Continuous infusion of vancomycin in methicillin-resistant staphylococcus infection

The aim of the study was to verify the therapeutic response of vancomycin in methicillin-resistant staphylococcus infection (MRSA/ MRCNS) administered according to two different methods (intermittent infusion vs. continuous infusion).

Experimental plan: retrospective study; study environment: university hospital, two intensive care units. Twenty-five critically ill patients submitted to antibiotic treatment with vancomycin for infection from MRSA/MRCNS were studied. The patients, who were classified according to SAPS II scores, were divided into two groups: group A (n = 14): dose of vancomycin of 0.5 g x 4/day and group B (n = 11): dose of 2 g/day of vancomycin administered in a continuous infusion. Before the antibiotic therapy was started (T1) and prior to its end (T2), the following parameters were evaluated: degree of impairment of the main organs and systems by means of sepsis-related organ failure assessment score (SOFA) and count of the white blood cells (WBC). The length of the hospital stay during intensive care was calculated for both groups (statistics: Student t test).

No significant differences were found in the SAPS II scores and in the length of the hospital stay. In a comparison of the T1 and T2 results, we noted that patients of group A had no variations in the SOFA scores (4.84 +/- 2.48 vs. 4 +/- 3.9) and in the WBC mean values (12,415 +/- 5,099 vs. 12,841 +/- 6,864 cells/mm3). In contrast, in the patients of group B, we noted significant variations (p < 0.05) in the mean values of the SOFA scores (6.62 +/- 2.2 vs. 4.37 +/- 3.5) and in the mean values relative to the WBC count (17,242 +/- 12,842 vs. 10,757 +/- 3,610 cells/mm3).

In critically ill patients suffering from MRSA/MRCNS infection, vancomycin administration in continuous infusions improved organ function and leukocyte response, but did not seem to modify the overall evolution of the disease.