The ill neonate is a frightening entity for most emergency clinicians. Neonates are a rare entity at many nonpediatric emergency departments (EDs), and when they are brought in, it is frequently for minor complaints.2 When critically ill infants do present, appropriate newborn resuscitation equipment and consultations are often unavailable.3,4 Even when a general pediatric consultation is readily available, the experience with ill children may be limited. One study of academic pediatric training programs indicated that only 36% of graduating residents had led a pediatric resuscitation, and a handful had no pediatric advanced life support (PALS) training.5 It is easy to understand why the resuscitation of a neonate can be an intimidating and lonely experience for an emergency clinician.
This issue of Pediatric Emergency Medicine Practice will discuss recognition of the causes as well as general and disease-specific means of stabilizing the critically ill neonatal patient. There are many rare diseases that can cause shock in a neonate. This article will concentrate on some of the most common: sepsis/serious bacterial infections (SBIs), including meningitis, bacteremia, and urinary tract infection; malrotation; necrotizing enterocolitis (NEC); ductal-dependant cardiac lesions, including cyanotic congenital heart disease and ductal-dependent obstructive lesions; inborn errors of metabolism (IEMs) that present with significant metabolic derangement in the neonatal period (specifically, urea cycle defects and organic acidemias); salt-wasting types of congenital adrenal hyperplasia (CAH); and nonaccidental trauma (NAT).
A 5-day-old boy is brought into the emergency department for poor feeding and lethargy. The patient is the full-term product of a vaginal delivery to a healthy mother who received routine prenatal care. He had been eating well—2 oz of formula every 2 hours—until today, when he began sucking poorly and taking less than half an ounce with each feeding. He has been afebrile, and the review of his systems is otherwise negative. On examination, the baby is notably difficult to arouse. He appears slightly jaundiced and mottled, which the mother believes are new findings. His temperature is low at 35.5ºC (95.9ºF), his heart rate is 190 beats per minute, his respiratory rate is 50 breaths per minute, and his blood pressure reading is 66/38 mm Hg. His anterior fontanel is open and flat, his lungs are clear, the cardiac examination reveals significant tachycardia, the liver is palpable 1 cm below the costal margin, results of the abdominal examination are unremarkable, and the capillary refill time is poor at 5 seconds. It has been some time since you reviewed the differential diagnosis of the ill neonate, but you recall the mnemonic THE MISFITS and generate an extensive list: trauma, heart disease, electrolyte disturbances, metabolic, inborn errors, sepsis, formula mishaps, intestinal catastrophes, toxins, and seizures.1 You have pediatric colleagues available, but this newborn looks like he needs some intervention before they are likely to return your page. Where should you start with the resuscitation? If little blood is available, what are the high-yield laboratory tests? What if the nurses can't obtain access in this critical patient? And what illnesses are most likely (ie, to help you establish a diagnosis and start disease-specific treatment as quickly as possible)?
Neonatal mortality information was derived from the National Vital Statistic System maintained by the Centers for Disease Control and Prevention. This is a national reporting database. Small prospective studies on the incidence and test characteristics of neonatal sepsis were also available.
Each of the diseases discussed in this article is an uncommon entity, and the diagnosis and treatment is generally based on extrapolation from pathophysiology, expert opinion, and small retrospective data sets. A large prospective study was available on treatment of IEMs and optimal antibiotic therapy for the infected neonate. A well-researched literature review resulting in national guidelines was available regarding screening for congenital heart disease and treatment of neonatal sepsis. Small prospective studies were done on the association between SBIs and apparent life-threatening events (ALTEs). The remainder of the studies used in this paper consisted of retrospective case series.
PubMed® and Ovid MEDLINE® were searched for literature on neonatal emergencies published from 1950 to the present. Multiple search terms were used because of the variety of conditions discussed. Pertinent abstracts were used for non-English language studies.
Evidence-based medicine requires a critical appraisal of the literature based upon study methodology and number of subjects. Not all references are equally robust. The findings of a large, prospective, randomized, and blinded trial should carry more weight than a case report.