyclonal intravenous immunoglobulin preparation (IVIg) (Pentaglobin; Biotest AG, Dreieich, Germany) in the treatment of a group of patients affected by sepsis after cardiac surgery. A secondary endpoint was to evaluate which subgroup, on the basis of the infectious state when the patient enrolled, could benefit the most from the treatment. Another secondary endpoint was the evaluation of an improvement in the severity score or in other variables such as Glasgow Coma Scale; arterial pressure (systolic, average, and diastolic); heart rate; central venous pressure; cardiac index; respiratory rate; PaO(2), F(I)O(2), and the ratio of PaO(2) to F(I)O(2); pH, base excess, and bicarbonate; C reactive protein and leukocytes; platelets, prothrombin time, partial thromboplastin time, fibrinogen, and anti-thrombin III; creatinine; and bilirubin.

DESIGN: Retrospective case-controlled study.

SETTING: Cardiovascular intensive care unit of a university hospital.

PARTICIPANTS: Sixty-six patients who developed sepsis in the postoperative period after cardiac surgery were admitted to the cardiovascular intensive care unit from June 1, 2001, to June 30, 2003: 30 patients (45.5%) had valvular surgery, 18 (27.5%) had myocardial revascularization, 14 (21%) had thoracic aorta surgery, and 4 (6%) had other surgery.

INTERVENTIONS: From the 66 patients diagnosed with sepsis, 22 patients (IVIg group) received IgM-enriched immunoglobulins in addition to the conventional therapy, whereas the other 44 patients (control group) were treated only with conventional therapy. The decision as to whether or not to administer the immunoglobulins was made by physicians in the intensive care unit.

MEASUREMENTS AND MAIN RESULTS: Of the 66 patients, 8 patients (3 from the IVIg group and 5 from the control group) had sepsis, 47 patients (15 from the IVIg group and 32 from the control group) had severe sepsis, and 11 patients had septic shock (4 from the IVIg group and 7 from the control group). The overall mortality rate was 31.8% without significant differences between groups (22.7% IVIg group v 36.4% control group, p = not significant). Among the 47 patients affected by severe sepsis, those from the control group had a mortality rate significantly higher than that of the IVIg group (12/32 [37.5%] v 1/15 [6.6%], p = 0.036 [2-sided Fisher exact test]). The 70-day survival rate was significantly higher in the IVIg group than in the control group (log-rank test, p < 0.04). No significant differences were found between study groups in Acute Physiology and Chronic Health Evaluation II or SOFA scores.

CONCLUSIONS: The polyclonal IgM-enriched immunoglobulins did not significantly reduce the mortality rate in the overall study population. However, in the subgroup of patients with severe sepsis, they improved the survival rate significantly.