Extensive physiologic changes Perinatal Physiology The transition from life in utero to life outside the womb involves multiple changes in physiology and function. Also see Perinatal Problems. (See also Liver Structure and Function and Neonatal... read more accompany the birth process, sometimes unmasking conditions that posed no problem during intrauterine life. For that reason, a person with neonatal resuscitation skills must attend each birth. Gestational age Gestational Age Gestational age and growth parameters help identify the risk of neonatal pathology. Gestational age is the primary determinant of organ maturity. Gestational age is loosely defined as the number... read more and growth parameters Growth Parameters in Neonates Growth parameters and gestational age help identify the risk of neonatal pathology. Growth is influenced by genetic and nutritional factors as well as intrauterine conditions. Growth parameters... read more help identify the risk of neonatal pathology.
About 10% of neonates require some respiratory assistance at birth. Less than 1% need extensive resuscitation. There are numerous causes of depression requiring resuscitation at birth ( see Table: Problems in the Neonate That May Require Resuscitation at Birth Problems in the Neonate That May Require Resuscitation at Birth ). The need for resuscitation rises significantly if birthweight is < 1500 g.
The Apgar score is used to describe a neonate's cardiorespiratory and neurologic condition at birth. The score is not a tool to guide resuscitation or subsequent treatment and does not determine the prognosis of an individual patient.
The Apgar score assigns 0 to 2 points for each of 5 measures of neonatal health (Appearance, Pulse, Grimace, Activity, Respiration— see Table: Apgar Score Apgar Score ). Scores depend on physiologic maturity and birthweight, maternal perinatal therapy, and fetal cardiorespiratory and neurologic conditions. A score of 7 to 10 at 5 minutes is considered normal; 4 to 6, intermediate; and 0 to 3, low.
There are multiple possible causes of low (0 to 3) Apgar scores, including severe, chronic problems that have a poor prognosis and acute problems that can be quickly resolved and have a good prognosis. A low Apgar score is a clinical finding and not a diagnosis.
All blue, pale
Pink body, blue extremities
< 100 beats/minute
> 100 beats/minute
Reflex response to nasal catheter/tactile stimulation
Some flexion of extremities
* A total score of 7–10 at 5 minute is considered normal; 4–6, intermediate; and 0–3, low.
Neonatal resuscitation should follow the most recent recommendations of the American Academy of Pediatrics and the American Heart Association ( 1 General reference Extensive physiologic changes accompany the birth process, sometimes unmasking conditions that posed no problem during intrauterine life. For that reason, a person with neonatal resuscitation... read more ).
Preparation is essential. Identify perinatal risk factors, assign roles to team members, and prepare and check equipment:
At least 1 person skilled in the initial steps of neonatal resuscitation, including giving positive pressure ventilation (PPV), should be in attendance at every birth, and additional personnel with the ability to do a complete resuscitation should be rapidly available even in the absence of specific risk factors. A team of 4 or more members may be required for a complex resuscitation, and depending on the risk factors, it may be appropriate for the entire resuscitation team to be present prior to the birth.
Before a preterm delivery, set room temperature to 23 to 25° C (74 to 77° F).
A thermal mattress, hat, and plastic bag or wrap should be used for premature infants < 32 weeks gestation.
There are many perinatal risk factors that increase the likelihood of a need for resuscitation. In addition to those noted in table Problems in the Neonate That May Require Resuscitation Problems in the Neonate That May Require Resuscitation at Birth , some other risk factors include
Lack of prenatal care
Gestational age < 36 weeks or ≥ 41 weeks
Need for forceps, vacuum assist or emergency cesarean delivery
Shoulder dystocia, breech, or other abnormal presentation
Certain abnormal heart rate patterns in the fetus
Signs of infection in the infant
Maternal risk factors (eg, fever, untreated or inadequately treated group B strep infection)
Algorithm for resuscitation of neonates
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* PPV: Initiate resuscitation with room air (21% O2) for term infants or 21 to 30% O2 for preterm infants. If SpO2 targets are not achieved, titrate inhaled oxygen concentration upward.
† 3:1 compression:ventilation ratio with a total of 90 compressions and 30 breaths/minute. Compressions and ventilations are delivered sequentially, not simultaneously. Thus, give 3 compressions at a rate of 120/minute, followed by 1 ventilation over 1/2 second.
