INTRODUCTION
- Of approximately 4 million neonatal deaths globally, 23% are accounted by birth asphyxia.
- The outcome of thousands of newborns born each year can be improved by widespread use of resuscitation taught and practiced appropriately and systematically. Studies show that resuscitation training has significantly reduced neonatal and perinatal mortality and morbidity.
- About 8–10% of the newborns require some assistance at birth and less than 1% need extensive resuscitative measures including chest compressions or emergency medications (Fig. 1).
- It is difficult to predict requirement of assistance at birth; therefore, teams capable of performing neonatal resuscitation should be prepared to act promptly and efficiently in providing lifesaving interventions at every birth.
- At the time of delivery, focus should be on providing interventions such as drying, keeping the baby warm, clearing the airway, stimulation to breathe, and providing positive pressure breaths. These simple interventions can save many babies.
Fig. 1: Requirement of resuscitation.Source: Adapted from Wall SN, Lee AC, Niermeyer S, et al. Neonatal resuscitation in low-resource settings: what, who, and how to overcome challenges to scale up? Int J Gynaecol Obstet. 2009;107:S47-62, S63-4.
PATHOPHYSIOLOGY
- Ventilation of the baby's lung is the most important and effective step in neonatal resuscitation. The most common cause for need of resuscitation is inability to breathe effectively at birth leading to inadequate gas exchange. This can result in respiratory failure before, during or after birth.
- In utero, respiratory function is performed by the placenta. The placenta functions in transfer of oxygen from the mother to fetus and removal of CO2. In case placental diffusion fails, there is insufficient transfer of oxygen to fetus causing inability to support normal cellular functions and CO2 cannot be removed. Fetal monitoring may show a decrease in fetal activity, loss of heart rate (HR) variability, and HR decelerations.
- Before birth only a small quantity of blood flows to the lungs because of the increased resistance to flow [increased pulmonary vascular resistance (PVR)] in the pulmonary vessels. There is no gas exchange in the lung and lung sacs are filled with fluid. Blood returning to the right side of the heart from the umbilical vein has the highest oxygen saturation.
- After birth, baby breathes and the umbilical cord is clamped (loss of the placenta—low resistance circuit), systemic vascular resistance (SVR) increases, fluid in alveoli absorbed and replaced by air, blood vessels in lung relax (decreased PVR) with dramatic increased blood flow and reversal of shunt occurs through ductus arteriosus leading to increased left atrial pressure resulting in functional closure of foramen ovale.
- If this transition does not happen smoothly then infant could present with irregular respiratory effort, tachypnea, respiratory depression with apnea, bradycardia, tachycardia, hypotonia, low oxygen saturation, persistent cyanosis, or hypotension.
PREPARING FOR RESUSCITATION
Resuscitation Team
- Every birth should be attended by at least one individual trained in neonatal resuscitation.
- In case of presence of any of the risk factors (Table 1), minimum two qualified persons should attend the resuscitation.
- The number and qualifications of personnel will increase if higher risk such as an extremely premature birth or high likelihood for extensive resuscitation such as cord prolapse is present. Always identify need for additional help.
Behavioral Skills
Behavioral skills which are key to resuscitation include anticipated preparation, prebriefing, effective communication, assumed leadership role, delegation of roles, proper documentation, and identification of additional help and resources. The role of effective communication is extremely essential.
Four Prebirth Questions
- At every delivery, following four prebirth questions should be asked to the obstetrics care provider:3
- Expected gestational age
- Amniotic fluid clear or not
- Number of babies expected
- Any other additional risk factors.
- Importance of prenatal counseling in the presence of risk factors is also pertinent for improved resuscitation.
Delayed Cord Clamping
- Current evidence suggests delayed cord clamping (DCC) for at least 30–60 seconds is beneficial for vigorous term and preterm newborns.
- Delayed cord clamping is not performed in cases of maternal hemorrhage, placental abruption, bleeding placenta previa, bleeding vasa previa, uterine rupture, cord avulsion, 4severe intrauterine growth restriction (IUGR) with abnormal cord Doppler studies, suspected twin-to-twin transfusion, hydrops, severe chromosomal, or structural anomalies.
- Benefits include improved transitional circulation hemoglobin levels, improved iron stores, decreased need for blood transfusions, lower incidence of necrotizing enterocolitis, intraventricular hemorrhage (IVH), and neurodevelopmental outcome.
INITIAL STEPS OF NEWBORN CARE
Evaluation at Birth (Neonatal Resuscitation Program Algorithm—Flowchart 1)
- All neonates should have a prompt evaluation at birth on three questions to decide if they can stay with their mother for transition or moved under warmer for further assessment and initial steps.
