Wieruszewski, P M

Objectives: Consensus clinical criteria for refractory septic shock were recently developed, but the incidence and outcomes with these criteria are unknown. There were two aims: 1) to describe the incidence of refractory septic shock and 2) to assess outcomes of patients with septic shock meeting refractory septic shock criteria compared with those who did not. Design: Multicohort, retrospective study. For aim 1, a descriptive epidemiologic study was designed to ascertain the cumulative incidence of refractory septic shock in patients with septic shock. For aim 2, a cohort study was conducted to compare hospital mortality between patients meeting refractory septic shock clinical criteria compared with those who did not. Setting: Large U.S. health system from 2012 to 2024. Patients: Adults (age ≥ 18 yr) meeting both Centers for Disease Control and Prevention Adult Sepsis Event and Sepsis-3 clinical criteria for septic shock. Patients with missing hospital discharge disposition and incomplete vasopressor dosage information were excluded. Interventions: None. Measurements and Main Results: Clinical criteria for refractory septic shock were operationalized as concomitant occurrence of norepinephrine (base) equivalent greater than 0.5 µg/kg/min and lactate greater than 2 mmol/L. Risk-adjusted hospital mortality was assessed with a generalized linear mixed-effects model with a random effect for hospital and fixed effects for age, sex, Elixhauser Comorbidity Index, and Sequential Organ Failure Assessment (original description, without cardiovascular component). Of 35,914 patients assessed, 15,732 patients with septic shock were included. Refractory septic shock occurred in 3423 patients (21.8%), with a cumulative incidence of 218 cases (95% CI, 211–224) per 1000 patients with septic shock. Hospital mortality with refractory septic shock was 64.4%, and risk-adjusted hospital mortality odds were 4.87-fold higher (95% CI, 4.46–5.31) compared with patients without refractory septic shock. Conclusions: Clinical criteria for refractory septic shock were fulfilled in about one in five patients with septic shock and associated with substantially higher mortality.

Abstract Rationale Extracorporeal membrane oxygenation (ECMO) is an increasingly utilized form of life support for patients with cardiac and/or respiratory failure. Fungal infections remain a serious challenge in patients supported by ECMO, with an estimated prevalence of up to 10% and high morbidity and mortality. While routine antifungal prophylaxis is uncommon in ECMO centers and widely debated, its impact on incidence, pathogenic organisms, resistance patterns, and outcomes has not been described. Methods This was a ten-year experience study of fungemia in patients receiving ECMO where most patients received antifungal prophylaxis. Institutional protocol was to prescribe prophylactic fluconazole based on risk stratification, substituted with echinocandins if indicated. Adults (18 years and older) with ECMO runs between 2014-2024 were screened for fungal organism growth on culture, then narrowed to those with positive blood cultures drawn in the window from 24 hours after cannulation through 72 hours after decannulation. Clinical, microbiological, and outcomes data were descriptively summarized. Institutional review board approved with a waiver of informed consent. Results Among 1,039 adult ECMO runs (979 patients), thirteen patients with fungemia were identified for a calculated incidence rate of 1.29 per 1000 ECMO days (95% CI 0.75 to 2.23). Twelve patients (92%) received antifungal prophylaxis; 85% had echinocandin and 38% azole exposure, with some overlap. Median duration of antifungal exposure was 14 days prior to positive culture. Seven patients (54%) had an open sternum at the time of ECMO cannulation, while 11 (85%) had femoral ECMO access. Four patients (31%) had Candida species isolated from other sources prior to fungemia (mediastinum and respiratory system). Candida parapsilosis (31%), C. albicans (23%), and C. guilliermondii (15%) were the most common isolates. The most likely sources were vascular access catheters (38%) and mediastinum (31%). Seven patients (54%) had suspected or confirmed seeding of ECMO hardware after positive blood cultures, though only two circuit exchanges were performed. Four patients (31%) showed evidence of non-susceptibility to their prophylactic antifungal class (Table 1), with a median 35-day exposure prior to positivity among those patients. Only 62% of patients demonstrated blood culture clearance (median 3 [IQR 2.5-7.75] days). Nearly all patients (92%) died within the hospital stay, including all patients with resistant organisms. Conclusions In an ECMO center with routine antifungal prophylaxis practices, the rate of fungemia identified during ECMO support was low. When fungemia developed, there was a high proportion of drug resistance and mortality. This abstract is funded by: None