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CHAPTER 4 Care at Birth
Time from onset of asphyxia (min)
(beats/min)
respirations
Secondary or
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TABLE
4.1
BODY STRUCTURE FETAL FUNCTION EXTRAUTERINE FUNCTION
Aorta Carries oxygenated blood from left ventricle and
Ductus venosus Shunts most of the oxygenated blood from
Foramen ovale Connects right and left atria; permits oxygen-
Ductus arteriosus Shunts blood from pulmonary artery directly
Umbilical arteries and vein Carry blood to and from placenta, the organ of
Lungs Distended with fluid; minimal pulmonary
COMPARISON OF VASCULAR AND PULMONARY FUNCTIONS BEFORE AND AFTER BIRTH
Carries oxygenated blood from left ventricle into
deoxygenated blood from pulmonary arteries to
fetal organs and placenta
placenta to inferior vena cava
ated blood from right atrium to bypass right
ventricle and pulmonary circuit and go directly
into left atrium
into aorta
respiration before birth
circulation; fetal respiratory movements
systemic circulation
Disappears within 2 weeks after birth; becomes
ligamentum venosum
Functionally closes soon after birth; anatomi-
cally seals during childhood
Functionally closes soon after birth; eventually
becomes ligamentum arteriosum
Clamped at birth, obliterating placental connec-
tions; become ligaments
Expanded and aerated; pulmonary circulation
allows CO2 and O2 exchange; organ of
respiration
69
terminal apnea
Primary
apnea
Gasps
(per min)
Heart rate
Arterial
pressure
(mm Hg)
FIGURE 4.2 Changes in physiologic parameters during asphyxiation and
resuscitation of rhesus monkey fetus at birth. (From Dawes GS. Foetal and
Neonatal Physiology: A Comparative Study of the Changes at Birth. St. Louis:
Mosby; 1968.)
6
4
2
0
200
150
100
50
60
40
20
0
0510
Last
Onset of
gasp
gasping
Asphyxia Resuscitation
Regular
15 20
beats/min and may be hypotonic. Thus, any infant
who is apneic at delivery must be assumed to
be in secondary apnea, and intervention should
begin immediately.
The longer the initiation of ventilation is delayed
after an infant’s last gasp in secondary apnea, the
longer the time necessary during resuscitation for
the return of the infant’s spontaneous respiration.
For every 1-minute delay, the time to the first
gasp increases by about 2 minutes, and the time
to the onset of spontaneous breathing is prolonged by more than 4 minutes.17 In the absence
of effective resuscitation after delivery, apnea and
decreased cardiac output result in progressive biochemical deterioration.
17
Severe fetal and neonatal asphyxia impair the
physiologic transitions to extrauterine life. The
normally high fetal pulmonary vascular resistance
may not decrease in the presence of pulmonary
hypoexpansion, persistent acidosis, and hypoxemia.
As part of persistent pulmonary hypertension of
the newborn, pulmonary blood flow and oxygen
transfer are impeded, perpetuating hypoxemia, and
normal closure of fetal shunts is delayed.68 This
results in persistent right-to-left shunting through
the ductus arteriosus and foramen ovale. Lung fluid
clearance also may be delayed because of poor lung
UNIT TWO Support of the Neonate70
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inflation or pulmonary hypoperfusion and hypoxemia. In addition, intraalveolar fluid may accumulate
as a result of leakage from damaged pulmonary
capillaries, resulting in pulmonary edema. With
worsening hypoxemia and acidosis, myocardial
function begins to fail, cardiac output falls, and
systemic perfusion decreases to the brain, kidney, and intestine, setting the stage for postasphyxial injury of these organs.
6
CLAMPING OF THE UMBILICAL
CORD
The optimal timing for cord clamping remains a
subject for debate, as it has been for decades, but
only recently has management of the umbilical
circulation been considered as part of stabilization or resuscitation of the newly born infant.58
The approach to the timing of cord clamping is variable worldwide; however, practice guidelines now
generally recommend a delay in cord clamping
of 1 to 3 minutes as the standard of care.
Maintaining placental circulation during the onset
of spontaneous respirations and inflation of the
lungs with air smooths the immediate cardiovascular
transition. Until pulmonary blood flow increases to
supply left ventricular preload, cardiac output and
systemic circulation depend on umbilical flow to
the right atrium and streaming across the foramen
ovale to the left atrium. Premature disruption of the
umbilical circulation can result in bradycardia and
fluctuations in systemic blood flow and pressure.
