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Wang H, Jaureguibeitia X, Aramendi E, Nichol G, Aufderheide T, Daya MR, Hansen M, Nassal M, Panchal A, Nikollah DA, Alonso E, Carlson J, Schmicker RH, Stephens S, Irusta U, Idris A. Airway Strategy and Ventilation Rates in the Pragmatic Airway Resuscitation Trial. Resuscitation 2022; 176:80-87. [PMID: 35597311 DOI: 10.1016/j.resuscitation.2022.05.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 05/10/2022] [Accepted: 05/12/2022] [Indexed: 11/15/2022]
Abstract
BACKGROUND We sought to describe ventilation rates during out-of-hospital cardiac arrest (OHCA) resuscitation and their associations with airway management strategy and outcomes. METHODS We analyzed continuous end-tidal carbon dioxide capnography data from adult OHCA enrolled in the Pragmatic Airway Resuscitation Trial (PART). Using automated signal processing techniques, we determined continuous ventilation rate for consecutive 10-second epochs after airway insertion. We defined hypoventilation as a ventilation rate <6 breaths/min. We defined hyperventilation as a ventilation rate >12 breaths/min. We compared differences in total and percentage post-airway hyper- and hypoventilation between airway interventions (laryngeal tube (LT) vs. endotracheal intubation (ETI). We also determined associations between hypo-/hyperventilation and OHCA outcomes (ROSC, 72-hour survival, hospital survival, hospital survival with favorable neurologic status). RESULTS Adequate post-airway capnography were available for 1,010 (LT n=714, ETI n=296) of 3,004 patients. Median ventilation rates were: LT 8.0 (IQR 6.5-9.6) breaths/min, ETI 7.9 (6.5-9.7) breaths/min. Total duration and percentage of post-airway time with hypoventilation were similar between LT and ETI: median 1.8 vs. 1.7 minutes, p=0.94; median 10.5% vs. 11.5%, p=0.60. Total duration and percentage of post-airway time with hyperventilation were similar between LT and ETI: median 0.4 vs. 0.4 minutes, p=0.91; median 2.1% vs. 1.9%, p=0.99. Hypo- and hyperventilation exhibited limited associations with OHCA outcomes. CONCLUSION In the PART Trial, EMS personnel delivered post-airway ventilations at rates satisfying international guidelines, with only limited hypo- or hyperventilation. Hypo- and hyperventilation durations did not differ between airway management strategy and exhibited uncertain associations with OCHA outcomes.
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Egusquiza I, Picon A, Irusta U, Bereciartua-Perez A, Eggers T, Klukas C, Aramendi E, Navarra-Mestre R. Analysis of Few-Shot Techniques for Fungal Plant Disease Classification and Evaluation of Clustering Capabilities Over Real Datasets. Front Plant Sci 2022; 13:813237. [PMID: 35356111 PMCID: PMC8959904 DOI: 10.3389/fpls.2022.813237] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 01/26/2022] [Indexed: 05/31/2023]
Abstract
Plant fungal diseases are one of the most important causes of crop yield losses. Therefore, plant disease identification algorithms have been seen as a useful tool to detect them at early stages to mitigate their effects. Although deep-learning based algorithms can achieve high detection accuracies, they require large and manually annotated image datasets that is not always accessible, specially for rare and new diseases. This study focuses on the development of a plant disease detection algorithm and strategy requiring few plant images (Few-shot learning algorithm). We extend previous work by using a novel challenging dataset containing more than 100,000 images. This dataset includes images of leaves, panicles and stems of five different crops (barley, corn, rape seed, rice, and wheat) for a total of 17 different diseases, where each disease is shown at different disease stages. In this study, we propose a deep metric learning based method to extract latent space representations from plant diseases with just few images by means of a Siamese network and triplet loss function. This enhances previous methods that require a support dataset containing a high number of annotated images to perform metric learning and few-shot classification. The proposed method was compared over a traditional network that was trained with the cross-entropy loss function. Exhaustive experiments have been performed for validating and measuring the benefits of metric learning techniques over classical methods. Results show that the features extracted by the metric learning based approach present better discriminative and clustering properties. Davis-Bouldin index and Silhouette score values have shown that triplet loss network improves the clustering properties with respect to the categorical-cross entropy loss. Overall, triplet loss approach improves the DB index value by 22.7% and Silhouette score value by 166.7% compared to the categorical cross-entropy loss model. Moreover, the F-score parameter obtained from the Siamese network with the triplet loss performs better than classical approaches when there are few images for training, obtaining a 6% improvement in the F-score mean value. Siamese networks with triplet loss have improved the ability to learn different plant diseases using few images of each class. These networks based on metric learning techniques improve clustering and classification results over traditional categorical cross-entropy loss networks for plant disease identification.
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Affiliation(s)
- Itziar Egusquiza
- TECNALIA, Basque Research and Technology Alliance (BRTA), Parque Tecnológico de Bizkaia, Derio, Spain
- University of the Basque Country, Bilbao, Spain
| | - Artzai Picon
- TECNALIA, Basque Research and Technology Alliance (BRTA), Parque Tecnológico de Bizkaia, Derio, Spain
- University of the Basque Country, Bilbao, Spain
| | - Unai Irusta
- University of the Basque Country, Bilbao, Spain
| | - Arantza Bereciartua-Perez
- TECNALIA, Basque Research and Technology Alliance (BRTA), Parque Tecnológico de Bizkaia, Derio, Spain
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Wik L, Brattebø G, Østerås Ø, Assmus J, Irusta U, Aramendi E, Mydske S, Skaalhegg T, Christjar Skaiaa S, Thomassen Ø. Physiological effects of providing supplemental air for avalanche victims. A randomised trial. Resuscitation 2022; 172:38-46. [DOI: 10.1016/j.resuscitation.2022.01.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 12/23/2021] [Accepted: 01/11/2022] [Indexed: 11/28/2022]
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Nassal MMJ, Jaureguibeitia X, Aramendi E, Irusta U, Panchal AR, Wang HE, Idris A. Novel application of thoracic impedance to characterize ventilations during cardiopulmonary resuscitation in the pragmatic airway resuscitation trial. Resuscitation 2021; 168:58-64. [PMID: 34506874 PMCID: PMC8928139 DOI: 10.1016/j.resuscitation.2021.08.045] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 08/26/2021] [Accepted: 08/29/2021] [Indexed: 01/23/2023]
Abstract
BACKGROUND Significant challenges exist in measuring ventilation quality during out-of-hospital cardiopulmonary arrest (OHCA) outcomes. Since ventilation is associated with outcomes in cardiac arrest, tools that objectively describe ventilation dynamics are needed. We sought to characterize thoracic impedance (TI) oscillations associated with ventilation waveforms in the Pragmatic Airway Resuscitation Trial (PART). METHODS We analyzed CPR process files collected from adult OHCA enrolled in PART. We limited the analysis to cases with simultaneous capnography ventilation recordings at the Dallas-Fort Worth site. We identified ventilation waveforms in the thoracic impedance signal by applying automated signal processing with adaptive filtering techniques to remove overlying artifacts from chest compressions. We correlated detected ventilations with the end-tidal capnography signals. We determined the amplitudes (Ai, Ae) and durations (Di, De) of both insufflation and exhalation phases. We compared differences between laryngeal tube (LT) and endotracheal intubation (ETI) airway management during mechanical or manual chest compressions using Mann-Whitney U-test. RESULTS We included 303 CPR process cases in the analysis; 209 manual (77 ETI, 132 LT), 94 mechanical (41 ETI, 53 LT). Ventilation Ai and Ae were higher for ETI than LT in both manual (ETI: Ai 0.71 Ω, Ae 0.70 Ω vs LT: Ai 0.46 Ω, Ae 0.45 Ω; p < 0.01 respectively) and mechanical chest compressions (ETI: Ai 1.22 Ω, Ae 1.14 Ω VS LT: Ai 0.74 Ω, Ae 0.68 Ω; p < 0.01 respectively). Ventilations per minute, duration of TI amplitude insufflation and exhalation did not differ among groups. CONCLUSION Compared with LT, ETI thoracic impedance ventilation insufflation and exhalation amplitude were higher while duration did not differ. TI may provide a novel approach to characterizing ventilation during OHCA.
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Affiliation(s)
- Michelle M J Nassal
- Department of Emergency Medicine, The Ohio State University, Columbus, OH, USA
| | - Xabier Jaureguibeitia
- Department of Communication Engineering, BioRes Group, University of the Basque Country, Bilbao, Spain
| | - Elisabete Aramendi
- Department of Communication Engineering, BioRes Group, University of the Basque Country, Bilbao, Spain
| | - Unai Irusta
- Department of Communication Engineering, BioRes Group, University of the Basque Country, Bilbao, Spain
| | - Ashish R Panchal
- Department of Emergency Medicine, The Ohio State University, Columbus, OH, USA
| | - Henry E Wang
- Department of Emergency Medicine, The Ohio State University, Columbus, OH, USA
| | - Ahamed Idris
- Department of Emergency Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
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Jaureguibeitia X, Aramendi E, Irusta U, Alonso E, Aufderheide TP, Schmicker RH, Hansen M, Suchting R, Carlson JN, Idris AH, Wang HE. Methodology and framework for the analysis of cardiopulmonary resuscitation quality in large and heterogeneous cardiac arrest datasets. Resuscitation 2021; 168:44-51. [PMID: 34509553 DOI: 10.1016/j.resuscitation.2021.09.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 09/01/2021] [Accepted: 09/03/2021] [Indexed: 01/19/2023]
Abstract
BACKGROUND Out-of-hospital cardiac arrest (OHCA) data debriefing and clinical research often require the retrospective analysis of large datasets containing defibrillator files from different vendors and clinical annotations by the emergency medical services. AIM To introduce and evaluate a methodology to automatically extract cardiopulmonary resuscitation (CPR) quality data in a uniform and systematic way from OHCA datasets from multiple heterogeneous sources. METHODS A dataset of 2236 OHCA cases from multiple defibrillator models and manufacturers was analyzed. Chest compressions were automatically identified using the thoracic impedance and compression depth signals. Device event time-stamps and clinical annotations were used to set the start and end of the analysis interval, and to identify periods with spontaneous circulation. A manual audit of the automatic annotations was conducted and used as gold standard. Chest compression fraction (CCF), rate (CCR) and interruption ratio were computed as CPR quality variables. The unsigned error between the automated procedure and the gold standard was calculated. RESULTS Full-episode median errors below 2% in CCF, 1 min-1 in CCR, and 1.5% in interruption ratio, were measured for all signals and devices. The proportion of cases with large errors (>10% in CCF and interruption ratio, and >10 min-1 in CCR) was below 10%. Errors were lower for shorter sub-intervals of interest, like the airway insertion interval. CONCLUSIONS An automated methodology was validated to accurately compute CPR metrics in large and heterogeneous OHCA datasets. Automated processing of defibrillator files and the associated clinical annotations enables the aggregation and analysis of CPR data from multiple sources.
