Automated and app-based activation of first responders for prehospital cardiac arrest: an analysis of 16.500 activations of the KATRETTER system in Berlin

BACKGROUND

Bystander CPR is one of the main independent factors contributing to better survival after out-of-hospital cardiac arrest. Simultaneously, the rate of bystander CPR in Germany is below the European average. First responder applications (apps) contribute to reducing the time period without CPR (no-flow time) until professional help can arrive on-scene.

METHODS

The KATRETTER app was introduced in Berlin as one of the first apps in Europe which do not require any medical qualifications to register as a first responder. The activation of volunteer first responders for suspected cardiac arrest cases through the Berlin Emergency Medical Services integrated control center was evaluated based on data collected between 16 Oct 2020 and 16 Oct 2022. Our descriptive analysis includes the number of registered first responders, number of activations, the number and percentages of accepted activations, as well as all reports where first responders arrived at the scene.

RESULTS

As of 15 Oct 2022, a total of 10,102 first responders were registered in the state of Berlin. During this specified period, there were 16.505 activations of the system for suspected out-of-hospital cardiac arrest. In 38.4% of the accepted cases, first responders documented patient contact, and in 34.6% of cases with patient contact, CPR was performed. Only 2% of registered first responders did not have any medical qualifications.

CONCLUSIONS

Smartphone-based first responder applications should not be understood as a means of alerting professional help, but rather like a digitally amplified "call for help" in the vicinity of an emergency location. A large number of first responders can be recruited within 24 months, without large-scale public relations work necessary. No qualifications were required to become a first responder, contributing to a low-threshold registration process with the effect of a more widespread distribution of the app and cost reduction during implementation.

[Introduction of emergency paramedic investigators in the context of the COVID-19 pandemic in the Berlin emergency medical service]

BACKGROUND

It has been shown throughout the COVID-19 pandemic that the condition of a number of patients deteriorates acutely when not monitored. This is set against an increased demand for emergency medical services and the resulting scarcity of resources, which makes it necessary to prioritise inpatient treatment or ensure that patients are provided with appropriate outpatient care. In this context, the Berlin Fire Department has introduced emergency paramedic investigators (NotSan-Erkunder) as an additional operating resource.

METHODOLOGY

We assessed all operations from 28.03.2020 to 28.04.2020 during which Emergency Paramedic Investigators of the Berlin emergency services were deployed. A total of 341 operations were included from the 31 days. Alongside data from the dispatch system, all operational documentation was assessed.

RESULTS

In 57% of cases, mNACA II patients (outpatient treatment) were identified, in 42% of cases, mNACA III patients (inpatient treatment) were identified, and in 1% of cases, mNACA IV (imminent danger to life) patients were identified. In 51% of cases, the emergency services transported the patient to a hospital, and in 49%, alternative care measures were employed. These included referral to a local physician in 28% of cases. In 11% of cases, patients were referred to on-call services of the Association of Statutory Health Insurance Physicians (KV in German). In 4% of cases, the Berlin Fire Department emergency dispatch center deployed a physician of the KV (KV-ARE investigator).

DISCUSSION

The results show that additional operational resources serve an important function during a pandemic with regards to an initial assessment and pilot function. This can help relieve not only the emergency services but also the medical facilities responsible for providing further care. The standardised dispatch enquiry enables the linking with the appropriate codes from the low-priority operational spectrum and support by a Tele-emergency physician lends additional professional competency to the emergency paramedics.

BNST and amygdala activation to threat: Effects of temporal predictability and threat mode

Recent animal and human studies highlight the uncertainty about the onset of an aversive event as a crucial factor for the involvement of the centromedial amygdala (CM) and bed nucleus of the stria terminalis (BNST) activity. However, studies investigating temporally predictable or unpredictable threat anticipation and confrontation processes are rare. Furthermore, the few existing fMRI studies analyzing temporally predictable and unpredictable threat processes used small sample sizes or limited fMRI paradigms. Therefore, we measured functional brain activity in 109 predominantly female healthy participants during a temporally predictable-unpredictable threat paradigm, which aimed to solve limited aspects of recent studies. Results showed higher BNST activity compared to the CM during the cue indicating that the upcoming confrontation is aversive relative to the cue indicating an upcoming neutral confrontation. Both the CM and BNST showed higher activity during the confrontation with unpredictable and aversive stimuli, but the reaction to aversive confrontation relative to neutral confrontation was stronger in the CM compared to the BNST. Additional modulation analyses by NPSR1 rs324981 genotype revealed higher BNST activity relative to the CM in unpredictable anticipation relative to predictable anticipation in T-carriers compared to AA carriers. Our results indicate that during the confrontation with aversive or neutral stimuli, temporal unpredictability modulates CM and BNST activity. Further, there is a differential activity concerning threat processing, as BNST is more involved when focussing on fear-related anticipation processes and CM is more involved when focussing on threat confrontation.

