Postoperative Leukocytosis Trends After Durable Ventricular Assist Device Implantation

Background: Leukocytosis as a marker of inflammation is commonly seen after left ventricular assist device (LVAD) placement. Differentiating reactive postoperative leukocytosis from infection can drive antimicrobial stewardship initiatives. Methods: We conducted a retrospective chart review of adults who underwent durable LVAD implantation between 2017 and 2019 at a tertiary care hospital. We described the white blood cell (WBC) count trends postoperatively after LVAD placement. Secondary outcomes included comparing the WBC trends between patients with and without bacteremia or clinical evidence of infection requiring antimicrobial therapy. Results: We included 115 LVAD patients with a median age of 61 years. We noted a peak in median WBC count to 14.3 (×10 3 /μL) (interquartile range: 11.3, 17.6) on day 2 postoperatively and another, slightly lower peak of 14.0 between days 10 and 12. After day 12, the median WBC count declined gradually to a normal range. There were 8 (6.9%) LVAD patients with clinical or microbiological evidence of infection; postoperative WBC trends were similar when these patients were excluded. Conclusions: Postoperative leukocytosis is common after cardiopulmonary bypass, especially in LVAD patients. This expected post-LVAD leukocytosis should not prompt antimicrobial therapy without other signs of infection.