Neonatal Resuscitation:
the NRP guidelines
Robert D. Elliott, MD, FRCPC
Department of Anaesthesia
Ottawa Hospital - General Site, University of Ottawa, Ottawa
Objectives:
After this course, the participant should be able to:
- Explain what the Neonatal Resuscitation Program is and describe its modular
organization.
- Describe the preparations of both personnel and equipment for routine and high-risk
deliveries.
- Delineate the steps involved in the initial stabilization of all neonates and the
time-frame for rapid evaluation and decision-making concerning resuscitation.
- Describe the steps and time-frame for support of ventilation and subsequent
re-evaluation leading to a decision to begin chest
- compressions.
- Describe the most current guidelines regarding ventilation and chest compressions.
- Recognize some of the problems involved in tracheal intubation of neonates and the
indications for tracheal suction in the presence of meconium.
- Describe the role of medications in the resuscitation of neonates and recommendations
concerning administration.
- Appreciate the need for "hands-on" experience by attending an NRP workshop and
becoming a certified provider.
Approximately one of every sixteen newborns will require resuscitation of some kind in
the delivery room. Every individual who is involved in providing care for both mother and
baby at the time of delivery, should ensure that he or she has the knowledge and skills
needed for neonatal resuscitation. In much the same way that adult cardiopulmonary
resuscitation was standardized in the recent past, a major effort is now under way to give
delivery-room care-providers a set of neonatal resuscitation guidelines within a
structured learning package. The result, based on the pioneering work by Ronald S. Bloom,
MD, and Catherine Cropley, RN, MN, is the Neonatal Resuscitation Program (NRP), supported
in the United States by the American Heart Association and the American Academy of
Pediatrics. In Canada, support for the NRP has come mainly from the Heart and Stroke
Foundation, at both national and provincial levels, working with a dedicated group of
nurses, paediatricians, respiratory technologists and anaesthetists.
The purpose of this CME article is to introduce the reader to the Neonatal
Resuscitation Program and to stimulate interest in developing neonatal resuscitation
skills, perhaps by attending an NRP Workshop and becoming a certified NRP Provider.
Overview
The NRP has been carefully designed in a modular fashion, with each module emphasizing
a particular skill vital for a successful resuscitation. The modules represent the
progressive steps that would occur during a full resuscitative effort of a severely
depressed neonate. The modules are as follows:
- Preparation for delivery
- Initial stabilization
- Ventilation - bag and mask
- Chest compressions
- Endotracheal intubation
- Medications
The modular form of the NRP allows tailoring the instruction to the qualifications of
the care-provider taking the course. A nurse might be trained up to and including chest
compressions and how to assist with endotracheal intubation, while physicians would be
trained to provide all resuscitative steps. For either nurse or physician, the
instructional material is the same for each module, thus ensuring a common ground for good
communication and teamwork during an actual resuscitation.
Asphyxia - The Basics
Apnea
- The asphyxiated infant passes through a series of events:
- rapid breathing and fall in heart rate
- primary apnea
- irregular gasping, further fall in heart rate and drop in blood pressure
- secondary apnea
- Most infants in primary apnea will resume breathing when stimulated. Once in secondary
apnea, infants are unresponsive to stimulation.
- Apnea at birth should be treated as secondary apnea of unknown duration (i.e. began in
utero) and resuscitation should begin at once.
Clearing Fetal Lung Fluid
- The first few breaths of a normal infant are usually adequate to expand the lungs and
clear the alveolar lung fluid.
- The pressure required to open the alveoli for the first time may be two to three times
that for normal breaths.
- Expect problems in lung fluid clearance with:
- apnea at birth
- weak initial respiratory effort caused by:
- prematurity
- depression by asphyxia, maternal drugs, or anaesthesia
Pulmonary Circulation
- At birth, pulmonary blood flow increases rapidly as the lung arterioles open up and
blood is no longer diverted through the ductus arteriosus.
- With asphyxia, hypoxemia and acidosis perpetuate pulmonary vasoconstriction and maintain
the fetal pattern of circulation.
Systemic Circulation and Cardiac Function
- Early in asphyxia, vasoconstriction in the gut, kidneys, muscles and skin redistributes
blood flow to the heart and brain as an attempt to preserve function.
- With progressive hypoxemia and acidosis, myocardial function deteriorates and cardiac
output declines.