Placental transfusion, the amount of blood
that flows from the placenta to the infant at
birth before cord clamping or cessation of
cord pulsations, mediates blood volume as a
second major aspect of cardiovascular transition.27 A delay in clamping the cord for 30 to
120 seconds after birth facilitates the transfer
of an additional 30 to 150 mL of blood from
the placenta to the newborn, with most of
the transfer occurring in the first minute.31 The
maximal mean volume of placental transfusion
has been reported between 24 and 32 mL/kg
of body weight or an additional 30% to 40% of
blood volume in the first 3 minutes after birth.44
Immediate clamping of the umbilical cord after
delivery blocks the normal transfer of blood
from the placenta to the infant, resulting in
a deficit of as much as 25% of normal blood
5,87
11
volume.55 The quantity of blood transferred to
the infant appears to be influenced by the route
of delivery (vaginal, cesarean), the timing of cord
clamping, the initiation of respiration and cry, the
position of the newborn relative to the placenta
(gravity), manipulation of the cord (milking), and
the intensity of uterine contractions at the end
of the second stage of labor.
52,54,58
Experimental
evidence suggests that the onset of respirations is crucial in optimizing placental transfusion, and the physiologic sequence of delayed
cord clamping (DCC) is clamping after the
onset of respirations.
11
Studies conducted in term infants suggest that
early cord clamping (ECC), compared with DCC,
results in a greater risk of anemia in infancy.54
Late clamping acts as a low-cost intervention
to reduce anemia during the first 6 months
32,36
of life.
Despite concerns that the increase in
neonatal blood volume with DCC may result in
neonatal jaundice and polycythemia, randomized
trials in term infants have not substantiated an
increased need for special care related to these
diagnoses.44 In fact, a recent meta-analysis of
trials in preterm infants showed a reduction in
mortality with DCC.30 Several recent reviews
evaluating the potential benefits and risks of
late versus early cord clamping in the preterm
and term population summarize the evidence
that DCC after birth is beneficial to both
preterm and term infants.
31,44,54,65
In preterm
infants, these studies report benefits in terms of
improved physiologic stability and reduction in
the relative risk of intraventricular hemorrhage
and the need for transfusion.
Although there may be physiologic benefits
to delayed clamping, few studies have examined
the timing of cord clamping with respect to the
need for or response to resuscitation at birth.
In the event of fetal distress and neonatal depression, immediate clamping of the cord has usually
been performed so that the infant can be resuscitated. Ongoing large, randomized clinical trials are
examining resuscitation with the cord intact.
Clinicians who are charged with the care of
the newborn at delivery and thereafter should
be part of the decision making around the time
of cord clamping, document the time of cord
clamping as part of the resuscitation record, and
be aware of the implications of either early or
delayed clamping for subsequent care.
9,46
13,84
CHAPTER 4 Care at Birth
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71
RESUSCITATION OF THE
NEWBORN
Preparation for Resuscitation
Immediate, effective resuscitation of the newborn
infant can reduce or prevent morbidity and mortality. Much of neonatal resuscitation focuses
on accurate assessment and initiation of ventilation. Basic interventions are often all that is
necessary to successfully resuscitate a depressed
35,56,62
infant.
requires anticipation, adequate preparation of
equipment and personnel, and teamwork.
In the mid-1980s, the American Heart Association
and the American Academy of Pediatrics addressed
the need for a national training program for neonatal
resuscitation in the United States by developing the
Neonatal Resuscitation Program (NRP). The
NRP provides the training necessary for health
care professionals to put into practice the scientific consensus established and updated periodically by the International Liaison Committee on
Resuscitation (ILCOR). The ILCOR Consensus
on Science is revised according to a rigorous process
of evidence evaluation.63 Changes are then incorporated into regional guidelines and the Textbook of
Neonatal Resuscitation.
spread acceptance ensures consistent awareness
of current scientific consensus, use of proper
equipment, and preparation of personnel to
work as a team using shared knowledge and
performance skills. Helping Babies Breathe, a pro-
gram for basic resuscitation in resource-limited
settings, shares the same evidence base as the NRP;
however, it emphasizes the initial steps of resuscitation through bag-and-mask ventilation with air for
resource-limited settings where both mother and
baby may be cared for by a single birth attendant
and advanced interventions are not universally
available.
