Complications and outcome in patients with aneurysmal subarachnoid haemorrhage: a prospective hospital based cohort study in the Netherlands

OBJECTIVE—The aim of this study was to investigate prospectively in an unselected series of patients with an aneurysmal subarachnoid haemorrhage what at present the complications are, what the outcome is, how many of these patients have "modern treatment"—that is, early obliteration of the aneurysm and treatment with calcium antagonists—what factors cause a delay in surgical or endovascular treatment, and what the estimated effect on outcome will be of improved treatment.
METHODS—A prospective, observational cohort study of all patients with aneurysmal subarachnoid haemorrhage in the hospitals of a specified region in The Netherlands. The condition on admission, diagnostic procedures, and treatments were recorded. If a patient had a clinical deterioration, the change in Glasgow coma score (GCS), the presence of focal neurological signs, the results of additional investigations, and the final diagnosed cause of the deterioration were recorded.
 Clinical outcome was assessed with the Glasgow outcome scale (GOS) at 3 month follow up. In patients with poor outcome at follow up, the cause was diagnosed.
RESULTS—Of the 110 patients, 47 (43%) had a poor outcome. Cerebral ischaemia, 31 patients (28%), was the most often occurring complication. Major causes of poor outcome were the effects of the initial haemorrhage and rebleeding in 34% and 30% of the patients with poor outcome respectively. Of all patients 102 (93%) were treated with calcium antagonists and 45 (41%) patients had early treatment to obliterate the aneurysm. The major causes of delay of treatment were a poor condition on admission or deterioration shortly after admission, in 31% and 23% respectively.
CONCLUSIONS—In two thirds of the patients with poor outcome the causes of poor outcome are the effects of the initial bleeding and rebleeding. Improved treatment of delayed or postoperative ischaemia will have only minor effects on the outcome of patients with subarachnoid haemorrhage.


A MapReduce Framework for Analysing Portfolios of Catastrophic Risk with Secondary Uncertainty

AbstractThe design and implementation of an extensible framework for performing exploratory analysis of complex property portfolios of catastrophe insurance treaties on the Map-Reduce model is presented in this paper. The framework implements Aggregate Risk Analysis, a Monte Carlo simulation technique, which is at the heart of the analytical pipeline of the modern quantitative insurance/reinsurance pipeline. A key feature of the framework is the support for layering advanced types of analysis, such as portfolio or program level aggregate risk analysis with secondary uncertainty (i.e. computing Probable Maximum Loss (PML) based on a distribution rather than mean values). Such in-depth analysis is not supported by production-based risk management systems since they are constrained by hard response time requirements placed on them. On the other hand, this paper reports preliminary experimental results to demonstrate that in-depth aggregate risk analysis can be realized using a framework based on the MapReduce model

The reliability and reproducibility of the Hertel classification for comminuted proximal humeral fractures compared with the Neer classification

_Introduction_ The Neer classification is the most commonly used fracture classification system for proximal humeral fractures. Inter- and intra-observer agreement is limited, especially for comminuted fractures. A possibly more straightforward and reliable classification system is the Hertel classification. The aim of this study was to compare the inter- and intra-observer variability of the Hertel with the Neer classification in comminuted proximal humeral fractures. _Materials and methods_ Four observers evaluated blinded radiographic images of 60 patients. After at least two months classification was repeated. _Results_ Inter-observer agreement on plain X-rays was fair for both Hertel and Neer. Inter-observer agreement on CT-scans was substantial for Hertel and moderate for Neer. Inter-observer agreement on 3D-reconstructions was moderate for both Hertel and Neer. Intra-observer agreement on plain X-rays was fair for both Hertel and Neer. Intra-observer agreement on CT-scans was moderate for both Hertel and Neer. Intra-observer agreement on 3D-reconstructions was moderate for Hertel and substantial for Neer. _Conclusions_ The Hertel and Neer classifications showed a fair to substantial inter- and intra-observer agreement on the three diagnostic modalities used. Although inter-observer agreement was highest for Hertel classification on CT-scans, Neer classification had the highest intra-observer agreement on 3D-reconstructions. Data of this study do not confirm superiority of either classification system for the classification of comminuted proximal humeral fractures

