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.

Comparison of gaze behaviour of trainee and experienced surgeons during laparoscopic gastric bypass

Background

Eye tracking presents a novel tool that could be used to profile skill levels in surgery objectively. The primary aim of this study was to identify differences in gaze behaviour between expert and junior surgeons performing a laparoscopic Roux-en-Y gastric bypass (LRYGB) for obesity.

Methods

This prospective observational study used a lightweight eye-tracking apparatus to determine the difference in gaze behaviours between expert (more than 75 procedures) and junior (75 or fewer procedures) surgeons at defined stages of LRYGB. Primary endpoints were normalized dwell time and fixation frequency. Secondary endpoints were blink rate, maximum pupil size and rate of pupil change.

Results

A total of 20 procedures (12 junior, 8 expert) were analysed. Compared with juniors, experts showed a prolonged dwell time on the screen during angle of His dissection (median (range) 91·20 (83·40–94·40) versus 68·95 (59·80–87·60) per cent; P = 0·001), formation of the retrogastric tunnel (91·50 (85·80–95·50) versus 73·60 (34·60–90·50) per cent; P = 0·001) and gastric pouch formation (86·95 (83·60–90·20) versus 67·60 (37·10–80·00) per cent P &lt; 0·001). Juniors had a greater blink frequency throughout all recorded segments (P &lt; 0·010) and had a larger maximum pupil size during all recorded operative segments (P &lt; 0·010). Rate of pupil change was greater in juniors in all analysed segments (P &lt; 0·010).

Conclusion

These results suggest that experts display more focused attention on significant stimuli, alongside experiencing a reduced mental workload and having increased concentration. This has the potential for future use in validation of surgical skill in high-stakes assessment.

Implementation of lung cancer CT screening in the Nordic countries

INTRODUCTION

We review the current knowledge of CT screening for lung cancer and present an expert-based, joint protocol for the proper implementation of screening in the Nordic countries.

MATERIALS AND METHODS

Experts representing all the Nordic countries performed literature review and concensus for a joint protocol for lung cancer screening.

RESULTS AND DISCUSSION

Areas of concern and caution are presented and discussed. We suggest to perform CT screening pilot studies in the Nordic countries in order to gain experience and develop specific and safe protocols for the implementation of such a program.

Computer tomography guided lung biopsy using interactive breath-hold control: a randomized study

BACKGROUND

Interactive breath-hold control (IBC) may improve the accuracy and decrease the complication rate of computed tomography (CT)-guided lung biopsy, but this presumption has not been proven in a randomized study.

METHODS

Patients admitted for CT-guided lung biopsy were randomized to biopsy either with (N=201) or without (N=206) IBC. Biopsy accuracy, procedure time, radiation, and complications were compared in the two groups. Predictors for pneumothorax were analyzed.

RESULTS

Procedures performed with the use of IBC (N=130) did not show higher biopsy accuracy (P=0.979) but were associated with a higher risk of pneumothorax (P=0.022) compared to procedures without the use of IBC (N=171). Overall, 50% of the biopsies were malignant, 13% were benign, and 33% were inconclusive (4% missing). Long needle time (P=0.037) and small nodule size (P=0.001) were predictors of pneumothorax.

CONCLUSIONS

The use of IBC for CT-guided lung biopsy was not an advantage for unselected patients in our care, since it did not improve the biopsy accuracy and the risk of pneumothorax was increased.

Elevated d-dimer cut-off values for computed tomography pulmonary angiography-d-dimer correlates with location of embolism

BACKGROUND

Acute pulmonary embolism (APE) is a potentially fatal condition, and making a timely diagnosis can be challenging. Computed tomography pulmonary angiography (CTPA) has become the modality of choice, and this contributes to the increasing load on emergency room CT scanners. Our purpose was to investigate whether an elevated d-dimer cut-off could reduce the demand for CTPA while maintaining a high sensitivity and negative predictive value (NPV).

