Intraoperative and postoperative effects of vancomycin administration in cardiac surgery patients: a prospective, double-blind, randomized trial.

OBJECTIVES: In response to an increased frequency of Staphylococcus epidermidis infections in postoperative cardiac surgery patients, antibiotic prophylaxis was changed to include both vancomycin and cefazolin pre- and intraoperatively. Subsequent to the addition of vancomycin prophylaxis, clinical impression and retrospective analysis supported a correlation between vancomycin administration and post-cardiopulmonary bypass norepinephrine use. DESIGN: A prospective, double-blind, randomized study. SETTING: Tertiary care center in a university hospital. PATIENTS: A total of 58 patients undergoing elective coronary artery bypass surgery under high-dose fentanyl anesthesia. INTERVENTIONS: Patients were randomized to receive cefazolin and either vancomycin or normal saline pre-, intra-, and postoperatively in a double-blinded protocol. MEASUREMENTS AND MAIN RESULTS: Hemodynamic profiles and doses of administered vasoactive agents were calculated and recorded for all patients for both intra- and postoperative time periods. Hypotension consistent with vasodilation was treated with a norepinephrine infusion. The rate and frequency of norepinephrine infusions were tabulated for both groups. Hemodynamic profiles that were obtained after the administration of the initial dose of vancomycin or normal saline and before the induction of general anesthesia and those profiles obtained after the induction of general anesthesia until the initiation of cardiopulmonary bypass showed no difference between groups and no evidence of vasodilation secondary to vancomycin administration. However, subsequent doses of vancomycin in the intra- and postoperative periods were associated with a significantly greater frequency of norepinephrine infusions to maintain normal hemodynamic indices. In the vancomycin group, 50% of patients received a norepinephrine infusion in the intra- and/or postoperative period as compared with 14% in the normal saline group (p < .01). Furthermore, the group of patients who received vancomycin and subsequently required a norepinephrine infusion had significantly lower mean systolic arterial pressure, mean arterial pressure, and systemic vascular resistance as compared with all other groups. There were no differences between groups in the use of vasopressors (other than norepinephrine) or fluid balance. CONCLUSIONS: The results show that a significantly greater number of patients who received vancomycin required a norepinephrine infusion and that, despite norepinephrine infusion therapy, systemic vascular resistance was not normalized in this group of patients. The study supports the conclusion that perioperative administration of vancomycin in cardiac surgery patients may result in hypotension requiring the use of a vasopressor in an attempt to normalize hemodynamic indices.

Production of superoxide by neutrophils.

Oxygen uptake by neutrophils has been stimulated by particulate serum-treated-zymosan (STZ) and soluble N-formylmethionyl-leucyl-phenylalanine (FMLP) in the presence and absence of the superoxide radical scavenger, cytochrome C. Results indicate that FMLP may stimulate neutrophils to produce superoxide but that STZ may not.

Systemic lupus erythematosus with a vocal cord granulomatous nodule.

Systemic lupus erythematosus (SLE) with subcutaneous granulomatous nodules, joint symptoms, and a positive latex titre for rheumatoid factor may cause diagnostic confusion with rheumatoid arthritis (RA). This has been a subject of renewed interest in recent medical literature, but reports of nodules in SLE outside the subcutis are rare. This report presents a patient with SLE and with a vocal cord granulomatous nodule, arthralgia, and a positive latex titre for rheumatoid factor. The laryngeal manifestations of SLE are discussed.

The pharmacology of hypouricemic effect of benzbromarone.

The hypouricemic effect of benzbromarone has been investigated in six subjects. Benzbromarone increased urate: creatinine by 371 per cent over control values at two to four hours after administration. Over a 24 hour period, the mean serum uric acid decreased from a control value of 7.8 +/- 0.8 to 4.3 +/- 0.6 mg/dl. This uricosuric effect was completely reversed by pyrazinamide, partially inhibited by acetylsalicyclic acid and sulfinpyrazone, and was not accompanied by an elevation of the creatinine clearance or an inhibition of urate binding to plasma protein. In vitro studies showed only 22 per cent inhibition of urate binding by benzbromarone five muM, a concentration which is transiently reached in man. Kinetic studies of human liver xanthine oxidase demonstrated non-competitive inhibition with variable hypoxanthine and a Ki slope of 8.5 muM. The Ki slopes for benzarone and allopurinol were 19.0 muM and 0.05 muM respectively. There was no elevation of the urinary oxypurines following benzbromarone ingestion. These observations suggest that only the renal tubular activity of benzbromarone is relevant to its hypouricemic effects in man. (J Rheumatol 2: 437-445, 1975).