title: Hemodynamic improvement of a LUCAS 2 automated device by addition of an impedance threshold device in a pig model of cardiac arrest.
abstract: BACKGROUND
  The combination of the LUCAS 2 (L-CPR) automated CPR device and an impedance threshold device (ITD) has been widely implemented in the clinical field. This animal study tested the hypothesis that the addition of an ITD on L-CPR would enhance cerebral and coronary perfusion pressures.
  
  
  METHODS
  Ten female pigs (39.0 ± 2.0 kg) were sedated, intubated, anesthetized with isofluorane, and paralyzed with succinylcholine (93.3 μg/kg/min) to inhibit the potential confounding effect of gasping. After 4 min of untreated ventricular fibrillation, 4 min of L-CPR+an active ITD or L-CPR+a sham ITD was initiated and followed by another 4 min of the alternative method of CPR. Systolic blood pressure (SBP), diastolic blood pressure (DBP), diastolic right atrial pressure (RAP), intracranial pressure (ICP), airway pressure, and end tidal CO2 (ETCO2) were recorded continuously. Data expressed as mean mmHg ± SD.
  
  
  RESULTS
  Decompression phase airway pressure was significantly lower with L-CPR+active ITD versus L-CPR+sham ITD (-5.3 ± 2.2 vs. -0.5 ± 0.6; p<0.001). L-CPR+active ITD treatment resulted in significantly improved hemodynamics versus L-CPR+sham ITD: ETCO2, 35 ± 6 vs. 29 ± 7 (p=0.015); SBP, 99 ± 9 vs. 93 ± 15 (p=0.050); DBP, 24 ± 12 vs. 19 ± 15 (p=0.006); coronary perfusion pressure, 29 ± 8 vs. 26 ± 7 (p=0.004) and cerebral perfusion pressure, 24 ± 13 vs. 21 ± 12 (p=0.028).
  
  
  CONCLUSIONS
  In pigs undergoing L-CPR the addition of the active ITD significantly reduced intrathoracic pressure and increased vital organ perfusion pressures.
authors.affiliation: Department of Medicine-Cardiovascular Division, University of Minnesota, Minneapolis, MN, United States; UJF-Grenoble 1/CNRS/CHU de Grenoble/TIMC-IMAG UMR 5525, Grenoble, France.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Debaty
authors.affiliation: AP-HP, Hôpital Lariboisière, Services des Urgences, Univ Paris Diderot, Sorbonne Paris Cité, UMRS 942, F-75018 Paris, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Segal
authors.affiliation: Department of Integrated Biology & Physiology, Medical School, University of Minnesota, Minneapolis, MN, United States.
authors.forename: Tim
authors.initials: T
authors.lastname: Matsuura
authors.affiliation: Department of Medicine-Cardiovascular Division, University of Minnesota, Minneapolis, MN, United States.
authors.forename: Brian
authors.initials: B
authors.lastname: Fahey
authors.affiliation: Whatcom County Emergency Medical Services, Department of Emergency Medicine, PeaceHealth St. Joseph Medical Center, Bellingham, WA, United States.
authors.forename: Marvin
authors.initials: M
authors.lastname: Wayne
authors.affiliation: Department of Emergency Medicine, Hennepin County Medical Center, Minneapolis, MN, United States.
authors.forename: Brian
authors.initials: B
authors.lastname: Mahoney
authors.affiliation: Department of Emergency Medicine, Regions Hospital, St. Paul, MN, United States.
authors.forename: Ralph
authors.initials: R
authors.lastname: Frascone
authors.affiliation: Allina Health Emergency Medical Services, St. Paul, MN, United States.
authors.forename: Charles
authors.initials: C
authors.lastname: Lick
authors.affiliation: Department of Medicine-Cardiovascular Division, University of Minnesota, Minneapolis, MN, United States. Electronic address: yanno001@umn.edu.
authors.forename: Demetris
authors.initials: D
authors.lastname: Yannopoulos
mesh_terms: D000818:Animals; D016887:Cardiopulmonary Resuscitation / Q000295:instrumentation*; D004195:Disease Models, Animal; D017097:Electric Impedance; D004867:Equipment Design; D005260:Female; D006323:Heart Arrest / Q000209:etiology / Q000628:therapy*; D006439:Hemodynamics; D013552:Swine; D014693:Ventricular Fibrillation / Q000150:complications* / Q000503:physiopathology
keywords: Cardiac arrest; Cardiopulmonary resuscitation (CPR); Impedance threshold device; Mechanical CPR