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Affiliation(s)
- Xabier Jaureguibeitia
- Communications Engineering Department, University of the Basque Country UPV/EHU, Bilbao, Spain
| | - Elisabete Aramendi
- Communications Engineering Department, University of the Basque Country UPV/EHU, Bilbao, Spain; Biocruces Bizkaia Health Research Institute, Barakaldo, Spain.
| | - Unai Irusta
- Communications Engineering Department, University of the Basque Country UPV/EHU, Bilbao, Spain; Biocruces Bizkaia Health Research Institute, Barakaldo, Spain
| | - Erik Alonso
- Department of Applied Mathematics, University of the Basque Country UPV/EHU, Bilbao, Spain
| | - Tom P Aufderheide
- Department of Emergency Medicine, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Robert H Schmicker
- Clinical Trial Center, Department of Biostatistics, University of Washington, Seattle, WA, United States
| | - Matthew Hansen
- Department of Emergency Medicine, Oregon Health and Science University, Portland, OR, United States
| | - Robert Suchting
- Department of Psychiatry and Behavioral, Sciences University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Jestin N Carlson
- Department of Emergency Medicine, Saint Vincent Hospital, Allegheny Health Network, Erie, PA, United States; Department of Emergency Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Ahamed H Idris
- Department of Emergency Medicine, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Henry E Wang
- Department of Emergency Medicine, Ohio State University, Columbus, OH, United States
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Berve PO, Irusta U, Kramer-Johansen J, Skålhegg T, Aramendi E, Wik L. Tidal volume measurements via transthoracic impedance waveform characteristics: The effect of age, body mass index and gender. A single centre interventional study. Resuscitation 2021; 167:218-224. [PMID: 34480974 DOI: 10.1016/j.resuscitation.2021.08.041] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Revised: 08/20/2021] [Accepted: 08/25/2021] [Indexed: 12/22/2022]
Abstract
BACKGROUND AND AIM Measuring tidal volumes (TV) during bag-valve ventilation is challenging in the clinical setting. The ventilation waveform amplitude of the transthoracic impedance (TTI-amplitude) correlates well with TV for an individual, but poorer between patients. We hypothesized that TV to TTI-amplitude relations could be improved when adjusted for morphometric variables like body mass index (BMI), gender or age, and that TTI-amplitude cut-offs for ventilations with adequate TV (>400ml) could be established. MATERIALS AND METHODS Twenty-one consenting adults (9 female, and 9 overall overweight) during positive pressure ventilation in anaesthesia before scheduled surgery were included. Seventeen ventilator modes were used (⩾ five breaths per mode) to adjust different TVs (150-800 ml), ventilation frequencies (10-30 min-1) and insufflation times (0.5-3.5 s). TTI from the defibrillation pads was filtered to obtain ventilation TTI-amplitudes. Linear regression models were fitted between target and explanatory variables, and compared (coefficient of determination, R2). RESULTS The TV to TTI-amplitude slope was 1.39 Ω/l (R2=0.52), with significant differences (p<0.05) between male/female (1.04 Ω/l vs 1.84 Ω/l) and normal/overweight subjects (1.65 Ω/l vs 1.04 Ω/l). The median (interquartile range) TTI-amplitude cut-off for adequate TV was 0.51 Ω(0.14-1.20) with significant differences between males and females (0.58 Ω/0.39 Ω), and normal and overweight subjects (0.52 Ω/0.46 Ω). The TV to TTI-amplitude model improved (R2=0.66) when BMI, age and gender were included. CONCLUSIONS TTI-amplitude to TV relations were established and cut-offs for ventilations with adequate TV determined. Patient morphometric variables related to gender, age and BMI explain part of the variability in the measurements.
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Affiliation(s)
- P O Berve
- Norwegian National Advisory Unit for Prehospital Emergency Medicine (NAKOS), Oslo University Hospital - Ullevål and University of Oslo, Po Box 4956 Nydalen, N-0424 Oslo, Norway; Air Ambulance Department, Division of Prehospital Services, Oslo University Hospital, Oslo, Norway.
| | - U Irusta
- Communications Engineering Department, University of the Basque Country UPV/EHU, Alameda Urquijo S/N, 48013 Bilbao, Spain; Biocruces Bizkaia Health Research Institute, Cruces Plaza, 48903 Barakaldo, Bizkaia, Spain
| | - J Kramer-Johansen
- Norwegian National Advisory Unit for Prehospital Emergency Medicine (NAKOS), Oslo University Hospital - Ullevål and University of Oslo, Po Box 4956 Nydalen, N-0424 Oslo, Norway; Air Ambulance Department, Division of Prehospital Services, Oslo University Hospital, Oslo, Norway
| | - T Skålhegg
- Air Ambulance Department, Division of Prehospital Services, Oslo University Hospital, Oslo, Norway; Ambulance Department, Division of Prehospital Services, Oslo University Hospital, Oslo, Norway
| | - E Aramendi
- Communications Engineering Department, University of the Basque Country UPV/EHU, Alameda Urquijo S/N, 48013 Bilbao, Spain; Biocruces Bizkaia Health Research Institute, Cruces Plaza, 48903 Barakaldo, Bizkaia, Spain
| | - L Wik
- Norwegian National Advisory Unit for Prehospital Emergency Medicine (NAKOS), Oslo University Hospital - Ullevål and University of Oslo, Po Box 4956 Nydalen, N-0424 Oslo, Norway; Air Ambulance Department, Division of Prehospital Services, Oslo University Hospital, Oslo, Norway
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Urteaga J, Aramendi E, Elola A, Irusta U, Idris A. A Machine Learning Model for the Prognosis of Pulseless Electrical Activity during Out-of-Hospital Cardiac Arrest. Entropy (Basel) 2021; 23:e23070847. [PMID: 34209405 PMCID: PMC8307658 DOI: 10.3390/e23070847] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 06/26/2021] [Accepted: 06/28/2021] [Indexed: 11/16/2022]
Abstract
Pulseless electrical activity (PEA) is characterized by the disassociation of the mechanical and electrical activity of the heart and appears as the initial rhythm in 20–30% of out-of-hospital cardiac arrest (OHCA) cases. Predicting whether a patient in PEA will convert to return of spontaneous circulation (ROSC) is important because different therapeutic strategies are needed depending on the type of PEA. The aim of this study was to develop a machine learning model to differentiate PEA with unfavorable (unPEA) and favorable (faPEA) evolution to ROSC. An OHCA dataset of 1921 5s PEA signal segments from defibrillator files was used, 703 faPEA segments from 107 patients with ROSC and 1218 unPEA segments from 153 patients with no ROSC. The solution consisted of a signal-processing stage of the ECG and the thoracic impedance (TI) and the extraction of the TI circulation component (ICC), which is associated with ventricular wall movement. Then, a set of 17 features was obtained from the ECG and ICC signals, and a random forest classifier was used to differentiate faPEA from unPEA. All models were trained and tested using patientwise and stratified 10-fold cross-validation partitions. The best model showed a median (interquartile range) area under the curve (AUC) of 85.7(9.8)% and a balance accuracy of 78.8(9.8)%, improving the previously available solutions at more than four points in the AUC and three points in balanced accuracy. It was demonstrated that the evolution of PEA can be predicted using the ECG and TI signals, opening the possibility of targeted PEA treatment in OHCA.
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Affiliation(s)
- Jon Urteaga
- Department of Communications Engineering, University of the Basque Country, 48013 Bilbao, Spain; (E.A.); (U.I.)
- Correspondence: ; Tel.: +34-946-01-73-85
| | - Elisabete Aramendi
- Department of Communications Engineering, University of the Basque Country, 48013 Bilbao, Spain; (E.A.); (U.I.)
- Biocruces Bizkaia Health Research Institute, Cruces University Hospital, 48903 Baracaldo, Spain
| | - Andoni Elola
- Department of Mathematics, University of the Basque Country, 48013 Bilbao, Spain;
| | - Unai Irusta
- Department of Communications Engineering, University of the Basque Country, 48013 Bilbao, Spain; (E.A.); (U.I.)
- Biocruces Bizkaia Health Research Institute, Cruces University Hospital, 48903 Baracaldo, Spain
| | - Ahamed Idris
- Department of Emergency Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA;
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Isasi I, Irusta U, Aramendi E, Olsen JA, Wik L. Shock decision algorithm for use during load distributing band cardiopulmonary resuscitation. Resuscitation 2021; 165:93-100. [PMID: 34098032 DOI: 10.1016/j.resuscitation.2021.05.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 05/18/2021] [Accepted: 05/30/2021] [Indexed: 10/21/2022]
Abstract
AIM Chest compressions delivered by a load distributing band (LDB) induce artefacts in the electrocardiogram. These artefacts alter shock decisions in defibrillators. The aim of this study was to demonstrate the first reliable shock decision algorithm during LDB compressions. METHODS The study dataset comprised 5813 electrocardiogram segments from 896 cardiac arrest patients during LDB compressions. Electrocardiogram segments were annotated by consensus as shockable (1154, 303 patients) or nonshockable (4659, 841 patients). Segments during asystole were used to characterize the LDB artefact and to compare its characteristics to those of manual artefacts from other datasets. LDB artefacts were removed using adaptive filters. A machine learning algorithm was designed for the shock decision after filtering, and its performance was compared to that of a commercial defibrillator's algorithm. RESULTS Median (90% confidence interval) compression frequencies were lower and more stable for the LDB than for the manual artefact, 80 min-1 (79.9-82.9) vs. 104.4 min-1 (48.5-114.0). The amplitude and waveform regularity (Pearson's correlation coefficient) were larger for the LDB artefact, with 5.5 mV (0.8-23.4) vs. 0.5 mV (0.1-2.2) (p < 0.001) and 0.99 (0.78-1.0) vs. 0.88 (0.55-0.98) (p < 0.001). The shock decision accuracy was significantly higher for the machine learning algorithm than for the defibrillator algorithm, with sensitivity/specificity pairs of 92.1/96.8% (machine learning) vs. 91.4/87.1% (defibrillator) (p < 0.001). CONCLUSION Compared to other cardiopulmonary resuscitation artefacts, removing the LDB artefact was challenging due to larger amplitudes and lower compression frequencies. The machine learning algorithm achieved clinically reliable shock decisions during LDB compressions.