The seventh edition of the NRP recommends
the following guidelines.
At every delivery, there should be at least
one person capable of initiating resuscitation
whose only responsibility is the baby. Either
this person or another who is immediately available
should have the skills necessary to perform a complete resuscitation, including endotracheal intubation and administration of medications.
However, effective resuscitation
81,88
The program’s wide-
2,57
81
29,83
When a high-risk delivery is anticipated, two
persons whose sole responsibility is resuscitation
of the infant should be present, and their roles
should be designated in advance. Multiple births
require a full team of personnel with complete
equipment for each newborn.
Care providers responsible for the newborn
must be familiar with the prenatal and intrapartum history of the mother and fetus because
this information guides preparation for resuscitation. Preterm/postterm gestation; multiple gestation;
meconium-stained amniotic fluid; and risk factors in
the medical, obstetric, intrapartum, and social history
may identify the infant who may require skilled
resuscitation at delivery (Box 4.1).
1,8,90
However, any
normal pregnancy may become high risk at the
onset of previously unexpected or undetected
intrapartum complications, including maternal
hemorrhage, cord prolapse, and meconium staining of the amniotic fluid. Although prevention,
BOX
4.1
CONDITIONS THAT MAY REQUIRE
AVAILABILITY OF SKILLED
RESUSCITATION AT DELIVERY
Intrapartum Problems
• Fetal distress
• Persistent late decelerations
• Severe variable decelerations without baseline variability
• Bradycardia
• Meconium-stained amniotic fluid
• Cord prolapse
• Prolonged, unusual, or difficult labor
• Emergency operative or assisted delivery
• Breech presentation with vaginal delivery
• Narcotic administration to mother within 4 hours of delivery
Medical/Obstetric/Genetic Problems
• Diabetes mellitus
• Suspected or confirmed maternal infection
• Preeclampsia
• Abnormal amniotic fluid volume
• Multiple gestation
• Fetal growth deviations
• Prematurity
• Isoimmunization/hydrops
• Fetal congenital anomalies
BOX
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4.2
UNIT TWO Support of the Neonate72
EQUIPMENT USED DURING NEONATAL RESUSCITATION
Thermal Management
• Radiant warmer
• Warmed blankets or towels
• Infant stocking cap
• Food-grade plastic wrap or polyethylene bags
• Chemically activated warming pad
Airway
• Bulb syringe
• Mechanical suction
• Suction catheters—5 to 6, 8, 10, and 14 Fr
• 8-Fr feeding tube and 20-mL syringe
• Meconium aspirator/suction device
• Shoulder roll
Breathing
• Bag-and-mask ventilation
• Oxygen source with flowmeter and tubing
• Neonatal resuscitation bag with 21% to 100% oxygen capability and
manometer or pressure release valve and/or T-piece device
• Facemasks—newborn and premature sizes
• Oral airways—newborn and premature sizes
• Pulse oximeter with neonatal probe
• Oxygen blender and compressed air source
• Intubation
• Laryngoscope with extra batteries
• Straight blades—No. 0 and No. 1 with extra bulbs
• Endotracheal tubes—2.5-, 3.0-, 3.5-, and 4.0-mm internal diameter
• Stylet
• Tape, skin preparation
• Scissors
• CO2 detector
• Laryngeal mask airway
Circulation
• Stethoscope
• Wall clock or stopwatch
• Cord clamp
• Medications (epinephrine, normal saline)
• Sterile gloves
• Chlorhexidine sponges, povidone-iodine solution
• Umbilical vessel catheterization tray
• Umbilical catheters—3.5 and 5 Fr
• Three-way stopcocks
• Umbilical tape
• Suture material
• Intravenous catheters, tubing, fluid
• Needles—25, 23, 22, 20, and 18 gauge
• Syringes—1, 3, 5, 10, 20 or 30, 50, or 60 mL
• Cardiorespiratory monitor and temperature probe (for prolonged
stabilization)
• Procedure light
detection, and treatment of fetal asphyxia are the
responsibilities of the obstetric team, coordination
between obstetric and neonatal services in a “prebriefing” before delivery is vital to ensure timely and
effective resuscitation.