Evidence for adult age-invariance in associative false recognition

Older people are more prone to memory distortions and errors than young people, but do not always show greater false recognition in the Deese-Roediger-McDermott (DRM) task. We report two preregistered experiments investigating whether recent findings of age-invariant false recognition extend to designs in which studied items are blocked. According to (Tun, P. A., Wingfield, A., Rosen, M. J., & Blanchard, L. (1998). Response latencies for false memories: Gist-based processes in normal aging. Psychology and Aging, 13(2), 230-241.), age effects on false recognition in the DRM task are due to a greater reliance on gist processing which is enhanced under blocked study conditions. Experiment 1 assessed false recognition in an online variant of the DRM task where words were presented visually, with incidental encoding. The results showed Bayesian evidence against greater false recognition by older adults, whether lures were semantically associated with studied lists, or perceptually related (presented in the same distinctive font as studied lists) or both. Experiment 2 used a typical DRM procedure with auditory lists and intentional encoding, closely reproducing (Tun, P. A., Wingfield, A., Rosen, M. J., & Blanchard, L. (1998). Response latencies for false memories: Gist-based processes in normal aging. Psychology and Aging, 13(2), 230-241.) Experiment 2 but omitting an initial test of recall. The results showed evidence against an age-related increase in critical lure false recognition under these conditions. Together, the data suggest that older people do not make more associative memory errors in recognition tests than young people.

[Mass casualty incidents and attacks involving a multitude of children and adolescents-Overview of policy recommendations and challenges]

Fortunately, mass casualty incidents involving a large number of children and adolescents are rare and the experience in this field, both in terms of medical as well as psychosocial emergency care is comparatively low. Children represent a vulnerable group and have a particularly high risk of developing posttraumatic stress disorder in the aftermath of experiencing disasters. A selective literature search was carried out in Medline. The peculiarity of damaging events with a large number of children and adolescents affected is that in addition to emergency medical care, an early approach to psychosocial emergency care must be provided. Accordingly, it makes sense to integrate such structures into the respective deployment concepts. A specific screening algorithm for children could so far not prevail but due to the physiological and anatomical characteristics appropriate emergency medical care concepts should be provided. Furthermore, hospitals must adapt to this patient group in a suitable manner.

Stomatal CO2 responsiveness and photosynthetic capacity of tropical woody species in relation to taxonomy and functional traits

Stomatal CO2 responsiveness and photosynthetic capacity vary greatly among plant species, but the factors controlling these physiological leaf traits are often poorly understood. To explore if these traits are linked to taxonomic group identity and/or to other plant functional traits, we investigated the short-term stomatal CO2 responses and the maximum rates of photosynthetic carboxylation (V cmax) and electron transport (J max) in an evolutionary broad range of tropical woody plant species. The study included 21 species representing four major seed plant taxa: gymnosperms, monocots, rosids and asterids. We found that stomatal closure responses to increased CO2 were stronger in angiosperms than in gymnosperms, and in monocots compared to dicots. Stomatal CO2 responsiveness was not significantly related to any of the other functional traits investigated, while a parameter describing the relationship between photosynthesis and stomatal conductance in combined leaf gas exchange models (g 1) was related to leaf area-specific plant hydraulic conductance. For photosynthesis, we found that the interspecific variation in V cmax and J max was related to within leaf nitrogen (N) allocation rather than to area-based total leaf N content. Within-leaf N allocation and water use were strongly co-ordinated (r 2 = 0.67), such that species with high fractional N investments into compounds maximizing photosynthetic capacity also had high stomatal conductance. We conclude that while stomatal CO2 responsiveness of tropical woody species seems poorly related to other plant functional traits, photosynthetic capacity is linked to fractional within-leaf N allocation rather than total leaf N content and is closely co-ordinated with leaf water use.

Responses of the Human Brain to Mild Dehydration and Rehydration Explored In Vivo by 1H-MR Imaging and Spectroscopy

BACKGROUND AND PURPOSE

As yet, there are no in vivo data on tissue water changes and associated morphometric changes involved in the osmo-adaptation of normal brains. Our aim was to evaluate osmoadaptive responses of the healthy human brain to osmotic challenges of de- and rehydration by serial measurements of brain volume, tissue fluid, and metabolites.

MATERIALS AND METHODS

Serial T1-weighted and (1)H-MR spectroscopy data were acquired in 15 healthy individuals at normohydration, on 12 hours of dehydration, and during 1 hour of oral rehydration. Osmotic challenges were monitored by serum measures, including osmolality and hematocrit. MR imaging data were analyzed by using FreeSurfer and LCModel.