METHODS

We retrospectively reviewed all patients referred for CTPA with suspicion of APE in 2012, and collected d-dimer values and CTPA results. We investigated the diagnostic performance of d-dimer using a 0.5 mg/L cut-off and an age adjusted cut-off. We also evaluated a new and elevated cut-off. Cases were categorized according to their CTPA result into: no embolism, peripheral embolism, lobar embolism and central embolism. Finally we investigated a possible correlation between d-dimer values and location of embolism.

RESULTS

We included 1,051 CTPAs, from which 216 (21%) showed pulmonary embolism. There were concomitant d-dimer analyses in 822 CTPA examinations. The current 0.5 mg/L cut-off achieved a sensitivity and NPV of 99%. The age-adjusted cut-off achieved a sensitivity and NPV of 98%, and our suggested cut-off of 0.9 mg/L achieved a sensitivity and NPV of 97%.

CONCLUSIONS

We conclude that the elevated d-dimer cut-off of 0.9 mg/L achieved a high sensitivity and NPV, while reducing the number of CTPA by 27%. The correlation between d-dimer values and location of embolisms supports the suggestion of an elevated d-dimer value.

Implementation and organization of lung cancer screening

CT screening for lung cancer is now being implemented in the US and China on a widespread national scale but not in Europe so far. The review gives a status for the implementation process and the hurdles to overcome in the future. It also describes the guidelines and requirements for the structure and components of high quality CT screening programs. These are essential in order to achieve a successful program with the fewest possible harms and a possible mortality benefit like that documented in the American National Lung Screening Trial (NLST). In addition the importance of continued research in CT screening methods is described and discussed with focus on the great potential to further improve this method in the future for the benefit of patients and society.

Smoking cessation and lung cancer screening

Smoking behavior may have a substantial influence on the overall effect of lung cancer screening. Non-randomized studies of smoking behavior during screening have indicated that computer tomography (CT) screening induces smoking cessation. Randomized studies have further elaborated that this effect has to do with participation in screening alone and not dependent on the CT scan. Participants in both CT and control arm in randomized screening trials had higher smoking abstinence rate compared to that of the general population. A positive screening test seems to further promote smoking cessation and decrease smoking relapse rate. Also low smoking dependency and high motivation to quit smoking at baseline predicted smoking abstinence in screening trials. Lung cancer screening therefore seems to be a teachable moment for smoking cessation. Targeted smoking cessation counselling should be an integrated part of future lung cancer screening trials.

A rare missense mutation in CHRNA4 associates with smoking behavior and its consequences

Using Icelandic whole-genome sequence data and an imputation approach we searched for rare sequence variants in CHRNA4 and tested them for association with nicotine dependence. We show that carriers of a rare missense variant (allele frequency=0.24%) within CHRNA4, encoding an R336C substitution, have greater risk of nicotine addiction than non-carriers as assessed by the Fagerstrom Test for Nicotine Dependence (P=1.2 × 10(-4)). The variant also confers risk of several serious smoking-related diseases previously shown to be associated with the D398N substitution in CHRNA5. We observed odds ratios (ORs) of 1.7-2.3 for lung cancer (LC; P=4.0 × 10(-4)), chronic obstructive pulmonary disease (COPD; P=9.3 × 10(-4)), peripheral artery disease (PAD; P=0.090) and abdominal aortic aneurysms (AAAs; P=0.12), and the variant associates strongly with the early-onset forms of LC (OR=4.49, P=2.2 × 10(-4)), COPD (OR=3.22, P=2.9 × 10(-4)), PAD (OR=3.47, P=9.2 × 10(-3)) and AAA (OR=6.44, P=6.3 × 10(-3)). Joint analysis of the four smoking-related diseases reveals significant association (P=6.8 × 10(-5)), particularly for early-onset cases (P=2.1 × 10(-7)). Our results are in agreement with functional studies showing that the human α4β2 isoform of the channel containing R336C has less sensitivity for its agonists than the wild-type form following nicotine incubation.

