Pediatric Apnea Workup

Updated: Jul 18, 2021
  • Author: Joshua A Rocker, MD; Chief Editor: Kirsten A Bechtel, MD  more...
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Laboratory Studies

According to the AAP Clinical Practice Guidelines, BRUE is a diagnosis of exclusion, and should be applied when there is no apparent etiology after performing an appropriate history and physical. Lower-risk infants should not undergo routine diagnostic testing, and should not be admitted solely for cardio-respiratory monitoring. Higher risk infants are more likely to benefit from diagnostic testing and admissions. History and physical should guide the clinician. 

If the infant is truly afebrile and appears well, laboratory results are likely to be within the reference ranges. In a study looking at patients who presented with apparent life-threatening events (ALTEs), it was demonstrated that only 5.9% came up with a diagnosis with positive testing after a non-contributory history and physical exam. [7]

If the infant does not appear well, the following studies should be considered:

  • Rapid bedside glucose testing, as a decreased glucose level may indicate sepsis or a metabolic derangement. Hypoglycemia can be treated quickly, and if untreated, its consequences can be severely damaging. Therefore, early diagnosis is essential.
  • Complete blood count with differential
  • Blood culture
  • Complete metabolic panel: The combination of  hyperkalemia and  hyponatremia may be the first suggestion of congenital adrenal hyperplasia in the male infant.
  • Arterial blood gas (ABG) or venous blood gas (VBG) measurement
  • Lumbar puncture with culture
  • Urinalysis and urine culture via catheter to obtain the cleanest specimen

Additional studies may include the following:

  • Viral respiratory panel to look for common causes of bronchiolitis such as RSV or  influenza.
  • The tests listed above help in identifying unexplained metabolic acidosis, potential sepsis, or unexplained anemia.
  • When the clinical presentation warrants, tests of the carboxyhemoglobin and methemoglobin level and screening for certain toxins (eg, opiates, benzodiazepines, barbiturates, marijuana, toxic alcohols, botulism) should be considered.

Imaging Studies

In most cases, no imaging studies are needed. In those cases, in which raised intracranial pressure or intracranial injury or hemorrhage due to abusive mechanisms is suspected, CT scanning of the head is suggested as a first line modality; MRI may be more useful for follow up imaging. [32]

In hospitalized premature infants, US of the head may reveal intraventricular and periventricular hemorrhages. [33]

When child abuse is seriously considered, a skeletal survey should be performed.

Chest radiography should be performed in the presence of increased respiratory rate or abnormal findings on lung examination

An echocardiogram should be performed in the case of murmur heard on auscultation, or with a history of concerning for a cardiac etiology such as cyanosis or sweating with feeding.


Other Tests

A neurologist may request an EEG.

An ECG is useful to assess for cardiac arrhythmias or cor pulmonale.

If congenital adrenal hypoplasia is being considered, cortisol and thyroid levels may be measured.

Fiberoptic evaluation of the larynx can be performed if tracheomalacia or laryngomalacia is suspected.