•Over 9% of patients hospitalized for COVID-19 will present a co-infection.•Independent risk factors for co-infection were identified.•When procalcitonin values are <0.2 ng/mL, co-infection is very ...rare.•High ferritin values and oxygen saturation >94% are also uncommon in co-infection.
We described the current incidence and risk factors of bacterial co-infection in hospitalized patients with COVID-19.
Observational cohort study was performed at the Hospital Clinic of Barcelona (February 2020–February 2021). All patients with COVID-19 who were admitted for >48 hours with microbiological sample collection and procalcitonin (PCT) determination within the first 48 hours were included.
A total of 1125 consecutive adults met inclusion criteria. Co-infections were microbiologically documented in 102 (9.1%) patients. Most frequent microorganisms were Streptococcus pneumoniae (79%), Staphylococcus aureus (6.8%), and Haemophilus influenzae (6.8%). Test positivity was 1% (8/803) for blood cultures, 10.1% (79/780) for pneumococcal urinary antigen test, and 11.4% (15/132) for sputum culture. Patients with PCT higher than 0.2, 0.5, 1, and 2 ng/mL had significantly more co-infections than those with lower levels (p=0.017, p=0.031, p<0.001, and p<0.001, respectively). In multivariate analysis, oxygen saturation ≤94% (OR 2.47, CI 1.57–3.86), ferritin levels <338 ng/mL (OR 2.63, CI 1.69–4.07), and PCT higher than 0.2 ng/mL (OR 1.74, CI 1.11–2.72) were independent risk factors for co-infection at hospital admission owing to COVID-19.
Bacterial co-infection in patients hospitalized for COVID-19 is relatively common. However, clinicians could spare antibiotics in patients with PCT values <0.2, especially with high ferritin values and oxygen saturation >94%.
Background
We described the real‐life epidemiology and causes of infections on the different therapy phases in patients undergoing chimeric antigen receptor (CAR) T‐cells directed towards CD19+ or ...BCMA+ cells.
Methods
All consecutive patients receiving CAR T‐cell therapy at our institution were prospectively followed‐up. We performed various comparative analyses of all patients and subgroups with and without infections.
Results
Ninety‐one adults mainly received CAR T‐cell therapy for acute leukaemia (53%) and lymphoma (33%). We documented a total of 77 infections in 47 (52%) patients, 37 (48%) during the initial neutropenic phase and 40 (52%) during the non‐neutropenic phase. Infections during the neutropenic phase were mainly due to bacterial (29, 78%): catheter infections (11 38% cases), endogenous source (5 17%), and Clostridioides difficile (5 17%). Patients receiving corticosteroids after CAR T‐cell therapy had a higher risk of endogenous infection (100% vs. 16%; p = .006). During the non‐neutropenic phase, bacterial infections remained very frequent (24, 60%), mainly with catheter source (8, 33%). Respiratory tract infections were common (17, 43%).
Conclusions
Infections after CAR T‐cell therapy were frequent. During the neutropenic phase, it is essential to prevent nosocomial infections and balance the use of antibiotics to lower endogenous bacteraemia and Clostridial infection rates.
We aimed to describe the clinical outcomes and duration of viral shedding in high-risk patients with haematological malignancies hospitalized with COVID-19 during Omicron variant predominance who ...received early treatment with antivirals.
We conducted a prospective observational study on high-risk haematological patients admitted in our hospital between December 2021 and March 2022. We performed detection techniques on viral subgenomic mRNAs until negative results were obtained to document active, prolonged viral replication.
This analysis included 60 consecutive adults with high-risk haematological malignancies and COVID-19. All of these patients underwent early treatment with remdesivir. Thirty-two (53%) patients received combined antiviral strategies, with sotrovimab or hyperimmune plasma being added to remdesivir. The median length of viral replication-as measured by real-time RT-PCR and/or subgenomic RNA detection-was 20 (IQR 14-28) days. Prolonged viral replication (6 weeks after diagnosis) was documented in six (10%) patients. Only two patients had prolonged infection for more than 2 months. Overall mortality was 5%, whereas COVID-19-related mortality was 0%.
