A Brief Analysis of Equivalence Demonstration Techniques for Clinical Evaluation of Medical Devices / 中国医疗器械杂志

This study overviewed equivalence demonstration, the principles for the selection of comparative devices, the difficulties in equivalence demonstration, and the equivalence demonstration of special medical devices. In addition, the concept of equivalence demonstration was adopted for the products exempted from clinical evaluation, and there were many confusion in actual use. The operation points and difficult points of equivalence demonstration for the products exempted from clinical evaluation were introduced in order to provide reference for medical device colleagues.

The comparison of bladder neck descent and the hiatus area of levator ani between lithotomy position and separating-legs-holding-knees position / 中华超声影像学杂志

Objective:To investigate whether the bladder neck descent and the area of levator ani hiatus obtained on the maximum Valsalva were consistent at the lithotomy position and separating-legs-holding-knees position.Methods:Forty four subjects who underwent perineal pelvic floor four-dimensional ultrasound at 6-8 weeks postpartum in Third Hospital of Longgang Shenzhen from November 2019 to January 2020 were enrolled in this study. All subjects were able to effectively complete the maximum Valsalva maneuver both at the lithotomy position and the separating-legs-holding-knees position. The bladder neck descent and hiatus area of the levator Ani on the maximum Valsalva at these two positions were measured and compared.Results:The bladder neck descent at the separating-legs-holding-knees position was higher than that at the lithotomy position [(41.06±8.25)mm vs (39.96±8.10)mm; t=-2.965, P=0.005], and the hiatus area of levator Ani at the separating-legs-holding-knees position was larger than that at the lithotomy position[(27.55±4.90)cm 2 vs (26.32±4.76)cm 2; t=-3.820, P<0.001]. Conclusions:The bladder neck descent and the area of levator Ani hiatus on the maximum Valsalva at separating-legs- holding-knees position are larger than those on the maximum Valsalva at the lithotomy position.

Impact of hypertensive disorder complicating pregnancy on neonatal mortality and major complications in preterm infants / 中华实用儿科临床杂志

Objective@#To investigate the effect of hypertensive disorder complicating pregnancy (HDCP) on the mortality and early complications of premature infants.@*Methods@#The general clinical data of preterm infants with gestational age 24-36+ 6 weeks were collected from the cooperative units in the task group from January 1, 2013 to December 31, 2014.According to the severity of HDCP, the infants were divided into 4 groups: HDCP group, preeclampsia group, eclampsia group and non HDCP group, the mortality and major complications of preterm infants were compared, and the influencing factors were analyzed.@*Results@#The mortality rate of preterm in the HDCP group was significantly higher than that of non HDCP group, and there was statistical significance (χ2=9.970, P=0.019). Eclampsia had a highest fatality rate (4.8%) in the early stage, compared with non HDCP group (2.2%), and the difference was statistically significant.Comparison of HDCP group (1.8%) and eclampsia group (3.2%) suggested that there was no statistically significant difference.The incidence of respiratory distress syndrome (RDS) in preterm in HDCP group was significantly higher than that of non HDCP group, and there was statistical significance (χ2=13.241, P=0.004). Eclampsia group showed the highest incidence (35.4%), compared with non HDCP group (16.2%), the difference was statistically significant, but compared with HDCP group (19.9%), preeclampsia group (17.1%), there was no significant diffe-rence.The incidence of bronchopulmonary dysplasia (BPD) in preterm in HDCP group was significantly higher than that of non HDCP group (χ2=9.592, P=0.022), the highest incidence showed up in eclampsia group (9.7%), compared with non HDCP group (2.0%) and HDCP group (1.7%), the difference was statistically significant.But there was no statistically significant difference, compared with preeclampsia group.As the degree of HDCP aggravated, the incidence of BPD gradually rose.There was no significant impact on necrotizing enterocolitis (NEC), retinopathy of prematurity (ROP), intraventricular hemorrhage (IVH) and sepsis of HDCP (χ2=7.054, 7.214, 0.358, 3.852; P=0.070, 0.065, 0.949, 0.278). Considering the overall outcome of the child, that was, whether the child died or survived, he had at least one complication, and HDCP had an effect on it (χ2=15.697, P=0.001), so the incidence increased while the degree of HDCP rose gradually.After adjusting gestational age, birth weight, sex, way of delivery, placental abruption and front placenta, prenatal hormonal, gestational diabetes, neonatal asphyxia and other factors, the results displayed that HDCP was the factor leading to the death of premature baby (OR=2.159, 95%CI: 1.093-4.266), and comparison between preeclampsia and eclampsia showed no statistical difference (P=0.714, 0.389); HDCP had no significant influence on RDS, BDP, ICH, NEC, ROP and sepsis.@*Conclusions@#HDCP leads to increased risk of premature death, but also leads to the increased incidence of RDS and BPD, but it had no obvious effect on NEC, ROP, IVH, sepsis and other complications.