scholarly journals A Reliable Method for Rhythm Analysis during Cardiopulmonary Resuscitation

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
U. Ayala ◽  
U. Irusta ◽  
J. Ruiz ◽  
T. Eftestøl ◽  
J. Kramer-Johansen ◽  
...  

Interruptions in cardiopulmonary resuscitation (CPR) compromise defibrillation success. However, CPR must be interrupted to analyze the rhythm because although current methods for rhythm analysis during CPR have high sensitivity for shockable rhythms, the specificity for nonshockable rhythms is still too low. This paper introduces a new approach to rhythm analysis during CPR that combines two strategies: a state-of-the-art CPR artifact suppression filter and a shock advice algorithm (SAA) designed to optimally classify the filtered signal. Emphasis is on designing an algorithm with high specificity. The SAA includes a detector for low electrical activity rhythms to increase the specificity, and a shock/no-shock decision algorithm based on a support vector machine classifier using slope and frequency features. For this study, 1185 shockable and 6482 nonshockable 9-s segments corrupted by CPR artifacts were obtained from 247 patients suffering out-of-hospital cardiac arrest. The segments were split into a training and a test set. For the test set, the sensitivity and specificity for rhythm analysis during CPR were 91.0% and 96.6%, respectively. This new approach shows an important increase in specificity without compromising the sensitivity when compared to previous studies.

2014 ◽  
Vol 2014 ◽  
pp. 1-13 ◽  
Author(s):  
Sofia Ruiz de Gauna ◽  
Unai Irusta ◽  
Jesus Ruiz ◽  
Unai Ayala ◽  
Elisabete Aramendi ◽  
...  

Survival from out-of-hospital cardiac arrest depends largely on two factors: early cardiopulmonary resuscitation (CPR) and early defibrillation. CPR must be interrupted for a reliable automated rhythm analysis because chest compressions induce artifacts in the ECG. Unfortunately, interrupting CPR adversely affects survival. In the last twenty years, research has been focused on designing methods for analysis of ECG during chest compressions. Most approaches are based either on adaptive filters to remove the CPR artifact or on robust algorithms which directly diagnose the corrupted ECG. In general, all the methods report low specificity values when tested on short ECG segments, but how to evaluate the real impact on CPR delivery of continuous rhythm analysis during CPR is still unknown. Recently, researchers have proposed a new methodology to measure this impact. Moreover, new strategies for fast rhythm analysis during ventilation pauses or high-specificity algorithms have been reported. Our objective is to present a thorough review of the field as the starting point for these late developments and to underline the open questions and future lines of research to be explored in the following years.


2004 ◽  
Vol 70 (2) ◽  
pp. 1245-1248 ◽  
Author(s):  
Irina I. Vlasova ◽  
Tatyana V. Asrieli ◽  
Elisaveta M. Gavrilova ◽  
Vadim S. Danilov

ABSTRACT This paper describes a possible application of luminescent Escherichia coli activated by blood serum for high-sensitivity and high-specificity assays of antibiotics in solutions. Antibiotics inhibited luminescence of a genetically engineered E. coli strain; the system sensitivity to some antibiotics grew notably after the cells had been preactivated by blood serum. The highest level of sensitivity (2.8 ± 0.6 ng/ml) of luminescent cells was obtained for aminoglycoside antibiotics (gentamicin and streptomycin). It is feasible to create the specific biosensor for antibiotics on the basis of bioluminescent E. coli strains by applying sera containing antibodies against the antibiotic under assay. The presence of antibodies specific for gentamicin in serum affects inhibition of luminescent cells by gentamicin but not inhibition by other antibiotics.


Circulation ◽  
2020 ◽  
Vol 142 (Suppl_4) ◽  
Author(s):  
Jason Coult ◽  
Shiv Bhandari ◽  
Diya Sashidhar ◽  
Thomas Rea ◽  
Jennifer E Blackwood ◽  
...  

Background: Resuscitation from out-of-hospital cardiac arrest (OHCA) due to ventricular fibrillation (VF) typically involves continuous CPR cycles interrupted every 2 minutes for rhythm analysis and potential defibrillation. Quantitative measures of the VF ECG waveform have been proposed to guide therapy for VF arrest because they are associated with myocardial energetics, are dynamic over the course of resuscitation, and predict outcome. However, while VF waveform measures have until recently have required CPR interruption to accurately gauge prognostic status, CPR interruptions are associated with a lower chance of survival. We used a novel waveform measure previously-validated during active CPR to estimate the course of VF status through the 2-minute CPR cycle between consecutive shocks. Methods: We conducted an observational study of patients with VF OHCA who experienced recurrent VF for at least 90 seconds following initial shock. We used the continuous defibrillator ECG to calculate the VF waveform measure as a function of predicted probability of survival-with-intact-neurologic-status at 1-s intervals over the course of resuscitation between shocks. Results: We collected 499 VF ECG segments (≥90 seconds) during CPR from 313 patients. The trajectory of the average prognostic VF measure had a 3-phase time-dependent pattern (Fig. 1). During CPR, the slope of the measure decreased during the initial 25 s of VF (slope = -12%/min) and was relatively flat during the subsequent 65-s interval of VF (slope = +1%/min). Furthermore, slope decreased sharply following the cessation of CPR for rhythm analysis, charge, and shock (slope = -23%/min). Conclusion: On average, a novel VF waveform measure assessed during the scheduled cycle of CPR and rhythm analysis between consecutive shocks was characterized by a period of decline, stabilization, and then decline. Whether these changes in VF status can be used to improve care for individual patients is uncertain.


