FFRct use for acute chest pain triage in the emergency department: a cost-effectiveness analysis

AIMS

To model and assess the cost-effectiveness of CT-based fractional flow reserve (FFRct) for a population of low to intermediate risk patients for coronary artery disease (CAD) presenting to the emergency department (ED) with acute chest pain.

METHODS AND RESULTS

Using a decision tree model with a 1 year time horizon and from a health care perspective, two diagnostic pathways using FFRct are compared to current clinical routine combining coronary computed tomography angiography (CCTA) with an exercise test. Model data are drawn from the literature and nationally reported data. Outcomes are assessed as the number of avoided invasive coronary angiographies (ICAs) showing no obstructive CAD and quality of life (QoL) in a theoretical cohort of 1000 patients. Sensitivity analyses are performed to test the robustness of the results. Determining FFRct when CCTA is inconclusive is a cost-effective and dominant strategy with a potential saving of 198€/patient, 154 avoided unnecessary ICA showing no obstructive CAD (uICA)/1000 patients and an average improvement in QoL of 0.008 QALY/patient. With an additional 574€/patient, 8 avoided uICA/1000 patients and an improvement in QoL of 0.001 QALY/patient, a strategy where FFRct is always performed is cost-effective only when considering high cost-effectiveness thresholds.

CONCLUSIONS

For patients presenting to the ED with acute chest pain and a low to intermediate pre-test probability of CAD, a diagnostic strategy where FFRct is determined after an inconclusive CCTA is cost-effective. Clinical trials investigating both sensitivity and specificity of FFRct, as well as QoL associated with the use of this technology in this setting are warranted.

Predicting return to work after traumatic brain injury using machine learning and administrative data

BACKGROUND

Accurate patient-specific predictions on return-to-work after traumatic brain injury (TBI) can support both clinical practice and policymaking. The use of machine learning on large administrative data provides interesting opportunities to create such prognostic models.

AIM

The current study assesses whether return-to-work one year after TBI can be predicted accurately from administrative data. Additionally, this study explores how model performance and feature importance change depending on whether a distinction is made between mild and moderate-to-severe TBI.

METHODS

This study used a population-based dataset that combined discharge, claims and social security data of patients hospitalized with a TBI in Belgium during the year 2016. The prediction of TBI was attempted with three algorithms, elastic net logistic regression, random forest and gradient boosting and compared in their performance by their accuracy, sensitivity, specificity and area under the receiver operator curve (ROC AUC).

RESULTS

The distinct modelling algorithms resulted in similar results, with 83% accuracy (ROC AUC 85%) for a binary classification of employed vs. not employed and up to 76% (ROC AUC 82%) for a multiclass operationalization of employment outcome. Modelling mild and moderate-to-severe TBI separately did not result in considerable differences in model performance and feature importance. The features of main importance for return-to-work prediction were related to pre-injury employment.

DISCUSSION

While clearly offering some information beneficial for predicting return-to-work, administrative data needs to be supplemented with additional information to allow further improvement of patient-specific prognose.

Financial implications of the renewed reimbursement system of total hip arthroplasty in Belgium

In Belgium, from June 1st 2018 on, a renewed reim- bursement for hip arthroplasty implants was launched and from January 1st 2019 on, a lump sum covering doctors' fees for "low variable patients", was introduced. We investigated the impact of both reimbursement systems on the funding of a University Hospital in Belgium. All patients from the UZ Brussel with a severity of illness score of one or two whom had an elective total hip replacement implanted between January 1st and May 31st 2018, were included retrospectively. We compared their invoicing data to those of patients operated in the same period but one year later. Moreover, we simulated the invoicing data of both groups as if they had been operated in the other period. Overall, we compared invoicing data of 41 patients before and 30 after the introduction of both renewed reimbursement systems. After the introduction of both new laws, we noted a loss of funding per patient and per intervention between 46.8€ and 753.5€ for a single room and, between 105.5€ and 1877.7€ for a double room. We noted the highest loss in the subcategory "physicians' fees". The renewed reimbursement system is not "budget neutral". In time, the new system can lead to an optimization of care, but it can also lead to a progressive decrease of funding if future fees and implant reimbursements would be aligned towards the national mean. More- over, we fear the new financing system could affect the quality of care and/or result in the selection of profitable patients.

Traumatic brain injury hospitalizations in Belgium: A brief overview of incidence, population characteristics, and outcomes

Background

There is a need for complete and accurate epidemiological studies for traumatic brain injury (TBI). Secondary use of administrative data can provide country-specific population data across the full spectrum of disease.

