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Background: Nearly 30,000 patients with coronavirus disease-2019 have been hospitalized in New York City as of April 14 th , 2020. Data on the epidemiology, clinical course, and outcomes of critically ill patients with COVID-19 in this setting are needed. Methods:We prospectively collected clinical, biomarker, and treatment data on critically ill adults with laboratory-confirmed-COVID-19 admitted to two hospitals in northern Manhattan between March 2 nd and April 1 st , 2020. The primary outcome was in-hospital mortality.Secondary outcomes included frequency and duration of invasive mechanical ventilation, frequency of vasopressor use and renal-replacement-therapy, and time to clinical deterioration following hospital admission. The relationship between clinical risk factors, biomarkers, and inhospital mortality was modeled using Cox-proportional-hazards regression. Each patient had at least 14 days of observation. Results:Of 1,150 adults hospitalized with COVID-19 during the study period, 257 (22%) were critically ill. The median age was 62 years (interquartile range [IQR] 51-72); 170 (66%) were male. Two-hundred twelve (82%) had at least one chronic illness, the most common of which were hypertension (63%; 162/257) and diabetes mellitus (36%; 92/257). One-hundred-thirtyeight patients (54%) were obese, and 13 (5%) were healthcare workers. As of April 14 th , 2020, in-hospital mortality was 33% (86/257); 47% (122/257) of patients remained hospitalized. Twohundred-one (79%) patients received invasive mechanical ventilation (median 13 days [IQR 9-17]), and 54% (138/257) and 29% (75/257) required vasopressors and renal-replacementtherapy, respectively. The median time to clinical deterioration following hospital admission was 3 days (IQR 1-6). Older age, hypertension, chronic lung disease, and higher concentrations of interleukin-6 and d-dimer at admission were independently associated with in-hospital mortality. All rights reserved. No reuse allowed without permission.(which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.

27A surge of patients with coronavirus disease 2019 presenting to New York City hospitals in 28March 2020 led to a sharp increase blood culture utilization, which overwhelmed the capacity of 29 automated blood culture instruments. We sought to evaluate the utilization and diagnostic yield of blood 30 cultures during the COVID-19 pandemic to determine prevalence and common etiologies of bacteremia, 31 and to inform a diagnostic approach to relieve blood culture overutilization. We performed a retrospective 32 cohort analysis of 88,201 blood cultures from 28,011 patients at a multicenter network of hospitals within 33 New York City to evaluate order volume, positivity rate, time to positivity, and etiologies of positive 34 cultures in COVID-19. Ordering volume increased by 34.8% in the second half of March 2020 compared 35 to the first half of the month. The rate of bacteremia was significantly lower among COVID-19 patients 36 (3.8%) than COVID-19 negative patients (8.0%) and those not tested (7.1%), p < 0.001. COVID-19 37 patients had a high proportion of organisms reflective of commensal skin microbiota, reducing the 38 bacteremia rate to 1.6% when excluded. More than 98% of all positive cultures were detected within 4 39 days of incubation. Bloodstream infections are very rare for COVID-19 patients, which supports the 40 judicious use of blood cultures in the absence of compelling evidence for bacterial co-infection. Clear 41 communication with ordering providers is necessary to prevent overutilization of blood cultures during 42 patient surges, and laboratories should consider shortening the incubation period from 5 days to 4 days, if 43 necessary, to free additional capacity. 44 45 46 47 48

