CT abnormalities 3 and 12 months after hospitalization for COVID-19 and association with disease severity: A prospective cohort study

OBJECTIVES

To investigate changes in chest CT between 3 and 12 months and associations with disease severity in patients hospitalized for COVID-19 during the first wave in 2020.

MATERIALS AND METHODS

Longitudinal cohort study of patients hospitalized for COVID-19 in 2020. Chest CT was performed 3 and 12 months after admission. CT images were evaluated using a CT severity score (CSS) (0-12 scale) and recoded to an abbreviated version (0-3 scale). We analyzed determinants of the abbreviated CSS with multivariable mixed effects ordinal regression.

RESULTS

242 patients completed CT at 3 months, and 124 (mean age 62.3±13.3, 78 men) also at 12 months. Between 3 and 12 months (n = 124) CSS (0-12 scale) for ground-glass opacities (GGO) decreased from median 3 (25th-75th percentile: 0-12) at 3 months to 0.5 (0-12) at 12 months (p<0.001), but increased for parenchymal bands (p<0.001). In multivariable analysis of GGO, the odds ratio for more severe abbreviated CSS (0-3 scale) at 12 months was 0.11 (95%CI 0.11 0.05 to 0.21, p<0.001) compared to 3 months, for WHO severity category 5-7 (high-flow oxygen/non-invasive ventilation/ventilator) versus 3 (non-oxygen use) 37.16 (1.18 to 43.47, p = 0.032), and for age ≥60 compared to <60 years 4.8 (1.33 to 17.6, p = 0.016). Mosaicism was reduced at 12 compared to 3 months, OR 0.33 (95%CI 0.16 to 0.66, p = 0.002).

CONCLUSIONS

GGO and mosaicism decreased, while parenchymal bands increased from 3 to 12 months. Persistent GGO were associated with initial COVID-19 severity and age ≥60 years.

A multi-institutional assessment of low-dose protocols in chest computed tomography: Dose and image quality

Background

Low-dose CT (LDCT) chest protocols have widespread clinical applications for many indications; as a result, there is a need for protocol assessment prior to standardization. Dalhousie University and Oslo Metropolitan University have a formally established cooperative relationship.

Purpose

The purpose is to assess radiation dose and image quality for LDCT chest protocols in seven different hospital locations in Norway and Canada.

Material and methods

Retrospective dosimetry data, volumetric CT dose index (CTDIvol), and dose length product (DLP) from 240 average-sized patients as well as CT protocol parameters were included in the survey. Effective dose (ED) and size-specific dose estimate (SSDE) were calculated for each examination. For a quantitative image quality analysis, noise, CT number, and signal-to-noise ratio (SNR) were determined for three regions in the chest. The contrast-to-noise ratio (CNR) was calculated for lung parenchyma in comparison to the subcutaneous fat. Differences in dose and image quality were evaluated by a single-factor ANOVA test. A two-sample t-test was performed to determine differences in means between individual scanners.

Results

The ANOVA test revealed significant differences (p < .05) in dose values for all scanners, including identical scanner models. Statistically significant differences (p < .05) were determined in mean values of the SNR distributions between the scanners in all three measured regions in the chest, as well as the CNR values.

Conclusion

The observed variations in dose and image quality measurements, even within the same hospitals and between identical scanner models, indicate a potential for protocol optimization in the involved hospitals in both countries.

Developing a Pan-European Technical Standard for a Comprehensive High-quality Lung Cancer CT Screening Program. An ERS Technical Standard

Screening for lung cancer with low radiation dose computed tomography (LDCT) has a strong evidence base. The European Council adopted a recommendation in November 2022 that lung cancer screening be implemented using a stepwise approach. The imperative now is to ensure that implementation follows an evidence-based process that delivers clinical and cost effectiveness. This ERS Taskforce was formed to provide a technical standard for a high-quality lung cancer screening program.

METHOD

A collaborative group was convened to include members of multiple European societies (see below). Topics were identified during a scoping review and a systematic review of the literature was conducted. Full text was provided to members of the group for each topic. The final document was approved by all members and the ERS Scientific Advisory Committee.