RESULTS

On dehydration, serum osmolality increased by 0.67% and brain tissue fluid decreased by 1.63%, on average. MR imaging morphometry demonstrated corresponding decreases of cortical thickness and volumes of the whole brain, cortex, white matter, and hypothalamus/thalamus. These changes reversed during rehydration. Continuous fluid ingestion of 1 L of water for 1 hour within the scanner lowered serum osmolality by 0.96% and increased brain tissue fluid by 0.43%, on average. Concomitantly, cortical thickness and volumes of the whole brain, cortex, white matter, and hypothalamus/thalamus increased. Changes in brain tissue fluid were related to volume changes of the whole brain, the white matter, and hypothalamus/thalamus. Only volume changes of the hypothalamus/thalamus significantly correlated with serum osmolality.

CONCLUSIONS

This is the first study simultaneously evaluating changes in brain tissue fluid, metabolites, volume, and cortical thickness. Our results reflect cellular volume regulatory mechanisms at a macroscopic level and emphasize that it is essential to control for hydration levels in studies on brain morphometry and metabolism in order to avoid confounding the findings.

Results of the first interim analysis of the CARMA study to investigate efficacy and safety profile of catumaxomab in clinical practice

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Background: The trifunctional antibody catumaxomab is approved in the EU for intraperitoneal (i.p.) treatment of malignant ascites in patients (pts) with EpCAM-positive carcinomas. Clinical data for catumaxomab are based on the pivotal trial and several phase I/II trials. So far, the routine use of catumaxomab in clinical practice has not been evaluated systematically. Therefore, a large prospective observational study was started in 2010. The study investigates the administration of catumaxomab in a total of 160 pts with malignant ascites under routine conditions in daily clinical practice. Here we show the results of the first pre-planned interim analysis. Methods: The analysis included 49 pts with malignant ascites due to EpCAM-positive carcinomas treated with i.p. catumaxomab under routine conditions in clinical practice. Participating centres were hospitals and practices of oncologists in Germany. Primary endpoint was puncture-free interval (PFI), secondary endpoints included safety and overall survival (OS). Results: At inclusion into the study pts already had undergone a median number of 9 ascites punctures. Malignant ascites had been diagnosed for the first time 3.3 months before (median). Patients suffered from typical ascites symptoms as follows: swelling (79.6%), pain (44.9%), dyspnea (26.5%), anorexia (26.5%), obstipation (12.2%). 49 pts were treated with catumaxomab, of whom 30 pts received all 4 infusions (61.2%). Median PFI was 108 days (d), the median OS was 102 d. Most frequent adverse events were fever, nausea and diarrhoe. Conclusions: This is the first systematic report on routine use of catumaxomab in clinical practice.. Although The study population mainly comprised patients with advanced tumor diseaset a clinical benefit after catumaxomab therapy could be demonstrated. The treatment showed an acceptable safety profile Theseresults are consistent with the data of the pivotal trial. The data will be evaluated in further analyses including larger patient numbers.

Application of compressed sensing to in vivo 3D ¹⁹F CSI

This study shows how applying compressed sensing (CS) to (19)F chemical shift imaging (CSI) makes highly accurate and reproducible reconstructions from undersampled datasets possible. The missing background signal in (19)F CSI provides the required sparsity needed for application of CS. Simulations were performed to test the influence of different CS-related parameters on reconstruction quality. To test the proposed method on a realistic signal distribution, the simulation results were validated by ex vivo experiments. Additionally, undersampled in vivo 3D CSI mouse datasets were successfully reconstructed using CS. The study results suggest that CS can be used to accurately and reproducibly reconstruct undersampled (19)F spectroscopic datasets. Thus, the scanning time of in vivo(19)F CSI experiments can be significantly reduced while preserving the ability to distinguish between different (19)F markers. The gain in scan time provides high flexibility in adjusting measurement parameters. These features make this technique a useful tool for multiple biological and medical applications.

[Feasibilities and limitations of high field parallel MRI]

In medical magnetic resonance imaging (MRI) it is standard to use MR scanners with a field strength of 1.5 Tesla. Recently, an ongoing development to higher field strength can be observed and a new clinical standard at 3.0 Tesla seems to be established. High field MRI with its intrinsic higher signal to noise ratio (SNR) can enable new applications of MRI in medical diagnosis, or can serve to improve existing methods. It is important to note, that the use of high field MRI is not without its limitations. Besides the SNR, other unwanted effects increase with a higher field strength. Without correction, these high field problems cause a serious loss in image quality. An elegant way to address these problems is the use of parallel imaging. In many clinical applications, parallel MRI (pMRI) is part of the standard protocol, because pMRI can enhance virtually every MRI application, without necessarily affecting the contrast behavior of the underlying imaging sequence. In high field MRI, besides the speed advantage of pMRI, the positive influence on high field specific problems and therefore on the image quality will be of major importance.

