Predicting Shunt Dependency from the Effect of Cerebrospinal Fluid Drainage on Ventricular Size

BACKGROUND

Prolonged external ventricular drainage (EVD) in patients with subarachnoid hemorrhage (SAH) leads to morbidity, whereas early removal can have untoward effects related to recurrent hydrocephalus. A metric to help determine the optimal time for EVD removal or ventriculoperitoneal shunt (VPS) placement would be beneficial in preventing the prolonged, unnecessary use of EVD. This study aimed to identify whether dynamics of cerebrospinal fluid (CSF) biometrics can temporally predict VPS dependency after SAH.

METHODS

This was a retrospective analysis of a prospective, single-center, observational study of patients with aneurysmal SAH who required EVD placement for hydrocephalus. Patients were divided into VPS-dependent (VPS+) and non-VPS dependent groups. We measured the bicaudate index (BCI) on all available computed tomography scans and calculated the change over time (ΔBCI). We analyzed the relationship of ΔBCI with CSF output by using Pearson's correlation. A k-nearest neighbor model of the relationship between ΔBCI and CSF output was computed to classify VPS.

RESULTS

Fifty-eight patients met inclusion criteria. CSF output was significantly higher in the VPS+ group in the 7 days post EVD placement. There was a negative correlation between delta BCI and CSF output in the VPS+ group (negative delta BCI means ventricles become smaller) and a positive correlation in the VPS- group starting from days four to six after EVD placement (p < 0.05). A weighted k-nearest neighbor model for classification had a sensitivity of 0.75, a specificity of 0.70, and an area under the receiver operating characteristic curve of 0.80.

CONCLUSIONS

The correlation of ΔBCI and CSF output is a reliable intraindividual biometric for VPS dependency after SAH as early as days four to six after EVD placement. Our machine learning model leverages this relationship between ΔBCI and cumulative CSF output to predict VPS dependency. Early knowledge of VPS dependency could be studied to reduce EVD duration in many centers (intensive care unit length of stay).

Hypercoagulable viscoelastic blood clot characteristics in critically ill coronavirus disease 2019 patients and associations with thrombotic complications

BACKGROUND

Critically ill coronavirus disease 2019 (COVID-19) patients have frequent thrombotic complications and laboratory evidence of hypercoagulability. The relationship of coagulation tests and thrombosis requires investigation to identify best diagnostic and treatment approaches. We assessed for hypercoagulable characteristics in critically ill COVID-19 patients using rotational thromboelastometry (ROTEM) and explored relationships of D-dimer and ROTEM measurements with thrombotic complications.

METHODS

Critically ill adult COVID-19 patients receiving ROTEM testing between March and April 2020 were analyzed. Patients receiving therapeutic anticoagulation before ROTEM were excluded. Rotational thromboelastometry measurements from COVID-19 patients were compared with non-COVID-19 patients matched by age, sex, and body mass index. Intergroup differences in ROTEM measurements were assessed using t tests. Correlations of D-dimer levels to ROTEM measurements were assessed in COVID-19 patients who had available concurrent testing. Intergroup differences of D-dimer and ROTEM measurements were explored in COVID-19 patients with and without thrombosis.

RESULTS

Of 30 COVID-19 patients receiving ROTEM, we identified hypercoagulability from elevated fibrinogen compared with non-COVID-19 patients (fibrinogen assay maximum clot firmness [MCF], 47 ± 13 mm vs. 20 ± 7 mm; mean intergroup difference, 27.4 mm; 95% confidence interval [CI], 22.1-32.7 mm; p < 0.0001). In our COVID-19 cohort, thrombotic complications were identified in 33%. In COVID-19 patients developing thrombotic complications, we identified higher D-dimer levels (17.5 ± 4.3 μg/mL vs. 8.0 ± 6.3 μg/mL; mean difference, 9.5 μg/mL; 95% CI, 13.9-5.1; p < 0.0001) but lower fibrinogen assay MCF (39.7 ± 10.8 mm vs. 50.1 ± 12.0 mm; mean difference, -11.2 mm; 95% CI, -2.1 to -20.2; p = 0.02) compared with patients without thrombosis. We identified negative correlations of D-dimer levels and ROTEM MCF in these patients (r = -0.61; p = 0.001).