- Does the baby appear to be term?
- Does the baby have good muscle tone?
- Is the baby breathing or crying?
- If answer to all three is yes, then baby can transition to skin-to-skin care with the mother (routine care). If answer to any of the questions is NO, one should move the baby under radiant warmer and perform initial steps of resuscitation.
Initial Steps
- Providing warmth: Place the baby under radiant warmer. For preterm infants <32 weeks, additional warming methods like thermal blanket, covering the head with a hat and placing a plastic wrap over the body without drying can be used. Maintaining the temperature between 36.5°C and 37.5°C in the delivery room is associated with better perinatal outcome.
- Position the head and neck to open the airway: Slightly extend the head in sniffing position to open the airways and allow unrestricted air entry. One may place a small rolled towel under the baby's shoulder.
- Clear airway (if necessary): Clear secretions, if baby is not breathing/gasping/has poor tone/secretions are obstructing the airways or when positive pressure ventilation (PPV) is anticipated. Suction only when visible secretions are present. Suction pressure should not exceed 80–100 mm Hg. Suction mouth before nose (remember M comes before N). Routine tracheal suction is no longer recommended for nonvigorous babies with meconium stained fluid.
- Dry: The baby should be thoroughly dried to decrease evaporative heat loss and wet linen should be discarded. Preterm infants <32 weeks should be covered immediately in a polyethylene plastic to decrease heat loss.
- Stimulate: The initial steps provided so far will frequently provide enough stimulation for the baby to breathe. If the newborn does not have adequate respiration, providing brief stimulation by gently rubbing of back, trunk or extremities will stimulate breathing. One should begin PPV immediately if the newborn remains apneic despite brief stimulation. Vigorous use of tactile stimulation in a baby, who is not breathing, wastes valuable time.
POSITIVE PRESSURE VENTILATION
The most important effective action in resuscitating a compromised newborn is assisted ventilation.5
Indication
- After initial steps of resuscitation, if the baby is apneic or gasping or has HR <100 beats/min, PPV should be started.
- Additional indication is if baby is breathing and has HR >100 beats/min but baby is not maintaining saturations in target range despite free flow oxygen or continuous positive airway pressure (CPAP).
Whenever indicated, it should be started within 1 minute of birth called the golden minute.
Pulse oximeter should be placed on right wrist (preductal). Probe is attached first to hand and then cable is attached to monitor for better signal acquisition.
Self-inflating Bag
- Unless squeezed, a self-inflating bag remains in a fully expanded state. It recoils and re-expands drawing fresh air on its release. When the bag is connected to a source of oxygen, it gets filled with the gas that depends on the supplied oxygen concentration. In case an oxygen source is not attached to the bag, it gets refilled by drawing room air (21% oxygen).
- Because of its self-inflating nature, there is no need of compressed gas or a tight seal at the outlet to keep it inflated.
- The rate of ventilation is decided by how frequently you squeeze the bag and the inspiratory time (IT) is determined by the duration of the squeeze. Peak inspiratory pressure (PIP) is controlled by how hard the bag is squeezed. Positive end expiratory pressure (PEEP) cannot be delivered unless an accessory PEEP valve is attached.
- Because gas only flows out of the mask when the bag is being squeezed, a self-inflating bag cannot be used to administer CPAP or free-flow oxygen. It is possible to administer free-flow oxygen in some self-inflating bags through the open reservoir (“tail”) on them.
- To limit the peak inflating pressure, there is a pressure-release valve, also called a pop-off valve in most self-inflating bags. The limiting pressure in these valves is usually set at 30–40 cm H2O pressure beyond which they are released.However, at times, they may not be very reliable and may not release until higher pressures are achieved. In some self-inflating bags, the pressure-release valve can be temporarily occluded, to allow higher pressures to be delivered.
- It can be used even in the absence of compressed air or oxygen source.
Flow-inflating Bag
- It requires source of compressed gas and gets inflated only when the gas is flowing into it and the outlet is sealed, such as when the mask is tightly applied to a baby's face. In the 8absence of a compressed gas source or improper seal, the bag will collapse and look like a deflated balloon. In case the bag fails to inflate or gets partially inflated, it indicates that the seal is not tight.
- The ventilation rate will depend on how many times one squeezes the bag and how fast is the bag squeezed and released will determine the IT. PIP is controlled by how hard the bag is squeezed to ensure that the appropriate pressure is used. To measure the delivered PIP, one should use a manometer with a self-inflating or a flow-inflating bag.