CPAP = continuous positive airway pressure; ECG = electrocardiography; ETT = endotracheal tube; HR = heart rate; PPV = positive pressure ventilation; SpO2 = oxygen saturation; UVC = umbilical venous catheter.
Adapted from the American Heart Association. 2020 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Part 5: Neonatal Resuscitation. © Copyright 2020 American Heart Association.
Initial measures for all neonates include
Rapid assessment (within 60 seconds of birth) of breathing, heart rate, and color
Providing warmth to maintain a body temperature of 36.5 to 37.5° C
Suctioning, including the use of a bulb syringe, is indicated only for infants who have obvious airway obstruction or who require positive pressure ventilation.
A 30-second delay in clamping the umbilical cord is recommended for preterm and term infants who do not need resuscitation. There is insufficient evidence to recommend delayed cord clamping in infants who do require resuscitation.
For the 90% of neonates who are vigorous and do not need resuscitation, establish skin-to-skin contact with the mother as soon as feasible.
The need for resuscitation is based primarily on the baby’s respiratory effort and heart rate. A 3-lead cardiac monitor is the preferred way to assess heart rate. In addition to clinical evaluation of respiration, monitor oxygen saturation using pulse oximetry with a preductal probe (ie, on the right wrist, hand, or finger), taking into account the expected slow rise in oxygen saturation over the first 10 minutes of life (see table Neonatal Oxygen Saturation Targets Neonatal Oxygen Saturation Targets ).
Neonatal Oxygen Saturation Targets
Time After Delivery
≥ 10 minutes
* The right upper extremity receives preductal blood.
SpO2 = oxygen saturation.
Ventilation and oxygenation
If the neonate’s respiratory effort is depressed, stimulation by flicking the soles of the feet and/or rubbing the back may be effective. Suctioning, unless indicated for airway obstruction, is not an effective method of stimulation and may cause a vagal response with apnea and bradycardia.
For infants with a heart rate of ≥ 100 beats/minute who have respiratory distress, labored breathing, and/or persistent cyanosis, supplemental oxygen Oxygen Initial stabilization maneuvers include mild tactile stimulation, head positioning, and suctioning of the mouth and nose followed as needed by Supplemental oxygen Continuous positive airway... read more and/or continuous positive airway pressure (CPAP) Continuous Positive Airway Pressure (CPAP) Initial stabilization maneuvers include mild tactile stimulation, head positioning, and suctioning of the mouth and nose followed as needed by Supplemental oxygen Continuous positive airway... read more is indicated.
For infants with a heart rate of 60 to < 100 beats/minute who have apnea, gasping, or ineffective respirations, positive pressure ventilation (PPV) using a mask is indicated. Before giving PPV, the airway should be cleared by gently suctioning the mouth and nose with a bulb syringe. The infant’s head and neck are supported in the neutral (sniffing) position, and the mouth is slightly opened with the jaw brought forward. Initial ventilator settings for a term infant are peak inspiratory pressure (PIP) of 20 to 25 cm H2O, positive end-expiratory pressure (PEEP) of 5 cm H2O, and an assist control (AC) or intermittent mandatory ventilation (IMV) rate of 40 to 60 breaths/minute. There are insufficient data to recommend a specific inspiratory time, but inflations of > 5 seconds are not recommended.
If the heart rate is < 60 beats/minute, neonates require endotracheal intubation Intubation and chest compression Extensive physiologic changes accompany the birth process, sometimes unmasking conditions that posed no problem during intrauterine life. For that reason, a person with neonatal resuscitation... read more .
The effectiveness of ventilation is judged mainly by rapid improvement in the heart rate. If the heart rate does not increase within 15 seconds, adjust the mask to ensure a good seal, check the position of the head, mouth, and chin to ensure the airway is open, suction the mouth and airway using a bulb syringe and/or a size 10 to 12 F catheter, and assess chest wall rise. Increase the airway pressure to ensure the chest wall rises adequately. Although the peak inspiratory pressure (PIP) should be set at the minimum level to which the infant responds, an initial PIP of 25 to 30 cm H2O may be required to produce adequate ventilation in a term infant. Most of the time, premature infants need lower pressures to obtain adequate ventilation. Because even brief periods of excessive tidal volume can easily damage neonatal lungs, particularly in premature infants, it is important to frequently assess and adjust PIP during resuscitation. Devices that measure and control tidal volume during resuscitation have been described and may be helpful, but their role currently is not established.
