Approved by the Missouri Society for Respiratory Care for 1 CRCE
Authored by: Shawna Strickland, MEd, RRT-NPS, AE-C

Introduction

Just the Facts

• Approximately 3.5 million babies are born every year in the United States.
• Only 15% of the 5000 hospitals in the US have neonatal intensive care facilities.
• Ten percent of all newborns require life support in the delivery room or nursery.
• It is estimated that 5 million neonatal deaths occur worldwide, and 19% of those are attributed to birth asphyxia.

Factors Affecting the Newborn's Condition

• Gestational age
• Maternal history
• Medications given to/taken by the mother
• Intrapartum risk factors

Gestational Age

Why is it so important to determine the newborn's gestational age?

Because the lung develops in stages and is not able to sustain life until approximately the 24 th week of gestation.

 

Fetal Lung Development: Four Phases

Embryonic

• When: Through week 5
• What: lung bud forms, divides, continues to grow; divides into left and right mainstem bronchi
• Possible disorders: tracheal agenesis, tracheal-esophageal fistula

Pseudoglandular

• When: Weeks 5 through 16
• What: branching of bronchial tree, mucus glands appear, smooth muscle appears, closure of diaphragm
• Possible disorders: congenital lobar emphysema, congenital diaphragmatic hernia if closure delayed after the 8-10 th week.

Canalicular

• When: Weeks 17 through 24
• What: terminal bronchioles develop, capillary network begins to appear, alveolar epithelium differentiates into Types I and II cells. (Type II cells responsible for surfactant production)
• Possible disorders: lung function depends on degree of development

Terminal Sac

• When: Weeks 25-37
• What: Maturation of surfactant, alveolar-capillary membrane expands for better gas exchange. At 32 weeks, alveolar ducts open.  At 34 weeks, alveoli develop and cause lung size to rapidly increase.
• Possible disorders: Hyaline Membrane Disease

Lung Maturity

Surfactant

• is produced by Type II alveolar epithelial cells
• lines the internal surface area of the lung
• lowers surface tension by adsorbing to the surface and displacing water molecules
• is composed of phospholipid (lecithin), with small amounts of proteins and carbohydrates

Lung Maturity Tests: L/S Ratio

• Lecithin is the phospholipid that makes up the majority of the weight of surfactant.
• Sphingomyelin is a phospholipid mostly from fetal sources.
• Sphingomyelin levels exceed lecithin levels until the 26 th week, when lecithin levels begin to rise.
• Lecithin exceeds sphingomyelin at 32-36 weeks.
• L/S ratio > 2 indicates mature lungs .

Maternal History: What to ask?

Did she have prenatal care?

• If the mother was followed by an obstetrician or family physician during pregnancy, the chances of better nutrition and general care is greater.
• Also, the due date would be more accurate if the mother has had at least one ultrasound to assess gestational age of the fetus.

Is this her first pregnancy?

• If not, did she have any complications with other pregnancies?
• The risk of delivering a low-birth weight newborn increases with the number of previous premature births.

Is she pregnant with more than one baby at this time?

• Multiples are at a high risk of developing Hyaline Membrane Disease (HMD) because they are often born prematurely.

Does she have any pre-existing medical conditions?

Maternal medical conditions can impact the unborn fetus.  Some conditions and their effects:

• Diabetes: HMD, congenital heart defects
• Oligohydramnios (small amount of amniotic fluid): poor renal function
• Polyhydramnios (large amount of amniotic fluid): esophageal, gastrointestinal, CNS problems
• Maternal infection: pneumonia, sepsis

Is she currently taking medication of any kind (prescribed or illegal)?

• Some controlled/illegal substances taken by the mother can cause newborn depression.
• Barbituates (thiopental, phenobarbital)
• Narcotics (morphine, heroin)
• Tranquilizers (Lithium, Valium)
• Magnesium Sulfate (used to stop labor)
• Anesthetics and Analgesics

Has she used alcohol or tobacco during her pregnancy?

• The use of alcohol and/or tobacco during pregnancy can result in the newborn being born of low birth weight.

Intrapartum Risk Factors [1]

Emergency Cesarean section

• The absence of the "squeezing" motion on the thorax of the infant can promote retention of fetal lung fluid.

Premature labor

• Birth before the 37 th week of gestation is the greatest cause of neonatal morbidity and mortality. Prior preterm delivery increases the risk of subsequent preterm deliveries.