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Affiliation(s)
- I Isasi
- Communications Engineering Department, University of the Basque Country UPV/EHU, Plaza Ingeniero Torres Quevedo S/N, 48013 Bilbao, Bizkaia, Spain
| | - U Irusta
- Communications Engineering Department, University of the Basque Country UPV/EHU, Plaza Ingeniero Torres Quevedo S/N, 48013 Bilbao, Bizkaia, Spain; Biocruces Bizkaia Health Research Institute, Cruces Plaza, 48903 Barakaldo, Bizkaia, Spain
| | - E Aramendi
- Communications Engineering Department, University of the Basque Country UPV/EHU, Plaza Ingeniero Torres Quevedo S/N, 48013 Bilbao, Bizkaia, Spain; Biocruces Bizkaia Health Research Institute, Cruces Plaza, 48903 Barakaldo, Bizkaia, Spain
| | - J A Olsen
- National Advisory Unit for Prehospital Emergency Medicine (NAKOS) and Department of Anaesthesiology, Oslo University Hospital and University of Oslo, PO Box 4956 Nydalen, N-0424 Oslo, Norway
| | - L Wik
- National Advisory Unit for Prehospital Emergency Medicine (NAKOS) and Department of Anaesthesiology, Oslo University Hospital and University of Oslo, PO Box 4956 Nydalen, N-0424 Oslo, Norway
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Elola A, Aramendi E, Irusta U, Berve PO, Wik L. Multimodal Algorithms for the Classification of Circulation States During Out-of-Hospital Cardiac Arrest. IEEE Trans Biomed Eng 2021; 68:1913-1922. [PMID: 33044927 DOI: 10.1109/tbme.2020.3030216] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
GOAL Identifying the circulation state during out-of-hospital cardiac arrest (OHCA) is essential to determine what life-saving therapies to apply. Currently algorithms discriminate circulation (pulsed rhythms, PR) from no circulation (pulseless electrical activity, PEA), but PEA can be classified into true (TPEA) and pseudo (PPEA) depending on cardiac contractility. This study introduces multi-class algorithms to automatically determine circulation states during OHCA using the signals available in defibrillators. METHODS A cohort of 60 OHCA cases were used to extract a dataset of 2506 5-s segments, labeled as PR (1463), PPEA (364) and TPEA (679) using the invasive blood pressure, experimentally recorded through a radial/femoral cannulation. A multimodal algorithm using features obtained from the electrocardiogram, the thoracic impedance and the capnogram was designed. A random forest model was trained to discriminate three (TPEA/PPEA/PR) and two (PEA/PR) circulation states. The models were evaluated using repeated patient-wise 5-fold cross-validation, with the unweighted mean of sensitivities (UMS) and F 1-score as performance metrics. RESULTS The best model for 3-class had a median (interquartile range, IQR) UMS and F 1 of 69.0% (68.0-70.1) and 61.7% (61.0-62.5), respectively. The best two class classifier had median (IQR) UMS and F 1 of 83.9% (82.9-84.5) and 76.2% (75.0-76.9), outperforming all previous proposals in over 3-points in UMS. CONCLUSIONS The first multiclass OHCA circulation state classifier was demonstrated. The method improved previous algorithms for binary pulse/no-pulse decisions. SIGNIFICANCE Automatic multiclass circulation state classification during OHCA could contribute to improve cardiac arrest therapy and improve survival rates.
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Wang HE, Jaureguibeitia X, Aramendi E, Jarvis JL, Carlson JN, Irusta U, Alonso E, Aufderheide T, Schmicker RH, Hansen ML, Huebinger RM, Colella MR, Gordon R, Suchting R, Idris AH. Airway strategy and chest compression quality in the Pragmatic Airway Resuscitation Trial. Resuscitation 2021; 162:93-98. [PMID: 33582258 DOI: 10.1016/j.resuscitation.2021.01.043] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 01/15/2021] [Accepted: 01/28/2021] [Indexed: 11/18/2022]
Abstract
BACKGROUND Chest compression (CC) quality is associated with improved out-of-hospital cardiopulmonary arrest (OHCA) outcomes. Airway management efforts may adversely influence CC quality. We sought to compare the effects of initial laryngeal tube (LT) and initial endotracheal intubation (ETI) airway management strategies upon chest compression fraction (CCF), rate and interruptions in the Pragmatic Airway Resuscitation Trial (PART). METHODS We analyzed CPR process files collected from adult OHCA enrolled in PART. We used automated signal processing techniques and a graphical user interface to calculate CC quality measures and defined interruptions as pauses in chest compressions longer than 3 s. We determined CC fraction, rate and interruptions (number and total duration) for the entire resuscitation and compared differences between LT and ETI using t-tests. We repeated the analysis stratified by time before, during and after airway insertion as well as by successive 3-min time segments. We also compared CC quality between single vs. multiple airway insertion attempts, as well as between bag-valve-mask (BVM-only) vs. ETI or LT. RESULTS Of 3004 patients enrolled in PART, CPR process data were available for 1996 (1001 LT, 995 ETI). Mean CPR analysis duration were: LT 22.6 ± 10.8 min vs. ETI 25.3 ± 11.3 min (p < 0.001). Mean CC fraction (LT 88% vs. ETI 87%, p = 0.05) and rate (LT 114 vs. ETI 114 compressions per minute (cpm), p = 0.59) were similar between LT and ETI. Median number of CC interruptions were: LT 11 vs. ETI 12 (p = 0.001). Total CC interruption duration was lower for LT than ETI (LT 160 vs. ETI 181 s, p = 0.002); this difference was larger before airway insertion (LT 56 vs. ETI 78 s, p < 0.001). There were no differences in CC quality when stratified by 3-min time epochs. CONCLUSION In the PART trial, compared with ETI, LT was associated with shorter total CC interruption duration but not other CC quality measures. CC quality may be associated with OHCA airway management.
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Affiliation(s)
- Henry E Wang
- Department of Emergency Medicine, The University of Texas Health Science Center at Houston, Houston, TX, United States.
| | - Xabier Jaureguibeitia
- Department of Communication Engineering, BioRes Group, University of the Basque Country, Bilbao, Spain
| | - Elisabete Aramendi
- Department of Communication Engineering, BioRes Group, University of the Basque Country, Bilbao, Spain
| | - Jeffrey L Jarvis
- Williamson County Emergency Medical Services, Georgetown, TX, United States; Department of Emergency Medicine, The University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Jestin N Carlson
- Department of Emergency Medicine, The University of Pittsburgh, Pittsburgh, PA, United States
| | - Unai Irusta
- Department of Communication Engineering, BioRes Group, University of the Basque Country, Bilbao, Spain
| | - Erik Alonso
- Department of Applied Mathematics, University of the Basque Country, Bilbao, Spain
| | - Tom Aufderheide
- Department of Emergency Medicine, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Robert H Schmicker
- Center for Biomedical Statistics, The University of Washington, Seattle, WA, United States
| | - Matthew L Hansen
- Department of Emergency Medicine, Oregon Health & Science University, Portland, OR, United States
| | - Ryan M Huebinger
- Department of Emergency Medicine, The University of Texas Health Science Center at Houston, Houston, TX, United States
| | - M Riccardo Colella
- Department of Emergency Medicine, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Richard Gordon
- Department of Emergency Medicine, The University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Robert Suchting
- Department of Psychiatry and Behavioral Sciences, The University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Ahamed H Idris
- Department of Emergency Medicine, University of Texas Southwestern Medical Center, Dallas, TX, United States
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11
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Frigerio L, Baldi E, Aramendi E, Chicote B, Irusta U, Contri E, Palo A, Compagnoni S, Fracchia R, Iotti G, Oltrona Visconti L, Savastano S. End-tidal carbon dioxide (ETCO 2) and ventricular fibrillation amplitude spectral area (AMSA) for shock outcome prediction in out-of-hospital cardiac arrest. Are they two sides of the same coin? Resuscitation 2020; 160:142-149. [PMID: 33181229 DOI: 10.1016/j.resuscitation.2020.10.032] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 09/15/2020] [Accepted: 10/19/2020] [Indexed: 11/15/2022]
Abstract
AIM Ventricular fibrillation amplitude spectral area (AMSA) and end-tidal carbon dioxide (ETCO2) are predictors of shock success, understood as restoration of an organized rhythm, and return of spontaneous circulation (ROSC). However, little is known about their combined use. We aimed to assess the prediction accuracy when combined, and to clarify if they are correlated in out of hospital cardiac arrest' victims. MATERIALS AND METHODS Records acquired by external defibrillators in out-of-hospital cardiac arrest patients of the Lombardia Cardiac Arrest registry were processed. The 1-min pre-shock ETCO2 median value (METCO2) was computed from the capnogram and AMSA (2-48 mV.Hz range) computed applying the Fast Fourier Transform to a 2-second pre-shock filtered ECG interval (0.5-30 Hz). Support Vector Machine (SVM) predictive models based on METCO2, AMSA and their combination were fit; results were given as the area under the curve (AUC) of the receiver operating characteristic (ROC) curves. RESULTS We considered 112 patients with 391 shocks delivered. METCO2 and AMSA were predictors of shock success [AUC (IQR) of the ROC curve: 0.59 (0.56-0.62); 0.68 (0.65-0.72), respectively] and of ROSC [0.56 (0.53-0.59); 0.74 (0.71-0.78),]. Their combination in a SVM model increased the accuracy for predicting shock success [AUC (IQR) of the ROC curve: 0.71 (0.68-0.75)] and ROSC [0.77 (0.73-0.8)]. AMSA and METCO2 were significantly correlated only in patients who achieved ROSC (rho = 0.33 p = 0.03). CONCLUSIONS AMSA and ETCO2 predict shock success and ROSC after every shock, and their predictive power increases if combined. Notably, they were correlated only in patients who achieved ROSC.
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Affiliation(s)
- Laura Frigerio
- Division of Cardiology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Enrico Baldi
- Cardiac Intensive Care Unit, Arrhythmia and Electrophysiology and Experimental Cardiology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, Section of Cardiology, University of Pavia, Pavia, Italy
| | - Elisabete Aramendi
- Communications Engineering Department, University of the Basque Country UPV/EHU, Bilbao, Spain
| | - Beatriz Chicote
- Communications Engineering Department, University of the Basque Country UPV/EHU, Bilbao, Spain
| | - Unai Irusta
- Communications Engineering Department, University of the Basque Country UPV/EHU, Bilbao, Spain
| | - Enrico Contri
- AREU Azienda Regionale Emergenza Urgenza - AAT Pavia c/o Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Alessandra Palo
- AREU Azienda Regionale Emergenza Urgenza - AAT Pavia c/o Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Sara Compagnoni
- Division of Cardiology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; Department of Molecular Medicine, Section of Cardiology, University of Pavia, Pavia, Italy
| | - Rosa Fracchia
- Division of Cardiology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Giorgio Iotti
- Intensive Care Unit, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | | | - Simone Savastano
- Division of Cardiology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.
