新生儿呼吸窘迫综合征(NRDS)英文.ppt

单击此处编辑母版标题样式,*,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,Neonatal Respiratory Distress Syndrome(NRDS),Tongji Hospital,Neonatal Respiratory Distress Syndrome(NRDS)or:Hyaline Membrane Disease(HMD),Most common cause of respiratory failure in the first days,Occurring in 12%of newborn infants(GA 2628w,50%,3031w,less than 2025%),Mortality 50%at 20 yrs ago,Survive 8090%now,High risk:IDM,GA90%reuse,Surfactant Composition,Phospholipid,90%(neutral 5%),saturated 50unsaturated 35,Protein10(albumin 5%),SP-A,3035kDa,18 ologomer,hydrophilic,D,43kDa,12 oligomer,SP-B,8kDa,dimer,hydrophobic,C,4kDa,dimer,Function of Pulmonary Surfactant,Decrease alveolar surface tension,reduce respiratory work,Maintain alveoli,inflation,and,functional residual capacity,Accelerate lung fluid absorption,reduce alveolar effusion,Pathogen Opsonization,alveolar macrophage activation,Effects:,improve oxygenation,ameliorate ventilation/perfusion,anti-inflammation,Fluid surface tension,Pressure(P)=,2xsurface tension(,),radius,(r),Etiology and Pathophysilogy,Surfactant lowers the surface tension of,alveolar membrane,Pulmonary immaturity results in surfactant,deficiency,Alveoli collapse at the end of expiration,leads to respiratory failure,Surfactant deficiency can arise after,asphyxia/shock and acidosis,Pathology,atelectasis,pulmonary edema,vascular congestion,hemorrhage,generalized capillary leak and mucosal necrosis leads to the small air filled terminal airways,the respiratory bronchioles and alveolar ducts,being surrounded by collapsed alveoli filled with debris in a near uniform distribution(,hyaline membranes,),Pathophysiology,Lack of alveolar surfactant in the lungs of infants,Avery and Mead,Am J,Dis,Child,1959,progressive,atelectasis,loss of functional residual capacity(FRC),alteration of ventilation-perfusion ratio,Weak respiratory muscles and compliant chest wall,impair alveolar ventilation,Diminished oxygenation,cyanosis and acidosis,increased pulmonary vascular resistance(PVR),right-to-left shunting through,ductus arteriousus,intrapulmanary,ventilation-perfusion mismatch,Clinical Presentation,Present at birth or within several hours after birth:,tachypnea,grunting,retractions,cyanosis with increasing oxygen requirements,Physical findings:,rales,poor air exchange,use of accessory muscles of breathing,nasal flaring,abnormal patterns of respiration with apnea,Radiographic Changes of RDS,a bell shaped thorax with diffuse and symmetrical,“ground glass”,infiltrates,air bronchograms and decreased lung volume,or severe bilateral opacity characterized by the term of,“white out”,Laboratory Findings,Respiratory and metabolic acidosis,Phospholipid,(PL)/,Sphingomyelin,(S)0.6,PaO,2,50mmHg or TcSO,2,85%,Pressure:,410cm H,2,O,flow 5L/min,32,C,humidity 100%,Conventional Mechanical Ventilation(CMV),Indication:,PaO,2,50mmHg or TcSO,2,70mmHg;or frequent apnea,Complication:,PAL(pulmonary air leak),BPD(,bronchopulmonary,dysplasia,;or CLD),RLF(,retrolental,fibroplasia,),VAP(ventilator-associated pneumonia),Application of Pulmonary Surfactant,Intratracheal instillation:50200mg/kg,612h interval,Neonatal Respiratory Distress Syndrome(NRDS),meconium,aspiration syndrome(MAS),Pneumonic Respiratory failure,Acute lung injury,ARDS,Respiratory failure after open-chest surgery or lung transplantation,Prevention,Careful maternal care and fetal monitoring,Avoidance of asphyxia and infection at birth,Maternal,glucocorticoids,(,betamethasone,12mgX2,im,24h apart,dexamethasone,6mgX4,im,6h apart),Preventive use of surfactant,The most effective way to prevent RDS is to prevent preterm delivery.If preterm delivery is inevitable,attempts to“mature the fetus”are reasonable.,