Current outcomes of high-risk patients with haematological malignancies hospitalized with COVID-19 during Omicron variant predminance are good with the use of early antiviral strategies. Persistent viral shedding is uncommon.
•A novel dynamic borehole heat exchanger model is presented.•The B2G dynamic model is coupled to the g-function steady state model.•The complete GSHE model has been programmed in TRNSYS.•Model ...performance has been validated against experimental data.
Ground-source heat pump (GSHP) systems represent one of the most promising techniques for heating and cooling in buildings. These systems use the ground as a heat source/sink, allowing a better efficiency thanks to the low variations of the ground temperature along the seasons. The ground-source heat exchanger (GSHE) then becomes a key component for optimizing the overall performance of the system. Moreover, the short-term response related to the dynamic behaviour of the GSHE is a crucial aspect, especially from a regulation criteria perspective in on/off controlled GSHP systems. In this context, a novel numerical GSHE model has been developed at the Instituto de Ingeniería Energética, Universitat Politècnica de València. Based on the decoupling of the short-term and the long-term response of the GSHE, the novel model allows the use of faster and more precise models on both sides. In particular, the short-term model considered is the B2G model, developed and validated in previous research works conducted at the Instituto de Ingeniería Energética. For the long-term, the g-function model was selected, since it is a previously validated and widely used model, and presents some interesting features that are useful for its combination with the B2G model. The aim of the present paper is to describe the procedure of combining these two models in order to obtain a unique complete GSHE model for both short- and long-term simulation. The resulting model is then validated against experimental data from a real GSHP installation.
Abstract
Objectives
To describe current resistance to the β-lactams empirically recommended in the guidelines in bloodstream infection (BSI) episodes caused by Gram-negative bacilli (GNB).
Methods
...Retrospective, multicentre cohort study of the last 50 BSI episodes in haematological patients across 14 university hospitals in Spain. Rates of inappropriate empirical antibiotic therapy (IEAT) and impact on mortality were evaluated.
Results
Of the 700 BSI episodes, 308 (44%) were caused by GNB, mainly Escherichia coli (141; 20.1%), Klebsiella spp. (56; 8%) and Pseudomonas aeruginosa (48; 6.9%). Among GNB BSI episodes, 80 (26%) were caused by MDR isolates. In those caused by Enterobacterales, 25.8% were ESBL producers and 3.5% were carbapenemase producers. Among P. aeruginosa BSI episodes, 18.8% were caused by MDR isolates. Overall, 34.7% of the isolated GNB were resistant to at least one of the three β-lactams recommended in febrile neutropenia guidelines (cefepime, piperacillin/tazobactam and meropenem). Despite extensive compliance with guideline recommendations (91.6%), 16.6% of BSI episodes caused by GNB received IEAT, which was more frequent among MDR GNB isolates (46.3% versus 6.1%; P < 0.001). Thirty day mortality was 14.6%, reaching 21.6% in patients receiving IEAT.
Conclusions
Current resistance to empirical β-lactams recommended in febrile neutropenia guidelines is exceedingly high and IEAT rates are greater than desired. There is an urgent need to adapt guidelines to current epidemiology and better identify patients with a high risk of developing MDR GNB infection.
ABSTRACT
Background
We aimed to describe a cohort of hematologic patients with COVID‐19 treated with antivirals early.
Methods
Non‐interventional chart review study. Comparison of baseline ...characteristics and outcomes in high‐risk hematologic patients treated with remdesivir between December 2021 and April 2022 versus those treated with nirmatrelvir/ritonavir between May and August 2022.
