Pediatric emergency medicine trisk 644

TABLE 96.6 EXAMPLES OF HYPOTONIA AND NEUROMUSCULAR DISEASE Anterior horn cell Motor and sensory neuropathies Neuromuscular junction Congenital myopathy Muscular dystrophy Metabolic and multisystem disease Spinal muscular atrophies Infantile neuronal degeneration Neurogenic arthrogryposis Hypomyelinating neuropathy Charcot–Marie–Tooth disease Hereditary sensory and autonomic neuropathy Acquired transient neonatal myasthenia Congenital myasthenia Infantile botulism Magnesium toxicity Aminoglycoside toxicity Nemaline myopathy Myotubular myopathy Congenital muscular dystrophy Walker–Warburg syndrome Muscle–eye–brain disease Duchenne dystrophy Mitochondrial disorder Peroxisomal disorder Neonatal adrenoleukodystrophy Cerebrohepatorenal syndrome Pompe disease Severe neonatal phosphofructokinase deficiency Severe neonatal phosphorylase deficiency Neonatal Abstinence Syndrome Goals of Treatment It is estimated that over 4% of pregnant women abuse one or more substances during pregnancy—both legal and illicit substances The goals of treatment are to distinguish the infant suffering from neonatal abstinence syndrome (NAS) and acute intoxication, and to assess the safety of the infant’s current home environment First-line treatment for infants with abstinence syndrome is supportive care and decreased stimulation Available pharmacotherapy is dependent on the class of drug the infant was exposed to in utero Infants that present with seizures respond well to anticonvulsant therapy, however, these infants should have a broad diagnostic evaluation for seizure etiology, including infection, metabolic derangements, and CNS hemorrhage CLINICAL PEARLS AND PITFALLS The age of presentation for infants with NAS can vary from several hours to several weeks after birth, depending on the exposed substance Naloxone administration to chronically opioid-exposed neonates is contraindicated as it may precipitate severe withdrawal and/or seizures Opioids Infants with opiate withdrawal may present with sleep–wake abnormalities, feeding difficulties, irritability, or weight loss In extreme cases, up to 10% of infants will also present with seizures Common opioid exposures during pregnancy may include morphine (and its derivatives), heroin, methadone, and buprenorphine Sixty percent to 80% of infants exposed to heroin or methadone will develop signs of NAS Higher doses of maternal methadone are more likely to result in NAS The onset of withdrawal is most often in the first to days after birth, although can present as late as weeks of age Pharmacotherapy for opioid withdrawal includes opiates (oral or intravenous morphine), barbiturates (phenobarbital), and benzodiazepines (diazepam) Opiate treatment can decrease the incidence of seizure, reduce time to regain birth weight, and decrease the incidence of treatment failure More recent reports using clonidine have been promising in the treatment of opioid withdrawal, although larger, more detailed pharmacokinetic studies are warranted Cocaine Cocaine use in pregnancy increases the risk of intrauterine demise, placental abruption, hypoxia–ischemia, and growth restriction of the developing fetus Early exposure may also be associated with congenital anomalies, though a distinct syndrome has not been described These children may have abnormalities in state regulation, autonomic regulation, and reflexes at to weeks postpartum, although they not have typical neonatal withdrawal symptoms If present, the intensity and duration of symptoms are much shorter than in opioid-exposed infants Most importantly, these infants should be evaluated for additional substance exposure, as many pregnant women using cocaine may also demonstrate polysubstance use Amphetamines The effects of amphetamine and methamphetamine use are similar to cocaine, acting as a CNS stimulant, but with a longer duration of action There is a similarly increased risk of miscarriage, prematurity, growth restriction, and placental abruption Infants may present with disturbances in state regulation and sleep, as well as feeding disturbances, hypertonia, and tremors Marijuana The effects of marijuana, and specifically tetrahydrocannabinol (THC) are dose dependent Infants with higher intrauterine exposure are more likely to present with lethargy, hypotonia, and decreased responses to stimuli Infants may exhibit increased startle reflexes or tremors Infants rarely present with typical symptoms of NAS, although long-term studies are lacking Selective Serotonin Reuptake Inhibitors There has been increased use of antidepressants in pregnancy over the last decade, particularly the use of selective serotonin reuptake inhibitors Emerging literature suggests prenatal SSRI exposure may result in infant withdrawal symptoms of altered state regulation and autonomic reactivity There have been reports of more serious reactions, such as tachycardia and cyanosis Symptoms appear to be self-limited, and current therapy is largely supportive, although longterm studies regarding the safety of SSRI use in pregnancy are still warranted Abnormal Tone Hypotonia in the neonate can interfere with adequate oral intake, and in progressive or severe forms, may impede normal respiratory function These infants may present with failure to thrive, respiratory distress and impending respiratory failure, aspiration pneumonia, apnea, including sleep apnea, or apparent life-threatening events (ALTEs) The goals of treatment are to stabilize the infant with supportive care, including intubation and assisted ventilation when appropriate, and then initiating the diagnostic evaluation for the low tone (see Table 96.5 ) The differential for hypotonia is quite broad and extends beyond neurologic disorders Systemic illness, including infections, endocrine disorders, such as congenital hypothyroidism, and genetic disorders, such as Prader–Willi, all may present with hypotonia The hypotonic infant can be identified by low resting tone—the classic “froglike” position with abnormal extension of the limbs —as well as exaggerated head lag when pulled to sit Central hypotonia can be identified when there is excessive “slip-through” at the shoulder girdle when the infant is held in vertical suspension, or when the limbs and head hang low on horizontal suspension While the hypertonic infant is an abnormal neurologic finding and should be referred to a specialist, it rarely presents as an emergency Exceptions include neonatal tetanus and advanced staged kernicterus, with hypertonic extension of the extremities, retrocollis, and opisthotonus NEONATAL INFECTIONS Goals of Treatment Neonatal infection and neonatal sepsis are among the most common diagnoses encountered in the emergency room The immature immune system makes newborns very susceptible to infection resulting in more severe manifestations than older children or adults Neonatal infections often have nonspecific presentations Neonatal sepsis should be included in any differential diagnosis in a symptomatic neonate Rapid evaluation and management of acute deterioration is the initial goal of therapy Obtaining the necessary cultures and diagnostic testing and coverage with broad-spectrum antibiotics is the main priority Symptomatic neonates should be admitted for close observation due to the likelihood of progression Treatment is then tailored to the specific pathogen once it has been identified Treatment in the ED is aimed at cardiorespiratory stabilization and rapid initiation of antibiotic therapy to prevent acute deterioration KEY POINTS ... an abnormal neurologic finding and should be referred to a specialist, it rarely presents as an emergency Exceptions include neonatal tetanus and advanced staged kernicterus, with hypertonic extension... Treatment Neonatal infection and neonatal sepsis are among the most common diagnoses encountered in the emergency room The immature immune system makes newborns very susceptible to infection resulting