Supplemental oxygen should be provided with a blender to allow the oxygen concentration to be varied in accord with the infant’s clinical condition. Positive pressure ventilation should be initiated with 21% O2 (room air) for term infants or 21 to 30% O2 for preterm infants ≤ 35 weeks and titrated as indicated by pulse oximetry. Hyperoxia (O2 saturation > 95%) should be avoided. Infants who have otherwise responded well to resuscitation but who are persistently cyanotic may have congenital heart disease Diagnosis Congenital heart disease is the most common congenital anomaly, occurring in almost 1% of live births ( 1). Among birth defects, congenital heart disease is the leading cause of infant mortality... read more .
Intubation and chest compression
If the infant fails to respond to positive pressure ventilation delivered by mask or the heart rate is < 60 beats/minute, the infant should undergo endotracheal intubation Mechanical Ventilation Initial stabilization maneuvers include mild tactile stimulation, head positioning, and suctioning of the mouth and nose followed as needed by Supplemental oxygen Continuous positive airway... read more . Immediate endotracheal intubation is indicated if PPV is required for an infant with a prenatally diagnosed or clinically suspected diaphragmatic hernia Diaphragmatic Hernia Diaphragmatic hernia is protrusion of abdominal contents into the thorax through a defect in the diaphragm. Lung compression may cause persistent pulmonary hypertension. Diagnosis is by chest... read more . PPV with a bag and mask should be avoided in this circumstance so as not to inflate the bowel and further compromise the lungs.
The size of the tube and depth of intubation are selected according to the infant's weight and gestational age.
For endotracheal tube diameter:
2.5 mm for infants < 1000 g or < 28 weeks gestation
3 mm for infants 1000 to 2000 g or 28 to 34 weeks gestation
3.5 mm for infants > 2000 g or > 34 weeks gestation
For insertion depth, the marker at the lip should typically be at
5.5 to 6.5 cm for infants who weigh < 1 kg
7 cm for infants who weigh 1 kg
8 cm for infants who weigh 2 kg
9 cm for infants who weigh 3 kg
Many endotracheal tubes have insertion markings to be positioned at the level of the vocal cords to guide the initial placement.
Immediately after intubation, clinicians should listen for bilaterally equal breath sounds. Selective intubation of the right mainstem bronchus with decreased breath sounds on the left is common if the tube is inserted too deeply.
Tracheal intubation should be confirmed by testing for exhaled CO2 using a colorimetric detector. A positive test, in which the colorimetric indicator turns from purple/blue to yellow, confirms tracheal intubation. A negative test is most commonly due to esophageal intubation but may occur when ventilation is insufficient or there is very poor cardiac output. A fixed yellow color can be due to direct contamination by epinephrine or may indicate the device is defective.
Proper endotracheal tube depth should result in the tip of the tube being about halfway between the clavicles and the carina on chest x-ray, coinciding roughly with vertebral level T1-T2.
For infants ≥ 34 weeks (or ≥ 2000 g), a laryngeal mask airway may be used if there is difficulty intubating the infant. Infants of any gestational age can be sustained with appropriate bag-and-mask PPV if team members are unable to place an endotracheal tube. In these infants, a nasogastric tube should be placed to allow for decompression of the stomach.
After intubation, if the heart rate does not improve and there is insufficient chest rise with adequate peak inspiratory pressure, the airway may be obstructed and suctioning should be done. Thinner-diameter catheters (5 to 8 F) may clear an endotracheal tube of thin secretions but are ineffective for thick secretions, blood, or meconium. In such cases, the endotracheal tube can be removed while applying continuous suction with a meconium aspirator and sometimes the trachea can be directly suctioned with a larger (10 to 12 F) catheter. After suctioning the trachea, the infant is reintubated.
If the infant is adequately ventilated and the heart rate remains < 60 beats/minute, chest compressions should be given using the 2-thumb/chest encircling technique in a coordinated ratio of 3 compressions to 1 ventilation with 90 compressions and 30 ventilations per minute. The 2-finger technique of chest compression is no longer recommended. Intubation is always indicated before initiating chest compression, and the oxygen concentration should be increased to 100%. The heart rate should be reassessed after 60 seconds of chest compressions.
