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Neonatal Resuscitation Highlights Author: Geoff Jara-Almonte, MD (PEM Fellow, NY Methodist Hospital) // Edited by: Jennifer Robertson, MD and Alex Koyfman, MD (@EMHighAK) You are midway through an overnight shift in a suburban emergency department (ED) when a young woman is dropped off by her partner in labor. The triage nurse brings her to an exam room and she is placed on the cardiac monitor. Her vital signs are a temperature of 38.5° Celsius (C), a heart rate (HR) of 123, and a blood pressure (BP) of 110 /67 mm Hg.  Between contractions, the patient tells you that this is her 4th pregnancy, is approximately 8 or 9 months pregnant and that she has not had any prenatal care. She also tells you that all of her prior deliveries were “fast”. As you try to decide what to do next, the patient has another contraction and feels an unbearable urge to push.  You see the fetal head at the perineum, and note thick meconium-stained amniotic fluid. You realize that the infant is likely distressed and may require resuscitation.  You try to recall the general priorities of neonatal resuscitation. Most infants transition from intrauterine to extrauterine life without any assistance. The term-infant with good tone, color, and respiratory effort requires no assistance and should be handed off to the mother after birth. However, approximately 10% of infants require some resuscitation and about 1% require extensive resuscitation.[1]   The main priority in neonatal resuscitation is establishment of effective ventilation and oxygenation.  The first step is an initial trial of basic supportive measures including cleaning, drying and stimulating the infant.  If there is poor tone or respiratory effort, try stimulating by gently slapping the feet.  If there is airway obstruction, attempt repositioning – place the infant in the “sniffing” position. If the airway obstruction is due to secretions, attempt gentle suctioning with bulb suction or a soft suction catheter. Heat loss should also be minimized.  Infants should be dried quickly and wet blankets or towels discarded.  Vigorous infants who require no resuscitation should be swaddled in warm dry blankets or placed directly on the mother’s skin.  If resuscitation is required, the infant should be placed in an isolette under a radiant warmer.  Low birth weight infants are at a greater risk of hypothermia.  Those infants less than 1,500 grams (gm) should be wrapped in medical or food grade plastic bag to prevent evaporative cooling. As your nurse pulls out the precipitous delivery pack, you prepare for the delivery by turning on the radiant warmer and connecting the suction and supplemental oxygen. Soon, with a final contraction, a male infant is delivered. You estimate that he weighs about 3.5 kilograms (kg), and appears near term. However, you also notice that he is meconium stained and is cyanotic with minimal respiratory effort.  You realize that this meconium stained neonate is going to require resuscitation. Aspiration of any amount of meconium-stained amniotic fluid, whether intrauterine, intra-partum or post-partum can lead to the development of meconium aspiration syndrome (MAS). Fortunately this syndrome complicates only 2 to 5% of meconium births.  The severity can range from mild tachypnea to severe pneumonitis.  In order to reduce the risk of MAS, older guidelines advocated routine intrapartum suctioning between delivery of the head and shoulders, but this practice has been shown to be ineffective.[2]  Routine intubation and endotracheal suctioning of all infants with thick meconium was historically recommended as well, however this has been shown to be ineffective and is no longer standard practice.[3] Current management of the infant born with meconium-stained amniotic fluid depends on the clinical status of the child.  A vigorous infant can be managed with supportive care and oral and nasal suctioning, if indicated. Non-vigorous infants should have endotracheal suctioning performed prior to other resuscitative measures.  To perform endotracheal suctioning, a meconium aspirator is attached to suction and an endotracheal tube. The infant is then intubated with direct laryngoscopy.  Next, the vent port on the meconium aspirator is occluded and the endotracheal tube is slowly withdrawn.  The used tube is then switched for a clean one, the infant is re-intubated, and the process is repeated.  The procedure is repeated until clear secretions are aspirated.  If there is a significant delay in or difficulty intubating the infant, consider omitting this step and proceeding to positive pressure ventilation (PPV), especially if there is persistent bradycardia. You quickly hook the meconium aspirator to wall suction and attach the other end to the endotracheal tube.  You carefully advance the laryngoscope, lift the epiglottis and see the cords.  You easily pass the tube.  You occlude the suction port on the meconium aspirator and slowly withdraw the tube that contains thick secretions.  You leave the blade in place have your nurse quickly replace the tube and perform a second round of tracheal suctioning.  This time you have only scant secretions in the tube.  You decide that no additional suction is needed. You quickly dry the infant and discard the wet towels. You palpate his pulse at the umbilical stump and note a heart rate of only 50 beats per minute (bpm) and ineffective gasping respirations.  You try and decide what the next step should be. The American Heart Association (AHA) and Neonatal Resuscitation Program (NRP) algorithms allow only 30 seconds to perform the basic supportive measures discussed above. In the case of a non-vigorous meconium-stained infant, basic measures are skipped in favor of immediate endotracheal suctioning. Importantly, bradycardia (HR < 100 bpm) or cyanosis that persists after any step requires the initiation of positive pressure ventilation.  Those infants with adequate respiratory effort and heart rate who remain persistently cyanotic should be given supplemental O2 and placed on the pulse oximetry (SpO2) monitor.  The SpO2 probe should be placed on the right upper extremity to obtain a pre-ductal value. It is usually placed on the thenar eminence.  Placing the probe on the child prior to turning on the monitor may facilitate a more rapid signal acquisition.[4] Controversy exists regarding the concentration of oxygen to use