Neonatal Respiratory Distress Syndrome NRDS 新生儿呼吸窘迫综合征,站,Definition,Hyaline membrane disease， HMD Deficiency of pulmonary surfactant，PS Pulmonary alveoli collapse at the end of expiration Progressively aggravated respiratory distress shortly after birth Mainly in preterm infant Higher incidence rate with smaller gestational age Infant of DM mother, cesarean section, the second baby of twins,Etiology,PS are secreted by type II epithelial cells of pulmonary alveoli. Dipalmitoyllecithin（DPPC） is the main substance. Surfactant protein（SP） PS are produced from 1820w till 3536w when lung is mature.,Etiology,PS cover the inner surface of pulmonary alveoli, which can: decrease alveolar surface tension prevent alveoli collapse at the end of expiration keep functional residual capacity（FRC） keep stable pulmonary alveolus pressure decrease fluid exude from capillary to pulmonary alveoli,Etiology,Preterm birth pH of body fluid, body temperature, volume of pulmonary blood flow and hormone can influence PS secretion. Asphyxia, hypothermia, placenta previa, placental abruption and hypotension of mother, which can influence blood flow of fetus. High level insulin of IDM may resist the promotion effect of adrenal cortex hormone to PS synthesis,Pathogenesis,PS deficiency,alveolar surface tension,alveolus collapse and pulmonary compliance,work at inspirationdifficulty at alveolus opening,tidal volume,alveolar ventilation,CO2 retention,respiratory acidosis,V/A,hypoxia,metabolic acidosis,Alveolar permeability,interstitium edema,fibrin deposition in the inner surface of alveoli,eosinphilic hyaline membrane,gas diffusion disorder,Clinical manifestation,Respiratory distress 26h after birth: dyspnea, cyanosis, flaring of alaenasi, inspiratory three-concave sign, expiratory groan Progressively aggravated respiratory distress Flat thorax, low breath sound, wet rales Arterial duct opening at convalescence stage Condition will improve after 3d but the course will longer if complications exist.,Assistant examination,Laboratory examinations： foam test lecithin/sphingomyelin（L/S） blood gas analysis Chest X ray： frosted glass-like changes air bronchogram white lung color Doppler ultraphonic：PPHN, PDA,Diagnosis,Clinical manifestations Chest X ray,站,Differential diagnosis,wet lung group B streptococcal pneumonia diaphragmatic hernia,Therapy,General treatment： incubation monitoring of T, R, HR, BP, blood gas liquid and nutrition Supply Rectification of acidosis shut off arterial ductus antibiotics,Oxygen therapy and assistant ventilation： oxygen inhalans constant positive airway pressure(CPAP) ventilation common frequency ventilator high frequency oscillation ventilator, high frequency ejection ventilator extracorporeal membrane oxygenator (ECMO),Therapy,Therapy,PS substitution therapy： Natural, semisynthesis, artificial synthesis utilization：pump into airway through intra-tracheal tube within 24h after birth Repeat 24 times if requirement,Prevention,Prevention of preterm labor Promotion of fetal lung maturity Prophylactic using PS,Summary,站,