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12
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Isasi I, Irusta U, Aramendi E, Idris AH, Sörnmo L. Restoration of the electrocardiogram during mechanical cardiopulmonary resuscitation. Physiol Meas 2020; 41:105006. [DOI: 10.1088/1361-6579/ab9e53] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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13
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Isasi I, Irusta U, Aramendi E, Eftestøl T, Kramer-Johansen J, Wik L. Rhythm Analysis during Cardiopulmonary Resuscitation Using Convolutional Neural Networks. Entropy (Basel) 2020; 22:E595. [PMID: 33286367 PMCID: PMC7845778 DOI: 10.3390/e22060595] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 05/25/2020] [Accepted: 05/26/2020] [Indexed: 12/18/2022]
Abstract
Chest compressions during cardiopulmonary resuscitation (CPR) induce artifacts in the ECG that may provoque inaccurate rhythm classification by the algorithm of the defibrillator. The objective of this study was to design an algorithm to produce reliable shock/no-shock decisions during CPR using convolutional neural networks (CNN). A total of 3319 ECG segments of 9 s extracted during chest compressions were used, whereof 586 were shockable and 2733 nonshockable. Chest compression artifacts were removed using a Recursive Least Squares (RLS) filter, and the filtered ECG was fed to a CNN classifier with three convolutional blocks and two fully connected layers for the shock/no-shock classification. A 5-fold cross validation architecture was adopted to train/test the algorithm, and the proccess was repeated 100 times to statistically characterize the performance. The proposed architecture was compared to the most accurate algorithms that include handcrafted ECG features and a random forest classifier (baseline model). The median (90% confidence interval) sensitivity, specificity, accuracy and balanced accuracy of the method were 95.8% (94.6-96.8), 96.1% (95.8-96.5), 96.1% (95.7-96.4) and 96.0% (95.5-96.5), respectively. The proposed algorithm outperformed the baseline model by 0.6-points in accuracy. This new approach shows the potential of deep learning methods to provide reliable diagnosis of the cardiac rhythm without interrupting chest compression therapy.
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Affiliation(s)
- Iraia Isasi
- Department of Communications Engineering, University of the Basque Country UPV/EHU, 48013 Bilbao, Spain; (U.I.); (E.A.)
| | - Unai Irusta
- Department of Communications Engineering, University of the Basque Country UPV/EHU, 48013 Bilbao, Spain; (U.I.); (E.A.)
| | - Elisabete Aramendi
- Department of Communications Engineering, University of the Basque Country UPV/EHU, 48013 Bilbao, Spain; (U.I.); (E.A.)
| | - Trygve Eftestøl
- Department of Electrical Engineering and Computer Science, University of Stavanger, 4036 Stavanger, Norway;
| | - Jo Kramer-Johansen
- Norwegian National Advisory Unit on Prehospital Emergency Medicine (NAKOS), Oslo University Hospital and University of Oslo, 0424 Oslo, Norway; (J.K.-J.); (L.W.)
| | - Lars Wik
- Norwegian National Advisory Unit on Prehospital Emergency Medicine (NAKOS), Oslo University Hospital and University of Oslo, 0424 Oslo, Norway; (J.K.-J.); (L.W.)
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14
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Skogvoll E, Nordseth T, Sutton RM, Eftestøl T, Irusta U, Aramendi E, Niles D, Nadkarni V, Berg RA, Abella BS, Kvaløy JT. Factors affecting the course of resuscitation from cardiac arrest with pulseless electrical activity in children and adolescents. Resuscitation 2020; 152:116-122. [PMID: 32433939 DOI: 10.1016/j.resuscitation.2020.05.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 03/17/2020] [Accepted: 05/07/2020] [Indexed: 02/08/2023]
Abstract
BACKGROUND Although in-hospital pediatric cardiac arrests and cardiopulmonary resuscitation occur >15,000/year in the US, few studies have assessed which factors affect the course of resuscitation in these patients. We investigated transitions from Pulseless Electrical Activity (PEA) to Ventricular Fibrillation/pulseless Ventricular Tachycardia (VF/pVT), Return of Spontaneous Circulation (ROSC) and recurrences from ROSC to PEA in children and adolescents with in-hospital cardiac arrest. METHODS Episodes of cardiac arrest at the Children's Hospital of Philadelphia were prospectively registered. Defibrillators that recorded chest compression depth/rate and ventilation rate were applied. CPR variables, patient characteristics and etiology, and dynamic factors (e.g. the proportion of time spent in PEA or ROSC) were entered as time-varying covariates for the transition intensities under study. RESULTS In 67 episodes of CPR in 59 patients (median age 15 years) with cardiac arrest, there were 52 transitions from PEA to ROSC, 22 transitions from PEA to VF/pVT, and 23 recurrences of PEA from ROSC. Except for a nearly significant effect of mean compression depth beyond a threshold of 5.7 cm, only dynamic factors that evolved during CPR favored a transition from PEA to ROSC. The latter included a lower proportion of PEA over the last 5 min and a higher proportion of ROSC over the last 5 min. Factors associated with PEA to VF/pVT development were age, weight, the proportion spent in VF/pVT or PEA the last 5 min, and the general transition intensity, while PEA recurrence from ROSC only depended on the general transition intensity. CONCLUSION The clinical course during pediatric cardiac arrest was mainly influenced by dynamic factors associated with time in PEA and ROSC. Transitions from PEA to ROSC seemed to be favored by deeper compressions.
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Affiliation(s)
- Eirik Skogvoll
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway; Clinic of Anesthesia and Intensive Care Medicine, St. Olav's University Hospital, Trondheim, Norway.
| | - Trond Nordseth
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway; Molde Hospital Trust, Molde, Norway; Department of Emergency Medicine and Prehospital Services, St. Olav's University Hospital, Trondheim, Norway
| | - Robert M Sutton
- Children's Hospital of Philadelphia, USA; Center for Resuscitation Science, University of Pennsylvania, Philadelphia, USA
| | - Trygve Eftestøl
- Department of Electrical Engineering and Computer Science, University of Stavanger, Norway
| | - Unai Irusta
- University of the Basque Country, Bilbao, Spain
| | | | - Dana Niles
- Children's Hospital of Philadelphia, USA
| | - Vinay Nadkarni
- Children's Hospital of Philadelphia, USA; Center for Resuscitation Science, University of Pennsylvania, Philadelphia, USA
| | - Robert A Berg
- Children's Hospital of Philadelphia, USA; Center for Resuscitation Science, University of Pennsylvania, Philadelphia, USA
| | - Benjamin S Abella
- Center for Resuscitation Science, University of Pennsylvania, Philadelphia, USA
| | - Jan Terje Kvaløy
- Department of Mathematics and Physics, University of Stavanger, Norway
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Isasi I, Irusta U, Elola A, Aramendi E, Eftestol T, Kramer-Johansen J, Wik L. A Robust Machine Learning Architecture for a Reliable ECG Rhythm Analysis during CPR. Annu Int Conf IEEE Eng Med Biol Soc 2020; 2019:1903-1907. [PMID: 31946270 DOI: 10.1109/embc.2019.8856784] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Chest compressions delivered during cardiopulmonary resuscitation (CPR) induce artifacts in the ECG that may make the shock advice algorithms (SAA) of defibrillators inaccurate. There is evidence that methods consisting of adaptive filters that remove the CPR artifact followed by machine learning (ML) based algorithms are able to make reliable shock/no-shock decisions during compressions. However, there is room for improvement in the performance of these methods. The objective was to design a robust ML framework for a reliable shock/no-shock decision during CPR. The study dataset contained 596 shockable and 1697 nonshockable ECG segments obtained from 273 cases of out-of-hospital cardiac arrest. Shock/no-shock labels were adjudicated by expert reviewers using ECG intervals without artifacts. First, CPR artifacts were removed from the ECG using a Least Mean Squares (LMS) filter. Then, 38 shock/no-shock decision features based on the Stationary Wavelet Transform (SWT) were extracted from the filtered ECG. A wapper-based feature selection method was applied to select the 6 best features for classification. Finally, 4 state-of-the-art ML classifiers were tested to make the shock/no-shock decision. These diagnoses were compared with the rhythm annotations to compute the Sensitivity (Se) and Specificity (Sp). All classifiers achieved an Se above 94.5%, Sp above 95.5% and an accuracy around 96.0%. They all exceeded the 90% Se and 95% Sp minimum values recommended by the American Heart Association.
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16
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Jaureguibeitia X, Irusta U, Aramendi E, Owens PC, Wang HE, Idris AH. Automatic Detection of Ventilations During Mechanical Cardiopulmonary Resuscitation. IEEE J Biomed Health Inform 2020; 24:2580-2588. [PMID: 31976918 DOI: 10.1109/jbhi.2020.2967643] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Feedback on chest compressions and ventilations during cardiopulmonary resuscitation (CPR) is important to improve survival from out-of-hospital cardiac arrest (OHCA). The thoracic impedance signal acquired by monitor-defibrillators during treatment can be used to provide feedback on ventilations, but chest compression components prevent accurate detection of ventilations. This study introduces the first method for accurate ventilation detection using the impedance while chest compressions are concurrently delivered by a mechanical CPR device. A total of 423 OHCA patients treated with mechanical CPR were included, 761 analysis intervals were selected which in total comprised 5 884 minutes and contained 34 864 ventilations. Ground truth ventilations were determined using the expired CO 2 channel. The method uses adaptive signal processing to obtain the impedance ventilation waveform. Then, 14 features were calculated from the ventilation waveform and fed to a random forest (RF) classifier to discriminate false positive detections from actual ventilations. The RF feature importance was used to determine the best feature subset for the classifier. The method was trained and tested using stratified 10-fold cross validation (CV) partitions. The training/test process was repeated 20 times to statistically characterize the results. The best ventilation detector had a median (interdecile range, IDR) F 1-score of 96.32 (96.26-96.37). When used to provide feedback in 1-min intervals, the median (IDR) error and relative error in ventilation rate were 0.002 (-0.334-0.572) min-1 and 0.05 (-3.71-9.08)%, respectively. An accurate ventilation detector during mechanical CPR was demonstrated. The algorithm could be introduced in current equipment for feedback on ventilation rate and quality, and it could contribute to improve OHCA survival rates.