Ground-Glass Opacity Lung Nodules in the Era of Lung Cancer CT Screening: Radiology, Pathology, and Clinical Management

The advent of computed tomography screening for lung cancer will increase the incidence of ground-glass opacity (GGO) nodules detected and referred for diagnostic evaluation and management. GGO nodules remain a diagnostic challenge; therefore, a more systematic approach is necessary to ensure correct diagnosis and optimal management. Here we present the latest advances in the radiologic imaging and pathology of GGO nodules, demonstrating that radiologic features are increasingly predictive of the pathology of GGO nodules. We review the current guidelines from the Fleischner Society, the National Comprehensive Cancer Network, and the British Thoracic Society. In addition, we discuss the management and follow-up of GGO nodules in the light of experience from screening trials. Minimally invasive tissue biopsies and the marking of GGO nodules for surgery are new and rapidly developing fields that will yield improvements in both diagnosis and treatment. The standard-of-care surgical treatment of early lung cancer is still minimally invasive lobectomy with systematic lymph node dissection. However, recent research has shown that some GGO lesions may be treated with sublobar resections; these findings may expand the surgical treatment options available in the future.

[Lung cancer screening with low-dose CT - Danish and international results]

Lung cancer is the cancer type that causes the largest number of deaths in Denmark. With advances in medical imaging and widespread use of computed tomography (CT), it is possible to detect even small abnormalities in lung tissue. This has led to a great interest in lung cancer screening with low-dose CT and launching of randomised screening trials worldwide. This paper gives an overview of the current lung cancer screening trials in Denmark and internationally and focuses on main lung cancer findings and mortality results.

[Lung cancer screening with low dose CT requires careful consideration]

Results from the American National Lung Screening Trial (NLST) show a significant reduction in lung cancer and all-cause mortality in a high risk population screened with annual low-dose CT. Handling of pulmonary nodules, false positive tests, overdiagnosis, psychosocial consequences and cost-efficiency etc. are all aspects that require careful consideration. This paper gives an overview of the current knowledge on these issues. Before a recommendation can be made, we need an overall evaluation of both the benefits and harms in CT screening for lung cancer.

The cycle characteristics of clomiphene with clomiphene and menotropins in polycystic ovary syndrome and non polycystic ovary syndrome infertile patients

AIM

This study compares the cycle characteristics of clomiphene (CC) with CC+HMG (Human Menopausal Gonadotropin or Menotropins) in Polycystic Ovary Syndrome (PCOS) and non-PCOS infertile patients.

METHODS

Patients were treated by CC + minimal HMg protocol. The cancellation rate, the mean number of different follicle sizes and endometrial thickness and pattern were compared.

RESULTS

The cancelled cycles due to non-responsiveness were significantly higher in CC compared to CC+ minimal HMg protocol. PCOS patients are significantly nonresponsive in CC cycle and hyperresponsive in CC+ minimal HMg cycles. The mean number of different sizes of follicles and the endometrial thickness were significantly higher in CC+ minimal HMg. PCOS patients were significantly different from non-PCOS regarding the number of mature follicle and endometrial thickness. The pregnancy rate was 11% (10.2% in non-PCOS and 12.2% in PCOS).

CONCLUSION

CC+ minimal HMg is a viable alternative to HMg /FSH only protocol in CC failure or resistant patients, and its efficacy can be mostly attributed to improvement of endometrial quality and increase in follicle number. Moreover, due to high cancellation of PCOS patients treated by this protocol, seemingly other alternatives should be found; perhaps sequential letrozole+HMg/FSH that have been shown to improve the ovarian response in this group of patients.

Relationship between chronic obstructive pulmonary disease and subclinical coronary artery disease in long-term smokers

AIMS

Cardiovascular conditions are reported to be the most frequent cause of death in patients with chronic obstructive pulmonary disease (COPD). However, it remains unsettled whether severity of COPD per se is associated with coronary artery disease (CAD) independent of traditional cardiovascular risk factors. The aim of this study was to examine the relationship between the presence and severity of COPD and the amount of coronary artery calcium deposit, an indicator of CAD and cardiac risk, in a large population of current and former long-term smokers.

