新生儿黄疸（英文）.ppt

1、Neonatal Jaundice(Hyperbilirubinemia)Introduction All All babies babies develop develop elevated elevated serum serum bilirubin bilirubin(SBR)(SBR)levels,levels,to to a a greater greater or or lesser lesser degree,degree,in in the the first first week week of life.This is due to:of life.This is due

2、to:increased production(accelerated RBC breakdown);increased production(accelerated RBC breakdown);decreased removal(liver enzyme insufficiency)decreased removal(liver enzyme insufficiency)Increased reabsorption(enterohepatic circulation).Increased reabsorption(enterohepatic circulation).Introductio

3、n 60%of infants become clinically jaundiced in 1 60%of infants become clinically jaundiced in 1st st wk wk Bili levels peak at 35 days in full term infants Bili levels peak at 35 days in full term infants 1/6 of formula fed infants have bili levels over 12 1/6 of formula fed infants have bili levels

4、 over 12 1/3 of breast fed infants have bili levels over 12 1/3 of breast fed infants have bili levels over 12 Over 80%of all infants with bili levels12.9 mg/dl in Over 80%of all infants with bili levels12.9 mg/dl in the first four days of life are breast fed the first four days of life are breast f

5、edBilirubin Metabolism derived from the catabolism of proteins that contain derived from the catabolism of proteins that contain hemeheme the most important source is the breakdown of the most important source is the breakdown of HbHb from RBC from RBC native bilirubin is relatively insoluble in wat

6、er at physiologic native bilirubin is relatively insoluble in water at physiologic pH,but it is very lipid soluble pH,but it is very lipid soluble bilirubin bilirubin circulates circulates bound bound to to albumin albumin in in equilibrium equilibrium with with its its unbound or free fractionunbou

7、nd or free fractionthe the unbound unbound fraction fraction that that readily readily crosses crosses the the blood-brain blood-brain barrier and results in barrier and results in neurotoxicityneurotoxicityBilirubin Metabolism Bilirubin Bilirubin is is made made more more water-soluble water-solubl

8、e in in the the liver liver by by conjugation conjugation withwith glucuronicglucuronic acid acid to to form form conjugated conjugated or or direct-reacting direct-reacting bilirubin,bilirubin,then then cleared cleared through through the the bile bile into into the intestines and out through the f

9、eces.the intestines and out through the feces.PhototherapyPhototherapy works works by by producingproducing photoisomersphotoisomers of of bilirubin bilirubin that that are are more more water water soluble,soluble,and and that that can can be be cleared cleared directly directly in in bile or urine

10、 without conjugation in the liver.bile or urine without conjugation in the liver.“enterohepatic circulation”:b b-glucuronidase in the gut hydrolysis the conjugated bilirubin into unconjugated bilirubin,and reabsorbed into liverCharacteristics of Neonatal Bilirubin Metabolism Increased bilirubin prod

11、uction Increased bilirubin production 8.8mg/kg daily 8.8mg/kg daily vs vs 3.8mg/kg in adults3.8mg/kg in adults Insufficiency of bilirubin transportationInsufficiency of bilirubin transportation acidosis,acidosis,hypoalbuminemiahypoalbuminemia Immature of liver functionImmature of liver function lowe

12、r ingestion(y,z protein);lower UDPGT activitylower ingestion(y,z protein);lower UDPGT activity Increased Increased“enterohepatic circulation”lower in gut bacteria;higher b b-glucuronidase activity“Physiological”Jaundice Seen in 60%of term infants and over 80%of preterm Seen in 60%of term infants and

13、 over 80%of preterm Serum values reaches maximum at 6mg/dl on 45d in Serum values reaches maximum at 6mg/dl on 45d in term and 1012mg/dl on 57d in premature infants term and 1012mg/dl on 57d in premature infants Jaundice declines gradually,reaching normal values Jaundice declines gradually,reaching

14、normal values within 2 wks in term,and 34w(12m)in preterm within 2 wks in term,and 34w(12m)in preterm Causes no damage in term infants Causes no damage in term infants Up limit for abnormal?Undefined(Term 12mg/dl,or term13,preterm1215mg/dl,or 5mg/dl/day Severe jaundice:SBR1215mg/dl,or 5mg/dl/day Sus

15、tained jaundice(term2w,Sustained jaundice(term2w,pretermpreterm4w)4w)Recurrence of jaundice Recurrence of jaundice Increased Increased serum serum conjugated conjugated bilirubin bilirubin(1.52mg/dl)(1.52mg/dl)Pathological Jaundice Infectious diseases Infectious diseases Neonatal hepatitis(Torch inf

16、ection)Neonatal hepatitis(Torch infection)Neonatal septicemiaNeonatal septicemia Non-infectious diseases Non-infectious diseases Hemolytic diseasesHemolytic diseasesBiliary atresiaBreast milk jaundiceGenetic metabolic diseases:G6PD,a a1-antitrypsin,CFDrugs induced:Vitamin K3,K4Breast Milk JaundiceOc

