Clinic Research On Effects Of Different Doses Of Caffeine On Early Pulmonary Function And Complications In Premature Infants

Objectives:To treat premature infants with different maintenance doses of caffeine citrate after birth based on the method of randomized controlled study,and to observe the differences between the two groups in terms of pulmonary function(PF)at 7 days,14 days and 40 weeks after birth,apnea of prematurity(AOP),noninvasive ventilation time,oxygen uptake time,adverse drug reactions,complications,etc.,so as to provide some reference for the optimal dosage of caffeine citrate in combination with the early dynamic changes of pulmonary function.Methods:120 premature infants born in the Affiliated Hospital of Qingdao University from April 2019 to January 2022 with gestational age of 28 weeks to 33+6 weeks,who did not need invasive mechanical ventilation after birth,were selected as the research object.Within 2 hours of admission,5 cases of severe asphyxia were excluded,3 cases of mothers had a history of smoking,4 cases of first-degree relatives had a history of asthma,and the remaining premature infants were randomly divided into high maintenance dose group and low maintenance dose group of caffeine.Two groups of premature infants were given caffeine citrate 20mg/(kg d)at the beginning,and 24 hours later,the high and low maintenance dose groups were given 10mg/(kg d)and 5mg/(kg d)respectively to prevent and treat neonatal apnea.During the study,6 cases of severe infection,3 cases of severe intracranial hemorrhage,2 cases of complex congenital heart disease,2 cases of respiratory tract malformation and 2 cases of methylmalonic acidemia were excluded.One case of khitrin’s protein deficiency,10 premature infants who couldn’t get off the ventilator 7 days after birth,2 died,and 2 lost to follow-up.In the study,78 premature infants who completed lung function test at 7 days,14 days,and 40 weeks,including high maintenance dose group(40 cases)and low maintenance dose group(38 cases),including40 cases in high maintenance dose group and 38 cases in low maintenance dose group.In addition,39 healthy full-term infants with gestational age of 39-40 weeks were included as the control group,and the pulmonary function of the healthy full-term infants in the control group was tested on the second day after birth.Two groups of premature infants and term infants were tested by Tidal pulmonary function tests,premature infants completed lung function testing after 3h of caffeine application.When premature infants were tested without oxygen therapy or During noninvasive ventilation,the breathing was stable within 10-15 minutes after weaning from the ventilator under the condition of inspired oxygen concentration of 21%.The perinatal period data of premature infants were collected,including gender,gestational age,birth length,birth weight,delivery mode,number of cases with enough course of dexamethasone during maternal pregnancy,number of cases with premature rupture of membranes ≥ 18 h,The number of cases of PS(pulmonary surfactant,PS)application,the dosage of PS application,Apgar score at 1minute and 5 minutes after birth.Test indicators during treatment were recorded,including related parameters of the tidal breath pulmonary function of premature infants and term infants in the two groups,the number of premature infants with apnea,non-invasive ventilation time,oxygen uptake time,and the number of possible complications.Finally,the pulmonary function parameters of premature the differences of pulmonary function parameters between the high maintenance dose group and the low maintenance dose group were compared at 7 days,14 days and 40 weeks of corrected gestational age after birth;the differences of pulmonary function between premature infants in high and low maintenance dose groups at 40 weeks of corrected gestational age and healthy term infants were compared;the differences of apnea frequency,noninvasive auxiliary ventilation time,oxygen uptake time and possible complications between high and low maintenance dose groups were compared.Results:1.The tidal volume peak kilogram(TV/kg),TPTEF/TE,VPTEF/VE of premature infants in the high maintenance dose group were higher than those in the low maintenance dose group,and the difference was statistically significant(P<0.05);the respiratory rate(RR)of the high maintenance dose group was higher than that of the low maintenance dose group at 7 and 14 days after birth,and the difference was statistically significant(P<0.05).2.Comparison of pulmonary function between two groups of premature infants at40 weeks of corrected gestational age and healthy term infants at 2 days of birth: the premature infants in the high and low maintenance dose groups had lower VT/kg,TPEF/t E,VPEF/VE,expiratory flow when exhaling 75% tidal volume(TEF25),expiratory flow when exhaling 50% tidal volume(TEF50,expiratory flow when exhaling25% tidal volume(TEF75)than that of the healthy term infants,and the difference was statistically significant(P<0.05);the premature infants in the high and low maintenance dose groups had higher respiratory rate(RR)and the inspiration and expiration ratio(Ti/Te)than that of the healthy term infants,and the difference was statistically significant(P<0.05).3.The high maintenance dose group could more effectively reduce the number of apnea and oxygen inhalation time than the low maintenance dose group,and the difference was statistically significant(P<0.05);there was no significant difference in the non-invasive ventilation time(P > 0.05).4.The difference between the high and low caffeine maintenance dose groups in the comparison of related complications such as NEC,feeding intolerance,hyperglycemia,tachycardia,retinopathy of predictability(ROP),intravascular hypertension(IVH)had no statistical significance(P>0.05).Conclusions1 The high caffeine maintenance dose group can better improve the early pulmonary function of premature infants than the low caffeine maintenance dose group.2 The pulmonary function of premature infants in high and low caffeine maintenance dose groups at 40 weeks of corrected gestational age was significantly lower than that of healthy term infants.3 The high caffeine maintenance dose group can reduce the frequency and the oxygen uptake time compared with the low caffeine maintenance dose group.4 There was no significant statistical difference between the high maintenance dose group and the low maintenance dose group in the common complications after the use of caffeine.