早期或晚期抢救性给予肺表面活性物质对呼吸窘迫综合征早产儿的影响

目的 观察早期或晚期抢救性给予肺表面活性物质(PS)对呼吸窘迫综合征(RDS)早产儿的影响.方法 回顾性分析99例需要机械通气的RDS患儿的临床资料.按照PS的给予时间分为早期组(出生2 h内)48例和晚期组(出生2～12 h)51例,观察2组在机械通气时间、氧疗时间、病死率以及并发症:气漏(肺间质气肿、气胸)、肺出血、支气管肺发育不良(BPD)、坏死性小肠结肠炎(NEC)、PDA、严重脑室内出血(IVH)的发生率方面的变化.结果 早期组和晚期组机械通气时间[(4.14±1.88) d vs (5.84±3.36) d]比较有统计学差异(P＜0.05).2组氧疗时间[(5.84±3.36) d vs (8.05±5.48) d]比较差异有统计学意义(P＜0.05).28 d内早产儿的病死率:早期组为6.25%、晚期组为5.88%,出生12 h内不同时间给予PS对病死率无影响(OR=1.07,95% CI 0.21～5.56,P=1.00).早期组BPD的发生率8.7%,低于晚期组16.0%,但无统计学差异(OR=0.49,95%CI 0.13～1.74,P=0.36).其他并发症如气漏、肺出血、PDA、NEC、严重IVH发生率,2组患儿之间均无明显差异(Pa＞0.05).结论 早期抢救性给予PS能显著减少RDS早产儿的机械通气时间和氧疗时间,降低BPD的发生率.     

机械通气早产儿支气管肺发育不良的高危因素分析

目的 探讨机械通气早产儿支气管肺发育不良(bronchopulmonary dysplasia,BPD)的发病率及高危因素.方法 回顾性分析2008年1月至2009年12月我院NICU住院治疗并存活28d以上的、胎龄≤32周的极低出生体质量儿196例的临床资料,其中机械通气治疗61例,21例诊断为BPD(BPD组),40例为非BPD组,对两组患儿临床资料进行对照研究.结果 胎龄≤32周的极低出生体质量儿的BPD总发病率为10.7%,有机械通气史者发病率高达34.4%;BPD组患儿的胎龄及出生体质量均较非BPD组低.BPD组有胎膜早破史及合并新生儿呼吸窘迫综合征(neonatal respiratory distress syndrome,NRDS)、产后感染、应用静脉营养时间长者较非BPD组均明显增高,差异有统计学意义(P<0.05);性别、窒息史、肺表面活性物质的应用、呼气末正压、平均气道压力两组比较差异无统计学意义(P>0.05),而吸气峰压、机械通气最高氧浓度、机械通气时间及总吸氧时间在两组间差异有统计学意义(P<0.05);合并NRDS、产后感染、机械通气时间、机械通气最高氧浓度为发生BPD的独立危险因素,回归系数分别为3.683、1.541、1.188、1.647.结论 避免早产、低出生体质量、长时间高气道压力、高氧浓度机械通气,预防NRDS、产前及产后感染,减少静脉营养应用时间是防治BPD的关键.

Abstract：

Objective To explore the incidence rate and high-risk factors for bronchopulmonary dysplasia(BPD) in premature infants of mechanical ventilation.Methods From Jan 2008 to Dec 2009,196 very low birth weight infants with gestational age less than 32 weeks in our NICU were enrolled in the study.61 cases had the histories of mechanical ventilation.The clinical materials of 21 cases with BPD were compared to 41 cases without BPD in retrospective analysis.Results The total incidence of BPD in the very low birth weight infants with gestational age less than 32 weeks was 10.7%,and 34.4% in those infants with mechanical ventilation.The gestational age and birth weight of BPD group were lower than those without BPD,and the rates of premature rupture of fetal membrane and complicated neonatal respiratory distress syndrome (NRDS),postnatal infection,with long time intravenous nutrition in BPD group were higher than those without BPO control (P<0.05).Gender,asphyxia history,the use of pulmonary surfactant (PS),positive end-expiratory pressure,and mean airway pressure were not different significantly between two groups (P>0.05).Peak inspiratory pressure (PIP),the time of mechanical ventilation and oxygen administration were different significantly between two groups (P<0.05).NRDS,postnatal infection,the duration of ventilation,and hyperoxia were the risk factors for BPD,and the regression coefficient were 3.683,1.541,1.188 and 1.647.Conclusion Preventing premature,low birth weight,NRDS,shortening the duration of high peak inspiratory pressure and hyperoxia with mechanical ventilation and the use of the parenteral nutrition,managing the infection of the prenatal and postnatal are the key points of preventing BPD.     