Meconium-stained amniotic fluid

• A term or post term infant that has been stressed due to delivery or a hypoxic event can pass the first bowel movement in utero.  The meconium mixes with the amniotic fluid and is transferred into the lungs during fetal breathing movements.  Upon delivery of the infant, some meconium may stay in the lungs and prevent adequate gas exchange.

Prolapsed cord

• The umbilical cord is delivered (passed through the cervix) before the infant.  This compromises the blood flow to the infant due to the compression of the cord.

Placenta previa

• The placenta covers the cervical os, preventing the infant from passing through the cervix.  A Cesarean delivery is usually required.  This is usually associated with advanced maternal age, multiple gestation and prior Cesarean deliveries.

Placental abruption

• The placenta separates from the uterine wall before the infant is born.  This leads to bleeding from the infant.

Fetal Bradycardia

• Deceleration of the fetus' heart rate can indicate the impact of contractions or a more serious insult such as nuchal cord.

Newborn transition

Fetal Oxygenation

• The placenta provides oxygenated blood from the mother to the fetus. 
• Although the fetal lungs are expanded, the alveoli are filled with fluid.
• Instead of perfusing the lungs, the blood is shunted from the pulmonary artery to the aorta by way of the ductus arteriosus.  This shunt is caused by the constricted blood vessels in the fetal lungs.

At Birth

• The fluid that filled the alveoli is expelled during delivery or absorbed by lung tissue, and the alveoli expand with air with the first breath.
• An increase in systolic blood pressure occurs when the umbilical cord (containing the umbilical arteries and vein) is clamped.
• With exposure to oxygen, the blood vessels in the lungs relax, causing increased pulmonary blood flow and decreased blood flow across the ductus arteriosus.

Problems with transition

• Insufficient breathing:  fails to force fluid from the lungs.
• Systemic hypotension: caused by excessive blood loss, poor cardiac contractility or bradycardia from hypoxia.
• Persistent pulmonary hypertension (sustained constriction of the blood vessels in the lungs).

Postnatal Assessment: Apgar Scoring

The Apgar score assesses five criteria:

• Color (Appearance)
• Heart rate (Pulse)
• Reflex irritability (Grimace)
• Muscle tone (Activity)
• Respirations

Each criteria has a maximum of 2 points.  The maximum score for an infant is 10.

Apgar Scoring Table

APGAR Scoring

• Scores done at 1 minute to identify who needs immediate intervention.
• Scores taken again at 5 minutes to assess recovery from depression or a subsequent turn for the worse.
• Remember that resuscitation takes precedence over determining score.

Neonatal Resuscitation Program [2] [3]

NRP is based on the American Academy of Pediatrics and American Heart Association's International Guidelines for Emergency Cardiovascular Care of the Newborn.

NRP is dedicated to providing education and training to health care providers working in the delivery rooms and nurseries.

Updated guidelines in 2005

• Why? Technology is changing and we need to keep up!
• The new guidelines focus more on ethics, premature births and special needs such as blended gas mixtures and additionaltemperature control devices.

Neonatal Resuscitation:

The ABCD's of Resuscitation:

• Airway
  • Provide warmth.  A radiant warmer should be warm and available for all deliveries.
  • Position the head and clear the airway as necessary.
  • Dry and stimulate the baby to breathe.
  • Evaluate respirations, heart rate and color; give oxygen as needed.
• Breathing
  • If the baby is apneic, or heart rate is less than 100 bpm:
  • Provide positive pressure ventilation with a resuscitation bag and 100% oxygen.
  • The resuscitation mask should be chosen based on the size of the infant.  The mask should fit from the bridge of the nose to the chin, but not covering the eyes.  A good seal with the mask is necessary for resuscitation.
• Circulation
  • If the heart rate is less than 60 bpm:
  • Give chest compressions as you continue to provide positive pressure ventilation with 100% oxygen.
  • Give chest compressions at a rate of 3 compressions to every breath, resulting in 90 compressions per minute, and 30 ventilations per minute.
• Drugs
  If the heart rate is less than 60 bpm after 30 seconds of assisted ventilation and another 30 seconds of chest compressions and assisted ventilation:
  • Administer epinephrine while continuing chest compressions and assisted ventilation.
    (Endotracheal intubation should be considered as prolonged ventilation becomes apparent)

Assess, Assess, Assess!