If severe bradycardia persists while the infant is adequately ventilated and chest compressions have been given for 1 minute, catheterize the umbilical vein or place an intraosseous needle to give intravascular epinephrine as soon as possible. While access is being established, a dose of epinephrine may be given via the endotracheal tube, but the efficacy of this route is unknown. The dose of epinephrine is 0.01 to 0.03 mg/kg (0.1 to 0.3 mL/kg of the 0.1 mg/mL solution, previously known as 1:10,000 solution), repeated as needed every 3 to 5 minutes. Higher doses of epinephrine have been considered in the past but are no longer recommended.
Failure to respond to resuscitation
If the infant fails to respond to resuscitation and has pallor and/or poor perfusion, volume expansion with 10 mL/kg of 0.9% saline IV over 5 to 10 minutes is recommended. Uncross-matched, O-negative packed red blood cells also may be used for volume expansion, especially if there has been acute, severe blood loss.
Drugs such as sodium bicarbonate and atropine are not recommended in the course of resuscitation. Naloxone is not recommended in the initial steps of the management of respiratory depression, and a 2018 Cochrane review found insufficient evidence to determine the safety and efficacy of this drug in neonates.
If the infant fails to respond to resuscitation or suddenly deteriorates after an initial response, pneumothorax Pneumothorax Pulmonary air-leak syndromes involve dissection of air out of the normal pulmonary airspaces. (See also Overview of Perinatal Respiratory Disorders.) Extensive physiologic changes accompany... read more must be ruled out. Although pneumothorax may be clinically suspected by finding unilateral diminished breath sounds on auscultation, breath sounds are well-transmitted across the precordium and the presence of bilateral breath sounds can be misleading. Transillumination of the chest may be used but is often limited by the lack of an immediately available intense light source and the inability to sufficiently darken the room. Additionally, a pneumothorax may be misdiagnosed in small infants with thin skin or missed in large infants with thick skin. A chest x-ray typically takes too much time to be of practical benefit during resuscitation, but bedside ultrasonography offers the possibility of an accurate and rapid diagnosis. Because pneumothorax is a reversible cause of unresponsiveness to resuscitation, bilateral thoracentesis should be considered on empirical grounds even in the absence of a definite diagnosis.
In some cases, thoracentesis is diagnostic and therapeutic for an unsuspected pleural effusion.
In some cases, resuscitation may not be appropriate:
Infants with known lethal anomalies diagnosed before birth: Consult with the family well before the delivery to arrive at a mutually agreeable plan.
Extremely premature infants Premature Infants An infant born before 37 weeks gestation is considered premature. Prematurity is defined by the gestational age at which infants are born. Previously, any infant weighing 2.5 kg was termed premature... read more : Follow institutional guidelines, bearing in mind that prenatal gestational age estimates are often not precise.
In infants with unsuspected severe anomalies discovered at delivery, an initial diagnosis and/or prognosis may be inaccurate, so resuscitation should be attempted.
When possible, a neonatologist should be involved in threshold of viability decisions. Obstetric dating data should be obtained directly from the mother as well as from the mother’s records and used to independently calculate the estimated date of confinement and possible range of gestational age Gestational Age Gestational age and growth parameters help identify the risk of neonatal pathology. Gestational age is the primary determinant of organ maturity. Gestational age is loosely defined as the number... read more . Discussion with parents should take into account current local and national outcomes data based on expected gestational age and birthweight (if known), fetal sex, singleton/multifetal gestation status, and antenatal treatment with corticosteroids. In cases in which there is a range of acceptable approaches, the parents’ input is the most important factor in determining whether to attempt resuscitation. In cases in which resuscitation clearly is not indicated, a decision for comfort care should be made by the providers, and the parents should not be offered a false choice of resuscitation.
The goal of resuscitation for most families and physicians is the survival of the infant without severe morbidity. An infant who is born without any detectable vital signs and fails to recover any sign of life in spite of appropriate resuscitation for > 10 minutes is unlikely to achieve this goal, and discontinuation of resuscitation under such circumstances is considered reasonable according to guidelines in the Textbook of Neonatal Resuscitation ( 1 General reference Extensive physiologic changes accompany the birth process, sometimes unmasking conditions that posed no problem during intrauterine life. For that reason, a person with neonatal resuscitation... read more ). However, there are no firm guidelines as to how long resuscitation should be continued when there is persistent severe bradycardia, or on what to do when the heart rate increases after resuscitation has been stopped. In such cases, the appropriateness of intervention should be evaluated in light of the goals of treatment.
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