Prematurity

5,425 views

Published on

Published in: Education, Health & Medicine
1 Comment
18 Likes
Statistics
Notes
No Downloads
Views
Total views
5,425
On SlideShare
0
From Embeds
0
Number of Embeds
30
Actions
Shares
0
Downloads
793
Comments
1
Likes
18
Embeds 0
No embeds

No notes for slide
  • Ultrasound estimation of gestational age - 14-20wks:  10-11dys - 20-28wks:  14dys - 29-40wks:  21dys Direct ophthalmoscopy of the lens - Before 27 weeks: cornea too opaque to allow visualisation - After 34 weeks: atrophy of vessels of lens occurs Reliable to  2 weeks Pupils must be dilated Assessment must be performed within 48 hrs of birth before the vessels atrophy Grading system
  • Prematurity

    1. 1. Prematurity Dr Varsha Atul ShahDept of Neonatal and Developmental Medicine Singapore General Hospital
    2. 2. Extremes of Birth WeightNeonatalHypoglycaemia Prematurity
    3. 3. PretermDefinition: < 37 completed Gestational weeks • Gestational age assessment – Obstetric information • LMP, ultrasound, others (quickening, etc) – Newborn information • Neurological, physical – Dubowitz Score, New Ballard Score • Direct ophthalmoscopy of the lens
    4. 4. Dubowitz Score
    5. 5. New Ballard Score
    6. 6. Assessment of maturity byexamination of anteriorvascular capsule of the lens Hittner et al
    7. 7. IncidenceSingapore• Preterm births: 5-8 % of all births
    8. 8. Associated Factors• Maternal – Low socioeconomic status – Lack of prenatal care – Substance abuse, smoking – Maternal age < 16yrs or > 35yrs – Maternal illness e.g. renal, heart, lung, HPT, DM, etc – Multiple gestation – Prior preterm delivery – Obstetric factors e.g. uterine malformations, cervical incompetence, polyhydramnios, premature rupture of membranes, infection (e.g. chorioamnionitis), placenta praevia, abruptio, etc – Abdominal trauma / surgery• Foetal – Foetal distress, IUGR, etc
    9. 9. Problems of Prematurity• Related to difficulty in extrauterine adaptation due to immaturity of organ systems• Degree of immaturity – Appearance, behaviour, problems, clinical course – Mildly preterm (35 - 36 wks) – Moderately preterm (32 - 34 wks) – Severely preterm (< 32 wks)
    10. 10. Management• Prevention – Obstetric Mx: maternal illness, infection – Inhibition of preterm labour – Steroids to facilitate lung maturationProblems & Management:• Initial, acute• Long term
    11. 11. Initial Problems & Management Immediate postnatal management Temperature regulation Respiratory Neurologic Cardiovascular Haematologic Gastrointestinal & Nutritional Metabolic Renal Fluid & electrolyte Infection Ophthalmologic Osteopenia Liver Surgical conditions Immunisation Social
    12. 12. Immediate Postnatal Management• Delivery – Appropriately equipped & staffed• Resuscitation & stabilisation
    13. 13. Temperature Regulation• Poor temperature control – Hypothermia, hyperthermia 1. Immature heat regulatory centre 2. Impaired heat production ∀ ↓ brown fat, poor muscular activity, poor 02 consumption 3. Increased heat loss ∀ ↓ subcutaneous fat, ↑ surface area (large surface area to body weight, extended position)
    14. 14. Management• Achieve neutral thermal zone i.e. environmental T0 at which O2 consumption is minimal yet sufficient to maintain body T0• Yet exposed to facilitate observation• Heat shield, plastic wrap, cap• Overhead radiant warmer – Infant accessibility, rapid T0 response• Closed incubator ↓ insensible H2O loss, barrier to infection
    15. 15. Overhead radiant warmer Closed incubator
    16. 16. Respiratory• Asphyxia – Poor adaptation to air breathing – Perinatal depression at delivery• Periodic breathing - jerky, irregular• Apnoea – Immature respiratory centre – Small nasal passages & airways – Weak respiratory muscles – Compliant thoracic cage
    17. 17. • Respiratory distress syndrome (HMD)• Aspiration pneumonia – Regurgitate easily – Uncoordinate suck & swallow – Weak gag, cough reflex• Chronic lung disease – Acute & continued lung injury (surfactant deficiency, pulmonary oedema, O2 exposure, mechanical ventilation, inflammation) with abnormal repair• Subglottic stenosis
    18. 18. Hyaline membrane disease Subcostal retractions
    19. 19. Management• Assisted ventilation – Tracheal intubation & mechanical ventilation – CPAP (Continuous Positive Airway Pressure) – O2 therapy• Medication – Surfactant – Aminophylline, caffeine – Diuretics, steroids
    20. 20. IntubatedCPAP Intranasal oxygen
    21. 21. Neurologic• Hypotonic• Perinatal depression• Cerebral ischaemia & intracranial haemorrhage – Germinal layer vascular with little supporting tissue – Prone to hypoxia – Impaired ability to regulate cerebral blood flow