Preparation for Delivery
Anticipate Need for Resuscitation
- Antepartum and intrapartum history may help to alert delivery-room staff about the
possibility of a depressed or asphyxiated newborn.
| Antepartum Factors |
Intrapartum Factors |
Age > 35 years
Maternal diabetes
Pregnancy-induced hypertension
Chronic hypertension
Other maternal illness
(e.g. CVS, thyroid, neuro)
Previous Rh sensitization
Drug therapy
(e.g. magnesium, lithium
adrenergic-blockers)
Maternal substance abuse
No prenatal care
Previous stillbirth
Bleeding - 2nd/3rd trimester
Hydramnios
Oligohydramnios
Multiple gestation
Post-term gestation
Small-for-dates fetus
Fetal malformations |
Abnormal presentation
Operative delivery
Premature labour
Premature rupture of membranes
Precipitous labour
Prolonged labour
Indices of fetal distress
(FHR abnormalities, biophysical profile)
Maternal narcotics
(within 4 hrs of delivery)
General anaesthesia
Meconium-stained fluid
Prolapsed cord
Placental abruption
Placenta previa
Uterine tetany |
Reproduced with permission.
© Textbook of Neonatal Resuscitation, 1987, 1990
© American Heart Association
Personnel
- At every delivery, at least one individual should be capable of performing a complete
resuscitation (i.e. including endotracheal intubation and the use of medications). In many
cases, this is the person delivering the infant.
- A second person who will be primarily responsible for the infant, must be present in the
delivery room as well, even for cases when a normal infant is expected. This person must
be able to initiate a resuscitation and if a complete resuscitation becomes necessary,
assist the fully-trained person.
- When neonatal asphyxia is anticipated, two individuals whose sole responsibility is to
the infant, should be present in the delivery room and be prepared to work as a team to
perform a complete resuscitation. The person delivering the mother must not be considered
as one of the two resuscitators.
- With multiple births, a team is needed for each infant.
- There should be no delay in initiating resuscitation; waiting a few minutes for someone
"on-call" to arrive is an unacceptable practice and invites disaster.
Equipment
- Equipment and medications should be checked as a daily routine and then prior to
anticipated need. Used items should be replenished as soon as possible after a
resuscitation.
- The delivery room should be kept relatively warm and the radiant heater should be
preheated when possible. Prewarming of towels and blankets can also be helpful in
preventing excessive heat loss from the neonate.
| Resuscitation Equipment in the Delivery Room |
Radiant Heater
Stethoscope
ECG monitor
Wall oxygen with flowmeter and tubing
Neonatal resuscitation bag
(with manometer)
Face masks, Oral airways:
- newborn and premature
Medications:
- Epinephrine (1:10,000)
- Naloxone (0.4 or 1 mg · ml-1)
- Volume expander
- Sodium bicarb (0.5mEq · ml-1) |
Suction with manometer
Bulb syringe
Suction catheters:
- 5F or 6F, 8F and 10F
Endotracheal tubes:
- 2.5, 3.0, 3.5, and 4.0 mm
ET tube stylet
Laryngoscope with straight blades:
- No. 0 & 1
Umbilical vessel catheterization tray
Umbilical catheters:
- 3.5 & 5F
Needles, syringes
Feeding tube 8F + syringe |
Initial Stabilization
Prevent Heat Loss
- Place the infant under an overhead radiant heater to minimize radiant and convective
heat loss.
- Dry the body and head to remove amniotic fluid and prevent evaporative heat loss. This
will also provide gentle stimulation to initiate or help maintain breathing.
Open the Airway
- Position the infant supine or on his or her side with the neck either in a neutral
position or slightly extended. Avoid overextension or flexion which may produce airway
obstruction. A slight Trendelenburg position may also be helpful.
- A folded towel (approximately 2.5 cm thick) placed under the infant's shoulders may be
useful if the infant has a large occiput.
- If the infant has absent, slow or difficult respirations, apply suction first to the
mouth and then nose. If the nose were cleared first the infant may gasp and aspirate
secretions in the pharynx. If mechanical suction with an 8F or 10F catheter is used, make
sure the vacuum does not exceed -13.3 kPa (-100 mmHg). Limit suctioning to 5 seconds at a
time and monitor heart rate for bradycardia which may be associated with deep
oropharyngeal stimulation.
- If meconium is present in the amniotic fluid, special suctioning may be required in the
depressed infant. (See Endotracheal Intubation below.)
Tactile Stimulation
- If drying and suctioning do not induce effective breathing, additional safe methods
include:
- slapping or flicking the soles of the feet
- rubbing the back gently
- Do not waste time continuing tactile stimulation if there is no response after 10 - 15
seconds.
Evaluate the Infant
- Respirations: Infants who are apneic or gasping despite brief stimulation
attempts should receive positive-pressure ventilation. If there is adequate spontaneous
breathing, go to next step.
