ABSTRACT
BACKGROUND: We conducted this study to verify whether a mechanical ventilator is adequate for cardiopulmonary resuscitation (CPR). METHODS: A self-inflating bag resuscitator and a mechanical ventilator were used to test two experimental models: Model 1 (CPR manikin without chest compression) and Model 2 (CPR manikin with chest compression). Model 2 was divided into three subgroups according to ventilator pressure limits (P(limit)). The self-inflating bag resuscitator was set with a ventilation rate of 10 breaths/min with the volume-marked bag-valve procedure. The mode of the mechanical ventilator was set as follows: volume-controlled mandatory ventilation of tidal volume (Vt) 600 mL, an inspiration time of 1.2 seconds, a constant flow pattern, a ventilation rate of 10 breaths/minute, a positive end expiratory pressure of 3 cmH2O and a maximum trigger limit. Peak airway pressure (P(peak)) and Vt were measured by a flow analyzer. Ventilation adequacy was determined at a Vt range of 400-600 mL with a P(peak) of < or = 50 cmH2O. RESULTS: In Model 1, Vt and P(peak) were in the appropriate range in the ventilation equipments. In Model 2, for the self-inflating bag resuscitator, the adequate Vt and P(peak) levels were 17%, and the P(peak) adequacy was 20% and the Vt was 65%. For the mechanical ventilator, the adequate Vt and P(peak) levels were 85%; the P(peak) adequacy was 85%; and the Vt adequacy was 100% at 60 cmH2O of P(limit). CONCLUSIONS: In a manikin model, a mechanical ventilator was superior to self-inflating bag resuscitator for maintaining adequate ventilation during chest compression.
Subject(s)
Cardiopulmonary Resuscitation , Manikins , Models, Theoretical , Positive-Pressure Respiration , Thorax , Tidal Volume , Ventilation , Ventilators, MechanicalABSTRACT
BACKGROUND: We conducted this study to verify whether a mechanical ventilator is adequate for cardiopulmonary resuscitation (CPR). METHODS: A self-inflating bag resuscitator and a mechanical ventilator were used to test two experimental models: Model 1 (CPR manikin without chest compression) and Model 2 (CPR manikin with chest compression). Model 2 was divided into three subgroups according to ventilator pressure limits (P(limit)). The self-inflating bag resuscitator was set with a ventilation rate of 10 breaths/min with the volume-marked bag-valve procedure. The mode of the mechanical ventilator was set as follows: volume-controlled mandatory ventilation of tidal volume (Vt) 600 mL, an inspiration time of 1.2 seconds, a constant flow pattern, a ventilation rate of 10 breaths/minute, a positive end expiratory pressure of 3 cmH2O and a maximum trigger limit. Peak airway pressure (P(peak)) and Vt were measured by a flow analyzer. Ventilation adequacy was determined at a Vt range of 400-600 mL with a P(peak) of < or = 50 cmH2O. RESULTS: In Model 1, Vt and P(peak) were in the appropriate range in the ventilation equipments. In Model 2, for the self-inflating bag resuscitator, the adequate Vt and P(peak) levels were 17%, and the P(peak) adequacy was 20% and the Vt was 65%. For the mechanical ventilator, the adequate Vt and P(peak) levels were 85%; the P(peak) adequacy was 85%; and the Vt adequacy was 100% at 60 cmH2O of P(limit). CONCLUSIONS: In a manikin model, a mechanical ventilator was superior to self-inflating bag resuscitator for maintaining adequate ventilation during chest compression.
Subject(s)
Cardiopulmonary Resuscitation , Manikins , Models, Theoretical , Positive-Pressure Respiration , Thorax , Tidal Volume , Ventilation , Ventilators, MechanicalABSTRACT
Pressure-limit ventilators are used because it is believed that they decrease the incidence of pulmonary gas leaks and chronic lung disease. The disadvantage of pressurelimit ventilators is that there is no automatic compensation for changes in compliance and resistance of the lung and the chest wall. Consequently, if lung compliance decreases, tidal volume will decrease and blood gases will worsen. The aim of this study is to find the adequacy for the oxygenation and ventilation of volume-limit ventilator with pressure-limit control accessary in pediatric patient with congenital heart disease. The pressure-limit control accessary for anesthetic ventilator(AV-E, North America Drager, Bedford, USA) in 36 pediatric patients undertaken open heart surgery and thoracotomy, retrospectively, were employed. The patients were divided into 3 groups according to their body weights. The respiratory rate of group I ( or = 5, or = 10, < 20 kg, n=8) was 15/min. The patients were divided into another 2 groups, A(n=30) or B(n=6), with the supine or lateral, respectively according to the operation position. The results showed all the values of arterial blood gases almost within normal limits, except one patient in each group. We concluded that anesthetic Drager infant ventilator with pressure-limit control accessary was useful during controlled ventilation, and this is suitable for the prolonged operation in pediatric patients with the supine or lateral position.