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The Neonatal Airway and the Goldilocks Phenomenon

2017; Elsevier BV; Volume: 69; Issue: 2 Linguagem: Inglês

10.1016/j.annemergmed.2016.12.021

1097-6760

Paul Jhun, Katrina Jhun, Dan Wei, Mel Herbert,

Pleural and Pulmonary Diseases

SEE RELATED ARTICLE, P. 166. An 11-month-old female infant presented to the emergency department (ED) after referral from her pediatrician’s office for acute respiratory distress for the past 15 hours. On arrival, the child appeared lethargic and in moderate respiratory distress. Physical examination demonstrated tachypnea with decreased breath sounds on the left and a room air pulse oximetry of 85%. A 2-view chest radiograph showed marked displacement of the mediastinum to the right. Diagnosis? Tension gastrothorax resulting from herniation through a previously undiagnosed diaphragmatic hernia.1Miranda J. Collins B. Wydro G. Garg M. Infant with acute respiratory distress.Ann Emerg Med. 2017; 69: 166Abstract Full Text Full Text PDF PubMed Scopus (1) Google Scholar Whoa. Deep breath. Underwear check. If you’re wondering whether or not the provider needle-decompressed this kid’s stomach, he didn’t. Miraculously, a little supplemental oxygen and a nasogastric tube stabilized the kid enough to make it to a higher level of care. Holy smokes, talk about dodging a hot mess! Congenital diaphragmatic hernias scare even your friendly neighborhood neonatologist, and for good reason: they typically develop in utero, and guess what that hernial pooch into the lung space does to the lung? Lungs can’t develop, leading to pulmonary hypoplasia, which may result in persistent pulmonary hypertension of the newborn and wacky physiology from minute 0 of life.2Bloss R.S. Aranda J.V. Beardmore H.E. Congenital diaphragmatic hernia: pathophysiology and pharmacologic support.Surgery. 1981; 89: 518-524PubMed Google Scholar But such hernias are pretty rare,3McGivern M.R. Best K.E. Rankin J. et al.Epidemiology of congenital diaphragmatic hernia in Europe: a register-based study.Arch Dis Child Fetal Neonatal Ed. 2015; 100: F137Crossref PubMed Scopus (179) Google Scholar so we thought we’d talk about something more clinically practical but equally scary: the newborn airway. Newborns delivered in the ED come in 2 flavors: aw and ugh. The former involves cooing staff and crying parents. The latter…well, it certainly involves a lot of crying. I think we all have enough of an imagination to picture how that cluster unfolds. Dry, stimulate, warm, bulb suction…stimulate…stimulate… Um, why is this kid not crying and breathing? Now, before we dive into newborn airways, it’s worth mentioning and reviewing our update of the 2015 American Heart Association neonatal resuscitation guidelines4Wyckoff M.H. Aziz K. Escobedo M.B. et al.Part 13: neonatal resuscitation: 2015 American Heart Association guidelines update for cardiopulmonary resuscitation and emergency cardiovascular care.Circulation. 2015; 132: S543-S560Crossref PubMed Scopus (525) Google Scholar in the September 2016 issue of the EM:RAP audio podcast,5Claudius I, Behar S, Nicholas C. AHA neonatal guideline updates. Emergency medicine: reviews and perspectives. 2015. Available at: https://www.emrap.org/episode/thereturn/pediatricpearls1. Accessed December 9, 2016.Google Scholar in which we share some great pearls. The very first questions you should be asking yourself as the baby comes out are “Is the baby term?” “Does the baby have good tone?” “Is the baby breathing or crying?” If the answer to all 3 questions is yes, then you can generally stop manhandling the baby and hand it over to Mom for that kangaroo thing. But not every birth has a happy beginning, and we asked our friendly neighborhood neonatologists to share with us some clinical pearls to help avoid some embarrassing and potentially serious complications they've seen happen at the hands of emergency providers managing the newborn airway. In emergency medicine, “intravenous line, oxygen, monitor, airway equipment at the bedside” is our mantra. When we see cyanosis or an oxygen saturation less than 90%, we’ve been trained like ninjas to reflexively reach for the oxygen. Remember, though, that the typical newborn does not come out looking like the Gerber baby, with pink rosy cheeks. They’ve been breeding like an alien inside a warm, gooey sac for months, with their lungs filled with amniotic fluid. The only oxygen they’ve seen was dissolved in blood. Know that every baby comes out of the womb some shade of blue. And, when you connect the pulse oximetry, know that 60% on room air is normal in the first minute of life; think twice before you reflexively slap on supplemental oxygen. Oxygen is a medicine and you need it to use it wisely. Prolonged hyperoxia and the resulting oxygen free radicals may cause organ injury.6Rabi Y. Rabi D. Yee W. Room air resuscitation of the depressed newborn: a systematic review and meta-analysis.Resuscitation. 