Resuscitation equipment, supplies, and drugs
(Box 4.2) should always be readily available, func-
tional, and assembled for immediate use in a designated location—ideally in a specific area of the
delivery/birthing room or on a radiant warmer/
intensive care bed equipped with easily accessible
storage (Figs. 4.3 and 4.4).
Prepare to facilitate normal transition or provide
neonatal resuscitation by performing the following:
• Conduct a prebriefing (Gestation? Amniotic
fluid clear? Expected number of babies? Other
risk factors?) and designate roles among the
resuscitation team.
• Prepare the mother for skin-to-skin care and
DCC.
• Preheat the radiant warmer.
• Assemble basic supplies: warm linens, head
covering for infant, suction device, cord clamp,
and appropriate personal protection.
• Check suction device and equipment for
function; set the vacuum regulator control not
to exceed 100 mm Hg.
• Turn on the air/oxygen flow to the ventilation
bag or T-piece device, and check all connections, flow-control valves, the pressure-release
valve, and manometer function to enable the
ventilation device to deliver a pressure of up to
30 to 40 cm H2O. Select the appropriate oxygen
concentration for initiation of positive-pressure
ventilation. Prepare an appropriate-size facemask
and a pulse oximeter with a neonatal probe.
FIGURE 4.3 Labor/delivery/recovery (LDR) room resuscitation area
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prepared for high-risk delivery. Blended oxygen is available from wall outlets
via T-piece device incorporated into the radiant warmer. Flow-inflating bag
and manometer are prepared with self-inflating bag as backup. Bulb suction
device and catheter for use with wall suction are available. Other supplies for
airway suctioning and intubation are stored in the drawers of the supply cart.
Resuscitation drugs and umbilical catheterization trays are kept in a separate
resuscitation cart accessible from all LDR rooms. (Photo courtesy of Children’s
Hospital Colorado, Maternal Fetal Care Unit. Photo by Tia Brayman.)
FIGURE 4.4 Patient area of radiant warmer prepared for a delivery. Supplies
needed for initial steps and ventilation include warm blankets (left rear) for drying, overhead heater for warmth, head covering, suction devices, ventilation bag
and masks, pulse oximetry probe and patient connector, stethoscope, and cord
clamp. Temperature probe and cardiorespiratory monitor connector are available
for prolonged stabilization. (Photo courtesy of Children’s Hospital Colorado,
Maternal Fetal Care Unit. Photo by Tia Brayman.)
CHAPTER 4 Care at Birth
73
• Check the laryngoscope for a bright light
source and appropriate blades (size 0 for premature infants and size 1 for term infants); tighten
the bulb.
• Check the availability of appropriate-size endo-
tracheal tubes (2.5 to 3.5 mm internal diameter).
• Locate a stethoscope of appropriate size and
confirm that it is functioning properly.
• Identify a cardiac monitor and leads for use if
positive-pressure ventilation is necessary.
• Check the ancillary equipment (e.g., umbilical
catheter supplies, intravenous solutions, unexpired resuscitation drugs, alternative airway).
• If the clinical situation warrants, draw up
and label emergency medications for ready
administration, using the estimated fetal weight,
and obtain O-negative packed red blood cells for
emergency transfusion.
The steps of transition and neonatal resuscita-
tion follow the standard ABCs of resuscitation:
A—Airway
B—Breathing
C—Circulation
With the ABCs as an overall framework for neonatal resuscitation, the components of the procedure
can be examined sequentially:
A—Establish an airway:
Position the infant.
Clear secretions from the mouth and nose as
needed.
Perform endotracheal intubation or use alter-
native airway, such as a laryngeal mask, if
necessary.
B—Initiate breathing:
Dry thoroughly.
Provide specific tactile stimulation to breathe, if
necessary.
Provide free-flow oxygen or positive-pressure
ventilation with oxygen based on gestational
age and time-specific oxygenation targets
(Table 4.2).
C—Maintain circulation:
Delay umbilical cord clamping for at least 1 min-
ute in term and preterm infants. Take steps
to establish respirations before umbilical cord
clamping.
Provide chest compressions.
Administer epinephrine and volume expander,
if indicated.
Each step of the resuscitation procedure,
whether uncomplicated or extended, is guided by
UNIT TWO Support of the Neonate74
Birth
Approximate time
*Endotracheal intubation may be considered at several steps.
