A RETROSPECTIVE STUDY OF CT IMAGING OF PULMONARY EMBOLISM IN PATIENTS WITH COVID-19 PNEUMONIA USING DUAL ENERGY CT

Background Pulmonary Embolism(PE) is a known complication of COVID-19, and CT pulmonary angiography (CTPA) is commonly recommended for its detection. DECT offers additional value in diagnosing COVID-19 and its complications, particularly in detecting small pulmonary emboli. The aimed of this study is to assess the presence of PE , to determine the location of the thrombus and assess the utility of iodine density mapping in evaluating embolism with DECT. Methodology Retrospective study from May until September 2021 conducted on 163 patients with COVID-19 infection (positive PCR) and suspected PE. Results 163 patients PE suspicions with confirmed COVID-19 underwent CTPA. 19 patients were diagnosed with PE with a predominant segmental distribution. All the PE positive patients showed increased in D-Dimer value. Interestingly, four cases initially interpreted as PE negative by the previous radiologist were later found to be PE positive. The study found no significant difference in detecting pulmonary embolism between the conventional algorithm and dual-source energy reconstruction. However, DECT demonstrated practical advantages over conventional CTPA in detecting acute PE. Conclusion Currently, DECT is not considered a routine diagnostic procedure for evaluating PE according to guidelines. However, with increasing familiarity among radiologists and adjustments in image acquisition and postprocessing methods, the application of DECT for PE evaluation could expand. This could lead to the recognition of its benefits and the potential to enhance the detection and confident diagnosis of pulmonary embolism

An Imaging Overview of COVID-19 ARDS in ICU Patients and Its Complications: A Pictorial Review

A significant proportion of patients with COVID-19 pneumonia could develop acute respiratory distress syndrome (ARDS), thus requiring mechanical ventilation, and resulting in a high rate of intensive care unit (ICU) admission. Several complications can arise during an ICU stay, from both COVID-19 infection and the respiratory supporting system, including barotraumas (pneumothorax and pneumomediastinum), superimposed pneumonia, coagulation disorders (pulmonary embolism, venous thromboembolism, hemorrhages and acute ischemic stroke), abdominal involvement (acute mesenteric ischemia, pancreatitis and acute kidney injury) and sarcopenia. Imaging plays a pivotal role in the detection and monitoring of ICU complications and is expanding even to prognosis prediction. The present pictorial review describes the clinicopathological and radiological findings of COVID-19 ARDS in ICU patients and discusses the imaging features of complications related to invasive ventilation support, as well as those of COVID-19 itself in this particularly fragile population. Radiologists need to be familiar with COVID-19's possible extra-pulmonary complications and, through reliable and constant monitoring, guide therapeutic decisions. Moreover, as more research is pursued and the pathophysiology of COVID-19 is increasingly understood, the role of imaging must evolve accordingly, expanding from the diagnosis and subsequent management of patients to prognosis prediction

Venous thromboembolism in covid-19 compared to non-covid-19 cohorts: A systematic review with meta-analysis

Background: A high incidence of venous thromboembolism (VTE) is reported in hospitalized COVID-19 patients, in particular in patients admitted to the intensive care unit (ICU). In patients with respiratory tract infections, including influenza A (H1N1), many studies have demonstrated an increased incidence of thromboses, but evidence is lacking regarding the risk difference (RD) of the occurrence of VTE between COVID-19 and non-COVID-19 patients. Methods: In this systematic review with meta-analysis, we evaluated the RD of the occurrence of VTE, pulmonary embolism (PE), and deep venous thrombosis (DVT) between COVID-19 and other pulmonary infection cohorts, in particular H1N1, and in an ICU setting. We searched for all studies comparing COVID-19 vs. non-COVID-19 regarding VTE, PE, and DVT. Results: The systematic review included 12 studies and 1,013,495 patients. The RD for VTE in COVID-19 compared to non-COVID-19 patients was 0.06 (95% CI 0.11–0.25, p = 0.011, I2 = 97%), and 0.16 in ICU (95% CI 0.045–0.27, p = 0.006, I2 = 80%). The RD for PE between COVID-19 and non-COVID-19 patients was 0.03 (95% CI, 0.006–0.045, p = 0.01, I2 = 89%). The RD for PE between COVID-19 and non-COVID-19 patients was 0.021 in retrospective studies (95% CI 0.00–0.04, p = 0.048, I2 = 92%) and 0.11 in ICU studies (95% CI 0.06–0.16, p < 0.001, I2 = 0%). Conclusions: The growing awareness and understanding of a massive inflammatory response combined with a hypercoagulable state that predisposes patients to thrombosis in COVID-19, in particular in the ICU, may contribute to a more appropriate strategy of prevention and earlier detection of the thrombotic events