Refining the criteria for immediate total-body CT after severe trauma

Objectives: Initial trauma care could potentially be improved when conventional imaging and selective CT scanning is omitted and replaced by immediate total-body CT (iTBCT) scanning. Because of the potentially increased radiation exposure by this diagnostic approach, proper selection of the severely injured patients is mandatory. Methods: In the REACT-2 trial, severe trauma patients were randomized to iTBCT or conventional imaging and selective CT based on predefined criteria regarding compromised vital parameters, clinical suspicion of severe injuries, or high-risk trauma mechanisms in five trauma centers. By logistic regression analysis with backward selection on the 15 study inclusion criteria, a revised set of criteria was derived and subsequently tested for prediction of severe injury and shifts in radiation exposure. Results: In total, 1083 patients were enrolled with median ISS of 20 (IQR 9–29) and median GCS of 13 (IQR 3–15). Backward logistic regression resulted in a revised set consisting of nine original and one adjusted criteria. Positive predictive value improved from 76% (95% CI 74–79%) to 82% (95% CI 80–85%). Sensitivity decreased by 9% (95% CI 7–11%). The area under the receiver operating characteristics curve remained equal and was 0.80 (95% CI 0.77–0.83), original set 0.80 (95% CI 0.77–0.83). The revised set retains 8.78 mSv (95% CI 6.01–11.56) for 36% of the non-severely injured patients. Conclusions: Selection criteria for iTBCT can be reduced from 15 to 10 clinically criteria. This improves the positive predictive value for severe injury and reduces radiation exposure for less severely injured patients. Key Points: • Selection criteria for iTBCT can be reduced to 10 clinically useful criteria. • This reduces radiation exposure in 36% of less severely injured patients. • Overall discriminative capacity for selection of severely injured patients remained equal

Identification of chronic thromboembolic pulmonary hypertension on CTPAs performed for diagnosing acute pulmonary embolism depending on level of expertise

Background: Expert reading often reveals radiological signs of chronic thromboembolic pulmonary hypertension (CTEPH) or chronic PE on computed tomography pulmonary angiography (CTPA) performed at the time of acute pulmonary embolism (PE) presentation preceding CTEPH. Little is known about the accuracy and reproducibility of CTPA reading by radiologists in training in this setting. Objectives: To evaluate 1) whether signs of CTEPH or chronic PE are routinely reported on CTPA for suspected PE; and 2) whether CTEPH-non-expert readers achieve comparable predictive accuracy to CTEPH-expert radiologists after dedicated instruction. Methods: Original reports of CTPAs demonstrating acute PE in 50 patients whom ultimately developed CTEPH, and those of 50 PE who did not, were screened for documented signs of CTEPH. All scans were re-assessed by three CTEPH-expert readers and two CTEPH-non-expert readers (blinded and independently) for predefined signs and overall presence of CTEPH. Results: Signs of chronic PE were mentioned in the original reports of 14/50 cases (28%), while CTEPH-expert radiologists had recognized 44/50 (88%). Using a standardized definition (>= 3 predefined radiological signs), moderate-to-good agreement was reached between CTEPH-non-expert readers and the experts' consensus (kstatistics 0.46; 0.61) at slightly lower sensitivities. The CTEPH-non-expert readers had moderate agreement on the presence of CTEPH (Kappa-statistic 0.38), but both correctly identified most cases (80% and 88%, respectively). Conclusions: Concomitant signs of CTEPH were poorly documented in daily practice, while most CTEPH patients were identified by CTEPH-non-expert readers after dedicated instruction. These findings underline the feasibility of achieving earlier CTEPH diagnosis by assessing CTPAs more attentively.Cardiovascular Aspects of Radiolog

