title: Visual evaluation of left ventricular performance predicts volume responsiveness early after resuscitation from cardiac arrest.
abstract: OBJECTIVE
  Haemodynamic optimisation is a fundamental goal of post-cardiac arrest therapy. Therefore, predicting volume responsiveness is a key issue in therapy of these high-risk patients and transoesophageal echocardiography (TEE) may provide helpful information. The aim of the present study was to evaluate the performance of visual evaluation (eyeballing) of standardised TEE-loops to predict volume responsiveness during post-cardiac arrest period.
  
  
  METHODS
  After approval of the local animal investigation committee, TEE mid-oesophageal long-axis views were recorded before a 5 ml/kg volume bolus at baseline and both 1 and 4h after return of spontaneous circulation (ROSC) from 8 min electrically induced cardiac arrest. Post-hoc, TEE loops were independently presented in randomized order to 7 blinded TEE-experts and 14 blinded TEE novices who were asked to predict whether the ventricle will increase stroke volume ≥ 15% after volume loading or not. Statistics were performed calculating sensitivity and specificity for the correct evaluation and agreement of raters.
  
  
  RESULTS
  14 out of 20 pigs were successfully resuscitated, and 924 ratings from 21 echocardiographers were included into analysis. Overall, we observed a sensitivity between 71 and 100%, whereas the specificity showed rather low values between 0 and 67% for prediction of volume responsiveness. Best prediction was recorded 1h after ROSC with median sensitivity (95% CI) of 100% (89-100%) and median specificity of 67% (61-72%). No significant difference was found between ratings of experienced and inexperienced echocardiographers. The concordance rate within the two groups was comparable.
  
  
  CONCLUSIONS
  In post-cardiac arrest period, visual evaluation of long-axis TEE loops allows prediction of volume responsiveness with good sensitivity and reasonable specificity even by novice users, and may therefore be suitable for implementation into treatment protocols.
authors.affiliation: Department of Anaesthesiology and Intensive Care Medicine, University Hospital Schleswig-Holstein, Campus Kiel, Schwanenweg 21, D-24119 Kiel, Germany. gruenewald@anaesthesie.uni-kiel.de
authors.forename: Matthias
authors.initials: M
authors.lastname: Gruenewald
authors.forename: Patrick
authors.initials: P
authors.lastname: Meybohm
authors.forename: Ole
authors.initials: O
authors.lastname: Broch
authors.forename: Amke
authors.initials: A
authors.lastname: Caliebe
authors.forename: Sebastian
authors.initials: S
authors.lastname: Koerner
authors.forename: Jochen
authors.initials: J
authors.lastname: Renner
authors.forename: Markus
authors.initials: M
authors.lastname: Steinfath
authors.forename: Berthold
authors.initials: B
authors.lastname: Bein
mesh_terms: D000818:Animals; D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D004195:Disease Models, Animal; D017548:Echocardiography, Transesophageal; D005260:Female; D005500:Follow-Up Studies; D006323:Heart Arrest / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008297:Male; D013318:Stroke Volume; D013552:Swine; D013997:Time Factors; D016896:Treatment Outcome; D016277:Ventricular Function, Left / Q000502:physiology*