RESULTS

Ten topics were identified representing key components of a screening program. The action on findings from the LDCT were not included as they are addressed by separate international guidelines (nodule management and clinical management of lung cancer) and by a linked taskforce (incidental findings). Other than smoking cessation, other interventions that are not part of the core screening process were not included (e.g. pulmonary function measurement). Fifty-three statements were produced and areas for further research identified.

CONCLUSION

This European collaborative group has produced a technical standard that is a timely contribution to implementation of LCS. It will serve as a standard that can be used, as recommended by the European Council, to ensure a high quality and effective program.

The Effect of Magnesium Supplementation on Vascular Calcification in CKD: A Randomized Clinical Trial (MAGiCAL-CKD)

SIGNIFICANCE STATEMENT

Magnesium prevents vascular calcification in animals with CKD. In addition, lower serum magnesium is associated with higher risk of cardiovascular events in CKD. In a randomized, double-blinded, placebo-controlled trial, the authors investigated the effects of magnesium supplementation versus placebo on vascular calcification in patients with predialysis CKD. Despite significant increases in plasma magnesium among study participants who received magnesium compared with those who received placebo, magnesium supplementation did not slow the progression of vascular calcification in study participants. In addition, the findings showed a higher incidence of serious adverse events in the group treated with magnesium. Magnesium supplementation alone was not sufficient to delay progression of vascular calcification, and other therapeutic strategies might be necessary to reduce the risk of cardiovascular disease in CKD.

BACKGROUND

Elevated levels of serum magnesium are associated with lower risk of cardiovascular events in patients with CKD. Magnesium also prevents vascular calcification in animal models of CKD.

METHODS

To investigate whether oral magnesium supplementation would slow the progression of vascular calcification in CKD, we conducted a randomized, double-blinded, placebo-controlled, parallel-group, clinical trial. We enrolled 148 subjects with an eGFR between 15 and 45 ml/min and randomly assigned them to receive oral magnesium hydroxide 15 mmol twice daily or matching placebo for 12 months. The primary end point was the between-groups difference in coronary artery calcification (CAC) score after 12 months adjusted for baseline CAC score, age, and diabetes mellitus.

RESULTS

A total of 75 subjects received magnesium and 73 received placebo. Median eGFR was 25 ml/min at baseline, and median baseline CAC scores were 413 and 274 in the magnesium and placebo groups, respectively. Despite plasma magnesium increasing significantly during the trial in the magnesium group, the baseline-adjusted CAC scores did not differ significantly between the two groups after 12 months. Prespecified subgroup analyses according to CAC>0 at baseline, diabetes mellitus, or tertiles of serum calcification propensity did not significantly alter the main results. Among subjects who experienced gastrointestinal adverse effects, 35 were in the group receiving magnesium treatment versus nine in the placebo group. Five deaths and six cardiovascular events occurred in the magnesium group compared with two deaths and no cardiovascular events in the placebo group.

CONCLUSIONS

Magnesium supplementation for 12 months did not slow the progression of vascular calcification in CKD, despite a significant increase in plasma magnesium.

CLINICAL TRIALS REGISTRATION

www.clinicaltrials.gov ( NCT02542319 ).

A prospective study of pulmonary outcomes and chest computed tomography in the first year after COVID-19

COVID-19 primarily affects the respiratory system. We aimed to evaluate how pulmonary outcomes develop after COVID-19 by assessing participants from the first pandemic wave prospectively 3 and 12 months following hospital discharge. Pulmonary outcomes included self-reported dyspnoea assessed with the modified Medical Research Council dyspnoea scale, 6-min walk distance (6MWD), spirometry, diffusing capacity of the lung for carbon monoxide (D _LCO), body plethysmography and chest computed tomography (CT). Chest CT was repeated at 12 months in participants with pathological findings at 3 months. The World Health Organization (WHO) ordinal scale for clinical improvement defined disease severity in the acute phase. Of 262 included COVID-19 patients, 245 (94%) and 222 (90%) participants attended the 3- and 12-month follow-up, respectively. Self-reported dyspnoea and 6MWD remained unchanged between the two time points, while D _LCO and total lung capacity improved (0.28 mmol·min^-1·kPa^-1, 95% CI 0.12-0.44, and 0.13 L, 95% CI 0.02-0.24, respectively). The prevalence of fibrotic-like findings on chest CT at 3 and 12 months in those with follow-up chest CT was unaltered. Those with more severe disease had worse dyspnoea, D _LCO and total lung capacity values than those with mild disease. There was an overall positive development of pulmonary outcomes from 3 to 12 months after hospital discharge. The discrepancy between the unaltered prevalence of self-reported dyspnoea and the improvement in pulmonary function underscores the complexity of dyspnoea as a prominent factor of long-COVID. The lack of increase in fibrotic-like findings from 3 to 12 months suggests that SARS-CoV-2 does not induce a progressive fibrotic process in the lungs.

