OBJECTIVE:A meta-analysis of published randomized controlled trials investigating the long-term effect of dexamethasone on the nervous system of preterm infants.
DATA SOURCES:Online literature retrieval was conducted using The Cochrane Library (from January 1993 to June 2013), EMBASE (from January 1980 to June 2013), MEDLINE (from Janu-ary 1963 to June 2013), OVID (from January 1993 to June 2013), Springer (from January 1994 to June 2013) and Chinese Academic Journal Full-text Database (from January 1994 to June 2013). Key words were preterm infants and dexamethasone in English and Chinese.
STUDY SELECTION:Selected studies were randomized controlled trials assessing the effect of intravenous dexamethasone in preterm infants. The quality of the included papers was evaluated and those without the development of the nervous system and animal experiments were exclud-ed. Quality assessment was performed through bias risk evaluation in accordance with Cochrane Handbook 5.1.0 software in the Cochrane Collaboration. The homogeneous studies were analyzed and compared using Revman 5.2.6 software, and then effect model was selected and analyzed. Those papers failed to be included in the meta-analysis were subjected to descriptive analysis.
MAIN OUTCOME MEASURES:Nervous system injury in preterm infants.
RESULTS:Ten randomized controlled trials were screened, involving 1,038 subjects. Among them 512 cases received dexamethasone treatment while 526 cases served as placebo control group and blank control group. Meta-analysis results showed that the incidence of cerebral palsy, visual im-pairment and hearing loss in preterm infants after dexamethasone treatment within 7 days after birth was similar to that in the control group (RR=1.47, 95%CI:0.97-2.21;RR=1.46, 95%CI:0.97-2.20;RR=0.80, 95%CI:0.54-1.18;P>0.05), but intelligence quotient was signiifcantly de-creased compared with the control group (MD=-3.55, 95%CI:-6.59 to-0.51;P=0.02). Prete rm infants treated with dexamethasone 7 days after birth demonstrated an incidence of cerebral palsy and visual impairment, and changes in intelligence quotient similar to those in the control group (RR=1.26, 95%CI:0.89-1.79;RR=1.37, 95%CI:0.73-2.59;RR=0.53, 95%CI:0.32-0.89;RR=1.66, 95%CI:-4.7 to 8.01;P>0.05). However, the incidence of hearing loss was signiifcantly increased compared with that in the control group (RR=0.53, 95%CI:0.32-0.89;P=0.02).
CONCLUSION:Dexamethasone may affect the intelligence of preterm infants in the early stages after birth, but may lead to hearing impairment at later stages after birth. More reliable conclusions should be made through large-size, multi-center, well-designed randomized controlled trials.

支气管肺发育不良的防治——证据及临床应用

The knowledge on the pathogenetic mechanisms of bronchopulmonary dysplasia (BPD) has increased considerably over recent years. However, the incidence of the disease has not substantially been changed by our therapeutic approaches. This review summarizes the existing evidence for a number of respiratory and medical strategies to prevent or ameliorate the disease and gives recommendations for clinical practice. Oxygen plays an important pathogenetic and therapeutic role for BPD. Targeting infants at lower oxygen saturation levels than traditionally used seems to confer major advantages. There is no sufficient evidence for a routine use of respiratory strategies like permissive hypercapnia or inhaled nitric oxide to prevent BPD. Diuretics can ameliorate lung function transiently. High intramuscular doses of vitamin A can reduce the risk of BPD. Early or prophylactic surfactant might also be advantageous. Postnatal corticosteroids are effective but,due to their severe side effects, should be restricted to the severest cases. Alpha1-proteinase inhibitor and superoxide dismutase have no proven benefits for BPD. The role of erythromycin has not been completely elucidated yet. Innovative strategies like Clara Cell 10kD protein still have to be assessed in future trials.