- Heart Rate: Monitor either by auscultating the apical beat or by palpating the
base of the umbilical cord. If the heart rate is below 100 bpm, begin positive-pressure
ventilation, even if the infant is making some respiratory efforts. If the heart rate is
above 100 bpm, go to the next step.
- Colour: The presence of central cyanosis indicates that although there is
enough oxygen passing through the lungs to maintain the heart rate, the infant is still
not well oxygenated. Free-flow 100% oxygen at 5 l·min-1 using a mask held closely to the
infant's face should be administered until the infant becomes pink, when the oxygen should
be gradually withdrawn.
Ventilation - Bag and Mask
Equipment and Technique
- Anaesthesia Bag: This piece of ventilating equipment requires a gas flow source
to inflate. Maintaining the appropriate degree of inflation during bag and mask
ventilation requires practice. With the oxygen flowmeter set to 5-8 l · min-1 and the
oxygen tubing attached to the gas inlet nipple, inflation depends on a tight seal between
face and mask and control of the gas outflow at the end of the reservoir bag. Control is
probably best accomplished by the resuscitator's own thumb and index finger squeezing the
open end of the reservoir bag and regulating the resulting pressure in the bag by
observing an attached pressure gauge. If the reservoir bag has a flow-control valve at the
distal end, inflation control is a balance between the amount the valve is closed and the
flow-rate of the in-coming oxygen.
The advantages of the anaesthesia bag are:
- it delivers 100% oxygen to the infant
- higher peak inspiratory pressures are possible if required (pressure gauge mandatory)
- free-flow 100% oxygen can be administered through the circuit (without bag inflation)
- Self-inflating Bags: Inflation is dependent on the inherent elasticity of the
reservoir bag and not on the rate of gas flow. These bags have a second gas inlet in
addition to the one for oxygen. This inlet enables air to be entrained as the bag
reinflates to allow rapid expansion but thereby reduces the inspired oxygen concentration
to approximately 40%. By adding an extra reservoir on this secondary inlet one can
increase the delivered oxygen concentration to the 90-100% range.
Other points of note regarding the self-inflating bag include:
- most are equipped with a pressure-limiting pop-off valve that is pre-set to 30-35 cm H2O
(may not be able to generate enough pressure in some circumstances)
- delivery of O2 occurs only when the bag is compressed (not suitable for free-flow O2! )
- Face Masks: Every delivery room should have a variety of sizes: preterm, term
and large newborn. (i.e. sizes 0, 1 and 2) Anatomically shaped face masks with cushioned
rims are recommended because of better fit and tighter seal. A properly fitting mask
should cover the chin, mouth and nose and not put pressure on the infant's eyes.
Ventilating Procedure
- When ventilatory support is required, most neonates can be adequately ventilated with a
bag and mask. Positive-pressure ventilation (PPV) is indicated when:
- apnea or gasping respiration is present
- the heart rate is less than 100 beats / minute
- central cyanosis persists despite 100 O2
- Ventilation should be adequate with 40 to 60 assisted breaths per minute. Initial lung
inflation may require a pressure as high as 30-40 cm H2O but subsequent breaths should be
in the 15-20 cm H2O range.
- Adequate ventilation is assessed by observing chest wall motion and hearing breath
sounds bilaterally. If chest expansion is inadequate, the following steps should be
followed in sequence:
- reapply the face mask to rule out a poor seal
- reposition the head - extend the head a bit further - reposition the shoulder towel
- check for secretions - suction if necessary
- try ventilating with the infant's mouth slightly open - perhaps with an oral airway
- increase pressure to 20-40 cm H2O
- abandon bag and mask - intubate trachea
- After 15-30 seconds of effective ventilation, the heart rate of the neonate should be
evaluated. To save valuable time, the heart rate over a 6 second period is counted and
multiplied by 10 to give an approximation of the 1-minute heart rate. (e.g. 8 beats in 6
seconds = 80 bpm)
The next step in the resuscitation depends on the heart rate which is determined:
| HR > 100 |
| If spontaneous breath efforts are present, gradually reduce PPV and provide gentle
tactile stimulation plus free-flow O2. |
| HR < 60 |
| Immediately begin chest com- pressions and ensure that ventilation is adequate and
that 100% O2 is being delivered. |
| 60 < HR < 80 (not rising) |
| Continue ventilation and begin chest compressions. |
| 60 < HR < 100 (rising) |
| Continue ventilation |
Chest Compressions
Rationale
- Asphyxia in the neonate not only slows the heart rate but also decreases myocardial
contractility, resulting in diminished flow of blood and oxygen to vital organs. Chest
compressions can temporarily increase circulation and oxygen delivery.