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17
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Manibardo E, Irusta U, Ser JD, Aramendi E, Isasi I, Olabarria M, Corcuera C, Veintemillas J, Larrea A. ECG-based Random Forest Classifier for Cardiac Arrest Rhythms. Annu Int Conf IEEE Eng Med Biol Soc 2020; 2019:1504-1508. [PMID: 31946179 DOI: 10.1109/embc.2019.8857893] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Rhythm annotation of out-of-hospital cardiac episodes (OHCA) is key for a better understanding of the interplay between resuscitation therapy and OHCA patient outcome. OHCA rhythms are classified in five categories, asystole (AS), pulseless electrical activity (PEA), pulsed rhythms (PR), ventricular fibrillation (VF) and ventricular tachycardia (VT). Manual OHCA annotation by expert clinicians is onerous and time consuming, so there is a need for accurate and automatic OHCA rhythm annotation methods. For this study 852 OHCA episodes of patients treated with Automated External Defibrillators (AED) by the Emergency Medical Services of the Basque Country were analyzed. Six expert clinicians reviewed the electrocardiogram (ECG) of 4214 AED rhythm analyses and annotated the rhythm. Their consensus decision was used as ground truth. There were a total of 2418 AS, 294 PR, 1008 PEA, 472 VF and 22 VT. The ECG analysis intervals were extracted and used to develop an automatic rhythm annotator. Data was partitioned patient-wise into training (70%) and test (30%). Performance was evaluated in terms of per class sensitivity (Se) and F-score (F1). The unweighted mean of sensitivity (UMS) and F-score were used as global performance metrics. The classification method is composed of a feature extraction and denoising stage based on the stationary wavelet transform of the ECG, and on a random forest classifier. The best model presented a per rhythm Se/F1 of 95.8/95.7, 43.3/52.2, 85.3/81.3, 94.2/96.1, 81.9/72.2 for AS, PR, PEA, VF and VT, respectively. The UMS for the test set was 80.2%, 2-points above that of previous solutions. This method could be used to retrospectively annotate large OHCA datasets and ameliorate the workload of manual OHCA rhythm annotation.
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18
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Elola A, Aramendi E, Irusta U, Picon A, Alonso E, Isasi I, Idris A. Convolutional Recurrent Neural Networks to Characterize the Circulation Component in the Thoracic Impedance during Out-of-Hospital Cardiac Arrest. Annu Int Conf IEEE Eng Med Biol Soc 2020; 2019:1921-1925. [PMID: 31946274 DOI: 10.1109/embc.2019.8857758] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Pulse detection during out-of-hospital cardiac arrest remains challenging for both novel and expert rescuers because current methods are inaccurate and time-consuming. There is still a need to develop automatic methods for pulse detection, where the most challenging scenario is the discrimination between pulsed rhythms (PR, pulse) and pulseless electrical activity (PEA, no pulse). Thoracic impedance (TI) acquired through defibrillation pads has been proven useful for detecting pulse as it shows small fluctuations with every heart beat. In this study we analyse the use of deep learning techniques to detect pulse using only the TI signal. The proposed neural network, composed by convolutional and recurrent layers, outperformed state of the art methods, and achieved a balanced accuracy of 90% for segments as short as 3 s.
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Larrea A, Salaberria R, Amas L, Alonso D, Blanco U, Casas J, Andonegui A, Garmendia I, Aramendi E, Irusta U. Haemoglobin concentration measured by high time resolution cerebral oximetry can monitor chest compression frequency in out-of-hospital cardiac arrest. Resuscitation 2019. [DOI: 10.1016/j.resuscitation.2019.06.207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Savastano S, Baldi E, Chicote B, Aramendi E, Cacciatore E, Irusta U, Palo A, Iotti G, Visconti LO. Ventricular fibrillation amplitude spectral area and end-tidal carbon dioxide for shock success and ROSC prediction. Two sides of the same coin? Resuscitation 2019. [DOI: 10.1016/j.resuscitation.2019.06.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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21
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Salaberria R, Larrea A, Amas L, Alonso D, Etxeberria N, Egibar I, Mugica E, Totorika I, Lopez A, Huerta I, Gamboa E, Irusta U, Aramendi E. Cerebral oximetry vs capnography to monitor chest compressions and return of spontaneous circulation in out-of-hospital cardiac arrest. Resuscitation 2019. [DOI: 10.1016/j.resuscitation.2019.06.213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Jaureguibeitia X, Irusta U, Aramendi E, Alonso E, Owens P, Wang H, Idris A. Impedance Based Automatic Detection of Ventilations During Mechanical Cardiopulmonary Resuscitation. Annu Int Conf IEEE Eng Med Biol Soc 2019; 2019:19-23. [PMID: 31945835 DOI: 10.1109/embc.2019.8856822] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Monitoring ventilation rate is key to improve the quality of cardiopulmonary resuscitation (CPR) and increase the probability of survival in the event of an out-of-hospital cardiac arrest (OHCA). Ventilations produce discernible fluctuations in the thoracic impedance signal recorded by defibrillators. Impedance-based detection of ventilations during CPR is challenging due to chest compression artifacts. This study presents a method for an accurate detection of ventilations when chest compressions are delivered using a piston-driven mechanical device. Data from 223 OHCA patients were analyzed and 399 analysis segments totaling 3101 minutes of mechanical CPR were extracted. A total of 18327 ventilations were annotated using concurrent capnogram recordings. An adaptive least mean squares filter was used to remove compression artifacts. Potential ventilations were detected using a greedy peak detector, and the ventilation waveform was characterized using 8 waveform features. These features were used in a logistic regression classifier to discriminate true ventilations from false positives produced by the greedy peak detector. The classifier was trained and tested using patient wise 10-fold cross validation (CV), and 100 random CV partitions were created to statistically characterize the performance metrics. The peak detector presented a sensitivity (Se) of 99.30%, but a positive predictive value (PPV) of 54.43%. The best classifier configuration used 6 features and improved the mean (sd) Se and PPV of the detector to 93.20% (0.06) and 94.43% (0.04), respectively. When used to measure per minute ventilation rates for feedback to the rescuer, the mean (sd) absolute error in ventilation rate was 0.61 (1.64) min-1. The first impedance-based method to accurately detect ventilations and give feedback on ventilation rate during mechanical CPR has been demonstrated.
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23
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Picon A, Irusta U, Álvarez-Gila A, Aramendi E, Alonso-Atienza F, Figuera C, Ayala U, Garrote E, Wik L, Kramer-Johansen J, Eftestøl T. Mixed convolutional and long short-term memory network for the detection of lethal ventricular arrhythmia. PLoS One 2019; 14:e0216756. [PMID: 31107876 PMCID: PMC6527215 DOI: 10.1371/journal.pone.0216756] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 04/26/2019] [Indexed: 11/29/2022] Open
Abstract
Early defibrillation by an automated external defibrillator (AED) is key for the survival of out-of-hospital cardiac arrest (OHCA) patients. ECG feature extraction and machine learning have been successfully used to detect ventricular fibrillation (VF) in AED shock decision algorithms. Recently, deep learning architectures based on 1D Convolutional Neural Networks (CNN) have been proposed for this task. This study introduces a deep learning architecture based on 1D-CNN layers and a Long Short-Term Memory (LSTM) network for the detection of VF. Two datasets were used, one from public repositories of Holter recordings captured at the onset of the arrhythmia, and a second from OHCA patients obtained minutes after the onset of the arrest. Data was partitioned patient-wise into training (80%) to design the classifiers, and test (20%) to report the results. The proposed architecture was compared to 1D-CNN only deep learners, and to a classical approach based on VF-detection features and a support vector machine (SVM) classifier. The algorithms were evaluated in terms of balanced accuracy (BAC), the unweighted mean of the sensitivity (Se) and specificity (Sp). The BAC, Se, and Sp of the architecture for 4-s ECG segments was 99.3%, 99.7%, and 98.9% for the public data, and 98.0%, 99.2%, and 96.7% for OHCA data. The proposed architecture outperformed all other classifiers by at least 0.3-points in BAC in the public data, and by 2.2-points in the OHCA data. The architecture met the 95% Sp and 90% Se requirements of the American Heart Association in both datasets for segment lengths as short as 3-s. This is, to the best of our knowledge, the most accurate VF detection algorithm to date, especially on OHCA data, and it would enable an accurate shock no shock diagnosis in a very short time.
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Affiliation(s)
- Artzai Picon
- Computer Vision Group, Tecnalia Research & Innovation, Derio, Spain
| | - Unai Irusta
- Department of Communications Engineering, University of the Basque Country UPV/EHU, Bilbao, Spain
| | | | - Elisabete Aramendi
- Department of Communications Engineering, University of the Basque Country UPV/EHU, Bilbao, Spain
| | - Felipe Alonso-Atienza
- Department of Signal Theory and Communications, Rey Juan Carlos University, Madrid, Spain
- Client Solutions Advanced Analytics, BBVA, Madrid, Spain
| | - Carlos Figuera
- Department of Signal Theory and Communications, Rey Juan Carlos University, Madrid, Spain
- Client Solutions Advanced Analytics, BBVA, Madrid, Spain
| | - Unai Ayala
- Electronics and Computing Department, Mondragon Unibertsitatea, Faculty of Engineering (MU-ENG), Mondragón, Spain
| | | | - Lars Wik
- Norwegian National Advisory Unit on Prehospital Emergency Medicine (NAKOS), Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Jo Kramer-Johansen
- Norwegian National Advisory Unit on Prehospital Emergency Medicine (NAKOS), Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Trygve Eftestøl
- Department of Electrical Engineering and Computer Science, University of Stavanger, Stavanger, Norway
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Chicote B, Aramendi E, Irusta U, Owens P, Daya M, Idris A. Value of capnography to predict defibrillation success in out-of-hospital cardiac arrest. Resuscitation 2019; 138:74-81. [PMID: 30836170 PMCID: PMC6504568 DOI: 10.1016/j.resuscitation.2019.02.028] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 02/12/2019] [Accepted: 02/18/2019] [Indexed: 11/21/2022]
Abstract
BACKGROUND AND AIM Unsuccessful defibrillation shocks adversely affect survival from out-of-hospital cardiac arrest (OHCA). Ventricular fibrillation (VF) waveform analysis is the tool-of-choice for the non-invasive prediction of shock success, but surrogate markers of perfusion like end-tidal CO2 (EtCO2) could improve the prediction. The aim of this study was to evaluate EtCO2 as predictor of shock success, both individually and in combination with VF-waveform analysis. MATERIALS AND METHODS In total 514 shocks from 214 OHCA patients (75 first shocks) were analysed. For each shock three predictors of defibrillation success were automatically calculated from the device files: two VF-waveform features, amplitude spectrum area (AMSA) and fuzzy entropy (FuzzyEn), and the median EtCO2 (MEtCO2) in the minute before the shock. Sensitivity, specificity, receiver operating characteristic (ROC) curves and area under the curve (AUC) were calculated, for each predictor individually and for the combination of MEtCO2 and VF-waveform predictors. Separate analyses were done for first shocks and all shocks. RESULTS MEtCO2 in first shocks was significantly higher for successful than for unsuccessful shocks (31mmHg/25mmHg, p<0.05), but differences were not significant for all shocks (32mmHg/29mmHg, p>0.05). MEtCO2 predicted shock success with an AUC of 0.66 for first shocks, but was not a predictor for all shocks (AUC 0.54). AMSA and FuzzyEn presented AUCs of 0.76 and 0.77 for first shocks, and 0.75 and 0.75 for all shocks. For first shocks, adding MEtCO2 improved the AUC of AMSA and FuzzyEn to 0.79 and 0.83, respectively. CONCLUSIONS MEtCO2 predicted defibrillation success only for first shocks. Adding MEtCO2 to VF-waveform analysis in first shocks improved prediction of shock success. VF-waveform features and MEtCO2 were automatically calculated from the device files, so these methods could be introduced in current defibrillators adding only new software.