Low diffusion capacity of the lung predicts pneumothorax and chest drainage after CT-guided lung biopsy

OBJECTIVES

Complications after CT-guided lung biopsy is a burden both for the individual patient and for the overall healthcare. Pneumothorax is the most common complication. This study determined the association between lung function tests and pneumothorax and chest drainage following CT-guided lung biopsy in consecutive patients in a large university hospital.

RESULTS

We prospectively registered 875 biopsy procedures from 786 patients in one institution from January 27th 2012 to March 1st 2017 and recorded complications including pneumothorax with or without chest drainage. Lung function data from 637 patients undergoing 710 of the procedures were available. The association of lung function measures with pneumothorax with or without chest drainage was assessed using multivariable logistic regression analyses. Diffusion capacity for carbon monoxide (DLCO) below 4.70 mmol/min/kPa was associated with increased occurrence of pneumothorax and chest drainage after CT guided lung biopsy. We found no association between FEV₁, RV and occurrence of pneumothorax and chest drainage. We found low DLCO to be a risk factor of pneumothorax and chest drainage after CT-guided lung biopsy. This should be taken into account in planning and performing the procedure.

Diagnostic yield, complications, pathology and anatomical features in CT-guided percutaneous needle biopsy of mediastinal tumours

OBJECTIVES

This study presents the experiences of percutaneous CT-guided needle biopsy at a university hospital in Norway.

METHODS

A retrospective examination of all mediastinal biopsy procedures between April 2015 and August 2019 was performed at Akershus University Hospital in Norway. We registered patient and procedure characteristics, along with lesion pathology and characteristics including localization according to anatomical and Felson mediastinal compartments.

RESULTS

The study included 48 procedures, conducted in 45 patients (29 men and 16 women) with a mean age of 60,5 years. Pneumothorax occurred in 12 procedures (60% of the transpulmonary procedures) and pneumomediastinum in 18 procedures (38%). Pneumothorax was only seen in procedures with transpulmonal access. Four of the pneumothorax cases required pleural drainage. Diagnostic yield was 96%. We found significant (p = 0,006), moderate to high association between anatomical compartment localization and histopathological diagnosis (Cramér's V = 0,49) for tumours selected for CT-guided percutaneous biopsy. Felson's compartment division on the other hand, did not show any significant associations.

CONCLUSION

We found CT-guided percutaneous needle biopsy of mediastinal tumours to be an effective and safe procedure with a diagnostic yield of 96%. The main complications were pneumothorax and pnumomediastinum, with a relatively low chest drainage rate. Anatomical mediastinum compartment showed a significant, moderate to high association with the histopathological diagnosis for tumours selected for percutaneous CT-guided biopsies, where most malignancies were seen in the anterior compartment.

Indirect CT venography of the lower extremities: impact of scan delay and patient factors on contrast enhancement and examination quality

OBJECTIVES

Indirect computed tomography venography (CTV) is often the next imaging modality for deep vein thrombosis (DVT) when sonography is inconclusive. Our aim was to investigate the impact of scan delay and patient factors on contrast enhancement (CE) and examination quality in CTV.

METHODS

Patients with clinical suspicion or clinical mimics of DVT in one large hospital were enrolled. Age, sex, body weight, height, heart rate, systolic blood pressure and cardiac output were registered. CTV of the popliteal veins was obtained at 30 s intervals at 30-210 s delays. The proportions of examinations with CE exceeding predefined cut-offs were estimated and subjective examination quality was rated. Changes in CE with time, and associations between patient factors and time to peak contrast enhancement (TPCE) were modelled with mixed effects non-linear and linear regression, respectively.