- Chest compressions must always be accompanied by ventilation with 100% oxygen.
- Pressing on the sternum compresses the heart and increases the intrathoracic pressure,
causing blood to be pumped into the arterial circulation. Release of the sternal pressure
will increase venous blood to return to the heart.
Indications
- When to Begin Chest Compressions:
After 15-30 seconds of PPV with 100% O2 -
- the heart rate is below 60 bpm
- the heart rate is between 60 and 80 and not rising
- When to Stop Chest Compressions:
- the heart rate is 80 bpm or greater
Technique
- Location: Pressure should be applied to the middle third of sternum, just below
an imaginary line drawn between the nipples. Take care not to apply pressure to the
xiphoid.
- Thumb Method: Encircle the torso with both hands and compress the sternum with
both thumbs side-by-side while the fingers support the back. In very small neonates the
thumbs may have to be superimposed. Use just the tips of the thumbs to compress to avoid
squeezing the whole chest wall and fracturing ribs.
- Two-finger Method: This method is used if the resuscitator's hands are too
small to encircle the chest properly or if access to the umbilicus is necessary for
medications. The middle and ring fingers of one hand are held perpendicular to the chest
and the tips apply pressure to the sternum while the other hand is used to support the
back from below.
- Pressure: Use just enough pressure to depress the sternum 1.5 cm, then release
the pressure to allow the heart to fill. One compression consists of the downward stroke
plus the release.
- Rate: To match the heart rate of the normal neonate, the compress/release
action should be repeated 120 times per minute (2 per second).
- Cautions: Do not remove the tips of your fingers from the chest. You may waste
time relocating the compression site or end up compressing the wrong area, producing
broken ribs with the possibility of pneumothorax or a lacerated liver.
To make sure the
circulation produced by the chest compressions is adequate, the rate and the depth of the
compressions must be consistent.
Reproduced with permission.
© Textbook of Neonatal Resuscitation, 1987, 1990
© American Heart Association
Ventilation during Chest Compressions
- Positive-pressure ventilation must always accompany chest compressions. The most recent
guidelines recommend interposing chest compressions with ventilation, suggesting that
simultaneous PPV and chest compressions may affect the efficiency of ventilation,
particularly when using a bag and mask, by forcing air into the stomach. (This is probably
less of a factor if the infant's trachea is intubated.)
- A 3:1 ratio of chest compressions to ventilation is recommended. The three compressions
are followed by a pause to interpose an effective breath. The combined rate of
compressions with ventilation should be 120 per minute - resulting in 90 compressions and
30 ventilations each minute.
- Although bag and mask ventilation can be performed effectively over a prolonged period
of time, ventilation is much easier if the infant is intubated. However, it is vital that
one remembers that the priority is ventilation and not intubation, particularly if the
intubation proves difficult. Should prolonged PPV by bag and mask be necessary, an
orogastric tube should be passed to prevent distension of the stomach.
- In the intubated neonate, particularly if ventilated mechanically, one may wish to
perform the chest compressions (120 per minute) and ventilation (40-60 per minute)
independently of each other, as described by the previous version of the guidelines.
Evaluating the Heart Rate
- After the first 30 seconds of chest compressions, the heart rate should be checked.
- During the heart rate check, the chest compressions are interrupted for no more than the
6 seconds it takes to count the heart beats and make the calculation.
- If the infant is showing a positive response to the resuscitative efforts then one
should check the heart rate every 30 seconds in order to stop chest compressions when the
infant's own heart rate rises to 80 or above. Ventilation should be continued until the
heart rate is above 100 bpm.
- Should the infant's heart rate remain below 80 bpm despite at least 30 seconds of
adequate chest compressions and ventilation, resuscitation should progress rapidly to the
next step of giving medications.
Endotracheal Intubation
Indications
- In most cases, when positive-pressure ventilation is required, it should be initiated
with the bag and mask. Although some
- resuscitators will be very skilled at intubation, others with less experience may waste
valuable time, delaying resuscitation.
- Endotracheal intubation is indicated in the following circumstances:
- prolonged PPV required (to avoid gastric distension)
- bag and mask ineffective (poor chest expansion, continuing low HR)
- tracheal suctioning required (thick or particulate meconium)
- diaphragmatic hernia suspected (prevent bowel distension in the chest)
Endotracheal (ET) Tubes
- Tube Style: Sterile, disposable tubes with a uniform internal diameter (not
tapered) should be used.
- Vocal Cord Guide: Most ET tubes for neonates have a heavy black line set back
from the tip which is meant to be aligned with the vocal cords during tube insertion. This
should position the tip of the tube above the bifurcation of the trachea.