METHODS AND RESULTS

In this cross-sectional study, long-term smokers without clinically manifested CAD were recruited from the Danish Lung Cancer Screening Trial and classified according to lung function by the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria. Coronary artery calcium deposit as a measure of subclinical CAD and cardiac risk was evaluated with multi detector computed tomography and the Agatston coronary artery calcium score (CACS). Participants were categorized into five CACS risk classification groups according to the CACS. The population (n = 1535) consisted of 41% participants without COPD, 28% with mild, and 31% with moderate-to-severe COPD (n = 46 with severe COPD). In addition to age, male gender, hypertension, hypercholesterolaemia, and continued smoking, COPD according to GOLD classification were independent predictors of a higher CACS risk classification group in multivariable analysis [odds ratio (OR): 1.28 (1.01-1.63) and OR: 1.32 (1.05-1.67), for mild and moderate-to-severe COPD, respectively, compared with no COPD].

CONCLUSION

COPD in long-term smokers is independently correlated with the CACS, while COPD severity per se does not show a dose-response relationship.

Lidocaine Cyclodextrin complex Ophthalmic Drop, a New Topical Anesthetic Choice

BACKGROUND

Topical anesthesia is a safe and cost-effective method considered as the first-choice in many procedures. Due to the physiological characteristics of eye, most of the local anesthetics cannot efficiently penetrate through the conjunctiva deep to tenon. The aim of this pilot study was to find a new form of lidocaine to give a sufficient level of anesthesia.

METHODS

Lidocaine Cyclodextrin complex ophthalmic drop was produced and its pharmacological properties were studied [tested] in standard temperature and pressure. 30 patients (18 males, 12 females) with the mean age of 30.68±8.02 years enrolled in this clinical trial. All the patients were fully informed and signed the ethics committee consent forms. The patients were given tetracaine drop as the anesthetic: 3 drops separated 2 minute apart 10 min before the intervention. If we achieved a sufficient level of anesthesia, the procedure was done after. If the patient could not tolerate the procedure, the method was changed to lidocaine drop (administered after wash-out period like the first drop).The last option was conventional injection method if the patient could not tolerate the procedure with the second method either.We used this type of anesthesia for conventional procedures such as forced duction test, symblepharon, pterygium, and disport injection into extra-ocular muscles. All the procedures were done by one surgeon in a university hospital. We used a 0 to 10 visual analogue scale for pain and two 0 to 4 patient and physician satisfaction scales designed for this study.

RESULTS

The mean pain score was 7.53±0.90 in group 1 and 3.03±1.83 in group 2 (P=0.00). Patient and surgeon satisfaction in group 1 were 1.33±0.48 and 1.40±0.56 respectively; while 3.23±1.00 and 3.56±0.77 for group 2 (P=0.00). Tetracaine drop could not induce sufficient anesthesia for none of the patients. Cyclodextrin based lidocaine drop was successful except For two patients for whom we changed the anesthesia to Sub-conjunctival injection method.

CONCLUSION

Our newly manufactured cyclodextrin based lidocaine eye drop could successfully induce sufficient anesthesia for 28 of 30 patients. Further studies with larger sample sizes are now being designed to find more clinical evidence about this method.

CT screening for lung cancer brings forward early disease. The randomised Danish Lung Cancer Screening Trial: status after five annual screening rounds with low-dose CT

BACKGROUND

The effects of low-dose CT screening on disease stage shift, mortality and overdiagnosis are unclear. Lung cancer findings and mortality rates are reported at the end of screening in the Danish Lung Cancer Screening Trial.

METHODS

4104 men and women, healthy heavy smokers/former smokers were randomised to five annual low-dose CT screenings or no screening. Two experienced chest radiologists read all CT scans and registered the location, size and morphology of nodules. Nodules between 5 and 15 mm without benign characteristics were rescanned after 3 months. Growing nodules (>25% volume increase and/or volume doubling time<400 days) and nodules >15 mm were referred for diagnostic workup. In the control group, lung cancers were diagnosed and treated outside the study by the usual clinical practice.