肺表面活性物质联合布地奈德预防极低出生体重儿支气管肺发育不良的疗效观察

目的探讨肺表面活性物质(PS)联合布地奈德气管内滴入预防极低出生体重早产儿支气管肺发育不良(BPD)的临床疗效。方法选取胎龄32周的患有宫内感染的呼吸窘迫综合征(NRDS)(Ⅲ或Ⅳ级)的极低出生体重儿30例,随机分成PS+布地奈德组(15例)和PS组(15例)。比较两组血气分析、氧合指数(OI)、呼吸机使用时间、吸氧时间、BPD发生率、纠正胎龄36周时病死率以及其他并发症的发生率。结果 PS+布地奈德组患儿BPD发生率低于PS组,呼吸机使用时间和吸氧时间明显短于PS组(P0.05);给药后第2~6天,PS+布地奈德组pH、OI均高于PS组,PaCO——2均低于PS组,且差异均有统计学意义(P0.05);两组间纠正胎龄36周时病死率以及其他并发症差异无统计学意义。结论 PS联合布地奈德气管内滴入能有效降低重度NRDS极低出生体重早产儿BPD的发生率。     

支气管肺发育不良患儿血清白细胞介素33的水平变化及临床意义

目的 探讨白细胞介素33（IL-33）在早产儿支气管肺发育不良（BPD）发生、发展中的作用及意义。方法 本研究采用前瞻性队列研究,选取胎龄≤32周和/或出生体重≤1 500 g的早产儿128例,根据病情分为非BPD组50例,轻度BPD组32例,中度BPD组30例,重度BPD组16例,收集所有早产儿母亲产前因素（母亲产前使用激素、母亲绒毛膜羊膜炎）、患儿产时因素（性别、胎龄、出生体重、分娩方式、出生窒息）、生后治疗情况（肺表面活性物质、有创通气时间、无创通气时间、肠外营养时间、总住院时间）;对各组早产儿分别于生后第1天、第14天、第28天采用酶联免疫吸附试验（ELISA）法检测血清IL-33水平,比较不同组别生后不同时间血清IL-33水平差异;对中重度BPD患儿确诊后采用传统激素治疗（DART方案）,检测治疗前后两组间血清IL-33水平变化。结果 BPD早产儿在母亲感染绒毛膜羊膜炎、胎龄、出生体重、出生窒息、有创通气时间、无创通气时间、肠外营养时间、总住院时间等方面,与非BPD早产儿比较,差异均有统计学意义（P < 0.05）,且上述指标在不同病情严重程度BPD早产儿组间比较差异有统计学意义（P < 0.05）。早产儿生后第1天、第14天、第28天,BPD组患儿血清IL-33水平高于非BPD组,且BPD病情程度越重,IL-33水平越高;随着生后时间的推移,BPD患儿血清IL-33水平有升高趋势（P < 0.05）。中重度BPD早产儿采用DART方案治疗后血清IL-33水平较治疗前均降低（P < 0.05）。结论 血清IL-33与BPD发生及病情严重程度密切相关,DART方案抗炎治疗可降低BPD患儿血清IL-33水平。     