- Centimeter Markings: These markings identify the distance from the tip of the
ET tube. After intubation, the marking level with the upper lip should be noted for later
reference when checking for any change in tube position. A rule-of-thumb for the
"tip-to-lip" distance is: 6 cm + weight in Kg
- Size Selection: Tube size will depend on the infant's weight and/or gestational
age.
Tube Size
(ID mm) |
Weight
(gm) |
Gestational Age
(weeks) |
| 2.5 |
< 1000 |
< 28 |
| 3.0 |
1000-2000 |
28-34 |
| 3.5 |
2000-3000 |
34-38 |
| 3.5-4.0 |
> 3000 |
> 38 |
- Tube Preparation: The ET tube should be shortened to 13 cm to make handling
during the intubation easier and to lessen the chance of placing the tube too far into the
trachea. The use of a stylet to provide rigidity is optional but if used, care must be
taken that the stylet tip does not protrude beyond the end of the ET tube or that the
stylet cannot advance during intubation. Experienced intubators keep the ET tubes well
away from the radiant heater to retain some rigidity.
Other Equipment
- Laryngoscope: Attach to the handle the appropriate size straight (Miller)
blade: No. 0 for preterm infants and No. 1 for fullterm infants. Check that the bulb is
screwed in tightly and then click the blade into position and ensure that the light is
bright and does not flicker.
- Suction Equipment: Mechanical suction should be available and adjusted so that
when the tubing is occluded the negative pressure does not exceed 13.3 kPa (100 mmHg). A
suction catheter sized 10 F or larger should be present. Smaller catheters for suction
through ET tubes should be available.
- Resuscitation Bag and Mask connected to 100% O2: The bag and mask should be
handy to ventilate between intubation attempts or should intubation be unsuccessful. The
bag itself will be used to ventilate through the ET tube.
Technique
The NRP Textbook of Neonatal Resuscitation describes in detail and with many
excellent diagrams how to intubate a neonate. In addition, each NRP workshop allows lots
of opportunity to practice on mannikins under the direction of experienced instructors. In
this CME discussion, only some of the important tips will be highlighted.
- Positioning the Infant: The best position for intubation is on a flat surface
with the head in the midline and the neck slightly extended, perhaps with a rolled towel
under the shoulders. Hyperextending the neck will raise the trachea out of the
line-of-sight during laryngoscopy.
- Inserting the Laryngoscope Blade: Slide the blade beyond the base of the tongue
into the vallecula and lift the tongue with the entire blade by pulling the laryngoscope
handle upwards and away from you. (In very small infants it may be necessary to gently
lift the epiglottis as well.) Do not rotate the handle towards you. The glottis should
then come into view. Sometimes gentle pressure on the neck over the larynx will help bring
the glottis into line of sight.
- Placing the ET Tube: Introduce the ET tube down the right side of the mouth to
prevent it from obstructing your view of the glottis. You must be able to see the tip of
the ET tube as it passes through the vocal cords.
- Timing: Intubation attempts should be limited to 20 seconds to minimize
hypoxia. Between attempts, ventilate with a bag and mask.
Confirmation of ET Tube Placement
- If the ET tube is correctly placed in the mid-tracheal region, the following signs
should be present:
- air enters both sides of the chest (Listen in the axillae to avoid mistaking
air entering the stomach for breath sounds.)
- breath sounds are equal in intensity
- symmetrical rise of the chest with each breath
- no air heard entering the stomach
- no abdominal distension
- improvement in colour, heart rate and activity of the neonate
- A chest X-ray should be obtained for final confirmation if the tube is to stay in place
beyond the initial resuscitation.
| Complications of Intubation |
| Hypoxia |
Taking too long to intubate
Incorrect placement of tube |
| Bradycardia/Apnea |
Hypoxia
Vagal response due to stimulation of posterior pharynx (laryngoscopy, suction) |
| Pneumothorax |
Excessive pressure during ventilation or ET tube in right mainstem bronchus |
Contusions or Lacerations
(tongue, gums,epiglottis, cords) |
Rough handling of laryngoscope or ET tube
Laryngoscope blade too long or too short |
| Perforation of trachea or esophagus |
Insertion of tube too vigorous or stylet protrudes beyond end of ET tube |
| Infection |
Organisms introduced via equipment or hands |
Reproduced with permission.
© Textbook of Neonatal Resuscitation, 1987, 1990
© American Heart Association
Tracheal Suction for Meconium Aspiration
- About one in eight deliveries are complicated by the presence of meconium in the
amniotic fluid. Thorough suctioning of the nose, mouth and posterior pharynx before
delivery of the shoulders does appear to decrease the risk of meconium aspiration and
should be performed whether the meconium is thin or thick. A large-bore (12F or 14F)
suction catheter should be used with mechanical suction.