RESULTS

The CE increased with increasing scan delay and reached a plateau from 120 to 210 s. The percentages of examinations achieving enhancement above cut-offs across all thresholds from 70 to 100 HU were higher at 120 s compared to 90 s (p < 0.001). After 120 s, there were no differences across scan delays for any thresholds. No patient factors showed a significant effect on TPCE. The percentage of examinations rated as acceptable was higher at 120 s compared to 90 s (p < 0.001). After 120 s, there were no statistically significant differences across scan delays.

CONCLUSIONS

No patient factors were associated with TPCE in CTV. A fixed scan delay of 120-210 s yielded the best examination quality.

KEY POINTS

• Contrast enhancement reached a plateau at scan delay between 90 and 120 s. • A scan delay of 120-210 s yielded the best examination quality. • No patient factors were associated with time to peak contrast enhancement.

1358 Does A COVID Protected Hospital Within A COVID Hospital Enable Elective Care and Training Opportunities?

Introduction

Elective care in the UK came to a standstill with the advent of the COVID-19 pandemic. A restart could only be enabled with ‘green site’ separation and a ‘covid protected’ zone. A ‘hospital within the hospital’ concept was developed including 9 elective theatres, 28 ring fenced elective beds, a surgical enhanced care unit, a canteen, and a separated entrance. This model was underpinned with PPE, enhanced infection control and guidance for staff. The study documented the ability to recover elective activity and therefore provide a training environment for surgical trainees.

Method

Data was collected weekly (7/20 to 1/21) through the business informatics system with regard to theatres cases completed compared to the activity achieved in the 11-theatre elective estate pre COVID-19.

Results

Pre COVID-19, an average of 263 cases were completed per week. In the first week of operation, 31% of theatre capacity was achieved. By week 7, 106% of pre COVID was recorded and 130% by week 11. This was maintained until the impact of the second wave where activity has reduced to 50% but is not anticipated to reduce further as local anaesthetic and blocks maybe utilised.

Conclusions

This ‘hospital within the hospital’ has enabled elective care to return to above normal levels, with increased efficiencies. This has enabled a rapid return to a training environment for trainees disheartened with deployment to critical care in the first wave.

845 Diabetic Foot Care Services in COVID-19 Era – A University Hospital Multi specialty Team Experience

Introduction

Multidisciplinary foot care services contribute to the reduction in amputations from foot ulceration secondary to diabetes. The COVID-19 pandemic pressurised services and required a pause of elective care. This study reports the patient’s experience of foot care provision during the first wave where self-care, virtual appointments and patient directed appointments were utilised.

Method

Diabetic foot patients were retrospectively identified over a one-month period booked for MDT care (in hospital, OPD, diabetic foot clinic, community podiatry clinic or at home). All patients&gt;16 years of age diagnosed with a new or previous diabetic foot ulcer or post-operative foot wound were included. Data was collated via a patient survey form and descriptive statistics were used to characterize the study population and responses.

Results

63 patients were identified (1/10 – 30/10) with data collated from 51 respondents (81%). 78% (40/51) were male. Median age was 69 years (IQR 59–76). 86% were comfortable attending a hospital appointment. 92% reported continuing to receive an appropriate level of care. All of the patients felt well supported and knew how to access the foot care service. 29% utilised virtual care. 82% (42/51) considered face to face appointments were more suitable for follow up rather than virtual/phone appointments.

Conclusions

It was possible to continue to provide safe diabetic foot care despite the COVID-19 pandemic but careful patient selection and communication is the key.

837 The Identification of Gaze Behaviour and Physiological Markers Associated With Making An Error During Laparoscopic Cholecystectomy

Introduction

Adverse surgical events remain at an unacceptably high level despite multiple global safety initiatives being introduced. As yet, however there is no conclusive evidence to identify whether physiological markers can be used to predict whether a surgeon will make an error

Method

Surgeons were asked to complete a simulated laparoscopic cholecystectomy task while physiological metrics and gaze behaviour was tracked. LightGBM and CatBoost were used to predict the physiological metric most useful in predicting whether a surgeon was about to make an error. The binary task used a boolean value of “does an error occur in the next 5 seconds” as the dependent variable, while the multiclass task classified the severity of error (0, 1, 2, 3).