Bronchopulmonary dysplasia in very low birth weight infants

Objective  The developments in newborn care have enabled many more very low birth weight premature infants to live. The aim of our study was to determine the risk factors for bronchopulmonary dysplasia (BPD) development by evaluating mild and moderate/severe BPD in extramural neonates with a birth weight <1501 g. Methods  A case-control study was conducted between January 1, 2004- December 31, 2006 at the Dr. Sami Ulus Children’s Hospital Neonatal Intensive Care Unit. Patients with BPD and without BPD were compared. Bronchopulmonary dysplasia was diagnosed and classified according to the Bancalari criteria. One-hundred and six (106) extramural premature infants with a birth weight <1501 g and admitted to the Neonatal Unit in the first three days of life and survived for more than 28 postnatal days were included. Patients with multiple congenital anomalies and complex cardiac pathologies were excluded. The maternal and neonatal risk factors, clinical features, mechanical ventilation treatment were compared. The principal risk factors for BPD development were analyzed and followed by logistic regression test. Results  The diagnosis was mild BPD in 27 of the 106 patients and moderate/severe BPD in 29. The incidence of BPD was 52.8%. Fifty of 106 patients had no BPD. Analysis of risk factors revealed that gestational age ≤28 weeks (p=0.019), birth weight ≤1000 g (p=0.007), hypothermia (p=0.003), acidosis (p=0.003) and hypotension (p=0.005) at admission, respiratory distress syndrome (RDS) ( p<0.001), mechanical ventilation therapy (p<0.001), surfactant therapy (p=0.005), higher amount of mean fluid therapy on 7^th days (p=0.008), nosocomial infection (p<0.001), higher amount of mean packed red cell transfusions (p<0.001) and more than two packed red cell transfusions (p=0.033) were risk factors associated with the development of BPD. Multivariant logistic regression analysis showed acidosis at admission (OR 5.12, 95%CI 1.17–22.27, p=0.029), surfactant treatment (OR 7.53, 95%CI 2.14–26.45, p=0.002), nosocomial infections (OR 4.66, 95%CI 1.27–17.12, p=0.02) and PDA (OR 9.60, 95%CI 2.23–41.22, p=0.002) were risk factors increasing the severity of BPD. Conclusion  The most important risk factors for BPD development in our study were RDS and nosocomial infections while the presence of acidosis at admission, surfactant administration, nosocomial infections and the presence of PDA were the most important risk factors regarding BPD severity. Presence of acidosis at admission as a risk factor emphasized the importance of suitable transport conditions for premature infants.     

Bronchopulmonary dysplasia and surfactant

Bronchopulmonary dysplasia (BPD) is the most common respiratory complication in preterm infants who survive prolonged mechanical ventilation. Exogenous surfactant administration clearly reduces the severity of respiratory distress syndrome (RDS) and consequently the need for aggressive ventilation and prolonged oxygen therapy. However, the overall incidence of BPD has not decreased but in fact may even have increased after the introduction of surfactant therapy. There are several reasons for the lack of effect on the incidence of BPD. First, surfactant therapy and antenatal steroids have markedly increased survival of the smallest infants, i.e. those at higher risk of BPD. Second, there has been a change in the pathogenesis and the presentation of BPD. While the classic BPD was mainly the consequence of barotrauma and oxygen toxicity, the new BPD seen in the surfactant era results from the interaction of many factors that lead to prolonged mechanical ventilation and colonization of the airway with pathogens that may trigger an inflammatory cascade. While the overall incidence of BPD has not been substantially modified by surfactant therapy, the more severe cases of BPD have become less common. The data regarding the effect of surfactant administration on the incidence and severity of BPD is conflicting. There is substantial evidence that the administration of exogenous surfactant, either as prophylaxis or as a treatment in infants with established RDS, can reduce neonatal mortality and the occurrence of BPD or death. The data also suggest that prophylactic or early administration is more effective than late treatment in reducing mortality and BPD or death. No clear difference has been documented between natural or synthetic surfactant treatment in terms of their effect on incidence of BPD or mortality. The lack of consistency in the results with surfactant replacement may reflect the changing pathogenesis of BPD and the multiplicity of factors involved among which surfactant deficiency is only one.     