Pulmonary embolism in patients with COVID-19 and value of D-dimer assessment:a meta-analysis

Purpose To investigate, in a meta-analysis, the frequency of pulmonary embolism (PE) in patients with COVID-19 and whether D-dimer assessment may be useful to select patients for computed tomography pulmonary angiography (CTPA). Methods A systematic literature search was performed for original studies which reported the frequency of PE on CTPA in patients with COVID-19. The frequency of PE, the location of PE, and the standardized mean difference (SMD) of D-dimer levels between patients with and without PE were pooled by random effects models. Results Seventy-one studies were included. Pooled frequencies of PE in patients with COVID-19 at the emergency department (ED), general wards, and intensive care unit (ICU) were 17.9% (95% CI: 12.0-23.8%), 23.9% (95% CI: 15.2-32.7%), and 48.6% (95% CI: 41.0-56.1%), respectively. PE was more commonly located in peripheral than in main pulmonary arteries (pooled frequency of 65.3% [95% CI: 60.0-70.1%] vs. 32.9% [95% CI: 26.7-39.0%]; OR = 3.540 [95% CI: 2.308-5.431%]). Patients with PE had significantly higher D-dimer levels (pooled SMD of 1.096 [95% CI, 0.844-1.349]). D-dimer cutoff levels which have been used to identify patients with PE varied between 1000 and 4800 mu g/L. Conclusion The frequency of PE in patients with COVID-19 is highest in the ICU, followed by general wards and the ED. PE in COVID-19 is more commonly located in peripheral than in central pulmonary arteries, which suggests local thrombosis to play a major role. D-dimer assessment may help to select patients with COVID-19 for CTPA, using D-dimer cutoff levels of at least 1000 mu g/L

Pulmonary embolism severity before and during the COVID-19 pandemic

OBJECTIVES: Early in the coronavirus 2019 (COVID-19) pandemic, a high frequency of pulmonary embolism was identified. This audit aims to assess the frequency and severity of pulmonary embolism in 2020 compared to 2019. METHODS: In this retrospective audit, we compared computed tomography pulmonary angiography (CTPA) frequency and pulmonary embolism severity in April and May 2020, compared to 2019. Pulmonary embolism severity was assessed with the Modified Miller score and the presence of right heart strain was assessed. Demographic information and 30-day mortality was identified from electronic health records. RESULTS: In April 2020, there was a 17% reduction in the number of CTPA performed and an increase in the proportion identifying pulmonary embolism (26%, n = 68/265 vs 15%, n = 47/320, p < 0.001), compared to April 2019. Patients with pulmonary embolism in 2020 had more comorbidities (p = 0.026), but similar age and sex compared to 2019. There was no difference in pulmonary embolism severity in 2020 compared to 2019, but there was an increased frequency of right heart strain in May 2020 (29 vs 12%, p = 0.029). Amongst 18 patients with COVID-19 and pulmonary embolism, there was a larger proportion of males and an increased 30 day mortality (28% vs 6%, p = 0.008). CONCLUSION: During the COVID-19 pandemic, there was a reduction in the number of CTPA scans performed and an increase in the frequency of CTPA scans positive for pulmonary embolism. Patients with both COVID-19 and pulmonary embolism had an increased risk of 30-day mortality compared to those without COVID-19. ADVANCES IN KNOWLEDGE: During the COVID-19 pandemic, the number of CTPA performed decreased and the proportion of positive CTPA increased. Patients with both pulmonary embolism and COVID-19 had worse outcomes compared to those with pulmonary embolism alone