Micronucleus yield and colorimetric test as indicators of damage in patients' lymphocytes after 131I therapy

To estimate the absorbed dose received by patients who underwent 131I therapy, a modified compartmental model of the International Commission on Radiological Protection (ICRP) was used. The activity in plasma and micronucleus (MN) frequency (MN test) were measured before and after therapy. To evaluate whether a correlation exists between lymphocytes and absorbed dose, a colorimetric test, based on the tetrazolium salt 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT test), was used.

METHODS

Twenty patients who underwent 131I therapy were studied. Activity was measured in plasma, and isolated lymphocytes were collected to perform the MN and MTT tests.

RESULTS

The mean MN frequency observed in unexposed patient lymphocytes was comparable with that of healthy subjects. 131I therapy induces a small increase in MN, and a good correlation with the bone marrow absorbed dose was obtained (P = 0.040). A consistent decrease in phytostimulation observed after therapy (MTT test) correlated significantly with bone marrow absorbed dose (P = 0.0085).

CONCLUSION

The MTT test appears to be more reliable than the MN test for evaluating lymphocyte damage induced by 131I therapy.

Functional identification of an Arabidopsis snf4 ortholog by screening for heterologous multicopy suppressors of snf4 deficiency in yeast

Yeast Snf4 is a prototype of activating gamma-subunits of conserved Snf1/AMPK-related protein kinases (SnRKs) controlling glucose and stress signaling in eukaryotes. The catalytic subunits of Arabidopsis SnRKs, AKIN10 and AKIN11, interact with Snf4 and suppress the snf1 and snf4 mutations in yeast. By expression of an Arabidopsis cDNA library in yeast, heterologous multicopy snf4 suppressors were isolated. In addition to AKIN10 and AKIN11, the deficiency of yeast snf4 mutant to grown on non-fermentable carbon source was suppressed by Arabidopsis Myb30, CAAT-binding factor Hap3b, casein kinase I, zinc-finger factors AZF2 and ZAT10, as well as orthologs of hexose/UDP-hexose transporters, calmodulin, SMC1-cohesin and Snf4. Here we describe the characterization of AtSNF4, a functional Arabidopsis Snf4 ortholog, that interacts with yeast Snf1 and specifically binds to the C-terminal regulatory domain of Arabidopsis SnRKs AKIN10 and AKIN11.

Ectopic thymus presenting as a solid submandibular neck mass in an infant: case report and review of literature

Solid ectopic cervical thymus is an extremely uncommon etiology of a neck mass in an infant. It occurs in the line of descent of the thymus from the angle of the mandible to the superior mediastinum. Nine cases of ectopic cervical thymus in infants have been reported in the literature. Only two of nine cases were solid, the remaining seven were thymic cysts. A preoperative diagnosis is seldom considered and is often misdiagnosed as a possible malignancy or a lymph node. We present a case of a 2-month-old infant with an asymptomatic enlarging right neck mass. Patient underwent complete excision of the mass.

Indium-111-oxine labeled leukocyte uptake in Ki-1-positive anaplastic large cell lymphoma

Indium-111-oxine labeled leukocyte ((111)In-WBC) scintigraphy is well known for its ability to localize in areas of active infection, but not in areas of lymphomatous involvement. We present a case of Ki-1-positive anaplastic large-cell lymphoma that was initially thought to be a case of multifocal osteomyelitis because of positive uptake on a (111)In-WBC scan. The areas of abnormal uptake on the indium scan were demonstrated histopathologically to be sites of lymphomatous involvement in bone.

Interferon-gamma treatment in mice experimentally infected with Trichinella spiralis

Interferon-tau (IFN-tau) treatment of Trichinella spiralis-infected BALB/c mice was investigated. The therapeutic regimen consisted of daily intraperitoneal injection of 10(4) U murine IFN-tau for 7 days, starting at 2 weeks post-infection. Striated muscle samples (diaphragm, thigh) were collected at 4, 8 and 12 weeks after infection. The muscle larval burden, the degree of encystation and the digestion of T. spiralis larvae were investigated. Furthermore, immunohistochemical studies of the inflammatory cell infiltrate around encysted larvae were performed. The results demonstrated an influence of IFN-tau treatment on the CD4+ and CD8+ subset distribution during the immune response but revealed no difference in the degree of encystation or digestion of encapsulated larvae as compared with control values.

[Endoscopic sphincterotomy in choledocholithiasis (author's transl)]

43 patients had 51 endoscopic sphincterotomies within 4 years; there were 2 complications, 7 patients had to have surgery in spite of endoscopic sphincterotomy. Stones, which had been left unnoticed in the choledochus during surgery could be removed in all cases endoscopically. These results speak in favour of endoscopic sphincterotomy, if compared to results of other non-operative treatments of retained bile duct stones such as percutaneous stone extraction. Endoscopic sphincterotomy has been widely used meanwhile and may be apt now to be introduced as a routine procedure also in smaller hospitals.