Maternal glucocorticoid therapy and reduced risk of bronchopulmonary dysplasia

Because of substantial clinical and laboratory evidence of the efficacy of glucocorticoids in the treatment of acute pulmonary surfactant deficiency in preterm newborns, we explored the hypothesis that maternal antenatal glucocorticoid receipt is followed by reduced risk of bronchopulmonary dysplasia (BPD). A sample of 223 intubated infants weighing less than 1751 g birth weight provided 76 infants with BPD (defined by both oxygen requirement and compatible chest radiograph) and 147 who had neither BPD characteristic by day 28 of life. When compared to babies who received a complete and timely course of antenatal glucocorticoids, those whose mothers received no glucocorticoids were at prominently increased risk of BPD (odds ratio = 3.0; 95% confidence interval = 1.1, 8.2). Babies whose mothers received a partial course of glucocorticoids were not at increased risk of BPD (odds ratio = 1.3; 95% confidence interval = 0.4, 4.3). Stratification by gender and birth weight at 1 kg showed a benefit of therapy in all strata except that of extremely low birth weight male infants. These data support the hypothesis that maternal antenatal glucocorticoid therapy offers very low birth weight infants protection against BPD.     

Lower concentration of pulmonary hepatocyte growth factor is associated with more severe lung disease in preterm infants

OBJECTIVES: Hepatocyte growth factor (HGF) participates in normal lung development and in regeneration after lung injury in animals. We studied the role of HGF during the perinatal period and in the development of bronchopulmonary dysplasia (BPD). STUDY DESIGN: HGF was measured in 172 tracheal aspirate fluid samples (TAF) from 17 preterm infants in whom BPD subsequently developed (gestational age, 27.2+/-1.7 weeks; body weight, 828+/-210 g) and from 15 who survived without BPD (gestational age, 26.8+/-1.9 weeks; body weight, 994+/-265 g) during the first 2 postnatal weeks. RESULTS: Infants with subsequent development of BPD had lower HGF in TAF (45+/-9 pg/mL per IgA-sc) than those surviving without BPD (102+/-32 pg/mL per IgA-sc; P=.028). Lower HGF in TAF were seen in infants with more severe acute respiratory distress as defined as requirement for surfactant therapy (50+/-14 vs 146+/-50 pg/mL per IgA-sc in infants requiring no surfactant; P=.0001), for higher number of surfactant doses (r=-0.16, P=.06), and for mechanical ventilation >1 week (167+/-51 vs 51+/-14 pg/mL per IgA-sc in infants intubated <1 week; P=.0012). CONCLUSIONS: These data show an association between lower HGF concentration in TAF and more severe lung disease in human preterm infants in the early neonatal period.     

早产儿支气管肺发育不良严重程度的影响因素

目的 探讨早产儿支气管肺发育不良（BPD）严重程度的影响因素。方法 收集2011 年1 月至2013 年12 月住院28 d 以上的明确诊断为BPD 的早产儿110 例,根据临床分度标准分为轻度BPD（52 例）、中度BPD（44 例）、重度BPD（14 例）,探讨不同分度BPD 与出生胎龄、出生体重、窒息、吸氧、母亲妊娠并发症、宫内感染性肺炎及机械通气等因素的关系。结果 不同分度BPD 与出生胎龄、出生体重、母亲产前感染、吸氧浓度>40% 的持续时间、是否机械通气、机械通气参数、机械通气时间、持续气道正压通气（CPAP）时间、是否采用INSURE 模式及是否合并解脲脲原体感染、宫内感染性肺炎及动脉导管未闭有关。有序logistic 回归分析显示机械通气参数中的吸气峰压（OR=1.260,95%CI：1.096~1.448）、机械通气时间（OR=1.010,95%CI：1.005~1.016）为BPD 严重程度的独立危险因素,采用INSURE 模式为保护因素（OR=0.208,95%CI：0.060~0.923）。结论 早产儿BPD 严重程度与多种因素有关;避免低出生体重早产儿出生、缩短应用机械通气时间、防止和减少肺部感染以及尽量采用INSURE 技术是预防BPD 进展的重要措施。     