CONCLUSION

We identified elevated D-dimer levels and hypercoagulable blood clot characteristics from increased fibrinogen on ROTEM testing in critically ill COVID-19 patients. However, we identified lower, albeit still hypercoagulable, ROTEM measurements of fibrinogen in COVID-19 patients with thrombotic complications compared with those without. Further work is required to externally validate these findings and to investigate the mechanistic drivers for these relationships to identify best diagnostic and treatment approaches for these patients.

LEVEL OF EVIDENCE

Epidemiologic, level IV.

[Treatment manual for psychotherapy of acute and posttraumatic stress disorders after multiple ICD shocks]

In view of the inceasing number of implanted defibrillators in all industrial nations, the number of people who have suffered so-called multiple shocks (electrical storm, ES) also increases. Common complaints are severe and continuously recurrent massive anxiety, panic attacks, fear of death, helplessness and hopelessness, depression, nervosity and irritability as well as reclusive and uncontrollable avoidance behaviour, intrusions, nightmares, flashbacks, sleeplessness and the inability to show feelings and limitation of future perspectives. Because people with an ICD are often physically (very) ill and after multiple ICD shocks are additionally very insecure, it would seem logical if the inpatient treatment would be carried out in an institution which has close connections and is also spatially close to a cardiology department. The basis of the diagnostics is the clinical anamnesis and a systematic exploration of the trauma situation and the resulting complaints. As an additional diagnostic element psychological test procedures should be implemented to determine the core symptomatic (anxiety, depression, trauma symptoms). Psychological test procedures should be included in the diagnostics so that at the end of treatment it is obvious even to the patient which alterations have occurred. The core element of inpatient treatment is daily intensive psychotherapy and includes deep psychologically well-founded psychotherapy and behavioral therapeutic-oriented anxiety therapy as well as cognitive restructuring and elements of eye movement desensitization and reprocessing (EMDR). A follow-up examination within 4 months of the multiple shocks episode is recommended because symptoms of posttraumatic stress disorder often occur after a long latent time period.

Prevalence of patent foramen ovale (PFO) and MRI-lesions in mild neurological decompression sickness (type B-DCS/AGE)

BACKGROUND

Neurological decompression sickness (DCS/AGE) may cover two variants with either severer and probably central nervous (Type A) or milder and sometimes doubtful neurological symptoms (Type B). The pathophysiology of the Type B-DCS/AGE might be different from the Type A-variant. In Type A-DCS/AGE a higher PFO-prevalence (patent foramen ovale) points towards an embolic origin of the Type A-symptomatology. This is not necessarily expected for the Type B-DCS/AGE if the pathophysiology here is micro-embolic or even non-embolic.

METHODS

18 patients with Type B-DCS/AGE were tested against matched controls for presence and size of a PFO with echocardiography and transcranial ultrasound with echo-contrast. Prevalence and number of Type A-brain lesions were visualized by cranial MRI as possible sequelae from gas-embolic events.

RESULTS

PFO-prevalence in both groups, the patients with Type B-DCS/AGE (5/18) as well as the controls (7/18) was similar to published PFO-prevalences in normals without any difference between patients and controls (p = 0.725). Also the number of MRI-lesions (ACFs) was the same for Type B-DCS/AGE cases (15 ACFs in 5 patients) and controls (37 ACFs in 8 divers).

CONCLUSION

Indirect findings suggesting embolic brain injuries are found with similar frequency in patients with Type B-DCS/AGE and normal controls, which is in contrast to data about Type A-DCS/AGE. This is compatible with different pathophysiological mechanisms involved in the Type A- and Type B-DCS/AGE.