- If meconium is present in an infant with respiratory difficulties, then immediately
after delivery the posterior pharynx should be cleared under direct vision using a
laryngoscope and suction catheter. If the meconium is thin and the newborn is vigorous,
then tracheal suctioning is probably not required.
- If the neonate is depressed or the meconium is thick or particulate, then direct
endotracheal suctioning should be performed. (See note #6)
- If indicated, tracheal suctioning should be performed as soon as possible after
delivery. Once the ET tube is placed in the trachea, suction is applied directly to the
tube to evacuate the thick, tenacious material. The suction is controlled by placing an
adapter called a meconium aspirator between the ET tube connector and the suction tubing.
Continuous suction not exceeding -13.3 kPa (-100 mmHg) is applied as the tube is slowly
withdrawn.
Reproduced with permission.
© Textbook of Neonatal Resuscitation, 1987, 1990
© American Heart Association
- Reintubation and suctioning should be repeated as long as significant amounts of
meconium are removed, although twice is usually adequate. It may not be possible to remove
all meconium from the trachea before the status of the infant requires positive-pressure
ventilation with oxygen. When one should stop will be a judgement call usually based on
what is happening with the neonate's heart rate.
- Canadian experience concerning meconium aspiration has been recently examined and
somewhat different guidelines are being developed for Canada. A major premise is that
attempts to suction meconium from the trachea appear to have a limited impact on the
incidence of meconium aspiration syndrome, probably because hypoxia in utero plays a
central role in the pathogenesis. The risk of morbidity associated with endotracheal
intubation may be actually greater than the chance of modifying the incidence or severity
of the illness. The new Canadian guidelines will recommend that an infant born with
meconium (either thin or thick), who is breathing and crying vigorously, should not be
subjected to direct visualization of the larynx or attempts to suction the trachea.
Medications
Routes of Administration
Endotracheal Instillation: Some drugs may be injected via the endotracheal
tube to take advantage of rapid absorption through the bronchial mucosa. To ensure that
enough drug gets beyond the end of the ET tube, one may wish to dilute the calculated
volume of drug up to 1 to 2 ml with normal saline. Alternately, a 5F feeding catheter
inserted down the ET tube can be used to inject these small volumes of drug, and then
flushed with 0.5 ml of saline. To help distribute the drug deep into the bronchial tree,
positive-pressure ventilation should be given immediately after the drug is injected down
the ET tube. Umbilical Vein: The umbilical vein, being fairly easy to isolate and
cannulate, is the most common route for giving drugs during a major resuscitation event.
An umbilical catheter is radiopaque, has a single end hole and is either 3.5 or 5.0 F in
size. The catheter is inserted under sterile setup into the vein of the umbilical stump,
advancing the tip until it lies just below the skin level with free flow of blood still
present. The major concern is too deep an insertion with the risk of infusion of
hypertonic and vasoactive medications directly into the liver.
Drugs and Fluids
For the majority of infants who require resuscitation, the only "medication"
needed will be 100% oxygen delivered with effective ventilation. Some will require chest
compressions. In only a very few infants will this next step be necessary.
- Epinephrine:
- Indications:
- - the heart rate stays below 80 despite effective ventilation with 100% oxygen and chest
compressions for at least 30 seconds
- - the heart rate is zero
- Rationale:
- Epinephrine has both a- and b-adrenergic stimulating properties. The alpha effect causes
vasoconstriction which raises the perfusion pressure during chest compressions, augmenting
oxygen delivery to both heart and brain. The beta effect enhances cardiac contractility,
stimulates spontaneous contractions and increases heart rate.
- Comments:
- This drug can be given either intravenously or via an ET tube and can be repeated every
3 to 5 minutes if required. The ET tube route may result in lower plasma concentrations;
therefore, neonates who fail to respond to epinephrine via the ET tube, should have
intravenous access established. If intravenous access is unavailable and the infant has
failed to respond to standard dosage, one should consider raising the endotracheal dose of
epinephrine by a factor of ten (to 0.1-0.2 mg · kg-1).
- Volume Expanders:
- Indications:
- Signs of hypovolemia. A 20% or greater loss in blood volume should be suspected when
there is:
- pallor persisting after oxygenation
- a weak pulse despite a good heart rate
- decreased blood pressure ( under 55/30 )
- poor response to resuscitative efforts
- Rationale:
- Hypovolemia occurs more frequently in the newborn than is commonly recognized. Blood
loss is often not obvious and initial tests of hemoglobin and hematocrit are usually
misleading. The increase in vascular volume secondary to a volume expander should improve
tissue perfusion and reduce the development of metabolic acidosis.