气泡式与鼻塞式持续气道正压通气在早产儿呼吸窘迫综合征的疗效比较

目的 比较气泡式持续气道正压通气（BNCPAP）与鼻塞式持续气道正压通气（nCPAP）在早产儿呼吸窘迫综合征（NRDS）呼吸支持中的疗效及安全性。方法 回顾性分析使用过BNCPAP（69例）或nCPAP（61例）呼吸支持的130例早产NRDS患儿的临床资料,比较两组的死亡率、呼吸支持时间、是否使用肺表面活性物质（PS）以及治疗失败、支气管肺发育不良（BPD）、早产儿视网膜病（ROP）的发生情况,和上机后血气分析的pH、氧分压、二氧化碳分压的变化情况,并评价其安全性。结果 BNCPAP、nCPAP两组患儿在性别分布、出生胎龄及体重、1 min及5 min Apgar评分及出生方式、NRDS严重程度等方面的差异无统计学意义（P > 0.05）。BNCPAP组无患儿死亡,nCPAP组有1例死亡,但两组病死率的差异无统计学意义（P > 0.05）。BNCPAP组及nCPAP组无创辅助通气的时长、治疗失败率、BPD和ROP的发生率以及需要使用或需要重复使用PS比例的差异均无统计学意义（P > 0.05）。两组患儿上机后8~12 h的pH值变化及氧合指数变化的差异无统计学意义（P > 0.05）,但BNCPAP组患儿的二氧化碳分压下降较nCPAP组患儿多（P < 0.05）。两组患儿气胸及鼻中隔、鼻黏膜损伤发生率的差异无统计学意义（P > 0.05）。结论 BNCPAP和nCPAP在早产儿NRDS呼吸支持中的疗效和安全性相近。     

不同程度支气管肺发育不良早产儿的临床及影像学特点

目的　探讨不同程度支气管肺发育不良(BPD)早产儿的临床及影像学特点。方法　对59例胎龄<32周BPD 早产儿的临床及影像学特点进行前瞻性研究。59例早产儿中包括轻度BPD 37例, 中/重度BPD 22例, 比较不同程度BPD患儿的临床及影像学表现。结果　中/重度BPD组患儿机械通气、氧疗、抗生素、静脉营养等应用时间及住院时间长于轻度BPD组(P<0.05), 院内感染发生率、红细胞输注次数高于轻度BPD组(P<0.05)。轻度BPD组呼吸窘迫综合征(RDS)Ⅰ级(生后1 d)、肺透亮度减低(生后4~10 d、生后28 d及以上)等X线改变比例较中/重度BPD组高(P<0.05); 中/重度BPD组BPD Ⅲ期改变(生后4~10 d)、BPD Ⅳ期改变(生后28 d及以上)等比例较轻度BPD组高(P<0.05)。结论 呼吸机、氧疗、抗生素等应用时间及院内感染发生率与BPD严重程度相关。BPD程度越重的患儿, 静脉营养时间越长, 输注红细胞次数越多, BPD影像学改变更典型。BPD影像学检查对BPD的严重程度有一定的预测作用。     

早产儿出生时血清25-羟维生素D水平与支气管肺发育不良的相关性

目的分析早产儿出生时血清25-羟维生素D[25(OH)D]水平与支气管肺发育不良(BPD)的关系。方法选取2014年1月至2016年12月入住NICU、出生胎龄34周的早产儿,按是否患BPD分为BPD组(41例)和对照组(219例),分析25(OH)D水平与BPD的关系。结果 BPD组血清25(OH)D水平显著低于对照组(37±17 nmol/L vs 47±20 nmol/L;P0.05);维生素D缺乏率显著高于对照组(90.2%vs 74.0%,P0.05)。血清25(OH)D水平与BPD发生率呈负相关(r=-0.201,P=0.001)。结论早产儿维生素D缺乏可能与BPD发病有关,但需多因素分析进一步证实。     

What is bronchopulmonary dysplasia and does caffeine prevent it?

