Quantification of pleural effusion from single area measurements on CT

Ultrasound quantification of pleural effusion volume in supine position: comparison of three model formulae

BACKGROUND

To investigate the accuracy of three model formulae for ultrasound quantification of pleural effusion (PE) volume in patients in supine position.

METHODS

A prospective study including 100 patients with thoracentesis and drainage of PE was conducted. Three model formulae (single section model, two section model and multi-section model) were used to calculate the PE volume. The correlation and consistency analyses between calculated volumes derived from three models and actual PE volume were performed.

RESULTS

PE volumes calculated by three models all showed significant linear correlations with actual PE volume in supine position (all p < 0.001). The reliability of multi-section model in predicting PE volume was significantly higher than that of single section model and slightly higher than that of two section model. When compared with actual drainage volume, the intra-class correlation coefficients (ICCs) of single section model, two section model and multi-section model were 0.72, 0.97 and 0.99, respectively. Significant consistency between calculated PE volumes by using two section model and multi-section model existed for full PE volume range (ICC 0.98).

CONCLUSION

Based on the convenience and accuracy of ultrasound quantification of PE volume, two section model is recommended for pleural effusion assessment in routine clinic, though different model formulae can be selected according to clinical needs.

CT-based pleural effusion volume estimation formula demonstrates low accuracy and reproducibility for traumatic hemothorax

PURPOSE

We aimed to evaluate the accuracy and reproducibility of the CT-based volume estimation formula V = d2 * h, where d and h represent the maximum depth and height of the effusion, for acute traumatic hemothorax.

MATERIALS & METHODS

Prospectively identified patients with CT showing acute traumatic hemothorax were considered. Volumes were retrospectively estimated using d2 * h, then manually measured on axial images. Subgroup analysis was performed on borderline-sized hemothorax (200-400 mL). Measurements were repeated by three non-radiologists. Bland-Altman analysis was used to assess agreement between the two methods and agreement between raters for each method.

RESULTS

A total of 46 patients (median age 34; 36 men) with hemothorax volume 23-1622 mL (median 191 mL, IQR 99-324 mL) were evaluated. Limits of agreement between estimates and measured volumes were -718 - +842 mL (± 202 mL). Borderline-sized hemothorax (n = 13) limits of agreement were -300 - +121 mL (± 114 mL). Of all hemothorax, 85 % (n = 39/46) were correctly stratified as over or under 300 mL, and of borderline-sized hemothorax, 54 % (n = 7/13). Inter-rater limits of agreement were -251 - +350, -694 - +1019, and -696 - +957 for the estimation formula, respectively, and -124 - +190, -97 - +111, and -96 - +46 for the measured volume.

DISCUSSION

An estimation formula varies with actual hemothorax volume by hundreds of mL. There is low accuracy in stratifying hemothorax volumes close to 300 mL. Variability between raters was substantially higher with the estimation formula than with manual measurements.

Analysis of Short-Term Clinical Outcomes and Influencing Factors in Patients with Acute Type B Aortic Intramural Hematoma Treated with Optimal Medical Therapy

This study aimed to investigate the short-term predictors of aortic-related adverse events in patients with acute type B aortic intramural hematoma (IMH) initially treated with optimized medical therapy.A total of 157 patients with acute type B IMH were included in this study. These patients were divided into worsening group (n = 45) and stable group (n = 112) based on the incidence of aortic-related adverse events. The clinical data and imaging features of the two groups were compared. Multivariate logistic regression analysis of predictors of aortic-related adverse events in type B IMH was performed. Receiver operating characteristic (ROC) curve was applied to determine the optimal cutoff value for maximum descending aorta diameter (MDAD). Kaplan-Meier survival curve was used to analyze the incidence of aortic-related adverse events.Worsening and stable groups were statistically significant in diuretics, abnormal D-dimer level, observation endpoint systolic blood pressure (SBP), MDAD, aortic atherosclerosis, ulcer-like projection (ULP), and thickness of hematoma (P < 0.05). Multivariate logistic regression showed that abnormal D-dimer level (OR = 12.464, P = 0.025), MDAD (OR = 1.113, P = 0.030), and ULP (OR = 5.849, P = 0.022) were powerful independent risk factors for predicting aortic-related adverse events in type B IMH, and observation endpoint SBP within 100-120 mmHg (OR = 0.225, P = 0.014) was a protective factor for predicting aortic-related adverse events in type B IMH. The cutoff value of MDAD was 35.2 mm.Short-term imaging is recommended for type B IMH patients with abnormal D-dimer level, MDAD > 35.2 mm, and ULP. Blood pressure should also be strictly monitored and controlled during the acute phase of IMH.