RESULTS

Participation rates were high in both groups (screening: 95.5%; control: 93.0%; p<0.001). Lung cancer detection rate was 0.83% at baseline and mean annual detection rate was 0.67% at incidence rounds (p=0.535). More lung cancers were diagnosed in the screening group (69 vs. 24, p<0.001), and more were low stage (48 vs 21 stage I-IIB non-small cell lung cancer (NSCLC) and limited stage small cell lung cancer (SCLC), p=0.002), whereas frequencies of high-stage lung cancer were the same (21 vs 16 stage IIIA-IV NSCLC and extensive stage SCLC, p=0.509). At the end of screening, 61 patients died in the screening group and 42 in the control group (p=0.059). 15 and 11 died of lung cancer, respectively (p=0.428).

CONCLUSION

CT screening for lung cancer brings forward early disease, and at this point no stage shift or reduction in mortality was observed. More lung cancers were diagnosed in the screening group, indicating some degree of overdiagnosis and need for longer follow-up.

Texture-based analysis of COPD: a data-driven approach

This study presents a fully automatic, data-driven approach for texture-based quantitative analysis of chronic obstructive pulmonary disease (COPD) in pulmonary computed tomography (CT) images. The approach uses supervised learning where the class labels are, in contrast to previous work, based on measured lung function instead of on manually annotated regions of interest (ROIs). A quantitative measure of COPD is obtained by fusing COPD probabilities computed in ROIs within the lung fields where the individual ROI probabilities are computed using a k nearest neighbor (kNN ) classifier. The distance between two ROIs in the kNN classifier is computed as the textural dissimilarity between the ROIs, where the ROI texture is described by histograms of filter responses from a multi-scale, rotation invariant Gaussian filter bank. The method was trained on 400 images from a lung cancer screening trial and subsequently applied to classify 200 independent images from the same screening trial. The texture-based measure was significantly better at discriminating between subjects with and without COPD than were the two most common quantitative measures of COPD in the literature, which are based on density. The proposed measure achieved an area under the receiver operating characteristic curve (AUC) of 0.713 whereas the best performing density measure achieved an AUC of 0.598. Further, the proposed measure is as reproducible as the density measures, and there were indications that it correlates better with lung function and is less influenced by inspiration level.

Optimal wrist angulation shortens time needed for radial artery catheterization: a prospective, randomized, and blinded study

INTRODUCTION

Optimal wrist position is essential for successful catheterization of the radial artery. We planned to study the success rate of radial artery catheterization at various degrees of wrist extension angulations.

METHODS

This prospective, randomized study was performed in 60 consenting patients aged between 18-65 years and undergoing variable surgeries where the anesthetic management required an arterial catheterization. All patients were randomized into three groups of 20 patients each, according to wrist angulation during radial artery catheterization : either 30 degrees (Group 30), 45 degrees (Group 45), or 60 degrees (Group 60). Three metallic angulated wrist boards with angles of 30 degrees, 45 degrees, and 60 degrees (angle measured with calipers) were prepared, on which patient's wrist was kept at the above-mentioned angles of extension. Radial artery catheterization success rate, catheterization time, and numbers of attempts were recorded.

RESULTS

The catheterization time was minimal in group 45 (30.50 +/- 16.82 sec) as compared to 36.00 +/- 14.19 sec and 43.50 +/- 13.80 sec in group 30 and 60, respectively. Radial artery was catheterized at first attempt in 60% of Group 45 and Group 60 patients, and in 50% of Group 30 patients. The arterial catheterization was successful in 14/20 patients in Group 30, 19/20 patients in group 45, and 16/20 patients in group 60.

CONCLUSION

We conclude that a wrist extension of 450 appears to be the optimal wrist joint extension for a successful radial artery cannula insertion.

Contamination during 4 years of annual CT screening in the Danish Lung Cancer Screening Trial (DLCST)

INTRODUCTION

Contamination, defined as screening in the control arm, may dilute the statistical power of randomised screening trials. We investigated the rate of contamination in DLCST during 4 years of annual CT screening.