Resolving abbreviations to their senses in Medline

MOTIVATION

Biological literature contains many abbreviations with one particular sense in each document. However, most abbreviations do not have a unique sense across the literature. Furthermore, many documents do not contain the long forms of the abbreviations. Resolving an abbreviation in a document consists of retrieving its sense in use. Abbreviation resolution improves accuracy of document retrieval engines and of information extraction systems.

RESULTS

We combine an automatic analysis of Medline abstracts and linguistic methods to build a dictionary of abbreviation/sense pairs. The dictionary is used for the resolution of abbreviations occurring with their long forms. Ambiguous global abbreviations are resolved using support vector machines that have been trained on the context of each instance of the abbreviation/sense pairs, previously extracted for the dictionary set-up. The system disambiguates abbreviations with a precision of 98.9% for a recall of 98.2% (98.5% accuracy). This performance is superior in comparison with previously reported research work.

AVAILABILITY

The abbreviation resolution module is available at http://www.ebi.ac.uk/Rebholz/software.html.

Humanbiomonitoring-Untersuchungen von Organohalogenverbindungen - PCB, DDE; HCB, β- und γ-HCH, PCDD/PCDF, koplanaren PCB sowie polybromierten Biphenylethern

Although PCB and PCB-containing materials are not processed for a long time, PCB is under discussion again and again caused by the pollution of indoor environments. To objectify the discussion, the dates of the PCB-biomonitoring, the organochlorine-compounds (DDE, HCB, beta-/gamma -HCH, PCDD/PCDF) and the polybrominated biphenyl ethers concerning the investigations within the project "Sentinel Health Departments" in Baden-Wurttemberg are represented. Additionally results from children from Kazakhstan (Aral-Sea area) and from teachers which are working in PCB polluted schools as well as from a long term investigated test person are reported. Blood concentrations of the following compounds decreased from 1996/97 to 2002/03: the sum of the concentration of PCB 138,153 and 180 decreased from 0.46 microg/L to 0.20 microg/L, DDE from 0.32 microg/L to 0.17 microg/, HCB from 0.20 microg/L to 0.08 microg/L, beta-HCH below the level of detection, I-TEQ NATO to 4.8 pg/g blood fat, TEQ WHO (without PCB) to 5.5 pg/g blood fat, PCB 126 to 18,8,pg/g blood fat and PCB 169 to 12.8 pg/g blood fat. The influence of breast feeding and the gender on the level of the pollution is conspicious. No local correlations were found in Baden-Wurttemberg, but they were found in comparison with the results of Kazakhstan (Aral-Sea area). The difficulty to produce time series while the analyzing pollutants are more and more decreasing, as well as the change of the calculation base of the summation of parameters like I-TEQ NATO to TEQ WHO are discussed.

Localization of interictal spikes using SAM(g2) and dipole fit

SAM(g2) is an automated analysis that transforms the MEG data into a functional image of spike-like activity, giving the source waveforms for those locations. Since the source waveforms estimated by SAM have higher signal-to-noise ratio (SNR) than does the raw MEG data, it is possible to automatically mark the location and timing of each spike for comparisons with dipole fit procedures. Both SAM(g2) and equivalent current dipole (ECD) fits were used to analyze MEG interictal spike recordings in 10 patients with cortical dysplasias and medial temporal lobe epilepsy. The ECD fit locations obtained by manual spike classification and latency marking were compared with those found by automated SAM(g2) procedures. When the SNR of interictal activity was high (compared to the background) with a clear single focus, there was excellent agreement between the ECD cluster location and the SAM(g2) maximum. However, when the SNR of spikes was low, manual single ECD location scatter was larger than SAM(g2) reconstructions. When multiple independent interictal spike loci were present, there was some disagreement between SAM(g2) and ECD scatter in the cases of low SNR spikes. When SAM(g2) indicated multiple coupled spike loci, the residual variance for the dipole fit was high and its scatter unacceptably large--even for multiple dipole models. This study demonstrates that SAM(g2) is equivalent to ECD fit for localizing interictal spikes when there is a single locus and good SNR. Further studies are required to validate cases in which there are multiple spike loci or poor SNR.