- Comments:
- The most commonly used volume expanders are:
- normal saline or Ringer's lactate
- 5% albumin-saline or other plasma substitute
- O-negative blood cross-matched with the mother's blood
- The volume for infusion should be 10 ml · kg-1 and should be given over 5 to 10
minutes.
- Naloxone:
- Indications:
- Naloxone is indicated in the infant for reversal of respiratory depression secondary to
maternal opioids given within 4 hours prior to delivery.
- Rationale:
- Naloxone is a pure opioid antagonist without intrinsic respiratory depression activity.
It works very rapidly but attempts to give this drug should always be preceded by adequate
ventilatory assistance. The duration of action of naloxone may be shorter than that of
some opioids making continued respiratory monitoring mandatory for a further 4 to 6 hours.
- Comments:
- Naloxone can be given either endotracheally or intravenously. If perfusion is adequate,
then the subcutaneous or intramuscular routes may be appropriate but expect a delayed
onset of action. If maternal opioid addiction is suspected, it is probably prudent not to
give naloxone (to avoid a withdrawal reaction: severe neonatal seizures) but to support
ventilation until respiratory drive is adequate.
- Other Medications:
In most cases the CPR involved with
neonatal resuscitation will be brief. There is little evidence that during the acute phase
of resuscitation in the delivery room that there will much need for drugs such as
atropine, calcium and sodium bicarbonate.
During a prolonged arrest, with confirmation of metabolic acidosis by arterial blood gas
determination, sodium bicarbonate may be beneficial. Effective ventilation must precede
and accompany the administration of sodium bicarbonate. The risk of intraventricular
hemorrhage may be decreased if the 4.2% (0.5 mEq · ml-1) solution is used and the drug is
given slowly - at least over 2 minutes. The appropriate dose is 2 mEq · kg-1 IV.
An infant who has been resuscitated with epinephrine, a volume expander and possibly
sodium bicarbonate and still has evidence of low cardiac output and poor peripheral
perfusion may benefit from a infusion of dopamine, beginning at 5 mcg · kg-1 · min-1 and
increasing to 20 mcg · kg-1 · min-1 as necessary.
Medications for Neonatal Resuscitation
| Drug |
Syringe |
Dosage |
Rate/Precautions |
Epinephrine
(1:10,000) |
1 ml |
0.01-0.03mg · kg-1
(0.1-0.3 ml · kg-1) |
Give rapidly IV or ET
Repeat q3-5 min
(ET: dilute to 1-2 ml with NS) |
Volume Expanders
NS or RL
5% Albumin
O-neg Blood |
40 ml |
10 ml · kg-1 |
Give IV over 5-10 min |
Naloxone
(0.4 mg·ml-1)
(1.0 mg·ml-1) |
1ml
1ml |
0.1 mg · kg-1
(0.25 ml·kg-1)
(0.1 ml·kg-1) |
Give rapidly
IV or ET preferred |
| Reserved for prolonged resuscitations only |
Sodium Bicarbonate
(0.5 mEq·ml-1 = 4.2% soln) |
10 ml
(x2) |
2 mEq · kg-1
(4 ml · kg-1) |
Give slowly, over at least 2 min, IV ONLY, Infant must be ventilated |
Dopamine
(6 x weight in kg = mg of dopamine diluted to 100 ml) |
100 ml |
5-20 mcg·kg-1·min-1
(5-20 ml · hr-1) |
Continuous infusion by pump |
Postresuscitation Care
- Newborns who have been successfully resuscitated will require close monitoring in a
neonatal intensive care unit or an area where special care by trained observers is
possible.
- Postresuscitation care may include:
- arterial pH and blood gas determinations
- correction of documented metabolic acidosis
- use of volume expanders and/or pressors if hypotension persists
- appropriate fluid therapy
- treatment of seizures
- screening for hypoglycemia and hypocalcemia
- chest X-rays for diagnostic purposes and ET tube position checks
- Complete documentation of all observations and actions should be entered in the infant's
chart. This should include recording the APGAR scores calculated at one and five minutes.
If the 5-minute APGAR score is less than 7, then additional scores should be obtained
every 5 minutes for up to 20 minutes or until two successive scores are 8 or greater.
Although the APGAR score is not used as a decision-making tool, it has been of value in
assessing the progress of the resuscitation.
Conclusion
This article is simply an overview of the Neonatal Resuscitation Program syllabus. An
important part of an actual NRP course involves learning the necessary skills and then
integrating them with the protocols in case scenarios. Only by working through a simulated
resuscitation can one be sure that he or she can translate written guidelines into
effective action.