METHODS

DLCST is a randomised trial involving 4104 healthy current and ex smokers. 2052 subjects were randomised to annual low dose chest CT scans (CT group) and 2052 were given no intervention (control group). The study is performed in collaboration with the NELSON trial (Nederlands Leuvens Screening Onderzoek) and mortality data will be pooled at the end. We defined contamination as off study CT scan received for lung cancer screening purposes. Annually during the screening period, the participants were asked whether they had received a CT scan and if so the purpose. The causes were divided into the following categories: 'Off study screening for lung cancer', 'Investigation of lung symptoms', 'Investigation of incidental finding on chest radiograph', 'Participation in other scientific trial involving chest CT', and finally 'Chest CT for other reasons'.

RESULTS

Response rates were high in both groups: 86.1% (control group), 93.6% (CT group) p<0.001.

CONTROL GROUP

199 out of 7065 answers (2.8%) indicating acquisition of a chest CT during 4 years of the trial. Three answers fulfilled the definition of contamination, while 8 received chest CT due to involvement in other scientific trials. 126 reported CT scans as part of investigation for other diseases, while 10 and 52 went through investigations for abnormal chest radiograph and lung symptoms, respectively. CT group: Significantly lower number of answers (n=134) indicated acquisition of an off study chest CT. None had received off study lung cancer screening. Three were involved in other scientific trials, while 17 and 115 went through investigation of lung symptoms and chest CT for other reasons, respectively.

CONCLUSION

Although the frequency of off study chest CT was significantly higher in the control group, it was relatively small in both randomisation groups, and thus contamination seems to be modest and acceptable in the DLCST. Clinical Trial no.: Clinical Trials.gov Protocol Registration System (identification no. NCT00496977).

L-isoleucine-supplemented oral rehydration solution in the treatment of acute diarrhoea in children: a randomized controlled trial

Antimicrobial peptides represent an important component of the innate immune defenses of living organisms, including humans. They are broad-spectrum surface-acting agents secreted by the epithelial cells of the body in response to infection. Recently, L-isoleucine and its analogues have been found to induce antimicrobial peptides. The objectives of the study were to examine if addition of L-isoleucine to oral rehydration salts (ORS) solution would reduce stool output and/or duration of acute diarrhoea in children and induce antimicrobial peptides in intestine. This double-blind randomized controlled trial was conducted at the Dhaka Hospital of ICDDR,B. Fifty male children, aged 6-36 months, with acute diarrhoea and some dehydration, attending the hospital, were included in the study. Twenty-five children received L-isoleucine (2 g/L)-added ORS (study), and 25 received ORS without L-isoleucine (control). Stool weight, ORS intake, and duration of diarrhoea were the primary outcomes. There was a trend in reduction in mean +/- standard deviation (SD) daily stool output (g) of children in the L-isoleucine group from day 2 but it was significant on day 3 (388 +/- 261 vs. 653 +/- 446; the difference between mean [95% confidence interval (CI) (-)265 (-509, -20); p = 0.035]. Although the cumulative stool output from day 1 to day 3 reduced by 26% in the isoleucine group, it was not significant. Also, there was a trend in reduction in the mean +/- SD intake of ORS solution (mL) in the L-isoleucine group but it was significant only on day 1 (410 +/- 169 vs. 564 +/- 301), the difference between mean (95% CI) (-)154 (-288, -18); p = 0.04. The duration (hours) of diarrhoea was similar in both the groups. A gradual increase in stool concentrations of beta-defensin 2 and 3 was noted but they were not significantly different between the groups. L-isoleucine-supplemented ORS might be beneficial in reducing stool output and ORS intake in children with acute watery diarrhoea. A further study is warranted to substantiate the therapeutic effect of L-isoleucine.

Total allograft transplantation of the elbow joint after wide resection of synovial cell sarcoma: a case series

Total elbow allograft transplantation is an option for patients who have extensive joint defects secondary to tumor surgery, trauma, or failed total elbow arthroplasty. This salvage procedure provides patients with a useful, painless range of motion of the elbow. We report our experience with two complete elbow allograft reconstructions after tumor resection surgery with 5 and 6 years of follow-up.