Maria Victoria B. Pertubal M.D. PGY1 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 Cardiac causes are usually have milder respiratory distress. On CXR, you don’t see the typical findings seen in rds (reticulo-granular ground glass appearance and airbronchogram. Hyperoxia and surfactant administration don’t help

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 male > females primarily in premature infants 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. Synthesis of surfactant depends in part on normal pH, temperature, and perfusion

Reduced risk in.. pregnancies with chronic or pregnancy-associated hypertension maternal heroin use prolonged rupture of membranes antenatal corticosteroid prophylaxis.

Etiology and Pathophysiology of RDS: Surfactant deficiency (decreased production and secretion)

SurFactant Facts 90% Lipids (Phospholipids) 10% Proteins (4 Surfactant specific) -A,-B,-C,-D produced by type 2 alveolar cells 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.)

The Premature Lung Both decreased in quantity and quality of surfactant LESS QUALITY due to: Less protein content PhosphatidylINOsitol > PhosphatidylGLYcerol PG is used as a marker for fetal lung maturity at 35 weeks AOG

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 Grunting - results from exhalation through a partially closed glottis Retractions – because chest wall is highly compliant Cyanosis – due to R to L shunting

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 Hyponatremia develops from water retention, treat with fluid restriction

Management 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 Fluid status must be carefully monitored as excessive fluid increases the risk of patent ductus arteriosus, necrotizing enterocolitis (NEC), and BPD Nutrition to support growth and development. Prevent protein breakdown

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

Other treatment options: (controversial) 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

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 Pneumomediastinum pneumopericardium Subcutaneous 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>