Presence of procoagulant peripheral blood mononuclear cells in severe COVID-19 patients relate to ventilation perfusion mismatch and precede pulmonary embolism

PURPOSE: Pulmonary emboli (PE) contribute substantially to coronavirus disease 2019 (COVID-19) related mortality and morbidity. Immune cell-mediated hyperinflammation drives the procoagulant state in COVID-19 patients, resulting in immunothrombosis. To study the role of peripheral blood mononuclear cells (PBMC) in the procoagulant state of COVID-19 patients, we performed a functional bioassay and related outcomes to the occurrence of PE. Secondary aims were to relate this functional assay to plasma D-dimer levels, ventilation perfusion mismatch and TF expression on monocyte subsets. METHODS: PBMC from an ICU biobank were obtained from 20 patients with a computed tomography angiograph (CTA) proven PE and compared to 15 COVID-19 controls without a proven PE. Functional procoagulant properties of PBMC were measured using a modified fibrin generation time (MC-FGT) assay. Tissue factor (TF) expression on monocyte subsets were measured by flow cytometry. Additional clinical data were obtained from patient records including end-tidal to arterial carbon dioxide gradient. RESULTS: MC-FGT levels were highest in the samples taken closest to the PE detection, similar to the end-tidal to arterial carbon dioxide gradient (ETCO2 - PaCO2), a measurement to quantify ventilation-perfusion mismatch. In patients without proven PE, peak MC-FGT relates to an increase in end-tidal to arterial carbon dioxide gradient. We identified non-classical, CD16 positive monocytes as the subset with increased TF expression. CONCLUSION: We show that the procoagulant state of PBMC could aid in early detection of PE in COVID-19 ICU patients. Combined with end-tidal to ETCO2 - PaCO2 gradient, these tests could improve early detection of PE on the ICU.</p

Using Quantitative D-Dimer to Determine the Need for Pulmonary CT Angiography in COVID-19 Patients

INTRODUCTION: COVID-19 has been frequently cited as a condition causing a pro-inflammatory state leading to hypercoagulopathy and increased risk for venous thromboembolism. This condition has thus prompted prior studies and screening models that utilize D-dimer for pulmonary embolism (PE) into question. The limited research to date has failed to provide tools or guidance regarding what COVID-19 positive patients should receive pulmonary CT angiography screening. This knowledge gap has led to missed diagnoses, CT overutilization, and increased morbidity and mortality. OBJECTIVE: The purpose of this study was to examine the utility of the quantitative D-dimer lab marker in a convenience sample of 426 COVID-19 positive patients to assist providers in determining the utility of pulmonary CT angiography. METHODS: The authors conducted a retrospective analysis on all COVID-19 positive patients within the Henry Ford Medical System between March 1st, 2020 through April 30th, 2020 who received pulmonary CT angiography and had a quantitative D-dimer lab drawn within 24 hours of CT imaging. RESULTS: Our sampling criteria yielded a total of n = 426 patients, of whom 347 (81.5%) were negative for PE and 79 (18.5%) were positive for PE. The average D-dimer in the negative PE group was 2.95 μg./mL. (SD 4.26), significantly different than the 9.15 μg./mL. (SD 6.80) positive PE group (P \u3c 0.05; 95% CI -7.8, -4.6). Theoretically, applying the traditional ≤ 0.5 μg./mL. D-dimer cut-off to our data would yield a sensitivity of 100% and specificity of 7.49% for exclusion of PE. Based on these results, the authors would be able to increase the D-dimer threshold to \u3c 0.89 μg./mL. to maintain their sensitivity to 100% and raise the specificity to 27.95%. Observing a D-dimer cut-off value of ≤ 1.28 μg./mL. would reduce sensitivity to 97.47% but increase the specificity to 57.93%. CONCLUSIONS: These study results support the utilization of alternative D-dimer thresholds to exclude PE in COVID-19 patients. Based on these findings, providers may be able to observe increased D-dimer cut-off values to reduce unnecessary pulmonary CT angiography scans