[Determination of mold concentrations in homes and schools in Baden-Württemberg]

So far there have been rather few reliable and comparable data available on indoor pollution with mould. Following the publication of the Federal Environmental Agency and the Health Agency Baden-Württemberg which supports the assessment of mould pollution of indoor air, it seemed advisable to investigate as to how far these criteria can be used for the assessing the mould pollution in daily practice. The results of investigations of 130 homes and 117 classrooms in Baden-Württemberg. will be represented.

[10 years of observation by public health offices in Baden-Württemberg--assessment of human biomonitoring for mercury due to dental amalgam fillings and other sources]

Since 1992, in Baden-Württemberg, ten-year old children have been surveyed in the project "Sentinel Health Departments" to study their exposure to environmental pollutants and possible health effects. In the four study areas 1200 children have been investigated every year initially, since 1996 every second year. The data for mercury in body fluids are reported here. The decrease in the body burden of mercury as a result of the declining usage of dental amalgam fillings, was been verified. In 1992/93, of all the children who had been surveyed, the 95 percentile for the body burden of mercury was 3.1 microg/l and in 2000/01 1.35 microg/l. Also to be discussed is the reason why mercury-based cosmetic ointments seriously exceed the HBM-II-intervention-value. Because of using these ointments, concentrations of mercury in urine up to 1400 microg/l were found. A study within the project "Sentinel Health Departments" compared the concentrations of mercury in the urine of adults with those in blood and salvia. The results support the opinion that mercury in urine is appropriate for estimating the mercury uptake from dental amalgam fillings. It can be assumed that these results reflect the situation in the entire Federal Republic of Germany. The ten years' experience confirms that the concept of the "Sentinel Health Departments" is excellently suited to obtain data relevant for environmental health of children. Environmental health protection and the essential gathering of data for future health observation in Baden-Württemberg.

[Anxiety: an aspect of the interaction of doctor and patients on the waiting-list and after lung-transplantation]

Anxiety occurs frequently in patients who are on the waiting-list for a lung-transplantation or have already been transplanted. In this context anxiety is a theme of every interaction of doctor and patient but often remains unrecognized because it hides behind bodily symptoms and mechanisms of defense. Anxiety affects patients' behavior and compliance and may afflict - especially if not recognized - doctors' decisions and thus patients' health and survival. It is therefore necessary to recognize and to openly handle anxiety in the interaction of doctor and patient.

HERV-K: the biologically most active human endogenous retrovirus family

The human genome contains a wide variety of endogenous retrovirus-like sequences. The human endogenous retrovirus type K (HERV-K) family comprises 30-50 members per haploid genome in humans and is highly conserved in Old World monkeys and apes. Some proviruses are displaying open reading frames (ORF) with coding capacity for viral particles. HERV-K sequences most likely code for the previously described human teratocarcinoma-derived virus (HTDV) and correlated expression of HERV-K Gag has been demonstrated by immunoelectron microscopy studies. Protease, but not yet reverse transcriptase (RT), enzymatic activity was demonstrated for recombinant HERV-K proteins. However, an ultrasensitive RT assay revealed specific polymerase activity associated with the HTDV particles. HERV-K transcription is specifically regulated by viral long terminal repeats and RNA is expressed at low steady-state levels in a variety of human tissues and tumours. In teratocarcinoma cell lines, HERV-K is highly expressed in a complex pattern showing full-length as well as subgenomic envelope (env) and two alternatively spliced small transcripts. The doubly spliced 1.8-kb mRNA codes for cORF protein which resembles Rev of HIV-1 and is located in the nucleolus. In addition, the cORF sequence acts as a leader and is essential for effective expression of glycosylated HERV-K Env protein. Although HERV-K sequences code for all necessary retroviral proteins, infectious particles could not yet be demonstrated. The putative implication of HERV sequences in pathophysiological processes, for example, testicular malignancies, remains to be elucidated.