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Affiliation(s)
- Beatriz Chicote
- Communications Engineering Department, University of the Basque Country UPV/EHU, Ingeniero Torres Quevedo Plaza, 1, 48013 Bilbao, Spain.
| | - Elisabete Aramendi
- Communications Engineering Department, University of the Basque Country UPV/EHU, Ingeniero Torres Quevedo Plaza, 1, 48013 Bilbao, Spain
| | - Unai Irusta
- Communications Engineering Department, University of the Basque Country UPV/EHU, Ingeniero Torres Quevedo Plaza, 1, 48013 Bilbao, Spain
| | - Pamela Owens
- Department of Emergency Medicine, University of Texas Southwesterm Medical Center (UTSW), 5323 Harry Hines Blvd, Dallas, TX, USA
| | - Mohamud Daya
- Department of Emergency Medicine, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239-3098, USA
| | - Ahamed Idris
- Department of Emergency Medicine, University of Texas Southwesterm Medical Center (UTSW), 5323 Harry Hines Blvd, Dallas, TX, USA
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Elola A, Aramendi E, Irusta U, Alonso E, Lu Y, Chang MP, Owens P, Idris AH. Capnography: A support tool for the detection of return of spontaneous circulation in out-of-hospital cardiac arrest. Resuscitation 2019; 142:153-161. [PMID: 31005583 DOI: 10.1016/j.resuscitation.2019.03.048] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 02/27/2019] [Accepted: 03/18/2019] [Indexed: 11/19/2022]
Abstract
BACKGROUND Automated detection of return of spontaneous circulation (ROSC) is still an unsolved problem during cardiac arrest. Current guidelines recommend the use of capnography, but most automatic methods are based on the analysis of the ECG and thoracic impedance (TI) signals. This study analysed the added value of EtCO2 for discriminating pulsed (PR) and pulseless (PEA) rhythms and its potential to detect ROSC. MATERIALS AND METHODS A total of 426 out-of-hospital cardiac arrest cases, 117 with ROSC and 309 without ROSC, were analysed. First, EtCO2 values were compared for ROSC and no ROSC cases. Second, 5098 artefact free 3-s long segments were automatically extracted and labelled as PR (3639) or PEA (1459) using the instant of ROSC annotated by the clinician on scene as gold standard. Machine learning classifiers were designed using features obtained from the ECG, TI and the EtCO2 value. Third, the cases were retrospectively analysed using the classifier to discriminate cases with and without ROSC. RESULTS EtCO2 values increased significantly from 41 mmHg 3-min before ROSC to 57 mmHg 1-min after ROSC, and EtCO2 was significantly larger for PR than for PEA, 46 mmHg/20 mmHg (p < 0.05). Adding EtCO2 to the machine learning models increased their area under the curve (AUC) by over 2 percentage points. The combination of ECG, TI and EtCO2 had an AUC for the detection of pulse of 0.92. Finally, the retrospective analysis showed a sensitivity and specificity of 96.6% and 94.5% for the detection of ROSC and no-ROSC cases, respectively. CONCLUSION Adding EtCO2 improves the performance of automatic algorithms for pulse detection based on ECG and TI. These algorithms can be used to identify pulse on site, and to retrospectively identify cases with ROSC.
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Affiliation(s)
- Andoni Elola
- Communications Engineering Department, University of the Basque Country UPV/EHU, 48013 Bilbao, Spain.
| | - Elisabete Aramendi
- Communications Engineering Department, University of the Basque Country UPV/EHU, 48013 Bilbao, Spain
| | - Unai Irusta
- Communications Engineering Department, University of the Basque Country UPV/EHU, 48013 Bilbao, Spain
| | - Erik Alonso
- Communications Engineering Department, University of the Basque Country UPV/EHU, 48013 Bilbao, Spain
| | - Yuanzheng Lu
- Emergency and Disaster Medicine Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, China
| | - Mary P Chang
- Department of Emergency Medicine, University of Texas SouthWestern Medical Center (UTSW), Dallas, United States
| | - Pamela Owens
- Department of Emergency Medicine, University of Texas SouthWestern Medical Center (UTSW), Dallas, United States
| | - Ahamed H Idris
- Department of Emergency Medicine, University of Texas SouthWestern Medical Center (UTSW), Dallas, United States
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Nordseth T, Niles DE, Eftestøl T, Sutton RM, Irusta U, Abella BS, Berg RA, Nadkarni VM, Skogvoll E. Rhythm characteristics and patterns of change during cardiopulmonary resuscitation for in-hospital paediatric cardiac arrest. Resuscitation 2019; 135:45-50. [PMID: 30639791 DOI: 10.1016/j.resuscitation.2019.01.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 12/05/2018] [Accepted: 01/03/2019] [Indexed: 11/29/2022]
Abstract
During paediatric cardiopulmonary resuscitation (CPR), patients may transition between pulseless electrical activity (PEA), asystole, ventricular fibrillation/tachycardia (VF/VT), and return of spontaneous circulation (ROSC). The aim of this study was to quantify the dynamic characteristics of this process. METHODS ECG recordings were collected in patients who received CPR at the Children's Hospital of Philadelphia (CHOP) between 2006 and 2013. Transitions between PEA (including bradycardia with poor perfusion), VF/VT, asystole, and ROSC were quantified by applying a multi-state statistical model with competing risks, and by smoothing the Nelson-Aalen estimator of cumulative hazard. RESULTS Seventy-four episodes of cardiac arrest were included. Median age of patients was 15 years [IQR 11-17], 50% were female and 62% had a respiratory aetiology of arrest. Presenting cardiac arrest rhythms were PEA (60%), VF/VT (24%) and asystole (16%). A temporary surge of PEA was observed between 10 and 15 min due to a doubling of the transition rate from ROSC to PEA (i.e. 're-arrests'). The prevalence of sustained ROSC reached an asymptotic value of 30% at 20 min. Simulation suggests that doubling the transition rate from PEA to ROSC and halving the relapse rate might increase the prevalence of sustained ROSC to 50%. CONCLUSION Children and adolescents who received CPR were prone to re-arrest between 10 and 15 min after start of CPR efforts. If the rate of PEA to ROSC transition could be increased and the rate of re-arrests reduced, the overall survival rate may improve.
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Affiliation(s)
- Trond Nordseth
- Department of Emergency Medicine and Prehospital Services, St.Olav Hospital, Trondheim, Norway; Department of Circulation and Medical Imaging, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, NO-7491, Trondheim, Norway.
| | - Dana E Niles
- Department of Anesthesiology and Critical Care Medicine, The Children's Hospital of Philadelphia, Philadelphia, USA
| | - Trygve Eftestøl
- Department of Electrical Engineering and Computer Science, University of Stavanger, Stavanger, Norway
| | - Robert M Sutton
- Department of Anesthesiology and Critical Care Medicine, The Children's Hospital of Philadelphia, Philadelphia, USA
| | - Unai Irusta
- Department of Communications Engineering, University of the Basque Country, Bilbao, Spain
| | - Benjamin S Abella
- Center for Resuscitation Science, University of Pennsylvania, Philadelphia, USA
| | - Robert A Berg
- Department of Anesthesiology and Critical Care Medicine, The Children's Hospital of Philadelphia, Philadelphia, USA
| | - Vinay M Nadkarni
- Department of Anesthesiology and Critical Care Medicine, The Children's Hospital of Philadelphia, Philadelphia, USA
| | - Eirik Skogvoll
- Department of Circulation and Medical Imaging, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, NO-7491, Trondheim, Norway; Department of Anaesthesia and Intensive Care Medicine, St.Olav Hospital, Trondheim, Norway
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Aramendi E, Lu Y, Chang MP, Elola A, Irusta U, Owens P, Idris AH. A novel technique to assess the quality of ventilation during pre-hospital cardiopulmonary resuscitation. Resuscitation 2018; 132:41-46. [DOI: 10.1016/j.resuscitation.2018.08.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 07/19/2018] [Accepted: 08/13/2018] [Indexed: 10/28/2022]
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Isasi I, Irusta U, Elola A, Aramendi E, Ayala U, Alonso E, Kramer-Johansen J, Eftestol T. A Machine Learning Shock Decision Algorithm for Use During Piston-Driven Chest Compressions. IEEE Trans Biomed Eng 2018; 66:1752-1760. [PMID: 30387719 DOI: 10.1109/tbme.2018.2878910] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
GOAL Accurate shock decision methods during piston-driven cardiopulmonary resuscitation (CPR) would contribute to improve therapy and increase cardiac arrest survival rates. The best current methods are computationally demanding, and their accuracy could be improved. The objective of this work was to introduce a computationally efficient algorithm for shock decision during piston-driven CPR with increased accuracy. METHODS The study dataset contains 201 shockable and 844 nonshockable ECG segments from 230 cardiac arrest patients treated with the LUCAS-2 mechanical CPR device. Compression artifacts were removed using the state-of-the-art adaptive filters, and shock/no-shock discrimination features were extracted from the stationary wavelet transform analysis of the filtered ECG, and fed to a support vector machine (SVM) classifier. Quasi-stratified patient wise nested cross-validation was used for feature selection and SVM hyperparameter optimization. The procedure was repeated 50 times to statistically characterize the results. RESULTS Best results were obtained for a six-feature classifier with mean (standard deviation) sensitivity, specificity, and total accuracy of 97.5 (0.4), 98.2 (0.4), and 98.1 (0.3), respectively. The algorithm presented a five-fold reduction in computational demands when compared to the best available methods, while improving their balanced accuracy by 3 points. CONCLUSIONS The accuracy of the best available methods was improved while drastically reducing the computational demands. SIGNIFICANCE An efficient and accurate method for shock decisions during mechanical CPR is now available to improve therapy and contribute to increase cardiac arrest survival.