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TABLE
4.2
TIME-SPECIFIC SATURATION TARGETS
AFTER BIRTH
TIME AFTER BIRTH (MINUTES) SATURATION (%)
1 60–64
2 65–69
3 70–74
4 75–79
5
80–84
10 85–95
Adapted from Weiner GM, ed. Textbook of Neonatal Resuscitation. 7th ed. Elk Grove
Village, IL: American Academy of Pediatrics and American Heart Association; 2016:77.
the evaluation/decision/action cycle. Evaluation
includes assessment of respirations, heart rate,
and oxygen saturation (Fig. 4.5).81 The impor-
tance of providing warmth, establishing an airway,
drying, and stimulating the newly born to initiate
breathing cannot be overemphasized in neonatal
resuscitation. Expansion of the lungs with air and
adequate ventilation are the keys to successful
resuscitation. Successful performance of these steps
often obviates the need for further intervention,
but inadequate lung expansion and ventilation
cannot be overcome by performing chest compressions or administering medications.
Apgar Score
The Apgar score provides a comprehensive, objective
measure of the infant’s condition in the first minutes
after birth (Fig. 4.6) . The Apgar score does not serve
as an indicator of the need for resuscitation; rather,
it quantifies an infant’s response to the extrauterine
environment and resuscitative measures. In term
and preterm infants, the Apgar score remains a valuable
predictor of infants who will need ongoing support in
the immediate perinatal period and those who are at
higher mortality risk in the neonatal period.
Although perinatal asphyxia may be associated with low Apgar scores, it is possible for
an infant to have a low Apgar score without
having asphyxia.50 For example, an infant born
to a mother who received general anesthesia may
be flaccid and have depressed reflexes and poor
respiratory efforts. Such infants usually respond
16
Pink
100
Routine care
• Provide warmth
• Clear airway
• Dry
• Assess color
Observational care
Postresuscitation care
• Term gestation?
• Clear amniotic fluid?
• Breathing or crying?
• Good muscle tone?
No
• Provide warmth
30 sec30 sec30 sec
• Position; clear airway*
(as necessary)
• Dry, stimulate, reposition
• Evaluate respirations,
heart rate, and color
Cyanotic
Apneic or
HR
HR 60
HR
• Give supple-
100
mental oxygen
Persistently cyanotic
• Provide positive pressure ventilation*
HR
60
• Provide positive-pressure ventilation*
• Administer chest compressions*
60
• Administer epinephrine*
Yes
Breathing
HR
100
& pink
Effective
ventilation
HR
& pink
FIGURE 4.5 Throughout resuscitation, the infant’s respirations, heart rate (HR),
and oxygen saturations are evaluated as a basis for decisions and actions. (From
Weiner GM, ed. Textbook of Neonatal Resuscitation. 7th ed. Elk Grove Village, IL:
American Academy of Pediatrics and American Heart Association; 2016:9.)
rapidly to bag-and-mask ventilation, and no further
intervention is necessary. However, an infant may
have an equally low Apgar score as a result of intrauterine asphyxia and may require prolonged resuscitative efforts. An infant with a midrange Apgar
score between 6 and 7 may be using homeostatic
mechanisms to maintain adequate central blood
pressure and cardiac output. Apgar scores should
be assigned at 1 and 5 minutes and every 5
minutes thereafter until the score is 7 or greater.
A complete description of the timing and nature of
resuscitative measures is vital to interpreting a low
Apgar score.
4
Although the Apgar score is not used to guide
resuscitation, the experienced clinician performs
a rapid visual assessment of an infant at the
CHAPTER 4 Care at Birth
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Sign 01 21 min 5 min 10 min 15 min 20 min
Color Acrocyanotic
Heart rate
Reflex irritability
Muscle tone
Respiration
Comments:
FIGURE 4.6 Expanded Apgar score. (From American College of Obstetricians and Gynecologists. ACOG Committee Opinion No. 333: The
Apgar score. Obstet Gynecol. 2005;106:1141.)
Blue or pale
Absent
No response
Limp
Absent
Less than
100 min
Grimace
Some flexion
Weak cry,
hypoventilation
Completely
pink
Greater than
100 min
Cry or active
withdrawal
Active motion
Good,crying
Total
Min
Oxygen
PPV/NCPAP
ETT
Chest compressions
Epinephrine
Resuscitation
1510 15 20
75
moment of birth. This rapid assessment incorpo-
rates two elements from the Apgar score, as well as a
key question that influences the overall conduct of
the resuscitation.