- Can be used to deliver 100% free-flow oxygen.
- Positive end expiratory pressure is adjusted using a flow control valve adjustment.
- Cannot be used outside the setting of delivery room as it fills only when compressed air flows into it.
- Needs practice and the importance of a good seal is extremely important for use for this device.
T-piece Resuscitator
- It is a mechanical device that uses valves to regulate the compressed gas flowing toward the patient. A compressed gas source is needed for this device.
- A finger is used to alternately occlude and release an opening on the top of the T-piece cap to deliver a breath. On occlusion of the opening, gas flows through the device toward the baby and on releasing the opening, some gas will escape through the cap.
- The ventilation rate will depend on how often the opening on the cap is occluded and how long the cap is occluded will decide the IT.
- Peak inspiratory pressure during each assisted breath is limited by the inspiratory pressure control.
- To prevent inadvertent delivery of PIP beyond predetermined preset value, the device has a maximum pressure relief control.
- Inspiratory and expiratory pressure are measured by a built-in manometer. Hence PEEP and free-flow oxygen can be given and a predetermined consistent PIP can be provided to prevent over inflation.
- Disadvantage of the device is that it cannot be used outside the delivery room setting.
Important Considerations during PPV
- Indicators of successful PPV are rising HR, chest rise, bilateral breath sounds, and improvement in oxygen saturation.
- Effective seal with the mask is one of the key elements missed. Mask should be applied on the face such that the pointed edge is over the nose and mask covers the mouth and nose and the tip of the chin rests within the rim of the mask. The thumb and the index fingers encircle the rim of the mask and the other three fingers are snugly placed under the bony angle of the jaw to gently lift the jaw upward toward the mask. When the correct position of the mask is ensured, one should apply even downward pressure on the rim of the mask to obtain an airtight seal with the head held in sniffing position. In a large baby, it may be difficult to achieve a correct head position and a good seal using one hand. In such a scenario, one can use both hands to hold the mask with the jaw thrust technique by gently lifting the jaw toward the mask.
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- Initial PIP settings of 20–25 cm H2O should be used. In some infants, this may need to be increased up to 30–40 cm H2O for opening up alveoli.
- Initial PEEP should be set at 5 cm H2O.
- FiO2 setting: For the initial resuscitation of newborns greater than or equal to 35 weeks’ gestation, set the blender to 21% oxygen. For the initial resuscitation of newborns less than 35 weeks’ gestation, set the blender to 21–30% oxygen.
- PPV is stopped: When HR is >100 beats/min and baby has sustained spontaneous breaths.
- Ventilation corrective steps: When PPV is ineffective, one needs to take ventilation corrective steps (Table 2).
The assistant needs to tap out the HR and also say out if HR is improving or getting worse. HR is counted for 6 seconds and multiplied by 10 to give an approximate HR. After prolonged PPV, consider inserting an orogastric (OG) 8 F feeding tube and 20 mL syringe measured by the distance between bridge of the nose to the earlobe to the point midway between xiphoid and umbilicus.
CHEST COMPRESSION
- Indications for chest compressions: When HR remains <60 beats/min despite 30 seconds of effective PPV.
- Considerations during chest compressions:
- Application of electrocardiogram (ECG) leads if available.
- Intubation if not done so far.
- Increase oxygen concentration to 100% FiO2.
- Coordination with PPV.
- Preparing for placement of umbilical venous (UV) line.
- Methods of chest compression: There are two methods—(1) thumb technique and (2) two-finger technique. In thumb technique, two thumbs are used to depress the sternum while hands encircle the torso and finger supports the spine. This is the preferred technique as it is superior in generating peak systolic and coronal perfusion pressure. Two-finger technique where the tips of the middle and index fingers are used to compress the sternum 10perpendicularly. Pressure is applied to the lower third of the sternum and sternum is depressed to a depth of approximately one-third of antero-posterior (AP) chest diameter. The thumbs/tip of fingers should remain in contact with the chest during both compression and release.
- Timing of chest compression: Coordinated by counting loud “one and two and three and breathe and...” Each 2-second cycle of events comprises three compressions and one ventilation in 2 seconds [a total of 120 events—90 compression and 30 breaths (3:1) in 60 seconds; Ratio of 3:1]. Wait for 45–60 seconds and then assess HR again.
- Indications to stop chest compression: If HR is ≥60 beats/min, stop chest compressions and continue PPV with 40–60 breaths per minute.