Bronchopulmonary dysplasia (BPD) is among the most severe complications of very premature birth. Clinical and laboratory studies indicate that lung immaturity, inflammatory lung injury, and disordered lung repair are the primary mechanisms responsible for the development of BPD. Caffeine, initiated within the first 10 days after birth, is one of few drug therapies shown to significantly decrease the risk of BPD in very low birth weight infants. This benefit is likely derived, at least in part, from reduced exposure to positive airway pressure and supplemental oxygen with caffeine therapy. Additional cardiorespiratory benefits of caffeine that may contribute to the lower risk of BPD include less frequent treatment for a PDA, improved pulmonary mechanics, and direct effects on pulmonary inflammation, alveolarization, and angiogenesis. Routine administration of caffeine is indicated in the vast majority of very low birth weight infants. However, current preventative strategies including widespread use of caffeine do not avert BPD in all cases. As such, there is continued need for novel methods to further reduce the risk of BPD in very low birth weight infants.     

Development of chronic lung disease in preterm infants treated with surfactant

BACKGROUND: Chronic lung disease (CLD) is generally known to develop among preterm infants who have severe respiratory distress syndrome (RDS) at birth. Many clinical trials have established the efficacy of surfactant replacement therapy to treat RDS at birth with differing doses. In this study, the preterm infants diagnosed to have RDS at birth and treated with one or two doses of surfactant, depending on the severity of the RDS, were studied to evaluate the effect of surfactant on the later development of CLD. METHODS: A retrospective examination of case records of preterm infants who were born at < or = 28 weeks gestation period were studied. The subjects received a natural surfactant product (survanta) between September 1994 and April 1996 at the Monash Medical Center, Australia. RESULTS: Despite less severe initial lung disease, the subsequent respiratory outcome of infants who received one dose of surfactant, showed a trend towards being poorer compared to those who were diagnosed as having severe RDS at birth and received two doses of surfactant. At the corrected gestational age of 36 weeks, 54% of those infants began with mild RDS required oxygen, while only 44% of those who started with a severe RDS required supplemental O2. CONCLUSION: This study reports the infants with severe RDS at birth had responded slightly better or equally, compared to those with mild RDS, in terms of later development of CLD under surfactant treatment proportional to the severity.     

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??Postnatal glucocorticoid is an effective therapy for preventing or treating bronchopulmonary dysplasia??BPD?? among extremely preterm infants??but the side-effect profile limits its use and makes it an unacceptable option for many patients. Early low-dose hydrocortisone therapy may be beneficial to premature infants with intrauterine chorioamnionitis??but concerns remain about possible adverse effects such as gastrointestinal perforation. Late??after the first week of life?? postnatal steroids may have a better benefit-to-harm ratio than early steroids. Postnatal dexamethasone??DEX?? in 2-3 weeks after birth should mainly be reserved for infants who cannot be weaned from mechanical ventilation and the dose and duration should be kept to a minimum. However??early inhalation of budesonide or intratracheal instillation of budesonide using surfactant as a vehicle can reduce the incidence of BPD??but its safety needs further evaluation. Future studies are required to identify the preferred type??dose and timing of therapy that will provide maximal benefit with minimal side effects.     