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Elola A, Aramendi E, Irusta U, Del Ser J, Alonso E, Daya M. ECG-based pulse detection during cardiac arrest using random forest classifier. Med Biol Eng Comput 2018; 57:453-462. [PMID: 30215212 DOI: 10.1007/s11517-018-1892-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Accepted: 08/29/2018] [Indexed: 10/28/2022]
Abstract
Sudden cardiac arrest is one of the leading causes of death in the industrialized world. Pulse detection is essential for the recognition of the arrest and the recognition of return of spontaneous circulation during therapy, and it is therefore crucial for the survival of the patient. This paper introduces the first method based exclusively on the ECG for the automatic detection of pulse during cardiopulmonary resuscitation. Random forest classifier is used to efficiently combine up to nine features from the time, frequency, slope, and regularity analysis of the ECG. Data from 191 cardiac arrest patients was used, and 1177 ECG segments were processed, 796 with pulse and 381 without pulse. A leave-one-patient out cross validation approach was used to train and test the algorithm. The statistical distributions of sensitivity (SE) and specificity (SP) for pulse detection were estimated using 500 patient-wise bootstrap partitions. The mean (std) SE/SP for nine-feature classifier was 88.4 (1.8) %/89.7 (1.4) %, respectively. The designed algorithm only requires 4-s-long ECG segments and could be integrated in any commercial automated external defibrillator. The method permits to detect the presence of pulse accurately, minimizing interruptions in cardiopulmonary resuscitation therapy, and could contribute to improve survival from cardiac arrest.
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Affiliation(s)
- Andoni Elola
- Communications Engineering Department, University of the Basque Country UPV/EHU, Alameda Urquijo S/N, 48013, Bilbao, Spain.
| | - Elisabete Aramendi
- Communications Engineering Department, University of the Basque Country UPV/EHU, Alameda Urquijo S/N, 48013, Bilbao, Spain
| | - Unai Irusta
- Communications Engineering Department, University of the Basque Country UPV/EHU, Alameda Urquijo S/N, 48013, Bilbao, Spain
| | - Javier Del Ser
- Communications Engineering Department, University of the Basque Country UPV/EHU, Alameda Urquijo S/N, 48013, Bilbao, Spain.,OPTIMA (Optimization, Modeling and Analytics) Research Area, TECNALIA, Parque Tecnologico, Edificio 700, 48160, Derio, Spain.,Data Science Group, Basque Center for Applied Mathematics (BCAM), Alameda de Mazarredo 14, 48009, Bilbao, Spain
| | - Erik Alonso
- Department of Applied Mathematics, University of the Basque Country UPV/EHU, Rafael Moreno "Pitxitxi", 3, 48013, Bilbao, Spain
| | - Mohamud Daya
- Department of Emergency Medicine, Oregon Health & Science University, Portland, OR, 97239-3098, USA
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Eftestøl T, Stokka SE, Kvaløy JT, Rad AB, Irusta U, Aramendi E, Alonso E, Nordseth T, Skogvoll E, Wik L, Kramer-Johansen J. A machine learning approach to model a probabilistic relationship between parameters reflecting quality of chest compressions and physiological response during out-of-hospital cardiopulmonary resuscitation. Resuscitation 2018. [DOI: 10.1016/j.resuscitation.2018.07.354] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Isasi I, Irusta U, Aramendi E, Olsen JÅ, Wik L. Removing mechanical chest compression artefacts induced by a load distributing band device from the ECG. Resuscitation 2018. [DOI: 10.1016/j.resuscitation.2018.07.069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Alonso E, Aramendi E, Irusta U, Daya M. A machine learning approach for detecting ventricular fibrillation during out-of-hospital cardiac arrest. Resuscitation 2018. [DOI: 10.1016/j.resuscitation.2018.07.096] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Larrea A, Salaberria R, Alonso D, Irusta U, Aramendi E, Isasi I, Lerma AM, García MJ, Férnandez C, Veliz D, Molina I. Monitoring chest compression rate using cerebral oximetry. Resuscitation 2018. [DOI: 10.1016/j.resuscitation.2018.07.241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Salaberria R, Larrea A, Alonso D, Aramendi E, Irusta U, Ortega JI, Fernandez-Barrera E, Virtus I, Arruebarrena JP, Ramos A. Evaluation of the increase in cerebral oximeter saturation during out-of-hospital mechanical chest compression sequences. Resuscitation 2018. [DOI: 10.1016/j.resuscitation.2018.07.220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Chicote B, Irusta U, Aramendi E, Alcaraz R, Rieta JJ, Isasi I, Alonso D, Baqueriza MDM, Ibarguren K. Fuzzy and Sample Entropies as Predictors of Patient Survival Using Short Ventricular Fibrillation Recordings during out of Hospital Cardiac Arrest. Entropy (Basel) 2018; 20:E591. [PMID: 33265680 PMCID: PMC7513119 DOI: 10.3390/e20080591] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 08/04/2018] [Accepted: 08/07/2018] [Indexed: 12/23/2022]
Abstract
Optimal defibrillation timing guided by ventricular fibrillation (VF) waveform analysis would contribute to improved survival of out-of-hospital cardiac arrest (OHCA) patients by minimizing myocardial damage caused by futile defibrillation shocks and minimizing interruptions to cardiopulmonary resuscitation. Recently, fuzzy entropy (FuzzyEn) tailored to jointly measure VF amplitude and regularity has been shown to be an efficient defibrillation success predictor. In this study, 734 shocks from 296 OHCA patients (50 survivors) were analyzed, and the embedding dimension (m) and matching tolerance (r) for FuzzyEn and sample entropy (SampEn) were adjusted to predict defibrillation success and patient survival. Entropies were significantly larger in successful shocks and in survivors, and when compared to the available methods, FuzzyEn presented the best prediction results, marginally outperforming SampEn. The sensitivity and specificity of FuzzyEn were 83.3% and 76.7% when predicting defibrillation success, and 83.7% and 73.5% for patient survival. Sensitivities and specificities were two points above those of the best available methods, and the prediction accuracy was kept even for VF intervals as short as 2s. These results suggest that FuzzyEn and SampEn may be promising tools for optimizing the defibrillation time and predicting patient survival in OHCA patients presenting VF.
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Affiliation(s)
- Beatriz Chicote
- Department of Communications Engineering, University of the Basque Country (UPV/EHU), 48013 Bilbao, Spain
| | - Unai Irusta
- Department of Communications Engineering, University of the Basque Country (UPV/EHU), 48013 Bilbao, Spain
| | - Elisabete Aramendi
- Department of Communications Engineering, University of the Basque Country (UPV/EHU), 48013 Bilbao, Spain
| | - Raúl Alcaraz
- Research Group in Electronic, Biomedical and Telecommunication Engineering, University of Castilla-La Mancha (UCLM), 16071 Cuenca, Spain
| | - José Joaquín Rieta
- BioMIT.org, Electronic Engineering Department, Universitat Politécnica de Valencia (UPV), 46022 Valencia, Spain
| | - Iraia Isasi
- Department of Communications Engineering, University of the Basque Country (UPV/EHU), 48013 Bilbao, Spain
| | - Daniel Alonso
- Emergency Medical System (Emergentziak-Osakidetza), Basque Health Service, 20014 Donostia, Spain
| | - María del Mar Baqueriza
- Emergency Medical System (Emergentziak-Osakidetza), Basque Health Service, 20014 Donostia, Spain
| | - Karlos Ibarguren
- Emergency Medical System (Emergentziak-Osakidetza), Basque Health Service, 20014 Donostia, Spain
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Isasi I, Irusta U, Aramendi E, Ayala U, Alonso E, Kramer-Johansen J, Eftestol T. A Multistage Algorithm for ECG Rhythm Analysis During Piston-Driven Mechanical Chest Compressions. IEEE Trans Biomed Eng 2018; 66:263-272. [PMID: 29993407 DOI: 10.1109/tbme.2018.2827304] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
GOAL An accurate rhythm analysis during cardiopulmonary resuscitation (CPR) would contribute to increase the survival from out-of-hospital cardiac arrest. Piston-driven mechanical compression devices are frequently used to deliver CPR. The objective of this paper was to design a method to accurately diagnose the rhythm during compressions delivered by a piston-driven device. METHODS Data was gathered from 230 out-of-hospital cardiac arrest patients treated with the LUCAS 2 mechanical CPR device. The dataset comprised 201 shockable and 844 nonshockable ECG segments, whereof 270 were asystole (AS) and 574 organized rhythm (OR). A multistage algorithm (MSA) was designed, which included two artifact filters based on a recursive least squares algorithm, a rhythm analysis algorithm from a commercial defibrillator, and an ECG-slope-based rhythm classifier. Data was partitioned randomly and patient-wise into training (60%) and test (40%) for optimization and validation, and statistically meaningful results were obtained repeating the process 500 times. RESULTS The mean (standard deviation) sensitivity (SE) for shockable rhythms, specificity (SP) for nonshockable rhythms, and the total accuracy of the MSA solution were: 91.7 (6.0), 98.1 (1.1), and 96.9 (0.9), respectively. The SP for AS and OR were 98.0 (1.7) and 98.1 (1.4), respectively. CONCLUSIONS The SE/SP were above the 90%/95% values recommended by the American Heart Association for shockable and nonshockable rhythms other than sinus rhythm, respectively. SIGNIFICANCE It is possible to accurately diagnose the rhythm during mechanical chest compressions and the results considerably improve those obtained by previous algorithms.
