Delayed febrile response with blood stream infections in patients with continuous flow left ventricular assist devices

摘要

Blood stream infections (BSIs) are common in patients with continuous flow left-ventricular assist devices (CF-LVADs). Whether CF-LVADs modulate the febrile response to BSIs is unknown. We retrospectively compared the febrile response to BSIs in heart failure (HF) patients with CF-LVADs versus a control population of HF patients receiving inotropic infusions. BSIs were adjudicated using the Center of Disease Control and Prevention and the National Healthcare Safety Network criteria. Febrile status (temperature ≥100.4°F, 38°C), temperature at presentation with BSI, and highest temperature within 72 hours (Tmax) were collected. We observed 59 BSIs in LVAD patients and 45 BSIs in controls. LVAD patients were more likely to be afebrile and to have a lower temperature at presentation than control (88% vs. 58%, p=0.002 and 98.6±1.3 vs. 99.8±1.8, p=0.0009, respectively). By 72 hours, the difference in afebrile status diminished (53% vs. 44%, p=0.42), and the Tmax was similar between the LVAD and control groups (100.3°F±1.6 vs. 100.8°F±1.5, respectively, p=0.10). In conclusion, at presentation with a BSI, the vast majority of CF-LVAD patients were afebrile, an event which occurred at a higher frequency when compared to patients with advanced HF on chronic inotropes via an indwelling venous catheter. These data alert clinicians to have a very low threshold to obtain blood cultures in CF-LVAD patients even in the absence of fever. Further study is needed to determine whether a delayed or diminished febrile response represents another pathophysiological consequence of CF-LVADs.