Results

Autocorrelation with lag (eventually calculated with a lag of timestep 2) measured the tendency of this timeseries to correlate with itself. The degree of correlation, or lack of correlation, and sudden changes in correlation over time were gleaned from this feature.

Conclusions

Skin conductance was most likely to successfully predict impending error. However when gaze features were added, overall model performance improved by 6.4%. The potential for reduction in surgical error rate and improvement in patient safety are important factors to consider.

Dyspnoea, lung function and CT findings 3 months after hospital admission for COVID-19

The long-term pulmonary outcomes of coronavirus disease 2019 (COVID-19) are unknown. We aimed to describe self-reported dyspnoea, quality of life, pulmonary function and chest computed tomography (CT) findings 3 months following hospital admission for COVID-19. We hypothesised outcomes to be inferior for patients admitted to intensive care units (ICUs), compared with non-ICU patients.

Discharged COVID-19 patients from six Norwegian hospitals were enrolled consecutively in a prospective cohort study. The current report describes the first 103 participants, including 15 ICU patients. The modified Medical Research Council (mMRC) dyspnoea scale, the EuroQol Group's questionnaire, spirometry, diffusing capacity of the lung for carbon monoxide (D_LCO), 6-min walk test, pulse oximetry and low-dose CT scan were performed 3 months after discharge.

mMRC score was >0 in 54% and >1 in 19% of the participants. The median (25th–75th percentile) forced vital capacity and forced expiratory volume in 1 s were 94% (76–121%) and 92% (84–106%) of predicted, respectively. D_LCO was below the lower limit of normal in 24% of participants. Ground-glass opacities (GGO) with >10% distribution in at least one of four pulmonary zones were present in 25% of participants, while 19% had parenchymal bands on chest CT. ICU survivors had similar dyspnoea scores and pulmonary function as non-ICU patients, but higher prevalence of GGO (adjusted OR 4.2, 95% CI 1.1–15.6) and lower performance in usual activities.

3 months after admission for COVID-19, one-fourth of the participants had chest CT opacities and reduced diffusing capacity. Admission to ICU was associated with pathological CT findings. This was not reflected in increased dyspnoea or impaired lung function.

3 months after discharge, a quarter of COVID-19 survivors have reduced gas diffusion capacity and persistent parenchymal opacities. ICU treatment is associated with persistent parenchymal opacities, but not with dyspnoea or reduced diffusing capacity.https://bit.ly/2J3xH4x

Antiviral activities of Cholistani plants against common poultry viruses

Herbal medicines are becoming more popular and acceptable day by day due to their effectiveness, limited side effects, and cost-effectiveness. Cholistani plants are reported as a rich source of antibacterial, antifungal, antiprotozoal, antioxidant, and anticancer agents. The current study has evaluated antiviral potential of selected Cholistani plants. The whole plants were collected, ground and used in extract formation with n-hexane, ethyl acetate and n-butanol. All the extracts were concentrated by using a rotary evaporator and concentrate was finally dissolved in an appropriate vol of the same solvent. All of the extracts were tested for their antiviral potential by using 9-11 days old chick embryonated eggs. Each extract was tested against the Avian Influenza virus H9N2 strain (AIV), New Castle Disease virus Lasoota strain (NDV), Infectious bronchitis virus (IBV) and an Infectious bursal disease virus (IBDV). Hemagglutination test (HA) and Indirect Hemagglutination (IHA) tests were performed for different viruses. The overall order of the antiviral potential of Cholistani plants against viruses was NDV>IBV>IBDV>AIV. In terms of antiviral activity from extracts, the order of activity was n-butanol>ethyl acetate>n-hexane. The medicinal plants Achyranthes aspera, Neuroda procumbens, Panicum antidotale, Ochthochloa compressa and Suaeda fruticose were very effective against all four poultry viruses through their extracts. The low IC50 values of these extracts confirm the high antiviral potential against these viruses. It is worth to mention that Achyranthes aspera was found positive against IBDV through all its extracts which overcome the problem of unavailability of any known drug against IBDV. In short, the study proved that Cholistani plants are rich source of antiviral agent and their extracts can be used as good source of antiviral drugs both in crude and in purified form.

