Hyaline membrane disease
This presentation is the property of its rightful owner.
Sponsored Links
1 / 35

Hyaline membrane disease PowerPoint PPT Presentation


  • 95 Views
  • Uploaded on
  • Presentation posted in: General

William 2001. Hyaline membrane disease. Hyaline membrane disease Retinopathy of prematurity Respiratory distress in term infants Meconium aspiration. Fetal lungs at birth : ↓ fluid ( expressed or absorbed ) ↑ air ↑ blood Type II pneumocytes  surfactant

Download Presentation

Hyaline membrane disease

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


William 2001

William 2001

Hyaline membrane disease


Hyaline membrane disease

  • Hyaline membrane disease

  • Retinopathy of prematurity

  • Respiratory distress in term

    infants

  • Meconium aspiration


Hyaline membrane disease

Fetal lungs at birth :

  • ↓ fluid ( expressed or absorbed )

  • ↑ air

  • ↑ blood

    Type II pneumocytes surfactant

    Surfactant  ↓ surface tension

    ↓ surfactant  collapse of the alveoli at

    the end of expiration + hyaline membrane

    in alveoli and distal bronchioles

Hyaline membrane disease


Hyaline membrane disease

Corticosteroid therapy  ↓ HMD

HMD ↑ in  boys – blacks

Preeclampsia and PROM  no ↓ HMD

Clinical picture:

  • Tachypnea

  • Retraction of chest wall

  • Grunting – flaring

    Progressive shunting of blood through


Hyaline membrane disease

nonventilated areas 

  • Hypoxemia

  • Acidosis ( respiratory – metabolic )

  • Hypotension ( systemic – peripheral )

    X ray:

  • Diffuse reticulogranular infiltrate

  • Air – filled tracheobronchial tree

    ( air bronchogram )


Hyaline membrane disease

Other causes of respiratory insufficiency:

  • Sepsis

  • Meconium aspiration

  • Pneumonia

  • Pneumothorax

  • Diaphragmatic hernia

  • Persistent fetal circulation

  • HF


Hyaline membrane disease

Common causes of cardiac

decompensation in neonates:

  • PDA

  • CHD

    Pathology:

    Hypotension and hypoxemia 

    Epithelial tissue necrosis 

    Pulmonary HTN + relative R to L shunt


Hyaline membrane disease

O2 therapy 

  • damage to the lungs & retina

  • reversal of the shunt

    Hyaline membrane =

  • fibrin rich protein

  • cellular debris

  • necrotic tissue below it

    Gross appearance = liver - like


Hyaline membrane disease

Histologically:

  • Collapsed alveoli

  • Some widely dilated alveoli

  • Vacuolated duct epithelium

    Treatment:

  • ICU

  • If arterial PO2 < 40mmHg  give the

    lowest level sufficient to treat hypoxia

    and acidosis = PO2 50 – 70 mmHg


Hyaline membrane disease

Continuous +ve airway pressure (CPAP):

- Prevent alveolar collapse↓mortality

- Disadvantages:

  • ↓ VR

  • Possible barotrauma

  • Brochopulmonary dysplasia

    High frequency oscillatory ventilation

    ± NO for severe pulmonary HTN:

     Pulmonary VD with no systemic VD


Hyaline membrane disease

Surfactant:

1st report in 1980 by Fujiwara

Helpful in LBW = 500 – 750 gm

= 23 – 26 weeks

↓ mortality by 20 – 25%

It’s rule in older fetuses  debate

Types:

Biological (animal-human)–synthetic


Hyaline membrane disease

Complications :

  • Bronchopulmonary dysplasia

  • Pulmonary HTN

  • Retinopathy

    Bronchopulmonary dysplasia:

    = O2 toxicity lung disease

    Alveolar and bronchiolar epithelial

    damage  hypoxia + hypercarbia

    + O2 dependence  peribronchial

    and interstitial fibrosis  P HTN


Hyaline membrane disease

Prevention:

Avoidelective preterm labor:

  • Estimate GA

  • Confirm lung maturity

    Then weigh risks of maternal disease

    against risks of prematurity

    Amniocentesis to confirm fetal lung maturity:


Tests of lung maturity

1 – Lecithin-to-sphingomyelin ratio:

< 34 weeks L/S R = < 2

≥ 34 weeks L/S R = ≥ 2

RDS ↑ if L/S R = < 2

↓ if L/S R = ≥ 2

Blood contamination  ↑↓ L/S

Meconium  ↓L/S

Tests of lung maturity


Hyaline membrane disease

Studies on L/S Ratio :

  • ↓ L/S R is more predictive of the need

    for ventilatory support # ↓ GA & BW

  • Some maternal diseases  RDS with

    L/S R ≥ 2 espatially DM

  • Metabolic and respiratory acidosis in

    severe DM  RDS

  • Lung maturation not delayed in DM

  • Delayed lung maturation is associated

    with poor glucose control


Hyaline membrane disease

  • No RDS in blacks if L/S ratio is > 1 ½

    2 – Phosphatidylglycerol:

  • Enhance surface active properties

  • Not detected in blood, meconium or

    vaginal secretions

  • For more assurance that RDS will not develop

  • It’s absent does not mean that RDS

    will develop after delivery

  • Some do not deliver DM except if it is +ve


Hyaline membrane disease

3 – TDx– FLM:

- Measures surfactant/albumen R

- rapid  ½ hour

- ≥ 50  100% lung maturity

- Equal or superior to L/S R, shake

and phosphatidylglycerol tests

- Some use it as 1st line before L/S

4 - Shake test:

1972


Hyaline membrane disease

Contamination↑ false –ve results

Used as screening test by some

5 – Lumadex – FSI: reliable

6 -- Fluorescent polarization:

reliable simple

rapid expensive

7 – AF absorbance at 650 - nm

wavelength = L/S R


Hyaline membrane disease

8 - Lamellar body count:

Simple – rapid – accurate

≥ 35000/mL = 100% lung mature

9 - Dipalmitoylphosphatidylcholine

( DPPC test ):

sensitivity = 100%

specificity = 96%


Retinopathy of prematurity

< 1950 = largest single cause of blindness

> 1950 = ↓ due to avoiding ↑ O2 therapy

- The retina vascularizes centrifugally from

the optic nerve starting at the 4th month

until after birth . During this period it is

easily damaged

- ↑ O2  mostly damage the temporal

portion of the retina

Retinopathy of prematurity


Hyaline membrane disease

- ↑ O2  severe VC  endothelial damage

and vessel obliteration  hypoxia

- ↓ O2  hypoxia  neovascularization

 Hg and proteinaceous material

 adhesions  retinal detachment

Prevention:

- ↓ O2 to 40% of the inhaled air ( may not

be sufficient for very immature fetus )

- Large dose of vit E ( controversial )


Respiratory distress in the term infant

Much less frequent

Causes:

  • Sepsis

  • Meconium aspiration

  • Intrauterine pneumonia

  • Persistent pulmonary HTN

  • Pulmonary Hg

    Sepsis septicemia mostly due to

    group - B streptococcus disease

Respiratory distress in the term infant


Hyaline membrane disease

Meconium is usually associated with:

  • Oligohydramnios

  • Uteroplacental insufficiency

  • Fetal distress

    Persistent pulmonary HTN may follow:

  • Elective CS

  • Premature closure of ductus

    arteriosus


Hyaline membrane disease

Treatment:

Similar to hyaline membrane disease:

High frequency oscillatory ventilation +

nitric oxide inhalation in severe pulmonary

HTN  pulmonary VD with no systemic VD

 ↓ fetal death

 ↓ need for extracorporeal

membrane oxygenation ( ECMO )

But not useful < 34 weeks


Meconium aspiration

Severe pulmonary disease characterized

by:

Chemical pneumonitis

Mechanical obstruction

Resulting from:

Peripartum inhalation of meconium

- stained AF inflammation + hypoxia

Free fatty acids  remove the surfactant

In severe cases  pulmonary HTN  death

or long – term neurological sequelae

Meconium aspiration


Hyaline membrane disease

= % 20 of pregnancies at term

In the past MA = fetal distress

Now = normal GIT maturation

or vagalstimulation by UCcompression

But still considered a marker of:

adverse perinataloutcome

In healthy fetuses + normal AFV  cleared

Not cleared mostly in thick meconium

with: Postterm - FGR


Hyaline membrane disease

Risk factors:

  • ↓ AFV

  • Cord compression

  • Uteroplacentalinsufficiancy

    MA ↑ in:

  • Thick meconium

  • Abnormal FHR

    Transient episodes of cord compression

    may  MA in cases of oligohydramnios


Hyaline membrane disease

MA can not be predicted:

- = 20% of normal pregnancies

- CS for meconium and abnormal

FHR  no alteration of % of

meconium beneath the cords

- Aggressive peripartum airway

management did not prevent

fetal death


Hyaline membrane disease

Prevention:

Carson 1976 

- Oropharyngeal suction of the infant

before delivery of the chest

- Laryngoscope visualization:

If meconium is visualized 

additional suctioning of the trachea


Hyaline membrane disease

Studies:

- This procedure  2.1% MA = still occur

= not caused by delivery

- Routine tracheal suction of nondepressed

infants with meconium stained AF 

↑ morbidity # no suction

- MA is caused by chronic antenatal insult

 abnormal muscularizationof interacinar arteries

- MAin baboon model no deathor long –

term neurological sequence


Hyaline membrane disease

- MA is caused by chronic fetal

asphyxia  pathological changes:

  • Pulmonary vascular damage

  • Persistent fetal circulation

  • Pulmonary HTN

    - Markers of acute asphyxia are not ↑:

    pH - lactates - hypoxanthine

    - 1 Marker of chronic asphyxia is↑:

    erythropoietin


Hyaline membrane disease

Amnioinfusion:

Used toreliefvariable decelerations during labor:

  • ↓ VD& cord compression

  • ↓ MA & meconium below the cords

  • ↓ Operative delivery

  • Neonatal acidosis

    Useful for healthy fetus with thick meconium

    Not useful for chronic asphyxia


Hyaline membrane disease

Management of MA:

- Suction before delivery of the shouldersby:

  • Suction bulb

  • DeLeetrapconnected to wall suction

    and not suctioned by mouth

    Study:

    - Both are equally efficacious

    - Carful suction  5% MA in moderate

    to thick meconium


Hyaline membrane disease

- If the infantis depressed or + thick

particulate meconium:

Suction under visualization

Intubation + tracheal suction

Stomach suction

- In thin meconium  tracheal suction

is controversial

- Efficacy is unknown  skillful suction

carry little risk of harm


  • Login