17、curs Occurs infrequently infrequently(1%),(1%),peaks peaks in in 23wk,23wk,may may persist persist at at moderately high levels for 3-4 weeks before declining slowly moderately high levels for 3-4 weeks before declining slowly It is a diagnosis of exclusionIt is a diagnosis of exclusionIn an otherwi

18、se well infant,it is considered a benign condition.In an otherwise well infant,it is considered a benign condition.If breast feeding stopped,the serum bilirubin usually fallsIf breast feeding stopped,the serum bilirubin usually fallsThe The potential potential harms harms of of stopping stopping bre

19、ast breast feeding feeding would would outweigh outweigh any risks of a mild or moderate hyperbilirubinaemiaany risks of a mild or moderate hyperbilirubinaemiaAetiology Aetiology is is unknown,unknown,some some hormonal hormonal in in the the milk milk may may acting acting on on the the infants inf

20、ants hepatic hepatic metabolism,metabolism,or or enzyme enzyme(lipase)(lipase)facilitating intestinal absorption of bilirubin.facilitating intestinal absorption of bilirubin.Breast-feeding Jaundice increased increased bilirubin bilirubin levels levels seen seen during during the the first first week

21、 week of of life life in infants who are breast fedin infants who are breast feddue due to to both both caloric caloric deprivation deprivation(mostly)(mostly)and and some some fluid fluid deprivation(a small part)during the first few days of lifedeprivation(a small part)during the first few days of

22、 lifeThe The more more frequently frequently breast breast feeding feeding occurs occurs during during the the first first few days,the lower are subsequentfew days,the lower are subsequent bili bili levels levelscan can be be prevented prevented by by teaching teaching effective effective breast-fe

23、eding breast-feeding practices and support policiespractices and support policiesClinical Investigation:Kramers RuleZone12345SBR(m mmol/L)100 150 200 250 250Cephalocaudal Progression of JaundiceClinical Investigation Total SBR conjugated SBR full blood count-may reveal spherocytes or septic Group&Di

24、rect Coombs test hemolytic jaundice high TSH&low T4-suspect thyroid disease G6PD screen-male and appropriate ethnic group sepsis screen if indicated galactosaemiaRhesus isoimmunisation Rh antigen:C,D,E,c,d,e most common type is RhD Rh(-)refers to D-Rare in un-transfused 1st pregnancy In severe cases

25、 fetal anaemia develops,causing congestive cardiac failure(hydrops fetalis)The fetus is protected with placental removal of bilirubin,following rapidly rising SBR after birth ABO Incompatibility Most often seen in the setting of mother being group O and the baby being groups A or B Milder that Rhesu

26、s disease,rarely affects the fetus Jaundice that becomes apparent on day 1 or 2 Diagnosis with blood groups and direct Coombs Test Responds well to phototherapy Rarely requires exchange transfusion1/5 for ABO,1/20 for Rh incompatibility will becoming hemolyticClinical Manifestation Jaundice:within 2

27、4h in 77%of Rh,28%in ABO Anemia Hepatosplenomegaly Bilirubin encephalopathy(Kernicterus)Early(27d):more in preterm,includes hypertonia,lethargy,feeding difficulty,seizures,1/3 death,bilirubin staining of the basal gangiaLate:Survivors may go on to develop sensorineural hearing loss and cerebral pals

28、y,often with ataxia and choreoathetosis;disorders in eye movement;enamel hypoplasiaDiagnosis Family history:still birth,abortion,jaundice Parents ABO/Rh typing,antibody Ultrasound for hydrops fetalis Postnatal:jaundice,anemia,neurological symptom Blood type and antibodyDirect Coombs,Antibody release

29、,&Free antibody TestManagement Prenatal:Rh(-),monitoring antibody,bilirubin,etcTerminate pregnancy when lungs are maturedPlasma transfusion to remove antibodyIntrauterine blood transfusionMaternal use of phenobarbitone to induce enzymePhototherapyIsomerisation of unconjugated bilirubin Wave length:4

30、27475nm(blue),510530nm(green)Blue light,green light/day lightProtection of eyes/gonadInvisible water lossSide effects:skin rash,fever,diarrheaBeware of conjugated hyperbilirubinemia(bronze baby)PhototherapyExchange TransfusionPrenatal diagnosed,Hb12 m mmol/L/hr(0.75mg/dl)SBR 342 m mmol/L(20mg/dl)Pre

31、term/Rh history/Hypoxia/Acidosis/SepsisFor Rh:Rh same as mother,ABO same as infantFor ABO:AB/plasma and O/RBS;or type OVolume:150180ml/kg via umbilical vein catheter Other InterventionAlbumin(1g/kg),plasma(25ml)Correct acidosisPhenobarbitone(5mg/kg)to induce enzymesIntravenous immunoglubulin(1g/kg)Prevent hypoxia/hypothermia/hypoglycemiaAnti RhD IgG(300m mg,im)for Rh(-)mother after delivered a Rh(+)baby(within 72h)Good perinatal careSleep well,Sleep well,Baby!Baby!