Retrospective Observational Study of Complete Blood Count (CBC) Parameters and ICU Mortality of COVID-19 Disease in Delta Variant and Omicron Variant in a Community-Based Hospital in New York City.

BACKGROUND: Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) is the official name of COVID-19, a respiratory infection that had the first case reported from the Hubei province of China on December 8, 2019. This virus is the main etiological agent behind the most dreaded pandemic of pneumonia that has spread to the entire world in a brief period and continues to pose a threat. The first wave corresponded with the period from February 2020 to June 2020, the Delta variant occurred around the middle of June 2021 and the Omicron wave was reported from December 2021 to February 2022. Objective: This study aims to compare the Delta and the Omicron variants of COVID-19 infection in a community-based hospital in New York City considering the comparison of ICU admissions in both variants. We aim to study the comparison of complete blood count (CBC) parameters and inflammatory markers of patients admitted to ICU stratified by two waves of COVID-19 infection. We aim to analyze the association of CBC parameters at admission and the discharge during ICU stay in both variants. We also aim to study the association of CBC parameters at admission and discharge with ICU mortality in both variants. METHODS: We conducted a retrospective observational study based on data from randomly selected hospitalized patients with COVID-19 in a community-based hospital in New York City during the Delta variant and the Omicron wave. A total of 211 patients COVID-19 positive from June to July 2021 (Delta variant) and 148 patients from December to February 2022 (Omicron wave) were included in the study. A comparison was done between the basic characteristics of patients with and without ICU admissions in both variants of COVID-19. We compared the relationship of different parameters of CBC (hemoglobin (Hgb), white blood count (WBC), lymphocytes, neutrophils, and platelets) on ICU admission and further analyzed any changes associated with ICU mortality. Logistic regression was performed to evaluate the relationship of different presenting CBCs on patients' disposition to ICU.  Result: A total of 211 patients (106 female) in the Delta wave (2021 variant) and 148 patients (80 female) in the Omicron wave (2022 variant) with an average ages of 60.9 ±18.10 (Delta variant) and 63.2 ± 19.10 (Omicron variant) were included in this study. There were 45 patients (21.3%) in the Delta wave and 42 patients (28.4%) in the Omicron wave were admitted to ICU. The average length of hospital stay was seven days in the Delta wave and nine days in the Omicron wave. No significant association was found between presenting cell count and ICU admission (p>0.05). Significant associations were found between different cell counts on admission and discharge and death in Delta waves except Hgb and platelets on admission. However, in the Omicron variant, a significant association was found only between WBC on admission and discharge, and Hgb and neutrophil on discharge with death in the univariate model. CONCLUSION:  Comparative study of different clinical parameters between the Delta and the Omicron variants of COVID-19 with the correlation of ICU stay and mortality can be used as a beneficial modality in assessing the outcome of the disease.

Utility of D-dimer as a Prognostic Factor in SARS CoV2 Infection: A Review.

Coronavirus Disease-2019 (COVID-19) is currently a public health emergency and has been listed by the World Health Organization (WHO) as a pandemic. It has commonly been associated with pulmonary manifestations and there is a growing body of evidence of multisystem involvement of the virus. As evidenced by various case reports and cohort studies, COVID-19-associated coagulopathy has been a common manifestation amongst the critically ill and has been associated with increased mortality. The presence of venous thromboembolic events in patients who are critically ill due to COVID-19 has prompted the adoption of anticoagulation regimens aimed at preventing thromboembolic phenomena. Coagulation abnormalities have also been implicated in the progression and the severity of COVID-19 related acute respiratory distress syndrome (ARDS) and disseminated intravascular coagulation (DIC). There is strong evidence that D-dimer levels help predict which patients are at risk of thromboembolic events, progression to ARDS, DIC, immune dysregulation and mortality. We will review the utility of D-dimer as screening tool and in the risk stratification of COVID-19 patients prone to developing thromboembolic events, DIC, immune dysregulation and death. To date, the studies that have been published show the presence of elevated D-dimer levels in both the adult and pediatric populations and the measured level correlates with disease severity. Studies have also shown the relative increase of D-dimer levels in non-survivors compared to survivors. The elevation of D-dimer levels has shown to guide clinical decision making, namely the initiation of therapeutic anticoagulation and mortality benefit in patients with severe COVID-19 pneumonia compared to severe non COVID-19 pneumonia. Although the current body of literature suggested the use of D-dimer as a risk stratification tool and as a test to augment clinical judgement regarding the initiation of anticoagulation, randomized control trials are needed to fully understand the relationship between COVID-19 infection and the efficacy of D-dimer assays in clinical decision making.

Living donor liver transplant outcomes during the COVID-19 pandemic: does a decrease in case volume impact the overall outcomes?

