title: [Study of setting of ventilator volume tidal and airway pressure alarm threshold with continuous extra-sternum heart compression in cardiopulmonary resuscitation].
abstract: OBJECTIVE
  To investigate the setting of ventilator volume tidal (VT) and airway pressure alarm threshold during cardiopulmonary resuscitation (CPR) by continuous extra-sternum heart compression.
  
  
  METHODS
  Forty cases with respiration and cardiac arrest in the department of critical care medicine were randomly divided into low VT ventilation group and conventional VT group. Both groups were given the volume control mode. In the low VT ventilation group, VT was set on 6 - 7 ml/kg, and high pressure alarm threshold was adjusted to 60 cm H2O by the conventional 40 cm H2O during CPR. In the conventional VT group, VT and high pressure alarm threshold were set at 8 - 12 ml/kg and 40 cm H2O, respectively. Real-time actual VT, peak inspiratory pressure (PIP), and arterial blood gas test, blood lactic acid at 10 minutes and 30 minutes after CPR were observed.
  
  
  RESULTS
  At 10 minutes after CPR, in the low VT ventilation group, arterial blood pH, arterial partial pressure of oxygen (PaO2), arterial partial pressure of carbon dioxide (PaCO2), HCO3(-), arterial oxygen saturation (SaO2) and blood lactic acid were better as compared with those in the conventional VT ventilation group (pH: 7.21±0.09 vs. 7.13±0.07, PaO2: 45.35±5.92 mm Hg vs. 40.70±4.70 mm Hg, PaCO2: 57.10±7.59 mm Hg vs. 61.60±5.47 mm Hg, HCO3(-): 18.50±3.50 mmol/L vs. 14.75±2.65 mmol/L, SaO2: 0.796±0.069 vs. 0.699±0.066, blood lactic acid: 7.07±1.60 mmol/L vs. 8.13±1.56 mmol/L, all P<0.05). The success rate of resuscitation in the low VT ventilation group was higher than that of the conventional VT ventilation group (45% vs. 15%, P<0.05), and PIP (cm H2O) of low VT ventilation group was lower than that of the conventional VT group (37.25±7.99 cm H2O vs. 42.70±7.40 cm H2O, P<0.05). In all the patients in both groups barotrauma did not occur.
  
  
  CONCLUSIONS
  The strategy of low ventilator VT (6 - 7 ml/kg) with appropriate elevation of airway pressure alarm threshold was better than that of conventional ventilation setting, with no increase in incidence of barotraumas during CPR.
authors: Department of Intensive Care Unit, the People's Hospital of Liuzhou, Liuzhou, Guangxi, China.
authors: Jian-yu
authors: JY
authors: Luo
authors: Xiao-yuan
authors: XY
authors: Wang
authors: Tian-bin
authors: TB
authors: Cai
authors: Wen-fang
authors: WF
authors: Jiang
mesh_terms: D001784:Blood Gas Analysis; D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D004867:Equipment Design; D006323:Heart Arrest / Q000628:therapy*; D006336:Heart Massage / Q000379:methods; D006801:Humans; D011312:Pressure; D012121:Respiration, Artificial / Q000295:instrumentation / Q000379:methods*; D013249:Sternum / Q000502:physiology*; D013990:Tidal Volume