    22. 22. Cardiovascular• Hypotension – Hypovolaemia, cardiac dysfunction, vasodilation (sepsis)Management – Fluid resuscitation – Inotropes
    23. 23. • Patent ductus arteriosus (PDA), CCFManagement – Usually only requires conservative Mx • Adequate oxygenation, fluid restriction – Medical Mx: Prostaglandin antagonist (indomethacin, ibuprofen) – Surgical Mx: PDA ligation
    24. 24. Haematologic• Anaemia – Iatrogenic losses – Haemorrhage, haemolysis – Inadequate productionManagement• Minimizing blood loss• Transfusion• Iron supplement• Misc: erythropoietin
    25. 25. ∀ ↑ susceptibility to hyperbilirubinaemia & kernicterus 1. ↑ bilirubin production ∀ ↓ rbc lifespan, ↑ haemorrhage & haemolysis 2. ↓ bilirubin excretion • impaired uptake & conjugation by liver, ↓ excretion via bile 3. ↓ bilirubin binding capacity ∀ ↓ serum albumin, hypothermia, acidosis 4. Permeable blood brain barrierManagement – Careful monitoring of bilirubin levels – Phototherapy – Exchange transfusion
    26. 26. Phototherapy, preterm infant, on CPAP, incubator
    27. 27. Gastrointestinal & Nutritional• Many preterm infants are unable to suck & swallow effectively – Coordination of suck with swallow only occurs ≥ ~ 32 - 34 wks• Feed intolerance ↓ intestinal motility• Necrotising enterocolitis
    28. 28. NECGross abdominal distensionShiny, oedematous, anteriorabdominal wall with distended vessels
    29. 29. Management – Specific attention to type (expressed breast milk & human milk fortifiers, preterm formula), amount & route of feeding – Gavage feeding – Parenteral nutrition – Multivitamin
    30. 30. Long line for TPN Tube feeding
    31. 31. Metabolic• Glucose (hypoglycaemia)• Calcium (hypocalcaemia)
    32. 32. Renal• Immature kidneys – Low GFR & inability to handle water, solute & acid loads – Drug dosage adjusted
    33. 33. Fluid & ElectrolyteFluid & electrolyte management difficult:• High insensible H2O losses – Skin loss, ventilation• Renal function• Aim – Normal glucose, electrolyte & fluid balance
    34. 34. Infection• Increased susceptibility 1. ↓ resistance – Impaired humoral & cellular response – Skin barrier 2. ↑ opportunity for infection – Natural defense bypassed - lines, procedures (e.g. Staphylococcal infection) – Prolonged hospitalisation, with other infants – Use of antibiotics – Nosocomial infection, fungal infection
    35. 35. Increased risk for nosocomialinfection
    36. 36. Ophthalmologic• Retinopathy of prematurity – Disorder of developing retinal vasculature Osteopenia• Deficiency of calcium, phosphate & vit D
    37. 37. Liver• Cholestatic jaundice – TPN, infection Surgical Conditions• Inguinal hernia
    38. 38. Immunisation• Immunised according to chronological age• No contraindication in infants with stable neurologic condition
    39. 39. Social• Financial• Psychosocial & Emotional
    40. 40. Mortality RatesGestational Age Mortality• > 30wks < 5%• 27 - 30wks 5 - 10%• 25 - 26wks 10 - 50%• 23 - 24wks 50 - 90%• < 23wks > 97%
    41. 41. Survival RatesBirth Weight Survival• < 1000g 80%• < 1500g 90%• > 1500g 99%
    42. 42. Long Term Problems & Management
    43. 43. Long Term Problems• Preterm infants are vulnerable to wide spectrum of morbidity• Severe impairment occurs in a small population• Prevalence of lesser morbidities less clearly defined
    44. 44. Developmental Disability• Major handicaps – Cerebral palsy, mental retardation
    45. 45. • Sensory impairments • Hearing loss, visual impairment• Minimal cerebral dysfunction – Language disorders, learning disability, hyperactivity, attention deficits, behavioural disorders
    46. 46. Medical Problems• Chronic lung disease – Increased severity respiratory infections• Hydrocephalus, epilepsy• Poor growth• Increased rates of postneonatal illness & rehospitalisation• SIDS
    47. 47. Social• Increased risk of child abuse & neglect• Financial• Psychosocial & Emotional• Marital discord• Parent support groups• Light Weight Club• Club Rainbow
    48. 48. Long Term Disability RatesBW CP MR Sensory impr• < 1500g 5 - 15% 5 - 8% 0.5 - 6%• < 1000g 8 - 15% 8 - 15% 4 - 12%• < 750 - 800g 3 - 14% 3 - 28% 4 - 15%
    49. 49. Management• Multidisciplinary team – Neonatologists – Nurses – Therapists – Psychologists – Medical specialists: ophthalmologist, otolaryngologist, cardiologist, paediatric surgeon, plastic surgeon – Medical social worker
    50. 50. Extremes of Birth WeightNeonatalHypoglycaemia Prematurity

    ×