References
- Bloom RS, Cropley C. Textbook of Neonatal Resuscitation. ed. Chameides L and the AHA/AAP
Neonatal Resuscitation Steering Committee. American Heart Association, 1990.
- Emergency Cardiac Care Committee and Subcommittees, American Heart Association.
Guidelines for cardiopulmonary resuscitation and emergency cardiac care, VII: neonatal
resuscitation. JAMA 1992; 268:2276-2281.
- Christenson JM, Solimano AJ, Williams J, et al. The new American Heart Association
guidelines for cardiopulmonary resuscitation and emergency cardiac care: presented by the
Emergency Cardiac Care Subcommittee of the Heart and Stroke Foundation of Canada. Can Med
Assoc J 1993; 149: 585-590.
- Canadian National Guidelines for Neonatal Resuscitation (draft - to be published Summer
1994). Personal communication with the Canadian Neonatal Resuscitation Program Committee.
a) Regarding personnel for resuscitation:
- For a low risk neonate, the prime resuscitator needs to be capable of taking the
resuscitation only up to and including tracheal intubation
- For every delivery there must be one person present who is primarily responsible for the
infant and who can initiate resuscitation immediately.
- For a high-risk delivery, the obstetrical circulating nurse should be ready to assist
the one person assigned to care for the neonate, if required.
- As long as a person capable of initiating resuscitation is "in-house" on a
pager, attendance at delivery is not mandatory.
- With a twin birth, two resuscitators should be sufficient for two neonates.
b) During the initial stabilization phase of resuscitation:
- Oropharyngeal suction should be vigorous and meticulous in all infants.
- The three physical signs used to evaluate the infant are: respirations, heart rate and
muscle tone.
- Suctioning should begin with the nose and then the mouth.
- Besides drying and suctioning, other acceptable methods of stimulation include flicking
the soles of the feet and rubbing the back gently.
- As long as the heart rate is > 100 bpm in a neonate who occasionally gasps, continue
tactile stimulation for up to 45 secs before starting positive- pressure ventilation.
c) Regarding ventilation with bag and mask:
- Both the anaesthesia and self-inflating bags can deliver oxygen without squeezing the
bag.
- Positive-pressure ventilation is indicated only when the heart rate stays below 80 bpm.
- Ventilation should be 20 to 40 breaths per minute (without chest compressions).
- The pressure necessary for breaths should be in the 15-20 cm H2O range (although the
first few breaths may require higher pressures).
- Adding a reservoir on to the secondary inlet of a self-inflating bag will increase the
delivered oxygen concentration from 40% to approximately 70%.
d) With respect to chest compressions:
- One should start chest compressions before ventilation if no heart beat is present.
- The correct location for thumb placement is 2.5 cm below an imaginary line drawn between
the nipples.
- One should start chest compressions after 15-30 secs of PPV with 100% oxygen, if the
heart rate is still 90 bpm.
- Use just enough pressure to depress the sternum 2.5 cm.
- The new guidelines recommend a pause after every three chest compressions to interpose
one effective ventilation, resulting in 90 compressions and 30 ventilations per minute.
e) Concerning the presence of meconium at a delivery:
- Intubation and tracheal suction should be repeated until no further meconium is returned
despite a heart rate less than 60 bpm, because the mortality associated with meconium
aspiration is so high.
- In a vigorously breathing and crying neonate, tracheal suctioning is required only when
the meconium is thick and particulate (new Canadian guidelines).
- If the neonate is depressed or having respiratory difficulties, then tracheal suction is
indicated even if the meconium is thin.
- Suctioning on the perineum, before delivery of the shoulders, of the nose, mouth and
pharynx does not seem to reduce the risk of aspiration.
- Suction as high as -150 mmHg may have to be used to remove meconium.
f) Regarding the use of medications during the resuscitation of a 3 kg neonate:
- If there is no heart rate present at birth, ventilation with 100% O2 and chest
compressions should begin immediately, followed
- by epinephrine 0.3-0.9 ml of 1:10,000 diluted to 2 ml with NS down the ET tube.
- Naloxone 0.3 mg should be given if the mother is a known narcotic addict.
- If indicated, Ringer's lactate 30 ml should be given very cautiously over 15-20 minutes.
- Sodium bicarbonate 4.2% - 12 ml - should be given early in the resuscitation for
suspected metabolic acidosis.
- If the infant fails to respond to standard doses of epinephrine down the ET tube, one
may increase the dose to a maximum of double the recommended iv dosage.
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