Rapid Assessment after Birth
In the first few seconds after birth, a rapid visual
assessment of the baby should be performed to
answer the following questions88:
• Is the baby term?
• Is the baby breathing or crying (respiratory
effort)?
• Is there good muscle tone?
If the answer to all of these questions is
“yes,” the baby can remain with the mother in
skin-to-skin contact to receive routine care as
described in the Routine Care and Initial Steps
of Resuscitation section that follows.
If the answer to any of the questions is “no,”
the infant will need further evaluation.
80
Routine Care and Initial Steps of
Resuscitation
The care of every infant at birth includes (1)
drying, (2) providing warmth, (3) clearing the
airway (positioning and suctioning if needed),
and (4) support of breathing with tactile stimulation as necessary.
Whether part of routine care or during the initial
steps of resuscitation, many of the actions can be
performed simultaneously, especially if more than
one person is caring for the infant.
DRY AND PROVIDE WARMTH
• Dry the infant thoroughly, remove wet linens,
and place him or her directly on the mother’s
abdomen; cover both with warm linens during a
delay in clamping the cord (routine care).
or
• If the infant requires positive-pressure ven-
tilation, dry thoroughly and clamp and cut
the cord, and place the infant under a radiant heat source.
or
• Wrap preterm infants less than 32 weeks of
gestation in a polyethylene sheet or bag of
food-grade plastic from the shoulders to the
toes (without drying), with the right arm
exposed for pulse oximetry probe placement;
clamp and cut the cord; and place under a radiant
heat source.
81,88
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POSITION AND CLEAR THE AIRWAY (AS
NECESSARY)
• Ensure that the infant’s neck is slightly extended
when positioning him or her on the mother’s chest;
wipe secretions from the mouth and nose or
clear the airway with a bulb suction device if
secretions are blocking the airway or the amniotic fluid contains meconium (routine care).
or
• Position the infant on a flat surface with the
neck slightly extended.
• Turn the head (or the head and body) to the side
to allow secretions to pool in the cheek, and then
remove with a cloth or suction device. Suction the
mouth and then the nose to clear the airway.
The mouth is suctioned first to clear the largest
volume of secretions; when the nasopharynx is
suctioned, a reflex cough, sneeze, or cry often
results. Deep pharyngeal suctioning in an infant not
requiring positive-pressure ventilation or intubation
should not be performed during the first few minutes after birth to avoid vagal stimulation, resultant
bradycardia, and a delay in the rise of Pao2.
STIMULATE AND REPOSITION
14,26
• Provide tactile stimulation by briefly rubbing
the back for infants who are not breathing or
crying after drying.
or
• Continue gentle rubbing of trunk, extrem-
ities, or head to support early respiratory
efforts in the newborn.
• Keep the head and neck in a slightly extended
position to maintain an open airway.
Evaluate the Infant
Evaluation of the infant is a continuous, ongoing
process. Subsequent action is guided by evaluation
during each step of resuscitation and decisions
about whether the response is adequate.
EVALUATE RESPIRATIONS
• Rate and depth of respirations (chest wall
movement, air exchange) must be adequate;
apnea and gasping respirations both require
positive-pressure ventilation.
EVALUATE HEART RATE
• The heart rate should be greater than 100
beats/min. Listen over the left side of the chest
with a stethoscope to count the heart rate. Count
the heart rate in 6 seconds and multiply by 10
for the beats per minute. Indicate each beat for
other team members by tapping the forefinger
on the bed or tapping the thumb and index finger together.
• If the heart rate is <100 beats/min or the infant
requires respiratory support, heart rate can be
measured continuously with pulse oximetry or
an electrocardiogram (ECG) monitor.
EVALUATE OXYGENATION
• Term, healthy babies may take more than 10
minutes to achieve a preductal oxygen saturation above 95% and nearly an hour to achieve the
same level in the postductal circulation.
19,39,66,73
• Give free-flow oxygen and place a pulse
oximeter probe on the right hand/wrist if the
infant is breathing but remains centrally cyanotic. Peripheral cyanosis (acrocyanosis) is not an
indication for supplemental oxygen. The goal of
oxygen administration should be normoxia
based on time-specific oxygenation targets,
not hyperoxia.