• Assess the infant every 30 seconds to determine effectiveness of resuscitation.
• If the heart rate rises above 60, discontinue compressions.
• If the heart rate rises above 100, discontinue compressions and gradually discontinue ventilation, based on the infant's spontaneous respirations.

Proper assessment of heart rate
Two ways to assess the heart rate of the newborn:

• Palpating the base of the umbilical cord
• Listening to the chest with a stethoscope

Cardiopulmonary Resuscitation

• Proper placement of the resuscitation bag and mask on the infant's face
• Proper placement for fingers on the infant's chest for chest compressions

Intubation and the Neonate's Airway: A Closer Look.

Intubation Equipment:

• Laryngoscope and blade (size 00, 0 or 1)
• Endotracheal tubes (sizes 2.5-4.0)
• Suction equipment (14F catheter for suctioning of meconium)
• Manual resuscitator and reservoir
• 100% oxygen source (an oxygen blender and pulse oximeter is now recommended for use with preterm infants)
• Stylet (optional)
• End tidal carbon dioxide detector (no longer an optional piece of equipment)

How do I decide what size tube to use?

• The endotracheal tube is chosen based on the baby's birth weight.

• The primary methods of proper ETT placement are an increasing heart rate and carbon dioxide detection.
• Tube placement is also determined by the baby's birth weight.
• Formula: add six to the baby's weight (in kg).
• Example: 2 kg baby
  6 + 2 = 8 cm at gums

Special Considerations

What if PPV isn't making the chest doesn't rise?

• Think about a blocked airway (either position of the infant or meconium/mucus plugs) or impaired lung function

What if the baby is still cyanotic or bradycardic?

• Think about congenital heart disease

What if the baby won't breathe on his own?

• Think about brain injury or maternal sedation

Things to remember: what can happen in post-resuscitation

• Pneumonia
• Metabolic acidosis
• Hypotension
• Fluid imbalance
• Seizures or apnea
• Hypoglycemia
• Feeding problems
• Temperature instability

Things to remember about premature infants:

• Make sure you keep them warm (radiant warmers, plastic wrap, heating pads)
• Consider surfactant administration
• Decrease chance of brain injury (avoid swings in blood pressure and PaO 2 )
• Prevent infection (maintain clean environment, use sterile technique with suctioning and line placement)

NRP 2005 Guidelines: Discontinuation of resuscitation [4]

• "If there is no heart rate after 10 minutes of complete and adequate resuscitation efforts, and there is no evidence of other causes of newborn compromise, discontinuation of efforts may be appropriate."

Examples of Newborn Assessment: Practical Application

Newborn Assessment: The Healthy Baby

Key assessment points:

• Completely pink
• Good muscle tone
• Crying
• Assess heart rate and respirations
• No intervention needed  

Newborn Assessment: The Baby with Acrocyanosis

Key assessment points:

• Body is pink, extremities are blue
• Supplemental oxygen is not needed for these infants

Newborn Assessment: The Cyanotic Baby

Key assessment points:

• Crying
• Some muscle tone
• Body and extremities are blue
• Supplemental oxygen, possibly assisted ventilation needed

Newborn Assessment: The Pale Baby

Key assessment points:

• Not crying
• Baby is pale
• Little response to stimulation
• Little muscle tone

(There was a history of placenta previa with this infant; volume expanders are needed.)

Newborn Assessment: The Meconium Stained Baby   

Key assessment points:

• Cyanotic
• Poor tone and respiratory effort
• Covered with meconium
• Requires endotracheal intubation and suctioning

Newborn Assessment: The Preterm Baby

Key assessment points:

• Cyanotic
• Poor muscle tone
• Poor respiratory effort
• Requires assisted ventilation

*All photographs courtesy of the Neonatal Resuscitation Program, 4^th Edition.

[1] Khabbaz AY, Quirk JG. Antenatal assessment and high-risk delivery, in Czervinske and Barnhardt (eds) Perinatal and Pediatric Respiratory Care 2 nd edition.  (2003) p. 20-31.

[2] Bloom RS, Cropley C, AHA/AAP NRP Steering Committee. Textbook of Neonatal Resuscitation, 4 th Ed. American Heart Association, 2000.

[3] AHA/AAP NRP Steering Committee. Textbook of Neonatal Resuscitation, 5 th Ed. American Heart Association, 2005.

[4] AHA/AAP NRP Steering Committee. Textbook of Neonatal Resuscitation, 5 th Ed. American Heart Association, 2005.

Click here if you are ready for the post-test

Back to the Top