P473Safety and efficacy of direct oral anticoagulants compared to vitamin K antagonists in patients with atrial fibrillation undergoing percutaneous coronary interventions: A meta-analysis

Background

 Coronary artery disease (CAD) and atrial fibrillation (AF) are commonly associated. Co-treatment with multiple anti-thrombotic agents can increase the risk of bleeding.

Purpose

We sought to evaluate patient-centered outcomes in patients with AF on double therapy with direct oral anticoagulants (DOACs) compared to patients with standard triple therapy, [a vitamin K antagonist (VKA) plus dual antiplatelet therapy].

Methods

We performed an extensive systematic review of the literature and meta-analysis of randomized controlled trials reporting outcomes of patients receiving double therapy with DOACs compared to triple therapy with VKAs in patients with AF undergoing percutaneous coronary intervention (PCI). Patient-centered outcomes were the International Society of Thrombosis and Hemostasis (ISTH) major or clinically relevant non-major bleeding (CRNB), all-cause mortality, major adverse cardiovascular events (MACE), myocardial infarction, stent thrombosis, and stroke.

Results

Four randomized controlled trials (9602 patients) met our inclusion criteria. Compared to VKAs, DOACs were associated with significantly lower ISTH major bleeding/ CRNB (RR - 0.75, 95% CI: 0.67-0.82, p &lt; 0.00001, I2 = 11%). There were no statistically significant differences in the efficacy outcomes, including myocardial infarction (RR- 0.99, 95% CI :0.79-1.25, p = 0.96, I2 = 0%), stent thrombosis (RR - 0.97, 95% CI: 0.6-1.55, p = 0.89, I2 = 0%), ischemic stroke (RR - 0.76, 95% CI: 0.5-1.15, p = 0.19, I2 = 0%), all-cause mortality (RR - 1.06, 95% CI: 0.85-1.31, p = 0.61, I2 = 0%) and MACE (RR - 1.06, 95% CI: 0.91-1.22, p = 0.97, I2 = 0%).

Conclusion

Compared with triple therapy with VKAS, double therapy with DOACs is associated with a reduced risk of bleeding and is as effective in patients with AF undergoing PCI.

Abstract Figure.

Increased respiratory morbidity in individuals with interstitial lung abnormalities

Background

Interstitial lung abnormalities (ILA) are common in participants of lung cancer screening trials and broad population-based cohorts. They are associated with increased mortality, but less is known about disease specific morbidity and healthcare utilisation in individuals with ILA.

Methods

We included all participants from the screening arm of the Danish Lung Cancer Screening Trial with available baseline CT scan data (n = 1990) in this cohort study. The baseline scan was scored for the presence of ILA and patients were followed for up to 12 years. Data about all hospital admissions, primary healthcare visits and medicine prescriptions were collected from the Danish National Health Registries and used to determine the participants’ disease specific morbidity and healthcare utilisation using Cox proportional hazards models.

Results

The 332 (16.7%) participants with ILA were more likely to be diagnosed with one of several respiratory diseases, including interstitial lung disease (HR: 4.9, 95% CI: 1.8–13.3, p = 0.008), COPD (HR: 1.7, 95% CI: 1.2–2.3, p = 0.01), pneumonia (HR: 2.0, 95% CI: 1.4–2.7, p <  0.001), lung cancer (HR: 2.7, 95% CI: 1.8–4.0, p <  0.001) and respiratory failure (HR: 1.8, 95% CI: 1.1–3.0, p = 0.03) compared with participants without ILA. These findings were confirmed by increased hospital admission rates with these diagnoses and more frequent prescriptions for inhalation medicine and antibiotics in participants with ILA.

Conclusions

Individuals with ILA are more likely to receive a diagnosis and treatment for several respiratory diseases, including interstitial lung disease, COPD, pneumonia, lung cancer and respiratory failure during long-term follow-up.