An Educational Intervention on the Clinical Utility of Point-Of-Care Ultrasound (POCUS) in the Timely Detection of Perioperative Thromboembolic Complications in COVID-19 Patients Undergoing Noncardiac Surgery

Background: Venous thromboembolism (VTE), including deep vein thrombosis (DVT) and pulmonary embolism (PE), is a rare but most likely fatal perioperative complication associated with increased patient morbidity and mortality. COVID-19-positive patients with VTE who present for surgery are predominantly asymptomatic and do not meet the conventional definition and traditional diagnostic criteria. This presents a challenge in identifying VTE in this patient population without proper surveillance and monitoring. Objectives: The purpose of this study is to improve anesthesia providers’ knowledge of the value of POCUS modality in preventing perioperative VTE in patients with COVID-19 undergoing noncardiac surgical procedures and improve recognition of associated risk factors that predispose patients to the development of VTE. Investigators used CINAHL, MEDLINE, and EMBASE databases to answer the PICO (i.e., population, intervention, comparison, outcome) question: “In the adult patients with COVID-19 (P), does the use of the POCUS modality as an adjunct to preoperative screening for DVT (I), compared to its non-use (C), improve the early identification of perioperative VTE ( O)? The literature review provides the educational framework to improve provider knowledge. The overall objective of the project is to increase the quality of healthcare delivery to improve healthcare outcomes for patients with COVID-19 undergoing noncardiac surgery. Methodology: The primary methodology of the proposed project is to administer an online educational intervention to providers which focuses on the benefits of perioperative POCUS utilization in the early identification of VTEs. Pre- and post-assessment surveys will be used to measure the improvement of provider knowledge before and after the intervention. Results: Overall, there was an improvement in provider knowledge following the education intervention. Additionally, the likelihood of utilizing the perioperative POCUS modality increased among anesthesia providers. Conclusion: The perioperative incorporation of the POCUS modality has been shown to accurately assess the presence of DVT. The educational intervention provided effectively improved anesthesia provider knowledge on the value of POCUS modality in preventing perioperative VTE in patients with COVID-19 undergoing noncardiac surgical procedures and improving recognition of associated risk factors that predispose patients to the development of these events. Increasing awareness of the high incidence of thromboembolic events in patients with COVID-19 and the role of POCUS in their early detection can reduce mortality and improve postoperative outcomes

Predictive Factors of Pulmonary Embolism in Older Patients with SARS-CoV-2: The OCTA-COVID-19 Study

Background: The risk of pulmonary embolism (PE) has not been studied in older patients affected by COVID-19. We aimed to assess PE incidence and risk factors in a population of older patients infected with SARS-CoV-2. Methods: An ambispective, observational cohort study. A total of 305 patients >= 75 years old had the SARS-CoV-2 infection from March to May 2020. The incidence rate of PE was estimated as the proportion of new cases within the whole sample. Youden's index was used to assess the cutoff point of D-dimer. To select factors associated with the risk of PE, time-to-event analyses were performed using cause-specific hazard models. Results: In total, 305 patients with a median age of 87 years (62.3% female) were studied; 67.9% were referred from nursing homes and 90.4% received any type of anticoagulation. A total of 64.9% showed frailty and 44% presented with dementia. The PE incidence was 5.6%. The cutoff value of a D-dimer level over 2.59 mg/L showed a sensitivity of 82.4% and specificity of 73.8% in discriminating a PE diagnosis. In the multivariate analysis, the factors associated with PE were previous oncological events and D-dimer levels. Conclusions: The PE incidence was 5.6%, and major risk factors for PE were oncological antecedents and increased plasma D-dimer levels.This work was partially supported by grants (to M.Q.-F., J.G.-P.) from the "New announcement for extraordinary initiative fund UAX-Santander COVID-19," Alfonso X el Sabio University