19,63
Respiratory Support With Positive
Pressure
Consider continuous positive airway pressure
(CPAP) for infants who have labored breathing and
are unable to maintain SpO2 within the target range
despite increasing oxygen concentration.
Indications for positive-pressure ventilation
in the newborn infant include the following:
• Apnea or gasping respirations despite a brief
period of tactile stimulation
• A heart rate of less than 100 beats/min
• Central cyanosis despite free-flow oxygen or
oxygen administered with CPAP
Prolonged tactile stimulation or administration of supplemental oxygen to a baby who is
not breathing effectively or who has a heart
rate of less than 100 beats/min only delays
appropriate treatment. If supplemental oxygen is
unavailable, positive-pressure ventilation should be
provided with room air. When supplemental oxy-
gen is available, it should be administered with
the goal of achieving normoxia and avoiding
hyperoxia.
has demonstrated that room air is equivalent to
100% oxygen for positive-pressure ventilation
19,63
Research in animals and humans
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77
in many newly born infants. The exclusive use
of 100% oxygen for postnatal resuscitation, as
previously recommended, can result in hyperoxia and changes induced by the generation
of oxygen free radicals.
and duration of supplemental oxygen administration should be individualized to patient needs.
Pulse oximetry, initiated as soon as feasible,
can help guide oxygen administration.18 The
ability to administer oxygen in concentrations
from 21% to 100% in the delivery setting is a
standard of care that has special importance
for preterm infants who are more vulnerable
to oxygen injury yet may need concentrations
greater than 21%.
ventilation should be initiated with 21% oxygen for infants >35 weeks. Preterm infants <35
weeks may require 21% to 30% oxygen initially to achieve target saturations. Frequently,
preterm infants who have received antenatal
corticosteroids and resuscitation with low oxygen concentrations wean back to room air by
admission to the neonatal intensive care unit
(NICU).
IMPROVE VENTILATION
• The best indication of good mask seal and
adequate lung inflation is a rising heart rate
and bilateral breath sounds. Oxygen saturation should also rise, and chest movement
should be seen with each inflation.
• If heart rate and oxygenation do not
improve, take steps to improve ventilation
by reapplying the mask and repositioning
the head, suctioning mouth and nose and
opening the mouth, increasing ventilation
pressure, and considering an alternative airway (endotracheal tube or laryngeal mask
airway).
75,77
26,47,61,78,81
The concentration
Positive-pressure
Chest Compressions
• If, after 30 seconds of effective positive-pres-
sure ventilation, the heart rate is less than
60 beats/min, intubate or insert an alternative airway, begin chest compressions (twothumb technique), and increase the oxygen
concentration to 100%. Call for help to
prepare for possible umbilical venous catheter (UVC) placement and administration of
emergency drugs.
Administration of Epinephrine and
Volume Expansion
• If the heart rate remains below 60 beats/min
despite ongoing positive-pressure ventilation
and chest compressions, ensure that ventilation and chest compressions are being given
effectively.
• If the heart rate remains below 60 beats/
min after 45 to 60 seconds of coordinated
chest compressions and effective ventilation,
administer epinephrine.
• If the baby is not responding to resuscitation,
including administration of epinephrine, and
there is evidence of blood loss or hypovolemia, consider administration of a volume
expander.
The initial steps in resuscitation should be
accomplished rapidly so that the baby is breathing spontaneously or receiving positive-pressure
ventilation by 1 minute after birth. The initial
rapid assessment can be performed in the first few
seconds after birth to determine whether routine
care can be provided to the infant in skin-toskin contact with the mother or whether more
extensive evaluation and resuscitation will be necessary during the initial steps. The initial steps of
resuscitation can be performed concurrently with
evaluation of heart rate, respirations, and oxygen
saturations, especially if more than one person is
present to care for the infant. Positive-pressure
ventilation should be performed for at least
30 seconds before moving to the next level of
intervention. When oxygen concentrations of
less than 100% are used with positive-pressure
ventilation and an adequate response in heart
rate does not occur, steps to improve lung
inflation should be taken, and then the oxygen
concentration can be increased before initiating
chest compressions. Chest compressions should
be continued for 60 seconds before pausing for
assessment. If the resuscitation proceeds to the
use of epinephrine, reassessment should occur
after 60 seconds to allow the epinephrine to
circulate.