Follow-up infarct volume as a mediator of endovascular treatment effect on functional outcome in ischaemic stroke

Objective: The putative mechanism for the favourable effect of endovascular treatment (EVT) on functional outcome after acute ischaemic stroke is preventing follow-up infarct volume (FIV) progression. We aimed to assess to what extent difference in FIV explains the effect of EVT on functional outcome in a randomised trial of EVT versus no EVT (MR CLEAN). Methods: FIV was assessed on non-contrast CT scan 5–7 days after stroke. Functional outcome was the score on the modified Rankin Scale at 3 months. We tested the causal pathway from intervention, via FIV to functional outcome with a mediation model, using linear and ordinal regression, adjusted for relevant baseline covariates, including stroke severity. Explained effect was assessed by taking the ratio of the log odds ratios of treatment with and without adjustment for FIV. Results: Of the 500 patients included in MR CLEAN, 60 died and four patients underwent hemicraniectomy before FIV was assessed, leaving 436 patients for analysis. Patients in the intervention group had better functional outcomes (adjusted common odds ratio (acOR) 2.30 (95% CI 1.62–3.26) than controls and smaller FIV (median 53 vs. 81 ml) (difference 28 ml; 95% CI 13–41). Smaller FIV was associated with better outcome (acOR per 10 ml 0.60, 95% CI 0.52–0.68). After adjustment for FIV the effect of intervention on functional outcome decreased but remained substantial (acOR 2.05, 95% CI 1.44–2.91). This implies that preventing FIV progression explains 14% (95% CI 0–34) of the beneficial effect of EVT on outcome. Conclusion: The effect of EVT on FIV explains only part of the treatment effect on functional outcome. Key Points: • Endovascular treatment in acute ischaemic stroke patients prevents progression of follow-up infarct volume on non-contrast CT at 5–7 days.• Follow-up infarct volume was related to functional outcome, but only explained a modest part of the effect of intervention on functional outcome.• A large proportion of treatment effect on functional outcome remains unexplained, suggesting FIV alone cannot be used as an early surrogate imaging marker of functional outcome

Prediction of chronic thromboembolic pulmonary hypertension with standardised evaluation of initial computed tomography pulmonary angiography performed for suspected acute pulmonary embolism

Objectives Closer reading of computed tomography pulmonary angiography (CTPA) scans of patients presenting with acute pulmonary embolism (PE) may identify those at high risk of developing chronic thromboembolic pulmonary hypertension (CTEPH). We aimed to validate the predictive value of six radiological predictors that were previously proposed. Methods Three hundred forty-one patients with acute PE were prospectively followed for development of CTEPH in six European hospitals. Index CTPAs were analysed post hoc by expert chest radiologists blinded to the final diagnosis. The accuracy of the predictors using a predefined threshold for 'high risk' (>= 3 predictors) and the expert overall judgment on the presence of CTEPH were assessed. Results CTEPH was confirmed in nine patients (2.6%) during 2-year follow-up. Any sign of chronic thrombi was already present in 74/341 patients (22%) on the index CTPA, which was associated with CTEPH (OR 7.8, 95%CI 1.9-32); 37 patients (11%) had >= 3 of 6 radiological predictors, of whom 4 (11%) were diagnosed with CTEPH (sensitivity 44%, 95%CI 14-79; specificity 90%, 95%CI 86-93). Expert judgment raised suspicion of CTEPH in 27 patients, which was confirmed in 8 (30%; sensitivity 89%, 95%CI 52-100; specificity 94%, 95%CI 91-97). Conclusions The presence of >= 3 of 6 predefined radiological predictors was highly specific for a future CTEPH diagnosis, comparable to overall expert judgment, while the latter was associated with higher sensitivity. Dedicated CTPA reading for signs of CTEPH may therefore help in early detection of CTEPH after PE, although in our cohort this strategy would not have detected all cases.Cardiovascular Aspects of Radiolog