2007; 72: 353-363Abstract Full Text Full Text PDF PubMed Scopus (165) Google Scholar Pro tip: Take a picture of the Table. Even better, print and tape it permanently to your neonatal resuscitation warmer (Figure 1). Lately, the phrase “cognitive off-loading” has been popping up frequently in medical education, and for good reason. Simple numbers and basic arithmetic magically become calculus when you have a blue baby in your hands and the parents stare at you…then the baby…and then back to you, all the while wondering why their child doesn’t look like the ones in the pregnancy class brochures.TableTargeted preductal oxygen saturation after birth.4Wyckoff M.H. Aziz K. Escobedo M.B. et al.Part 13: neonatal resuscitation: 2015 American Heart Association guidelines update for cardiopulmonary resuscitation and emergency cardiovascular care.Circulation. 2015; 132: S543-S560Crossref PubMed Scopus (525) Google ScholarMinutesSaturation, %160–65265–70370–75475–80580–851085–95 Open table in a new tab Just for the record, noninvasive positive-pressure ventilation is almost always the first go-to strategy for positive-pressure ventilation in an apneic or gasping newborn.4Wyckoff M.H. Aziz K. Escobedo M.B. et al.Part 13: neonatal resuscitation: 2015 American Heart Association guidelines update for cardiopulmonary resuscitation and emergency cardiovascular care.Circulation. 2015; 132: S543-S560Crossref PubMed Scopus (525) Google Scholar Although some of us yearn for that high-5 moment after a successful intubation, remember that you can often use a bag-valve-mask device for an extended period, turn babies’ situation around, and avoid the stress of dealing with endotracheal tubes (ETTs) the size of straws and laryngoscopes the length of your pinky. Pro tip: The natural tendency when using a face mask is to push it against the patient’s face to create a good seal. But remember that newborn babies are obligate nose breathers and their itty bitty noses aren’t as stiff as adult ones. Applying too much pressure causes obstruction of the airway (talk about being counterproductive). Oh, did we mention that good oral and nasal suctioning will go a long way? But let’s say the decision is made to intubate the newborn airway. Now, you might be thinking to yourself, do I use rapid sequence intubation? Do I need to put in an umbilical line? Keep it simple. You’re a big, strong person up against a tiny, feeble newborn. If you’re going down the intubation route, chances are the baby’s not going to gum your fingers off. So stop with the succinylcholine or rocuronium debate and just tube it. If the vocal cords are moving, you can time the tube passage to when the cords open up. Worst case, push through the cords. Ideally, another provider is simultaneously working on peripheral or central venous access and getting your medications while you’re intubating. As a solo provider, though, remember that the majority of neonatal resuscitation is respiratory in origin, not cardiac.4Wyckoff M.H. Aziz K. Escobedo M.B. et al.Part 13: neonatal resuscitation: 2015 American Heart Association guidelines update for cardiopulmonary resuscitation and emergency cardiovascular care.Circulation. 