Background: High-volume centers (HVCs) are classically associated with better outcomes. During the coronavirus disease 2019 (COVID-19) pandemic, there has been a decrease in the regular liver transplantation (LT) activity at our center. This study analyzed the effect of the decline in LT on posttransplant patient outcomes at our HVC. Methods: We compared the surgical outcomes of patients who underwent LT during the COVID-19 pandemic lockdown (April 1, 2020 to September 30, 2020) with outcomes in the pre-pandemic calendar year (April 1, 2019 to March 31, 2020). Results: During the 6 months of pandemic lockdown, 60 patients underwent LT (43 adults and 17 children) while 228 patients underwent LT (178 adults and 50 children) during the pre-pandemic calendar year. Patients in the pandemic group had significantly higher model for end-stage liver disease (MELD) scores (24.39±9.55 vs. 21.14±9.17, P=0.034), Child-Turcotte-Pugh scores (11.46±2.32 vs. 10.25±2.24, P=0.03), and incidence of acute-on-chronic liver failure (30.2% vs. 10.2%, P=0.002). Despite performing LT in sicker patients with COVID-19-related challenges, the 30-day (14% vs. 18.5%, P=0.479), 3-month (16.3% vs. 20.2%, P=0.557), and 6-month mortality rates (23.3% vs. 28.7%, P=0.477) were lower, but not statistically significant when compared to the pre-pandemic cohort. Conclusions: During the COVID-19 pandemic lockdown the number of LT procedures performed at our HVC declined by half because prevailing conditions allowed LT in very sick patients only. Despite these changes, outcomes were not inferior during the pandemic period compared to the pre-pandemic calendar year. Greater individualization of patient care contributed to non-inferior outcomes in these sick recipients.

Observational Study of Thrombotic Events in a Random Cohort of Hospitalized COVID-19 Patients at a Community-Based Hospital of New York City During the Beginning of the 2020 Pandemic.

Coronavirus disease 2019 (COVID-19) continues to pose an unprecedented challenge for the entire world and the healthcare system. Different theories have been proposed elucidating the pathophysiological mechanisms attributing to high mortality and morbidity in COVID-19 infection. Out of them, thrombosis and procoagulant state have managed to earn the maximum limelight. We conducted an observational study based on data from randomly selected 349 hospitalized patients with COVID-19 infection in a community-based hospital in New York City during the first wave of the COVID-19 viral surge in March 2020. The main objective of our study was to assess the risk and occurrence of thrombotic events (both venous and arterial) among the hospitalized patients including the intensive care unit (ICU) and non-ICU admissions with confirmed COVID-19 infection. The primary outcome in our study was defined as the thrombotic events that included myocardial infarction (MI), deep venous thrombosis (DVT), cerebrovascular accidents (CVA), and pulmonary embolism (PE). The study correlated the association of thrombotic events with the level of biomarkers of interest: D-dimer >1000 ng/ml, troponin-I >1 ng/ml, or both. The association of D-dimers and troponin-I with thrombotic events was measured using both univariate and multivariate Cox proportional hazard (PH) regression analysis. Out of a total of 349 patients, 78 patients (22.35%) were found to have elevated biomarkers (D-dimer >1000 ng/ml and/or troponin-I >1 ng/ml) and were categorized as a high-risk group. Eighty-nine patients developed thrombotic complications (evidence of more than one thrombotic event was found in several patients). Two-hundred seventy-one (77.65%) patients had no documentation of thrombosis. The incidence of thrombotic events included myocardial infarction (MI; N=45; 12.8%), cerebrovascular accidents (CVA; N=16; 4.5%), deep venous thrombosis (DVT; N=16; 4.5%), and pulmonary embolism (PE; N=9; 2.57%).

Elliptical Pipette Generated Large Microdroplets for POC Visual ddPCR Quantification of Low Viral Load.

Rapid point-of-care (POC) quantification of low virus RNA load would significantly reduce the turn-around time for the PCR test and help contain a fast-spreading epidemic. Herein, we report a droplet digital PCR (ddPCR) platform that can achieve this sensitivity and rapidity without bulky lab-bound equipment. The key technology is a flattened pipette tip with an elliptical cross-section, which extends a high aspect-ratio microfluidic chip design to pipette scale, for rapid (<5 min) generation of several thousand monodispersed droplets ∼150 to 350 µm in size with a CV of ∼2.3%. A block copolymer surfactant (polyoxyalkylene F127) is used to stabilize these large droplets in oil during thermal cycling. At this droplet size and number, positive droplets can be counted by eye or imaged by a smartphone with appropriate illumination/filtering to accurately quantify up to 100 target copies. We demonstrate with 2019 nCoV-PCR assay LODs of 3.8 copies per 20 µL of sample and a dynamic range of 4-100 copies. The ddPCR platform is shown to be inhibitor resistant with spiked saliva samples, suggesting RNA extraction may not be necessary. It represents a rapid 1.5-h POC quantitative PCR test that requires just a pipette equipped with elliptical pipette tip, a commercial portable thermal cycler, a smartphone, and a portable trans-illuminator, without bulky and expensive micropumps and optical detectors that prevent POC application.