기관 삽관후 인공호흡기를 적용한 개심술 환아의 인공기도 체외 용적이 폐환기 미치는 영향 = The Effects of Artificial Dead Space on the Pulmonary Ventilation of Intubated Children with Mechanical Ventilation

다국어 초록 (Multilingual Abstract)

This study was done to evaluate the effect reducing artificial dead space on intubated children.
Data were collected from July 1st, 1998 to August 31st, 1999. The subjects were selected from a pediatric intensive care unit of 'S' hospital and intubated with 3.5 mm or 4.5 mm endotracheal tube after open heart surgery. They were composed of 34 patients : 17 patients were assigned to the experimental group and the rest of them were placed in the control group.
The artificial airway volume was minimized in the experimental group, and the control group maintained the artificial airway volume. ETCO₂, PaCO₂, SPO₂ were measured as indicators of pulmonary ventilation.
The tools of this study were GEM-Premier^Ⓡ and Space-Lab^Ⓡ patient monitors.
The data were analyzed using the SPSS/PC⁺ program. The Χ²-test was used to find general characteristics. The t-test was used to test the homogenety of the pulmonary ventilation status and mechanical ventilation setting before intervention between the two groups. Also, the paired t-test was used to examine the hypothesis.
The results can be summerized as :
1. CO₂ can be expelled effectively from the body in case artificial dead space was decreased.
2. As the artificial dead space was reduced, the difference between E_TCO₂ and PaCO₂ was decreased, in other words pulmonary ventilation was improved.
3. If the artificial dead space occupied above 15 percent of tidal volume, the effect of CO₂ was retention revealed in the body.
4. If the artificial dead space occupied below 1.5 percent of tidal volume, there was no dead space effect.
Based on the results, the following is suggested to be applied practically :
1. A kind of the ventilator circuit acting artificial dead space should be removed from the intubated children with mechanical ventilaion.
2. The endotracheal tube should not be cut because extra-body space of the endotracheal tube did not have an effect on the dead space of the intubated children.
Since the researcher could not cover this aspect in the study, they recommend the following.
1. The study should be extended to the other pulmonary disease patients for the effect of improving pulmonary ventilation.
2. Also, further studying with a more narrow interval in the extra-body space of the artificial airway will be able to explain the point of artificial dead space with proper ventilation.