2020 ◽  
Vol 16 (8) ◽  
pp. 1088-1105
Author(s):  
Nafiseh Vahedi ◽  
Majid Mohammadhosseini ◽  
Mehdi Nekoei

Background: The poly(ADP-ribose) polymerases (PARP) is a nuclear enzyme superfamily present in eukaryotes. Methods: In the present report, some efficient linear and non-linear methods including multiple linear regression (MLR), support vector machine (SVM) and artificial neural networks (ANN) were successfully used to develop and establish quantitative structure-activity relationship (QSAR) models capable of predicting pEC50 values of tetrahydropyridopyridazinone derivatives as effective PARP inhibitors. Principal component analysis (PCA) was used to a rational division of the whole data set and selection of the training and test sets. A genetic algorithm (GA) variable selection method was employed to select the optimal subset of descriptors that have the most significant contributions to the overall inhibitory activity from the large pool of calculated descriptors. Results: The accuracy and predictability of the proposed models were further confirmed using crossvalidation, validation through an external test set and Y-randomization (chance correlations) approaches. Moreover, an exhaustive statistical comparison was performed on the outputs of the proposed models. The results revealed that non-linear modeling approaches, including SVM and ANN could provide much more prediction capabilities. Conclusion: Among the constructed models and in terms of root mean square error of predictions (RMSEP), cross-validation coefficients (Q2 LOO and Q2 LGO), as well as R2 and F-statistical value for the training set, the predictive power of the GA-SVM approach was better. However, compared with MLR and SVM, the statistical parameters for the test set were more proper using the GA-ANN model.


Author(s):  
Christopher Gaisendrees ◽  
Matias Vollmer ◽  
Sebastian G Walter ◽  
Ilija Djordjevic ◽  
Kaveh Eghbalzadeh ◽  
...  

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ruolan Zeng ◽  
Jiyong Deng ◽  
Limin Dang ◽  
Xinliang Yu

AbstractA three-descriptor quantitative structure–activity/toxicity relationship (QSAR/QSTR) model was developed for the skin permeability of a sufficiently large data set consisting of 274 compounds, by applying support vector machine (SVM) together with genetic algorithm. The optimal SVM model possesses the coefficient of determination R2 of 0.946 and root mean square (rms) error of 0.253 for the training set of 139 compounds; and a R2 of 0.872 and rms of 0.302 for the test set of 135 compounds. Compared with other models reported in the literature, our SVM model shows better statistical performance in a model that deals with more samples in the test set. Therefore, applying a SVM algorithm to develop a nonlinear QSAR model for skin permeability was achieved.


Molecules ◽  
2021 ◽  
Vol 26 (2) ◽  
pp. 414
Author(s):  
Krishan Kumar ◽  
Arijit Ghosh

Target-specific biomolecules, monoclonal antibodies (mAb), proteins, and protein fragments are known to have high specificity and affinity for receptors associated with tumors and other pathological conditions. However, the large biomolecules have relatively intermediate to long circulation half-lives (>day) and tumor localization times. Combining superior target specificity of mAbs and high sensitivity and resolution of the PET (Positron Emission Tomography) imaging technique has created a paradigm-shifting imaging modality, ImmunoPET. In addition to metallic PET radionuclides, 124I is an attractive radionuclide for radiolabeling of mAbs as potential immunoPET imaging pharmaceuticals due to its physical properties (decay characteristics and half-life), easy and routine production by cyclotrons, and well-established methodologies for radioiodination. The objective of this report is to provide a comprehensive review of the physical properties of iodine and iodine radionuclides, production processes of 124I, various 124I-labeling methodologies for large biomolecules, mAbs, and the development of 124I-labeled immunoPET imaging pharmaceuticals for various cancer targets in preclinical and clinical environments. A summary of several production processes, including 123Te(d,n)124I, 124Te(d,2n)124I, 121Sb(α,n)124I, 123Sb(α,3n)124I, 123Sb(3He,2n)124I, natSb(α, xn)124I, natSb(3He,n)124I reactions, a detailed overview of the 124Te(p,n)124I reaction (including target selection, preparation, processing, and recovery of 124I), and a fully automated process that can be scaled up for GMP (Good Manufacturing Practices) production of large quantities of 124I is provided. Direct, using inorganic and organic oxidizing agents and enzyme catalysis, and indirect, using prosthetic groups, 124I-labeling techniques have been discussed. Significant research has been conducted, in more than the last two decades, in the development of 124I-labeled immunoPET imaging pharmaceuticals for target-specific cancer detection. Details of preclinical and clinical evaluations of the potential 124I-labeled immunoPET imaging pharmaceuticals are described here.


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