Aim

This study aims to provide a population-based overview of Belgian TBI hospital admissions as well as their health-related and employment outcomes.

Methods

A combined administrative dataset with deterministic linkage at individual level was used to assess all TBI hospitalizations in Belgium during the year 2016. Discharge data were used for patient selection and description of injuries. Claims data represented the health services used by the patient and health-related follow-up beyond hospitalization. Finally, social security data gave insight in changes to employment situation.

Results

A total of 17,086 patients with TBI were identified, with falls as the predominant cause of injury. Diffuse intracranial injury was the most common type of TBI and 53% had injuries to other body regions as well. In-hospital mortality was 6%. The median length of hospital stay was 2 days, with 20% being admitted to intensive care and 28% undergoing surgery. After hospitalization, 23% had inpatient rehabilitation. Among adults in the labor force pre-injury, 72% of patients with mild TBI and 59% with moderate-to-severe TBI returned to work within 1 year post-injury.

Discussion

Administrative data are a valuable resource for population research. Some limitations need to be considered, however, which can in part be overcome by enrichment of administrative datasets with other data sources such as from trauma registries.

Quantifying injury severity for traumatic brain injury with routinely collected health data

BACKGROUND

Routinely collected health data (RCHD) offers many opportunities for traumatic brain injury (TBI) research, in which injury severity is an important factor.

OBJECTIVE

The use of clinical injury severity indices in a context of RCHD is explored, as are alternative measures created for this specific purpose. To identify useful scales for full body injury severity and TBI severity this study focuses on their performance in predicting these currently used indices, while accounting for age and comorbidities.

DATA

This study utilized an extensive population-based RCHD dataset consisting of all patients with TBI admitted to any Belgian hospital in 2016.

METHODS

Full body injury severity is scored based on the (New) Injury Severity Score ((N)ISS) and the ICD-based Injury Severity Score (ICISS). For TBI specifically, the Abbreviated Injury Scale (AIS) Head, Loss of Consciousness and the ICD-based Injury Severity Score for TBI injuries (ICISS) were used in the analysis. These scales were used to predict three outcome variables strongly related to injury severity: in-hospital death, admission to intensive care and length of hospital stay. For the prediction logistic regressions of the different injury severity scales and TBI severity indices were used, and error rates and the area under the receiver operating curve were evaluated visually.

RESULTS

In general, the ICISS had the best predictive performance (error rate between 0.06 and 0.23; AUC between 0.82 [0.81;0.83] and 0.86 [0.85;0.86]). A clearly increasing error rate can be noticed with advancing age and accumulating comorbidity.

CONCLUSION

Both for full body injury severity and TBI severity, the ICISS tends to outperform other scales. It is therefore the preferred scale for use in research on TBI in the context of RCHD. In their current form, the severity scales are not suitable for use in older populations.

Introduction of the orthogeriatric co-management model increases the quality of care : a pilot study

Traditionally, geriatric patients with musculoskeletal or osteoarticular problems will be admitted to an orthopedic ward and will be treated by sur- geons. However, these patients often suffer from comorbidities requiring geriatric management. In this study, the orthogeriatric co-management (OG- CM) model is compared to traditional orthopedic care model in a retrospective pilot study. In this study, two patients groups were compared during two similar time periods : (1) Group 1 consisted of 119 geriatric patients admitted to an orthopedic (trauma) ward who were treated, with conventional geriatric care on demand (before OG- CM ; October 1-December 31, 2013) and (2) Group 2 consisted of 132 geriatric patients who were admitted after the implementation of the OG-CM model (after OG-CM ; October 1-December 31, 2014). Outcomes measured were : quality of care outcome, mortality and costs. After the introduction of OG-CM, the number of diagnoses increased (P = 0.011) adjusting for sex, age, length of stay (LOS), urgency and getting surgery (yes/ no). However, this did not lead to a significant higher severity of illness (SOI). The number of readmissions within a year were significantly lower after OG-CM (0.31 per patient) compared to before OG-CM (0.89 per patient) (P < 0.001). No significant difference in in-house and reported mortality after 3 months was observed. Costs increased, but no significant differences were found. The OG-CM model demonstrated an increase in quality of care. This was indicated by an increased number of medical diagnoses resulting in having less readmissions, without affecting the mortality rates and the LOS. Future randomized multi-centered studies are required to enable causal relationships.