Results
Eighty‐three patients were analyzed. Forty‐two received remdesivir, and 41 nirmatrelvir/ritonavir. Patients with remdesivir were younger, vaccinated with lower number of doses, and received prior corticosteroids less frequently and sotrovimab, hyperimmune plasma and corticosteroids more often. Viral shedding median (IQR) duration was 18 (13–23) and 11 (8–21) days in the remdesivir and nirmatrelvir/ritonavir groups, respectively (p = 0.004). Median (IQR) Ct values before treatment were similar in both groups. Within 5 days of treatment, median (IQR) Ct values were 26 (23–29) and 33 (30–37) in the remdesivir and nirmatrelvir/ritonavir groups, respectively (p < 0.0001). All patients were hospitalized for remdesivir administration and only four (9.8%) in the nirmatrelvir/ritonavir group. The overall outcomes in this cohort of COVID‐19 patients with Omicron variant was good, as no patient needed oxygen or ICU admission. One patient in remdesivir group died from septic shock. No severe adverse event was recorded in both treatment groups.
Conclusions
Patients with hematologic malignancies and non‐severe COVID‐19 who received nirmatrelvir/ritonavir experienced faster decrease in viral load and shorter viral shedding. Furthermore, besides the advantage of oral administration, nirmatrelvir/ritonavir administration reduced the need of hospital admission.
•FEM model applies a uniform temperature boundary condition at the borehole wall.•Highly conductive material concept to set a temperature condition at boreholes wall.•Test against measured real data ...to predict daily temperatures for variable loads.•Tool to improve accuracy in generation of g-functions for specific situations.
The design of a borehole field should be based on a long-term simulation of its thermal response for the intended energy loads. A well-known method to evaluate the response is based on a pre-calculated dimensionless function, the g-function. When calculating g-functions, there are two commonly used approaches for treating the boundary condition at the borehole wall: a constant heat flux at every instant of time, or a uniform temperature at a constant total heat flow to the borehole field. This paper is focused on a new approach to model the thermal process of borehole fields; in particular with a precise representation of a uniform temperature boundary condition at the borehole wall. The main purpose of this model is to be used as a research tool to either generate g-functions for particular cases or handle situations that cannot be addressed by others methods. First, the almost constant temperature along the borehole heat exchanger in operation requires a boundary condition of essentially isothermal boreholes along the depth. In a common case, the borehole heat exchangers are connected in parallel, thus all boreholes should have the same temperature. Also, the total heat flow to the borehole field should be constant over time. For this purpose, a numerical model in which the boreholes are filled with a hypothetical highly conductive material has been built, reproducing the isothermal condition. By thermally interconnecting the boreholes, the equal temperature condition is satisfied. Finally, the specified total heat flow is fed into one spot at the highly conductive material. The model is validated by generating g-functions of some simple borehole field configurations. The g-functions present, in general, a good agreement with the existing solutions for a similar boundary condition. Moreover, the model is also tested against real experimental data from a 2×3 borehole field at an office building. The simulated daily fluid temperatures are compared with measured daily fluid temperatures for the sixth year of operation. The simulated values present, in general, a good agreement with the measured data. The results show that there are no significant differences with regard to the boundary conditions at the borehole wall, which for this specific case is due to the fact that the system is thermally balanced.
The required length of vertical ground heat exchangers (GHX) used in ground-coupled heat pump (GCHP) systems is determined so that the outlet temperature from the GHX remains within certain limits ...for the worst ground load conditions. These conditions may not necessarily occur after 10 or 20 years of operation, as is usually assumed, but often occur during the first year of operation. The primary objective of this paper is to develop a general methodology for the calculation of the total required bore field length on a monthly basis during the first year of operation using the framework of the ASHRAE bore field sizing method. It is a three phase process. The first phase consists of analyzing and ordering ground loads according to the first month of operation. Next, a first set of required lengths is determined by using the analyzed ground load components and assuming a temperature penalty T.sub.p = 0. Then, an iterative process to calculate the temperature penalty at the end of each month is carried out to obtain the final required length for the worst conditions. The methodology is exemplified in a particular case with a slight annual cooling thermal imbalance and with a high influence of the hourly peak in heating. For this particular case, it is shown that the required bore field length occurs during the first year and that the starting month of operation has a strong influence on the results. Finally, it is shown that it is possible to reduce the borehole spacing when the annual ground load is quasibalanced. In the case studied here, the minimum length occurs for a borehole-to-borehole spacing of about 3.2 m (10.50 ft).
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