不同剂型布地奈德联合肺表面活性物质治疗新生儿呼吸窘迫综合征疗效的比较

目的比较不同剂型布地奈德联合肺表面活性物质(PS)对新生儿呼吸窘迫综合征(NRDS)患儿血气改善及支气管肺发育不良(BPD)发生的影响。方法将出生4 h内发生NRDS的早产儿184例随机分为4组,每组46例:PS+布地奈德气雾剂持续喷入组(简称气雾持续组)、PS+单剂布地奈德液体剂型组(简称液体组)、PS+布地奈德气雾剂单剂喷入组(简称气雾单次组)、单用PS组。比较4组治疗后动脉血气的变化及治疗后改为有创机械通气率、辅助通气时间、重复使用PS率及BPD发生率。结果治疗后第2~4天4组pH、PCO_2、氧合指数(FiO_2/PaO_2)比较差异均有统计学意义,各指标改善效果依次为气雾持续组、液体组、气雾单次组、单用PS组。气雾持续组辅助通气时间明显短于其他3组(P0.05),液体组明显短于气雾单次组及单用PS组(P0.05)。4组治疗后改用有创机械通气率、重复使用PS率及BPD发生率的比较差异均有统计学意义,其中气雾持续组这3个指标的发生率均最低,其次为液体组。结论气雾剂型布地奈德持续喷入联合PS治疗NRDS的疗效优于单剂液体剂型,但两者在降低BPD发生率方面的差异有待扩大样本量进一步研究。     

小胎龄早产儿支气管肺发育不良发生率和危险因素分析

目的探讨小胎龄早产儿支气管肺发育不良(BPD)的发生率和高危因素。方法回顾性分析2008年5月至2011年12月我院新生儿科收治、胎龄≤32周、且存活28天以上的早产儿临床资料,发生BPD的早产儿为BPD组,按1∶2的比例随机选取未发生BPD的早产儿为对照组。结果共纳入197例早产儿,BPD组28例,BPD发生率14.2%,早产儿随胎龄和出生体重降低BPD发生率明显增加,各胎龄段和体重组差异均有统计学意义(χ2=32.269,30.244,P=0.000)。通过对23个单因素的分析发现,BPD组和对照组胎龄、出生体重、吸氧时间、最高吸入氧浓度、住院时间、气管插管机械通气、应用肺表面活性物质治疗、贫血、使用美罗培南、第10天体重/出生体重比值、氧合指数<300和生后第1次血气评分值12个单因素差异有统计学意义(P均<0.05);多因素Logistic回归分析发现,出生体重低(OR=0.996)、吸氧浓度高(OR=0.898)、第10天体重/出生体重比值小(OR=1.069)为发生BPD的高危因素(P均<0.05)。中重度BPD组与轻度BPD组相比,窒息和使用利尿剂比例高、吸氧时间长、生后第1次血气评分低,差异有统计学意义(P均<0.05)。结论出生体重低、吸入高浓度氧、第10天体重/出生体重比值低为小胎龄早产儿发生BPD的高危因素。     

Population-based study of bronchopulmonary dysplasia in very low birth weight infants in Switzerland

In Switzerland, data are collected prospectively by collaborators from all nine neonatal intensive care units and their affiliated paediatric units caring for neonates, to determine survival and (pulmonary) outcome of infants with birth weights ranging from 501 to 1500 g. To assess the pulmonary outcome of very low birth weight (VLBW) infants in Switzerland in 1996 and 2000, factors associated with bronchopulmonary dysplasia (BPD) were identified and compared with pulmonary outcomes from the Vermont Oxford Network data. BPD was defined as a requirement for supplemental oxygen at 36 weeks postmenstrual age. Complete data were available for 600 and 636 VLBW infants in 1996 and in 2000, respectively. Mortality rates in Switzerland were significantly higher (1996: 19.2%, 2000: 20.8%) than in the Vermont Oxford Network (1996: 14%, 2000: 14%). Expressed as percentage of infants still hospitalised at 36 weeks postmenstrual age, 16.7% and 13.2% of Swiss VLBW infants were diagnosed with BPD in 1996 and 2000, respectively. These rates were significantly lower than in the Vermont Oxford Network (1996: 28%, 2000: 35%). Infants exposed to factors previously shown to be associated with BPD were investigated: in Switzerland, infants with a history of surfactant replacement therapy and/or mechanical ventilation had a significantly higher rate of BPD in both cohorts. Infants with postnatal transport, sepsis proven by positive blood culture and patent ductus arteriosus had a higher BPD rate only in the 1996 cohort. Between 1996 and 2000, mortality rates and incidence of BPD in VLBW infants remained unchanged in Switzerland. BPD rates in Switzerland are lower than those found in the Vermont Oxford Network whereas a mortality rate comparison displays an inverted picture. We suspect that these effects are interrelated and may be due in part to a selective approach of Swiss neonatologists to resuscitation of infants in the smallest birth weight stratum. Conclusion:The factors listed above have apparently become less important in the context of bronchopulmonary dysplasia and other influences, including prenatal conditions, will need to be investigated.     