Health care utilization after hospitalization following a road traffic accident

Purpose: In recent years, there has been an increasing interest in measuring and modeling health care utilization. However, only limited research has been performed in the field of health care utilization following road traffic accidents. This article aims to measure the incremental health care utilization after hospital discharge after a road traffic accident and explore the association between socio-demographic and injury-related variables and health care utilization.Material and methods: Generalized linear models with negative binomial distribution and log-link were executed per type of health care provider (general practitioner, medical specialists, rehabilitation services and outpatient nursing care) and per type of discharge location (discharged to home, discharged to in-hospital rehabilitation). Health care utilization of the 6 months after discharge was compared with the 6 months before the accident (baseline care).Results: Health care utilization six months after discharge is significantly higher than baseline care, except for outpatient nursing care and general practitioners in in-hospital rehabilitation. The increase in visits to medical specialists ranged on average between 1 and 2.2 visits. For general practitioner, there was an increase of 0.4 visits and 0.8 in outpatient nursing care for those who returned home after acute hospitalization. The average increase in rehabilitation services ranged between 3.6 and 20. Associated influential factors differ per health care provider and discharge destination.Conclusion: Evidence of this study suggests higher health care utilization during the first 6 months following hospitalization due to a road traffic injury, compared with baseline care. Associated variables differ per type of health care provider and discharge-destination. More in-depth research on subgroups is needed.Implications for rehabilitationHealth care utilization varies across different patient characteristics and type of injuries which should be considered in the communication with patients on their care trajectory post-discharge.General descriptions of health care utilization in traffic victims at the population level are lacking. Output similar to our study could serve as a reference for post-discharge care planning.The research output can be a starting point for future research on quality indicators of the expected quantity of care.Efforts must be made to estimate suchlike reference tables on post-discharge services in other patient groups and secondary data are a suitable data-source for those analyses.

Variations in hospital costs after traffic injuries: The importance of sociodemographic aspects and comorbidities

OBJECTIVE

The impact of sociodemographic aspects and comorbidities on the inpatient hospital care costs of traffic victims are not clear. The main goal of this study is to provide insights into the sociodemographic characteristics and clinical conditions (including comorbidities) of the victims that result in higher hospital costs.

PARTICIPANTS

For the period 2009-2011, people admitted to a hospital as a result of a road traffic crash (N=64,304) were identified in the national Minimal Hospital Dataset, after which they were linked to their respective claims data from the sickness funds.

METHODS

A generalized linear model was used to analyse hospital costs controlling for roadway user categories, demographics (gender, age, individual socioeconomic status (SES)), and clinical factors (the nature, location, and severity of injury, and comorbidities).

RESULTS

The median hospital cost was € 2801 (IQR € 1510-€ 7175, 2015 Euros). There was no significant difference between gender. Low SES inpatients incurred 16% (95% CI: 14%-18%) higher hospital costs than inpatients of high SES. The presence of comorbidities was associated with an increased hospital cost, however with varying magnitude. For example traffic victims suffering from dementia incur significantly higher hospital costs than those who were not (49% higher, 95% CI: 44%-53%), whereas diabetes was associated with a smaller increase in costs compared to non-diabetics (13%, 95% CI: 10%-16%).

CONCLUSION

Comorbidities and low SES are associated with higher hospital costs for traffic victims, notwithstanding their age, and the nature and the severity of their injury. The broad variability of hospital costs among trauma inpatients should be accounted for when reconsidering financing models. Furthermore, the strong predictive value of some comorbidities and SES on hospital costs should be considered when projections of future health care utilisation in traffic safety scenarios are prepared.

LC-MS/MS analysis of fentanyl and norfentanyl in a fatality due to application of multiple Durogesic transdermal therapeutic systems

