Evaluation Of Hemodynamic Changes Of Two Therapeutic Regimens In Neonatal Respiratory Distress Syndrome By USCOM

Objective:To study the changes of hemodynamics in children with neonatal respiratory distress syndrome(NRDS)treated with nasal continuous positive airway pressure(nCPAP)with pulmonary surfactant(nCPAP+PS)and nCPAP by ultrasonic cardiac output monitor(USCOM).Partial pressure of carbon dioxide(PCO2)and oxygenation index(P/F)with PS supplementation was calculated to analyze its correlation with blood circulation.Methods:This was a prospective study.From May 2020 to January 2021,a total of 55 premature infants diagnosed with NRDS admitted to the Department of Neonatology,Affiliated Hospital of North Sichuan Medical College.They were divided into nCPAP+PS group(n=31)and nCPAP group(n=24).(1)In the nCPAP+PS group,hemodynamics were monitored 30 minutes before PS supplementation and 6 hours after PS supplementation,and PS was supplemented within 2-4 hours after birth.(2)In the nCPAP group,the hemodynamics were monitored within 30 minutes before the use of nCPAP.2 hours and 6 hours after nCPAP treatment the hemodynamics were monitored as well.Both groups were given nCPAP within 30 minutes after birth.USCOM was used for hemodynamic monitoring.The detection indexes included Flow time Corrected(FTc),Stroke Volume Variability(SVV),Cardiac Output Index(SVI),Cardiac Index(CI),Peripheral Vascular Resistance Index(SVRI),Smith Madigan Inotropy Index(SMII)and heart rate(HR).The changes were analyzed.(3)In the nCPAP+PS group,arterial partial pressure of carbon dioxide(PC02)was collected 30 minutes before the use of PS supplementation and 6 hours after PS supplementation,and oxygenation index(P/F)was calculated to analyze its correlation with blood circulation.Results:1.In the nCPAP+PS group:Before and after PS supplementation,FTc were 342.2±31.2(ms)and 357.8±35.7(ms),SVV were 18.4±6.0(%)and 22.1±6.7(%),SVI were 20.3±2.8(ml/m2)and 23.4±7.3(ml/m2),SVRI were 1030.4±256.3(dyne.sec.cm-5m2)and 1202.1±351.0(dyne.sec.cm-5m2)respectively,all the data were significantly increased.There was significant difference between the four groups of data(P<0.05).There was no significant difference in CI,SMII and HR before and after PS supplementation(P>0.05).2.nCPAP group:There was no statistical change in FTc,SVV,SVI,SVRI,CI,SMII and HR of NRDS children treated only by nCPAP(P>0.05).3.nCPAP+PS group:ΔPCO2 was positively correlated with ΔFTc and ΔSVV before and after PS supplementation in children with NRDS(r=0.360,r=0.379,P<0.05),but had no correlation withΔSVRI.There was no correlation between ΔP/F and ΔFTC,ΔSVV andΔSVRI.Conclusion:1.USCOM monitoring revealed that FTc,SVV,SVI and SVRI were significantly increased after treatment with nCPAP+PS,indicating that PS supplementation significantly improved the patients’ pre-and post-load,while SMII showed no significant change,indicating that PS supplementation had no effect on myocardial contractility.2.For premature infants treated with nCPAP only,their hemodynamic indexes did not change 30min before treatment,2h and 6h after treatment,which indicated that nCPAP treatment did not affect the hemodynamics of children.3.After nCPAP+PS treatment,ΔPCO2 was positively correlated with ΔFTc and ΔSVV,suggesting that PS may improve the ventilation blood flow ratio in children.