Association between fluid intake and weight loss during the first ten days of life and risk of bronchopulmonary dysplasia in extremely low birth weight infants

OBJECTIVE: To demonstrate the association between fluid intake and weight loss during the first 10 days of life and the risk of bronchopulmonary dysplasia (BPD) in extremely low birth weight (ELBW) infants. STUDY DESIGN: A retrospective analysis of data from a cohort of ELBW infants enrolled in the Neonatal Research; 1,382 infants with birth weight between 401 and 1,000 g were randomized. The daily fluid intake and weight loss during the first 10 days of life were compared between the infants who survived without BPD and those who either died or developed BPD. Demographic and clinical neonatal variables were also compared. Multivariate logistic regression was used to analyze the effect of fluid intake and weight loss on death or BPD, controlling for demographic and clinical factors that are significantly associated with BPD by univariate analysis. RESULTS: 585 infants survived without BPD and 797 infants either died or developed BPD. Univariate analysis showed that the daily fluid intakes were higher (day 2-10) and weight loss less (day 6-9) in the group of infants who either died or developed BPD. In addition, lower birth weight, lower gestational age, male gender, lower 1 and 5-minute Apgar Scores, higher oxygen requirement at 24 hours of age, longer duration of assisted ventilation, use of postnatal steroids for BPD and presence of severe intraventricular hemorrhage, proven necrotizing enterocolitis, patent ductus arteriosus, and late onset sepsis, were associated with higher incidence of death or BPD. The adjusted risk of higher fluid intake and less weight loss during the first 10 days of life remained significantly related to death or BPD. CONCLUSION: In this cohort of ELBW infants treated during the post surfactant era, higher fluid intake and less weight loss during the first 10 days of life were associated with an increased risk of BPD. The finding suggests that careful attention to fluid balance might be an important means to reduce the incidence of BPD.     

Bronchopulmonary dysplasia – prevalence,severity and predictive factors in a national cohort of extremely premature infants

Aim: To study prevalence and predictive factors of bronchopulmonary dysplasia (BPD) in a cohort of preterm infants with a high incidence of prenatal steroid and surfactant treatment. Methods: BPD was analysed in a national cohort of infants with gestational age (GA) of 22–27 completed weeks (wks) or birth weight (BW) of 500–999 g. Of 464 infants who were transferred to a NICU, 377 infants with GA ≤ 30 wks and survived beyond 28 days were included in the study. Results: Moderate or severe BPD was strongly related to GA. Of infants with GA 22–25 wks, 67.3% developed BPD compared to 36.6% at GA 26–30 wks. Overall, moderate and severe BPD was significantly more common in boys (63.3%) than in girls (36.6%) (p = 0.0004), but female gender was not a protective factor in infants with GA 22–25 wks. In multivariate analyses, BPD was significantly associated with gender, surfactant treatment and treatment for PDA. Conclusions: BPD remains a severe complication of extreme prematurity in spite of prenatal steroids and surfactant treatment. Whether associations with surfactant and PDA treatment simply reflect severity of early lung disease or have causal relationships should probably be studied in randomized controlled trials.