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Alonso E, Aramendi E, Irusta U, Daya M, Corcuera C, Lu Y, Idris AH. Evaluation of chest compression artefact removal based on rhythm assessments made by clinicians. Resuscitation 2018; 125:104-110. [DOI: 10.1016/j.resuscitation.2018.01.056] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 01/11/2018] [Accepted: 01/31/2018] [Indexed: 10/18/2022]
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Corcuera C, Galdos G, Olabarria M, Veintemillas J, Larrea A, Bastida JM, Ibarguren K, Alonso D, Chicote B, Aramendi E, Irusta U. Assessment of the diagnoses of automated external defibrillators operated by basic life support personnel. Resuscitation 2017. [DOI: 10.1016/j.resuscitation.2017.08.227] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Chicote B, Aramendi E, Irusta U, Alonso E, Elola A, Owens P, Idris A. Analysis of the end-tidal CO2 as shock outcome predictor in out-of-hospital cardiac arrest. Resuscitation 2017. [DOI: 10.1016/j.resuscitation.2017.08.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Galdos G, Olabarria M, Veintemillas J, Corcuera C, Bastida JM, Larrea A, Alonso D, Ibarguren K, Chicote B, Aramendi E, Irusta U. Challenges for clinicians in ECG based retrospective resuscitation rhythm annotation. Resuscitation 2017. [DOI: 10.1016/j.resuscitation.2017.08.121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Rad AB, Eftestol T, Engan K, Irusta U, Kvaloy JT, Kramer-Johansen J, Wik L, Katsaggelos AK. ECG-Based Classification of Resuscitation Cardiac Rhythms for Retrospective Data Analysis. IEEE Trans Biomed Eng 2017; 64:2411-2418. [PMID: 28371771 DOI: 10.1109/tbme.2017.2688380] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE There is a need to monitor the heart rhythm in resuscitation to improve treatment quality. Resuscitation rhythms are categorized into: ventricular tachycardia (VT), ventricular fibrillation (VF), pulseless electrical activity (PEA), asystole (AS), and pulse-generating rhythm (PR). Manual annotation of rhythms is time-consuming and infeasible for large datasets. Our objective was to develop ECG-based algorithms for the retrospective and automatic classification of resuscitation cardiac rhythms. METHODS The dataset consisted of 1631 3-s ECG segments with clinical rhythm annotations, obtained from 298 out-of-hospital cardiac arrest patients. In total, 47 wavelet- and time-domain-based features were computed from the ECG. Features were selected using a wrapper-based feature selection architecture. Classifiers based on Bayesian decision theory, k-nearest neighbor, k-local hyperplane distance nearest neighbor, artificial neural network (ANN), and ensemble of decision trees were studied. RESULTS The best results were obtained for ANN classifier with Bayesian regularization backpropagation training algorithm with 14 features, which forms the proposed algorithm. The overall accuracy for the proposed algorithm was 78.5%. The sensitivities (and positive-predictive-values) for AS, PEA, PR, VF, and VT were 88.7% (91.0%), 68.9% (70.4%), 65.9% (69.0%), 86.2% (83.8%), and 78.8% (72.9%), respectively. CONCLUSIONS The results demonstrate that it is possible to classify resuscitation cardiac rhythms automatically, but the accuracy for the organized rhythms (PEA and PR) is low. SIGNIFICANCE We have made an important step toward making classification of resuscitation rhythms more efficient in the sense of minimal feedback from human experts.
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Aramendi E, Elola A, Alonso E, Irusta U, Daya M, Russell JK, Hubner P, Sterz F. Feasibility of the capnogram to monitor ventilation rate during cardiopulmonary resuscitation. Resuscitation 2017; 110:162-168. [DOI: 10.1016/j.resuscitation.2016.08.033] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 07/27/2016] [Accepted: 08/09/2016] [Indexed: 10/21/2022]
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Figuera C, Irusta U, Morgado E, Aramendi E, Ayala U, Wik L, Kramer-Johansen J, Eftestøl T, Alonso-Atienza F. Machine Learning Techniques for the Detection of Shockable Rhythms in Automated External Defibrillators. PLoS One 2016; 11:e0159654. [PMID: 27441719 PMCID: PMC4956226 DOI: 10.1371/journal.pone.0159654] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 07/05/2016] [Indexed: 01/08/2023] Open
Abstract
Early recognition of ventricular fibrillation (VF) and electrical therapy are key for the survival of out-of-hospital cardiac arrest (OHCA) patients treated with automated external defibrillators (AED). AED algorithms for VF-detection are customarily assessed using Holter recordings from public electrocardiogram (ECG) databases, which may be different from the ECG seen during OHCA events. This study evaluates VF-detection using data from both OHCA patients and public Holter recordings. ECG-segments of 4-s and 8-s duration were analyzed. For each segment 30 features were computed and fed to state of the art machine learning (ML) algorithms. ML-algorithms with built-in feature selection capabilities were used to determine the optimal feature subsets for both databases. Patient-wise bootstrap techniques were used to evaluate algorithm performance in terms of sensitivity (Se), specificity (Sp) and balanced error rate (BER). Performance was significantly better for public data with a mean Se of 96.6%, Sp of 98.8% and BER 2.2% compared to a mean Se of 94.7%, Sp of 96.5% and BER 4.4% for OHCA data. OHCA data required two times more features than the data from public databases for an accurate detection (6 vs 3). No significant differences in performance were found for different segment lengths, the BER differences were below 0.5-points in all cases. Our results show that VF-detection is more challenging for OHCA data than for data from public databases, and that accurate VF-detection is possible with segments as short as 4-s.
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Affiliation(s)
- Carlos Figuera
- Department of Telecommunication Engineering, Universidad Rey Juan Carlos, Madrid, Spain
- * E-mail:
| | - Unai Irusta
- Department of Communication Engineering, University of the Basque Country UPV/EHU, Bilbao, Spain
| | - Eduardo Morgado
- Department of Telecommunication Engineering, Universidad Rey Juan Carlos, Madrid, Spain
| | - Elisabete Aramendi
- Department of Communication Engineering, University of the Basque Country UPV/EHU, Bilbao, Spain
| | - Unai Ayala
- Electronics and Computing Department, University of Mondragon, Mondragon, Spain
| | - Lars Wik
- Norwegian National Advisory Unit on Prehospital Emergency Medicine (NAKOS), Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Jo Kramer-Johansen
- Norwegian National Advisory Unit on Prehospital Emergency Medicine (NAKOS), Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Trygve Eftestøl
- Department of Electrical Engineering and Computer Science, University of Stavanger, Stavanger, Norway
| | - Felipe Alonso-Atienza
- Department of Telecommunication Engineering, Universidad Rey Juan Carlos, Madrid, Spain
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Rad AB, Engan K, Katsaggelos AK, Kvaløy JT, Wik L, Kramer-Johansen J, Irusta U, Eftestøl T. Automatic cardiac rhythm interpretation during resuscitation. Resuscitation 2016; 102:44-50. [DOI: 10.1016/j.resuscitation.2016.01.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Revised: 12/27/2015] [Accepted: 01/15/2016] [Indexed: 10/22/2022]
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Aramendi E, Irusta U. To interrupt, or not to interrupt chest compressions for ventilation: that is the question! J Thorac Dis 2016; 8:E121-3. [PMID: 26904239 PMCID: PMC4740154 DOI: 10.3978/j.issn.2072-1439.2016.01.04] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Elisabete Aramendi
- Communications Engineering Department, University of the Basque Country UPV/EHU, Alameda Urquijo S/N 48013 Bilbao, Spain
| | - Unai Irusta
- Communications Engineering Department, University of the Basque Country UPV/EHU, Alameda Urquijo S/N 48013 Bilbao, Spain
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Alonso E, Aramendi E, Daya M, Irusta U, Chicote B, Russell JK, Tereshchenko LG. Circulation detection using the electrocardiogram and the thoracic impedance acquired by defibrillation pads. Resuscitation 2015; 99:56-62. [PMID: 26705970 DOI: 10.1016/j.resuscitation.2015.11.014] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 10/06/2015] [Accepted: 11/22/2015] [Indexed: 11/25/2022]
Abstract
AIM To develop and evaluate a method to detect circulation in the presence of organized rhythms (ORs) during resuscitation using signals acquired by defibrillation pads. METHODS Segments containing electrocardiogram (ECG) and thoracic impedance (TI) signals free of artifacts were used. The ECG corresponded to ORs classified as pulseless electrical activity (PEA) or pulse-generating rhythm (PR). A first dataset containing 1091 segments was split into training and test sets to develop and validate the circulation detector. The method processed ECG and TI to obtain the impedance circulation component (ICC). Morphological features were extracted from ECG and ICC, and combined into a classifier to discriminate between PEA and PR. The performance of the method was evaluated in terms of sensitivity (PR) and specificity (PEA). A second dataset (86 segments from different patients) was used to assess two application of the method: confirmation of arrest by recognizing absence of circulation during ORs and detection of return of spontaneous circulation (ROSC) during resuscitation. In both cases, time to confirmation of arrest/ROSC was determined. RESULTS The method showed a sensitivity/specificity of 92.1%/90.3% and 92.2%/91.9% for training and test sets respectively. The method confirmed cardiac arrest with a specificity of 93.3% with a median delay of 0s after the first OR annotation. ROSC was detected with a sensitivity of 94.4% with a median delay of 57s from ROSC onset. CONCLUSION The method showed good performance, and can be reliably used to distinguish perfusing from non-perfusing ORs.
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Affiliation(s)
- Erik Alonso
- Communications Engineering Department, University of the Basque Country UPV/EHU, Alameda Urquijo S/N, 48013 Bilbao, Spain
| | - Elisabete Aramendi
- Communications Engineering Department, University of the Basque Country UPV/EHU, Alameda Urquijo S/N, 48013 Bilbao, Spain
| | - Mohamud Daya
- Department of Emergency Medicine, Oregon Health & Science University, 97239-3098 Portland, OR, United States
| | - Unai Irusta
- Communications Engineering Department, University of the Basque Country UPV/EHU, Alameda Urquijo S/N, 48013 Bilbao, Spain
| | - Beatriz Chicote
- Communications Engineering Department, University of the Basque Country UPV/EHU, Alameda Urquijo S/N, 48013 Bilbao, Spain
| | - James K Russell
- Department of Emergency Medicine, Oregon Health & Science University, 97239-3098 Portland, OR, United States
| | - Larisa G Tereshchenko
- Knight Cardiovascular Institute, Oregon Health & Science University, 97239-3098 Portland, OR, United States
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Alonso D, Vaqueriza I, Corcuera C, Vicente F, Aramendi E, Irusta U, Chicote B. Quality of chest compressions for EMT CPR in the Basque Autonomous Community. Resuscitation 2015. [DOI: 10.1016/j.resuscitation.2015.09.169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Ibarguren K, Unanue JM, Alonso D, Vaqueriza I, Irusta U, Aramendi E, Chicote B. Difference in survival from pre-hospital cardiac arrest between cities and villages in the Basque Autonomous Community. Resuscitation 2015. [DOI: 10.1016/j.resuscitation.2015.09.269] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Chicote B, Irusta U, Aramendi E, Bastida JM, Veintemillas J, Larrea A, Ibarguren K. Evolution of AMSA for shock success prediction during the pre-shock pause. Resuscitation 2015. [DOI: 10.1016/j.resuscitation.2015.09.049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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