2015; 132: S543-S560Crossref PubMed Scopus (525) Google Scholar It all goes back to the ABCs, and oxygenation and ventilation is the ultimate first step before any intravenous fluids or resuscitation medications. So what size blade and ETT do you reach for? That tried-and-true ETT size pediatric equation of (age [in years]/4)+4 doesn't quite work for a baby who is 0 minutes old. And you might think that your pediatric crash cart’s top drawer magically has just what you need. If only that were true. More cognitive overload and decision paralysis. Do you use the 2.5-, 3.0-, or 3.5-mm ETT? Cuffed or uncuffed ETT? Do you use a 00 or 0 or 1 straight blade? Too small a tube and you get leaks. Too big a tube and you risk airway trauma. Too small a blade and you can’t reach the epiglottis. Too big a blade and you can’t fit it in the baby’s mouth. Let’s give Goldilocks some tools to stop futzing around and wasting time, and get to the end of the story faster. Pro tip: Welcome to basic counting: 0-1-2-3. Use a 0 straight blade in a 1- to 2-kg newborn with a 3.0-mm uncuffed tube. Boom. Now you have a reference point. Here's another pro tip: When you hold the blade, use your pinky to provide cricoid pressure and stabilize your hand on the baby’s face (Figure 2). Last pro tip: We’re preaching to the choir when we say that neonates have notoriously anterior vocal cords. Bringing your eyes close to the plane of the baby’s head, whether raising the bed or lowering your body, will make the cords easier to see. Once you pass the tube, how far do you go? You may be tempted to use the “3×ETT size” formula, but when you're working with 1-, 2-, or 3-kg babies, they have significantly different anatomies, and centimeters matter. Pass the tube too far and you right-mainstem that puppy and possibly blow a pneumothorax (trust us, you don't need a nightmare within a nightmare). Don't pass it far enough and you risk dislodging the tube and having the pleasure of reliving your original nightmare. Be the small bear in Goldilocks: not too far and not too shallow; you want it just right. Pro tip: Many neonatologists use the 6+weight (kilograms) or 7-8-9 rule to determine the ETT depth of insertion (in centimeters) from “tip to lip” (tip of the ETT to the patient’s upper lip).7Peterson J. Johnson N. Deakins K. et al.Accuracy of the 7-8-9 rule for endotracheal tube placement in the neonate.J Perinatol. 2006; 26: 333-336Crossref PubMed Scopus (76) Google Scholar Hate math? Put up your hand like you're counting from 1 to 3. One kilogram is 7 cm, 2 kg is 8 cm, and 3 kg is 9 cm (Figure 3). Boom. Here’s another pro tip: After you place the ETT, hold it in place against the hard palate of the baby’s mouth instead of just outside the lip. More likely than not, the newborn you just intubated wasn’t paralyzed, and a quick twist of the head can dislodge your perfectly placed tube. Centimeters…that’s all it takes to separate heroes from zeroes. Once the ETT is secured, we all know that respiratory rate matters. With all the adrenaline pumping through our veins, it’s easy to go Energizer Bunny on the baby with the bag or T-piece. But bag too fast, blow a lung. Bag too slow, hypoxia. Help Goldilocks find that sweet spot, with a target respiratory rate between 40 and 60 breaths/min.4Wyckoff M.H. Aziz K. Escobedo M.B. et al.Part 13: neonatal resuscitation: 2015 American Heart Association guidelines update for cardiopulmonary resuscitation and emergency cardiovascular care.Circulation. 2015; 132: S543-S560Crossref PubMed Scopus (525) Google Scholar The other reason to remember the number 60 is that a pulse rate less than 60 beats/min is an indication for starting chest compressions in a newborn. Pro-tip: You can use the second hand on a watch or the clock on the neonatal resuscitation warmer to make sure you don’t manually ventilate faster than 60 breaths/min. In other words, don’t bag the baby faster than 1 breath/sec. Boom. Drop the mic and walk away. Well, maybe wait until after you sign out that baby to the next provider. The child began receiving supplemental oxygen, and a nasogastric tube was inserted. Oxygenation subsequently improved to 98%. After transfer to a children’s hospital, the child underwent laparoscopic surgery to reduce the herniated bowel and repair the diaphragmatic defect. Infant With Acute Respiratory DistressAnnals of Emergency MedicineVol. 69Issue 2PreviewAn 11-month-old female infant presented to the emergency department after referral from her pediatrician’s office for acute respiratory distress for the past 5 hours. On arrival, the child appeared lethargic and in moderate respiratory distress. Physical examination demonstrated tachypnea with decreased breath sounds on the left and a room air pulse oximetry measurement of 85%. A 2-view chest radiograph showed marked displacement of the mediastinum to the right (Figures 1 and 2). Full-Text PDF