Objectives: The 'hypervirulent' variant of Klebsiella pneumoniae (hvKp) is a predominant cause of community-acquired pyogenic liver abscess in Asia, and is an emerging pathogen in Western countries. hvKp infections have demonstrated 'metastatic' dissemination in immunocompetent hosts, an unusual mode of infection associated with severe complications. Two cases alerted us to the possible presence of hvKp at our hospital, both involving elderly Hispanic males who presented with recurrent fever, bacteraemia, epigastric pain and liver abscesses/phlegmon, thus prompting an assessment of hvKp prevalence. Methods: A surveillance of K. pneumoniae blood, body fluid and wound isolates was conducted using real-time PCR to detect virulence-associated genes (uni-rmpA, iucA and peg344). Positive isolates were further characterized by wzi gene sequencing to determine capsular types (K-type) and by multilocus sequence typing and pulsed-field gel electrophoresis to determine strain relatedness. Results: Four-hundred and sixty-three K. pneumoniae isolates, derived from 412 blood, 21 body fluids and 30 abdominal wound specimens, were screened over a 3-year period. Isolates included 98 multidrugresistant strains. Eighteen isolates from 17 patients, including two from the index patient, screened positive for all three virulence genes. Sixteen of 18 positive isolates had K-types associated with hvKp, and isolates from different patients were unrelated strains, indicating likely community acquisition. Of 13 patients with significant morbidity, five died; eight patients had co-existing hepatobiliary disease, and six had diabetes mellitus. Conclusions: Multiple strains of hvKp are emerging in New York City and are associated with high mortality relative to multidrug-resistant and classical Klebsiella infections. Co-existing hepatobiliary disease appears to be a potential risk factor for these infections.

The safety and efficacy of tocilizumab for the treatment of severe respiratory symptoms due to COVID‐19 remain uncertain, in particular among solid organ transplant (SOT) recipients. Thus, we evaluated the clinical characteristics and outcomes of 29 hospitalized SOT recipients who received tocilizumab for severe COVID‐19, compared to a matched control group who did not. Among a total of 117 total SOT recipients hospitalized with COVID‐19, 29 (24.8%) received tocilizumab. The 90‐day mortality was significantly higher among patients who received tocilizumab (41%) compared to those who did not (20%, P = .03). When compared to control patients matched by age, hypertension, chronic kidney disease, and administration of high dose corticosteroids, there was no significant difference in mortality (41% vs 28%, P = .27), hospital discharge (52% vs 72%, P = .26), or secondary infections (34% vs 24%, P = .55). Among patients who received tocilizumab, there was also no difference in mortality based on the level of oxygen support (intubated vs not intubated) at the time of tocilizumab initiation. In this matched cohort study, tocilizumab appeared to be safe but was not associated with decreased 90‐day mortality. Larger randomized studies are needed to identify whether there are subsets of SOT recipients who may benefit from tocilizumab for treatment of COVID‐19.

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Driveline infection (DLI) is common after left ventricular assist device (LVAD). Limited data exist on DLI prevention and management. We investigated the impact of standardized driveline care initiatives, specific pathogens, and chronic antibiotic suppression (CAS) on DLI outcomes. 591 LVAD patients were retrospectively categorized based on driveline care initiatives implemented at our institution (2009-2019). Era (E)1: nonstandardized care; E2: standardized driveline care protocol; E3: addition of marking driveline exit site; E4: addition of "no shower" policy. 87(15%) patients developed DLI at a median (IQR) of 403(520) days. S. aureus and P. aeruginosa were the most common pathogens. 31 (36%) of DLI patients required incision and drainage (I&D) and 5 (5.7%) device exchange. P. aeruginosa significantly increased risk for initial I&D (HR 2.7, 95% CI, 1.1-6.3) and recurrent I&D or death (HR 4.2, 95% CI, 1.4-12.5). Initial I&D was associated with a significant increased risk of death (HR 2.92 (1.33-6.44); P = 0.008) when compared to patients who did not develop DLI. Implementation of standardized driveline care protocol (E2) was associated with increased 2-year freedom from DLI compared to nonstandardized care (HR 0.36, 95% CI, 0.2-0.6, P < 0.01). Additional preventive strategies (E3&E4) showed no further reduction in DLI rates. 57(65%) DLI patients received CAS, 44% of them required escalation to intravenous antibiotics and/or I&D. Presence of P. aeruginosa DLI markedly increased risk for I&D or death. Conditional survival of patients progressing to I&D is diminished. Standardized driveline care protocol was associated with a significant reduction in DLI, while additional preventive strategies require further testing.