Fentanyl is a potent synthetic narcotic analgesic administered in the form of a transdermal patch for the management of chronic pain. A 78-year-old woman with a history of cancer was found dead in bed. She was lying on her back. The external examination revealed 10 Durogesic transdermal therapeutic systems (100 microg/h fentanyl) on the body. Liquid-liquid extraction and liquid chromatography tandem mass spectrometry with electrospray source in positive ionization mode was applied for the quantitation of fentanyl and its major metabolite norfentanyl in the post-mortem samples. Fentanyl-d5 and norfentanyl-d5 were used as internal standards. Multiple reaction monitoring was used for specific detection. Calibration was performed by addition of standard solutions to drug-free matrix (blood, urine and liver) prior to extraction. The method showed good linearity for fentanyl and norfentanyl over a concentration range of 5-150 microg/L in reconstituted extracts with coefficients of determination equal or greater than 0.998. Percent mean within-day precision and accuracy of 0.9-1.0% and 99.4-101.1% for fentanyl and 2.0-4.5% and 93.1-101.0% for norfentanyl were obtained. Mean extraction recoveries varied between 95.5% and 100.3% for fentanyl and 39.2-57.4% for norfentanyl. The following fentanyl (norfentanyl) concentration in the post-mortem samples were measured; 28.6 microg/L (3.0 microg/L) in right and 28.2 microg/L (3.5 microg/L) in left subclavian blood, 21.3 microg/L (<2 microg/L) in right and 20.9 microg/L (<2 microg/L) in left femoral blood, 37.6 microg/L (4.2 microg/L) in right and 33.9 microg/L (4.4 microg/L) in left ventricular blood, 282.9 microg/L (121.2 microg/L) in urine, 688.2 microg/L in stomach contents, 122.5 microg/L (25.4 microg/L) in bile, 19.5 microg/L (< 2 microg/L) in vitreous humour, 203.0 microg/kg (26.6 microg/kg) in liver and 78.6 microg/kg (46.3 microg/kg) in kidney. We concluded that the woman's death was caused by acute intoxication with fentanyl. The manner of death was presumed to be suicide due to excessive administered Durogesic transdermal therapeutic systems.

Toxicological data and growth characteristics of single post-feeding larvae and puparia of Calliphora vicina (Diptera: Calliphoridae) obtained from a controlled nordiazepam study

Larvae of the Calliphora vicina (Diptera: Calliphoridae) were reared on artificial food spiked with different concentrations of nordiazepam. The dynamics of the accumulation and conversion of nordiazepam to its metabolite oxazepam in post-feeding larvae and empty puparia were studied. Analysis was performed using a previously developed liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. This method enabled the detection and quantitation of nordiazepam and oxazepam in single larvae and puparia. Both drugs could be detected in post-feeding larvae and empty puparia. In addition, the influence of nordiazepam on the development and growth of post-feeding larvae was studied. However, no major differences were observed for these parameters between the larvae fed on food containing nordiazepam and the control group. To our knowledge, this is the first report describing the presence of nordiazepam and its metabolite, oxazepam, in single Calliphora vicina larvae and puparia.

Development of a Rapid and Sensitive Method for the Quantitation of Benzodiazepines in Calliphora vicina Larvae and Puparia by LC-MS-MS

Liquid chromatography-tandem mass spectrometry (LC-MS-MS) is emerging as the tool of choice for rapid analysis and the detection of biologically active compounds in complex mixtures. We describe the development of a sensitive method for the simultaneous quantitation of 10 benzodiazepines in Calliphora vicina (Diptera: Calliphoridae) larvae and puparia. The use of larvae for toxicological analyses offers some technical advantages over putrefied tissue. Four sample pretreatment methods for isolating the benzodiazepines out of larvae were evaluated. A simple homogenization, followed by acetonitrile precipitation yielded the highest recoveries. Puparia were pulverized and extracted by ultrasonification in methanol. All extracts were subsequently analyzed using reversed-phase LC-MS-MS. Larvae and puparia calibrators containing benzodiazepines at concentrations ranging from 25 to 750 pg/mg and 50 to 500 pg/mg, respectively, were prepared and analyzed. The method was demonstrated to be linear over the ranges investigated. Limits of detection were from 1.88 to 5.13 pg/mg larva and from 6.28 to 19.03 pg/mg puparium. The developed method was applied to the determination of nordiazepam and its metabolite oxazepam in larvae and puparia of the Calliphora vicina fly that had been reared on artificial foodstuff (beef heart) spiked with 1 microg/g nordiazepam. The larvae were harvested at day 5 for analysis of drug content. The method was sufficiently sensitive to allow the detection of nordiazepam and oxazepam in a single larva or puparium.

An inherited metabolic disorder presenting as ethylene glycol intoxication in a young adult

Despite the abundance of reports emerging in the literature on metabolic disorders, some disorders remain undiagnosed or misdiagnosed, not only in clinical pathology but also in forensic pathology. The authors report a patient who had recurrent episodes characterized by nausea, vomiting, and signs of dehydration necessitating admission to the hospital. At each admission, he was found to have lactic acidosis. On the first admission, glycolic acid was detected in his blood and he was diagnosed as having ethylene glycol intoxication. Only at the third admission, 2 years after the first, was the possibility of an underlying metabolic disorder considered. Laboratory investigations showed a deficiency of complex I in the mitochondrial oxidative phosphorylation. Possible medicolegal implications are discussed.