Case Conference

Maria Victoria B. Pertubal M.D.PGY1

Case

• 33 weeker preterm male• NSVD• APGAR 9/9• BW 1990g

• Admitted to NICU for prematurity and LBW

• labored breathing

What are your considerations?• Respiratory causes:– Respiratory Distress Syndrome (RDS) aka Hyaline

Membrane Disease (HMD)– Transient tachypnea of the Newborn (TTN)– Pneumonia– Air leak / pneumothorax– Persistent pulmonary hypertension– aspiration syndromes (meconium, amniotic fluid), – congenital anomalies such as cystic adenomatoid

malformation, pulmonary lymphangiectasia, diaphragmatic hernia, and lobar emphysema

Other differential diagnoses?

• Cardiac causes:– Cyanotic congenital heart disease • 5T’s

• Other Systemic disorders:– Hypothermia– Hypoglycemia– Anemia ; polycythemia– Metabolic acidosis

Initial Work-up

• Chest X-ray• ABG• CBC, Blood culture• BMP, glucose

CXR

• C

Hospital course:

• 1st hospital day : NCPAP, FiO2 25-35% – O2 sats 93-95%

• 2nd hospital day: NCPAP, FiO2 35-50%– SC/IC retractions, O2 sats 88-92%– Repeat CXR, ABG

Respiratory Distress Syndrome

aka. Hyaline Membrane disease (HMD)

Incidence• primarily in premature infants

• male > females• white infants• inversely related to gestational age and

birthweight. – 60-80% of <28 wk of gestational age– 15-30% of 32 - 36 weekers, – rarely in those >37 wk.

Other Risk factors

• maternal diabetes• multiple births• cesarean delivery• precipitous delivery• asphyxia, • cold stress• maternal history of previously affected

infants.

Reduced risk in..

• pregnancies with chronic or pregnancy-associated hypertension

• maternal heroin use• prolonged rupture of membranes• antenatal corticosteroid prophylaxis.

Etiology and Pathophysiologyof RDS:

Surfactant deficiency (decreased production and secretion)

SurFactant Facts

Nelson Pediatrics Figure 95-2 (From Jobe AH: Fetal lung development, tests for maturation, induction of maturation, and treatment. In Creasy RK, Resnick R, editors: Maternal-fetal medicine: principles and practice, ed 3, Philadelphia, 1994, WB Saunders.)

• 90% Lipids (Phospholipids)• 10% Proteins (4 Surfactant specific)

-A,-B,-C,-D

• produced by type 2 alveolar cells

The Premature Lung

• Both decreased in quantity and quality of surfactant

• LESS QUALITY due to:– Less protein content –PhosphatidylINOsitol > PhosphatidylGLYcerol

Figure 95-4 Nelson pediatrics

Clinical Manifestations

• Tachypnea• Nasal flaring, • Expiratory grunting• Intercostal, subxiphoid, and subcostal retractions, • Cyanosis or pallor• breath sounds are decreased • diminished peripheral pulses. • urine output often low in the first 24 to 48 hours

and peripheral edema

CXR: diffuse reticulogranular ground-glass appearance with airbronchogram

A. Severe RDS B. Moderate RDS

Other Laboratory findings

• Arterial blood gas – hypoxemia that responds to supplemental

oxygen.– PCO2 initially is normal or slightly elevated, but

may increases as the disease worsens.

• hyponatremia

Management1. DELIVERY ROOM: Provide warmth, position

head, clear air, stimulate baby.

2. Assisted ventilation (MV, CPAP, NIPPV)

3. Surfactant therapy

4. Inhaled NO

5. Glucocorticoid (post-natal)

6. Other supportive care - Fluid status monitoring- Early nutrition

Surfactant therapy

• Types available- Survanta (Bovine); Curosurf(porcine); Infrasurf (Calf); Exosurf(synth)

• Indications: – Prophylactic therapy – immediately after birth– Early-rescue therapy – during the 1st few hours after

birth. • AAP recommends to give when the diagnosis of RDS is

established; – Continued therapy - clinical evidence of persistent

disease

Ventilatory support• to improve oxygenation and elimination of CO2 w/o

causing pulmonary injury/toxicity

• Criteria for mechanical ventilation – Respiratory acidosis- pH <7.20, PaCO2 >60 mm Hg– Hypoxia- PaO2 <60 mm Hg oxygen, O2sats <85%

despite supplementation of 70 % on nasal CPAP– Severe apnea

• CPAP, HFV, NIPPV- alternative to mechanical ventilation

Other treatment options: (controversial)

• Inhaled Nitric oxide– Mosty benefits or late preterm infants with

persistent pulmonary hypertension through: • reduced lung inflammation, • improved surfactant function, • Slows down hyperoxic lung injury, • promotes lung growth

– Not commonly used due to cost

• Postnatal glucocorticoids– given in the first day of life– improves pulmonary and circulatory function and

decreases the incidence of BPD– Limitations of use:• short-term complications: intestinal perforation,

metabolic instability; • long-term abnormal neurodevelopmental outcomes

Other treatment options: (controversial)

Prevention

• Avoidance of unnecessary or poorly timed cesarean section,

• appropriate management of high-risk pregnancy and labor

• Antenatal corticosteroids for all women in preterm labor (24-34 wk of gestation) who are likely to deliver a fetus within 1 wk

Complications of RDS:

• Endotracheal tube complications• Bronchopulmonary dysplasia (BPD)• Pulmonary air leak – Pneumothorax– Pneumomediastinum– Pulmonary interstitial emphysema (PIE)

pneumothorax

Pneumothorax, Left

case

pneumomediastinum

pneumomediastinum

Pulmonary interstitial emphysema

Pulm Interstitial empysema PneumomediastinumpneumopericardiumSubcutaneous emphysema

Courtesy of Gerardo Cabrera-Meza, MD

References:• Carlo, W. Respiratory Distress Syndrome (Hyaline Membrane

Disease) Nelson Textbook of Pediatrics. 2011• Welty, Stephen. Treatment and complications of respiratory

distress syndrome in preterm infants. Uptodate may2011– http://www.uptodate.com.elibrary.einstein.yu.edu/contents/treatment-and-complications-of-

respiratory-distress-syndrome-in-preterm-infants?source=see_link#H17

• Fernandes, Caraciolo. Pulmonary Air Leak in the Newborn. Uptodate. May 2011

<http://www.uptodate.com.elibrary.einstein.yu.edu/contents/treatment-and-complications-of-respiratory-distress-syndrome-in-preterm-infants?source=see_link#H25>

• <http://www.vanuatumed.net/MODULES/07_WomensChildrens/_N+P_WomensChildrens/139_Jackson/ISSUES/139_LI4_files/image001.jpg>

• Staporn Maung-In, M.D <http://www.med.cmu.ac.th/dept/pediatrics/06-interest-cases/ic-42/case42.HTM>