title: Combining Amplitude Spectrum Area with Previous Shock Information Using Neural Networks Improves Prediction Performance of Defibrillation Outcome for Subsequent Shocks in Out-Of-Hospital Cardiac Arrest Patients.
abstract: OBJECTIVE
  Quantitative ventricular fibrillation (VF) waveform analysis is a potentially powerful tool to optimize defibrillation. However, whether combining VF features with additional attributes that related to the previous shock could enhance the prediction performance for subsequent shocks is still uncertain.
  
  
  METHODS
  A total of 528 defibrillation shocks from 199 patients experienced out-of-hospital cardiac arrest were analyzed in this study. VF waveform was quantified using amplitude spectrum area (AMSA) from defibrillator's ECG recordings prior to each shock. Combinations of AMSA with previous shock index (PSI) or/and change of AMSA (ΔAMSA) between successive shocks were exercised through a training dataset including 255shocks from 99patientswith neural networks. Performance of the combination methods were compared with AMSA based single feature prediction by area under receiver operating characteristic curve(AUC), sensitivity, positive predictive value (PPV), negative predictive value (NPV) and prediction accuracy (PA) through a validation dataset that was consisted of 273 shocks from 100patients.
  
  
  RESULTS
  A total of61 (61.0%) patients required subsequent shocks (N = 173) in the validation dataset. Combining AMSA with PSI and ΔAMSA obtained highest AUC (0.904 vs. 0.819, p<0.001) among different combination approaches for subsequent shocks. Sensitivity (76.5% vs. 35.3%, p<0.001), NPV (90.2% vs. 76.9%, p = 0.007) and PA (86.1% vs. 74.0%, p = 0.005)were greatly improved compared with AMSA based single feature prediction with a threshold of 90% specificity.
  
  
  CONCLUSIONS
  In this retrospective study, combining AMSA with previous shock information using neural networks greatly improves prediction performance of defibrillation outcome for subsequent shocks.
authors: School of Biomedical Engineering, Third Military Medical University, Chongqing 400038, China.
authors: Mi
authors: M
authors: He
authors: Emergency Department, Xinqiao Hospital, Third Military Medical University, Chongqing 400038, China.
authors: Yubao
authors: Y
authors: Lu
authors: Emergency Department, Southwest Hospital, Third Military Medical University, Chongqing 400038, China.
authors: Lei
authors: L
authors: Zhang
authors: Department of Medical Engineering, Daping Hospital & Research Institute of Surgery, Third Military Medical University, Chongqing 400042, China.
authors: Hehua
authors: H
authors: Zhang
authors: School of Biomedical Engineering, Third Military Medical University, Chongqing 400038, China.
authors: Yushun
authors: Y
authors: Gong
authors: School of Biomedical Engineering, Third Military Medical University, Chongqing 400038, China.
authors: Yongqin
authors: Y
authors: Li
mesh_terms: D019540:Area Under Curve; D047548:Defibrillators; D004554:Electric Countershock / Q000379:methods*; D004562:Electrocardiography; D006801:Humans; D016571:Neural Networks, Computer; D058687:Out-of-Hospital Cardiac Arrest / Q000628:therapy*; D011237:Predictive Value of Tests; D012372:ROC Curve; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted; D012984:Software; D016896:Treatment Outcome; D014693:Ventricular Fibrillation / Q000628:therapy*