INTUBATION
- Indication for intubation: Endotracheal intubation is considered when PPV with face mask is not resulting in clinical improvement or lasts more than few minutes, when chest compressions are needed and for reliable airway access in special situations such as need for surfactant, suspected congenital diaphragmatic hernia (CDH) or direct tracheal suction if the airway is obstructed with thick secretions.
- Intubation procedure: Determine size of endotracheal tube (ET), position the baby in sniffing position, ask for neck roll if needed, check light of the laryngoscope, hold the laryngoscope with left hand, use the stylet in tube if needed, insert tube to length of weight in kilograms + 6 or nasal-tragus length + 1, request/apply cricoid pressure if needed, and pass the tube into glottis beyond the markings on the tube. Stabilize ET tube against the hard palate and tape the tube.
- Time to intubate: Not more than 30 seconds for each trial.
- Assessment of successful intratracheal intubation: The operator watches tube pass through cords, symmetric adequate chest rise, bilateral breath sounds, increasing HR and improving saturations, mist in tube, change in colorimetric CO2 detector from purple to yellow, and decreased or absent breath sounds over the stomach. Confirm with chest X-ray, if available, checking also for tube position and pneumothorax. Babies with poor cardiac output and extremely low birth weight (ELBW) babies may take time to show reliable color change. If epinephrine is given through ET tube it could falsely turn the color yellow.
- Laryngeal mask airway (LMA): May be used if PPV is ineffective and intubation is not feasible. Other indications include congenital anomalies involving mouth, lip, palate, tongue, neck, jaw, Pierre Robin sequence, and trisomy 21. Use size 1 for neonates. For insertion of LMA, position baby in sniffing, hold device like a pen and advance with the opening facing away from the operator. Inflate with 2–4 mL of air (Fig. 5).
MEDICATION
Epinephrine
- Indication: When HR is <60 beats/min after 30 seconds of effective ventilation and another 60 seconds of coordinated chest compression and effective ventilation.
- Dose: Epinephrine 1:10,000 solution 0.1–0.3 mL/kg IV (given rapidly followed by a flush of 0.5–1 mL normal saline) and 0.5–1 mL/kg endotracheally.11After epinephrine check HR in 1 minute and continue chest compressions and PPV with 100% oxygen. If HR is still less than 60 beats/min, repeat the dose of epinephrine every 3–5 minutes.
- Volume expanders: Volume expanders are indicated if the baby is not responding to the steps of resuscitation and has signs of shock or a history of acute blood loss. The recommended solution for treating hypovolemia is 0.9% NaCl (10 mL/kg normal saline). In case of severe fetal anemia one can use type-O Rh-negative blood (10 mL/kg). This can be given over 5–10 minutes and pausing to give the epinephrine flushes as needed if chest compressions are being done. Ringer's lactate is no longer recommended for treating hypovolemia.
SPECIAL SITUATIONS
If HR <60 beats/min in spite of effective ventilation, consider hypotension, pneumothorax, and other structural reasons like airway malformation, hydrops, abdominal ascites, CDH, pulmonary hypoplasia, chromosomal defects, metabolic acidosis, hypoxic-ischemic encephalopathy (HIE) or congenital heart disease (CHD).
- In prenatally diagnosed CDH, minimize face mask ventilation, perform early planned intubation, and use OG tube for gastric decompression.
- For pneumothorax/chylothorax/pleural effusion needle decompression at bedside if needed.
- For pulmonary hypoplasia and hydrops, higher PIPs need to be considered for adequate chest movement.
AFTER RESUSCITATION
- At the end of each resuscitation, it is important to debrief. Discuss briefly what went well during the resuscitation, was the leader effective and delegated tasks well, and was there good communication and team work, what was not done well, what could have been done better to improve. The goal is not to assign blame but to improve the process.
- Reasons to stop resuscitation: Resuscitation may be discontinued after 10 minutes of asystole, after maximal resuscitation effort.
1. Baby is born limp and apneic. You place her under radiant warmer, position her airway, remove secretions, dry and stimulate her. If she remains still apneic, next step is to:
- Provide positive pressure ventilation
- Provide free-flow oxygen
- Consider CPAP
2. What should be size of endotracheal tube for a baby weighing <1,000 g?
- 2.0 mm
- 2.5 mm
- 3.0 mm
- 3.5 mm
3. Ratio of chest compression to ventilation is:
- 1:3
- 3:1
- 5:2
- 2:5
4. Which of the following devices provide PEEP during resuscitation (more than one may be true)?
- Self-inflating bag
- T-piece resuscitator
- Flow-inflating bag