Clinical implications of pleural effusion in patients with acute type B aortic dissection

BACKGROUND

Pleural effusion may complicate acute Stanford type B aortic dissection (ABAD).

AIMS

To identify the relationships between the quantity and side of the pleural effusion, biomarkers and outcomes in patients with ABAD.

METHODS

We undertook a retrospective review of 105 patients with ABAD. Their demographics, the data on admission and during hospital stay, the volume of pleural effusion calculated from the area on computed tomography images and clinical outcomes were analysed.

RESULTS

The median estimated peak volume (median 6.7 days after onset) was 129 ml (63-192, range 26-514 ml) on the left and 11 ml (6-43, range 2-300 ml) on the right. On univariate analysis, the volume of bilateral effusions was associated with anaemia, hypoalbuminaemia and inflammatory markers, whereas the volume of left-sided effusions was associated with older age, low diastolic blood pressure and maximum aortic diameter. Multivariate analysis revealed that hypoalbuminaemia was independently associated with bilateral effusion volume ( P<0.001), while maximum aortic diameter was associated with left-sided effusion volume ( P=0.019). A greater volume of bilateral plural effusion was associated with longer intensive care unit stay.

CONCLUSIONS

Larger bilateral pleural effusions in patients with ABAD were associated with hypoalbuminaemia and potentially with anaemia and inflammation, and may increase the length of intensive care unit stay. Left-sided effusion volume appears to be influenced by the nature of the aortic dilatation. Multiple mechanisms may underpin the development of pleural effusion in ABAD, and are likely to influence clinical outcomes.

Adaptive servo-ventilation suppresses elevation of C-reactive protein and sympathetic activity in acute uncomplicated type B aortic dissection

OBJECTIVES

The aim of this prospective, randomized study was to investigate the effects of adaptive servo-ventilation (ASV), based on haemodynamic parameters, sympathetic status and respiratory conditions in patients with acute uncomplicated type B aortic dissection.

METHODS

We enrolled 28 patients with acute uncomplicated type B aortic dissection requiring antihypertensive therapies, who had been admitted within 24 h from onset. Study subjects were randomly assigned either to the ASV group (n = 14) or to the non-ASV group (n = 14).

RESULTS

Antihypertensive therapy at an acute phase led to significant reduction in blood pressure in both groups. Heart rate significantly dropped in the ASV group. In the non-ASV group, noradrenaline (746 ± 343 to 912 ± 402 pg/ml, P = 0.033) and dopamine (30 ± 21 to 42 ± 28 pg/ml, P = 0.015) significantly increased at 1 h after admission. Low frequency/high frequency ratios significantly decreased in the ASV group (2.1 ± 1.6 to 1.7 ± 1.1, P = 0.045). During follow-up at the subacute period, pleural effusion significantly increased in the non-ASV group (649 ± 611 vs 190 ± 292%, P = 0.033). Peak C-reactive protein (CRP) had a significant positive correlation with pleural effusion volume (P = 0.039) and was significantly greater in the non-ASV group (15.5 ± 6.3 vs 8.5 ± 6.1 mg/dl, P= 0.009).

CONCLUSIONS

In acute type B aortic dissection, ASV was considered to have suppressed the development of sympathetic nervous activity, pleural effusion and elevation of peak CRP.

Fluid in the airway of nontraumatic death on postmortem computed tomography: relationship with pleural effusion and postmortem elapsed time

To evaluate radiographic features of endotracheal/endobronchial fluid in the airway (FA) observed on postmortem computed tomography (PMCT). We studied 164 subjects who died at our hospital between April 2009 and September 2012. Fluid in the airway was considered positive when fluid was identified in the lumen of 1 of the 2 main bronchi in continuity with a segmental bronchus. Pleural effusion and atelectasis/consolidation of the lung lower lobes were also evaluated. Fluid in the airway was observed in 60 (71%) of 84 subjects with unilateral or bilateral pleural effusion, and in 44 (55%) of 80 subjects without pleural effusion (P = 0.029). Of the latter, 41 (93%) had atelectasis/consolidation of the lower lung lobes. Among subjects without pleural effusion, average times after death to PMCT of subjects with and without FA were 501 and 314 minutes, respectively (P = 0.01). Time-course analysis showed that cases with FA on PMCT largely correlated with time after death (R = 0.7966). Fluid in the airway is frequently observed on PMCT in subjects with pleural effusion or atelectasis/consolidation of the lung. No FA in subjects without pleural effusion correlated to shorter times after death. In addition, FA frequency on PMCT increased over time after death.