Fluconazole exposure during mechanical circulatory support (MCS) device insertion

Mechanical circulatory support (MCS) devices are an important intervention for patients with advanced heart failure. Invasive Candida spp. infections following MCS device insertion have been reported. The addition of fluconazole to surgical prophylaxis regimens is controversial, and there is a lack of data describing exposures achieved during MCS device insertion.

A pilot pharmacokinetic study was undertaken to determine the plasma fluconazole exposure achieved during MCS device insertion. Perioperative fluconazole levels were drawn at four time points during the MCS device insertion surgery: knife to skin, start of cardiac bypass, end of cardiac bypass, and at the time of skin closure. A secondary outcome was to determine the Candida spp. colonization patterns in this patient cohort.

Forty perioperative plasma fluconazole concentrations (from 10 patients) were available for analysis. One patient received 400 mg IV fluconazole preoperatively, and the remainder received 200 mg IV. The median measured concentration at knife to skin, start of cardiac bypass, end of cardiac bypass, and skin closure, was 3.85 mg/L (IQR: 3.53-4.48 mg/L), 3.75 mg/L (IQR: 3.45-4.23 mg/L), 3.45 mg/L (IQR: 3.08-3.75 mg/L), and 3.35 mg/L (IQR: 2.93-3.55 mg/L), respectively. Preoperative Candida colonization swabs isolated Candida parapsilosis (n = 2), Candida glabrata (n = 2), and Candida albicans (n = 1). A single postoperative swab was positive for C. glabrata.

In 10 patients undergoing MCS device insertion, fluconazole 200 to 400 mg IV achieved median plasma levels of between 3 and 4 mg/L throughout the surgical procedure but may not adequately cover for C. glabrata.