Effect Of Position On Ventilation And Gas Exchange Function In Neonate After Weaning From Mechanical Ventilation

Weaning from mechanical ventilation is the process of replacing mechanical ventilation to breathe independently , it depends on the successful spontaneously breathing of the patients and proper gas exchange. Breathing muscle fatigue, o-verloading, and other factors resulting to apnea and respiratory failure are important factors in the failure of the weaning from mechanical ventilation. In recent years, domestic and foreign scholars found prone position is useful for neonatal respiratory mechanics and can improve oxygenation. We therefore assume that the prone position may improve their ventilation and gas exchange functions at the same time it can not increase work of breathing , and reduce breathing muscle fatigue and breathing overloading and therefore the prone position may be better choice in neonate after weaning from machines. The aims of this study is to evaluate the effects of supine and prone position on ventilation and gas exchange functions in neonats in the initial six — hour period after weaning from mechanical ventilation.Patients and Methods1 Neonates within 28 day - age are treated in the NICU department of the 2nd affiliated hospital of China Medical University after weaning from mechanical ventilation, who are normal temperature.2 testing methods(1) Study infants are divided into prone group and supine group at random ( each group includes 30 infants) when they are weaning from mechanical ventilation. All of them inspire oxygen through head net, monitor TcSO2/RR any time and adjust oxygen flow rate continutly so as to keep TcSO2 in normal level. Record fraction of inspired oxygen ( FiO2) respiratory rate ( RR) after weaningfrom mechanical ventilation 15 minutes 1h 2h 3h 4h 5h 6h,measure arterial blood gas analysis after weaning from mechanical ventilation 1h 6h and record PaO2 arterial carbon dioxide tension (PaCO2) ,then calculate alveolar - arterial oxygen tension difference (A -aD02) respiratory index (RI) oxygenation index (PaO2/ FiO2 ) and so on.(2) Index;(T) ventilation and gas exchange function clinical monitoring indexes : FiO2, RR.(2) lungs ventilation and gas exchange function testing indexes: PaO2, PaC02.(3)intra - lung splitting stream and oxygenation indexes ( reflecting lung ailments) : A-aD02, PaO2/ FiO2, RI.3 Statistical analysisAll dates were expressed as (x ± s ). The independent samples t - test were carried out using the SPSS1O. 0 statistical software.ResultsIn that SP02 in the normal scope of the pilot testing of indexes showed that1. Ventilation function clinical monitoring indexes;(1) FiO2;At 15min after weaning from mechanical ventilation there is not statistical differences between supine and prone groups, lh ~ 6h after weaning from mechanical ventilation numerical value of FiO2 in supine group is significant lower than in the prone group and there is statistical discrepancy between of them.(2) RR : At 15min after weaning from mechanical ventilation, there is statistical discrepancy between the prone group and the supine group .At lh, 2h, 3h there is lower tendency in the prone group but there is not statistical discrepancy . At 4h, 5h, 6h numerical value of RR in prone group is lower than in supine group and there is statistical discrepancy between of them.2. Ventilation and gas exchange function testing indexes;(1) PaO2 :at lh and 6h after weaning from mechanical ventilation prone position are clearly higher than the supine position group and there is a statistical discrepancy.(2) PaCO2 : at lh after weaning from mechanical ventilation there is not differences between of them. At 6h prone position are clearly higher than the supine position group and there is a statistical discrepancy3. intra - lung spliting stream and oxygenation indexes : A -aD02N PaO2/ FiO2NRI;at lh and 6h after weaning from mechanical ventilation there is statistical discrepancy. The value of A -aD02^RI in supine group is higher than prone group. The value of PaO2/ FiO2 in supine group is lower than in prone group.ConclusionAt first 6h after weaning from mechanical prone position can improve ventilation and gas exchange functions in low concentrations of oxygen inhalation and still keep oxygenation superior to supine position.