An infant who has received more than the initial
steps of resuscitation will require close monitoring
for additional or recurrent problems during the
postnatal transition and may need supportive care
such as continued oxygen administration. Infants
who require more than brief positive-pressure
UNIT TWO Support of the Neonate78
https://t.me/medicina_free
ventilation should be monitored in a nursery
setting in which they can receive ongoing care.
4
Skills Necessary for Neonatal
Resuscitation
INITIAL STEPS: SUCTIONING FOR
MECONIUM-STAINED AMNIOTIC FLUID
Meconium-stained amniotic fluid may be seen
in infants who are more than 34 weeks of gestational age and occurs most often in term and
postterm neonates. Passage of meconium may be
associated with asphyxia. Severe fetal acidosis can
result in fetal gasping, leading to in utero aspiration
of meconium.10 Suctioning the mouth and hypopharynx at the delivery of the head and again after
complete delivery was advocated in the past to help
prevent meconium aspiration. Current evidence no
longer advises routine intrapartum suctioning for
infants with meconium-stained amniotic fluid.
Resuscitation for infants with meconium-stained
amniotic fluid should follow the same principles as
for infants born through clear fluid. The NRP no
longer recommends that any infant with meconium-stained amniotic fluid at birth receive routine
tracheal intubation for suctioning because this may
delay ventilation beyond 60 seconds after birth.
Nevertheless, any infant born with meconi-
um-stained amniotic fluid who develops signs of
airway obstruction or ineffective positive-pressure ventilation should have tracheal intubation
performed for suctioning of any meconium
present. For this reason, newborns with meconi-
um-stained amniotic fluid require notification
and availability of an appropriately credentialed
team with full resuscitation skills, including
endotracheal intubation.
ADMINISTRATION OF FREE-FLOW
OXYGEN
Supplemental oxygen should be administered
after the initial steps if the infant remains centrally cyanotic.88 The administration of oxygen
is guided by pulse oximetry to achieve time-specific saturation targets (see Table 4.2).
Oxygen delivered at a flow rate of 5 L/min may
be administered by mask or by holding the oxygen
tubing in a cupped hand over the infant’s face. The
delivered oxygen concentration decreases rapidly as
the tubing or mask is withdrawn from the face.
63,74
20,91
Once the target oxygen saturations are
achieved, gradually withdraw the oxygen tubing
or the mask from the infant’s face. If cyanosis
persists, reevaluate the quality of respirations
and the heart rate, perform a brief physical
examination, and consider bag-and-mask ventilation or intubation if there is evidence of
respiratory distress.
BAG-AND-MASK VENTILATION
The indications for bag-and-mask ventilation
include (1) apnea unresponsive to brief stimulation or gasping respirations, (2) heart rate less
than 100 beats/min, and (3) persistently low
oxygen saturation despite free-flow oxygen or
CPAP with increasing oxygen concentration.
The equipment for bag-and-mask ventilation can
be either a self-inflating bag with an oxygen reservoir and pressure-release valve or pressure gauge, a
flow-inflating bag (anesthesia bag) with a flow-control valve and pressure gauge, or a T-piece resuscitation device.
Although used widely, self-inflating bags do not
deliver consistent tidal volumes or inflation
pressures, even in the hands of providers who
resuscitate frequently. Some data suggest, how-
ever, that self-inflating bags may offer advantages
over flow-inflating bags in the hands of inexperienced operators.41 Self-inflating bags cannot
be used reliably to deliver free-flow oxygen,
and they require a special adapter to deliver
CPAP (Fig. 4.7). Ideally, they would be fitted with
a CPAP device and a manometer for use with
newborns. Flow-inflating bags require a complete
seal between mask and face to deliver a tidal
volume. They offer the capability to achieve
high peak pressures, deliver positive end-expiratory pressure (PEEP) and CPAP, and administer
free-flow oxygen. The volume of the bag should
generally be between 200 and 750 mL.81 Larger
bags are more difficult to handle and predispose to
overly large tidal volumes, especially for preterm
infants. A T-piece resuscitation device, as opposed to a
bag, can achieve desired inflation pressures and
respiratory times more consistently (at least in
mechanical models) but requires setting the
inspiratory pressure and PEEP before use and
may be more difficult to adjust during resuscitation (see Fig. 4.7).
20,28,41
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