Objectives

• Define the pathophysiologic variables present in the infant or child presenting with altered mental status
• Provide a broad differential diagnosis for an infant or child presenting with altered mental status.
• Describe the initial approach to identifying an infant or child with altered mental status.
  

Case Study

A 3 year old male presents through triage in the care of his grandmother with concerns of excessive sleepiness. Prior to presentation, the child was found sleeping on the bathroom floor next to an open pill organizer. After several minutes of attempts to wake the child up, the grandmother, who lives 3 blocks from the hospital, placed her grandson in the car and drove him directly to the Emergency Department.

The grandmother states that she watches the child 3 times weekly while her daughter works.The child was out of the grandmother’s direct line of sight for less than 5 minutes while she prepared lunch. The child has no prior medical history and she is unaware of any recent illness.  She does not suspect any trauma associated with her grandson’s sleepiness. The child is placed in a treatment room and you are called, emergently, to the bedside. At the time of first contact, you note the patient to appear pale, diaphoretic, and with a slower than expected rate of breathing.

Altered Mental Status

Altered mental status in the pediatric patient represents a symptom of decompensated acute or chronic injury or illness. It may evolve slowly over days to months as in the case of an expanding intracranial mass, or rapidly in the course of seconds, minutes, or hours as in the case of acute blood loss secondary to trauma. Identification of the underlying pathologic process requires an understanding of the pathophysiologic cause of altered levels of consciousness, knowledge of normal and abnormal vital signs, and familiarity with a broad differential diagnosis. In clinical terms, a patient’s level of consciousness can be defined as a measurement of arousal and responsiveness to stimulus in the environment. It is controlled by two major components of the central nervous system.  The reticular activating system (RAS), residing in the brainstem, primarily controls the sleep-wake cycle and levels of wakefulness.  The second component includes the two hemispheres of the cerebral cortex; they are generally responsible for higher executive function and purposeful response to sensory input or environmental stimulus. Injury to the brainstem, to the cerebral cortex, or to both, will result in an altered level of consciousness ranging from mild lethargy to profound coma. Signs and symptoms during the initial onset may be subtle and difficult to detect thus requiring a high index of suspicion, a firm understanding of developmental differences among different age groups, and a practical approach to the evaluation of a child with altered mental status.

Clinical Approach

The pediatric assessment triangle  (PAT) provides a quick observational method to assess mental status and physiologic abnormality of a presenting patient. It includes components of appearance, work of breathing, and circulation that allow a rapid assessment of patient well-being and stability. The clinician need only several seconds to observe these characteristics. The ultimate goal of the PAT is to determine “stable versus unstable” (3) hence the need for immediate intervention and stabilization.

A wealth of information can be gained by the general appearance of a child. Salient features of a child’s appearance, regardless of age, may be categorized by the mnemonic TICLS (3):

TICLS 

The general appearance of a patient in terms of the TICLS mnemonic will indicate the adequacy or inadequacy of physiologic homeostasis and the maintenance of appropriate functioning of the RAS and cerebral hemispheres as discussed earlier.

Vital Signs

Identification of an infant or child with altered mental status is arguably one of the more challenging presentations encountered in the Acute Care and/or Emergency Department settings. To make the diagnosis, a competent clinician is required to maintain a persistently high index of suspicion in combination with the requisite knowledge of physiologic and pathophysiologic age differences unique to the pediatric patient. Early deviations from normal vital sign parameters may provide subtle clues to the diagnosis and etiology of altered levels of mentation.

Understanding the unique and essential differences in the pediatric patient is essential to the identification of the patient presenting with altered mental status. The fundamental cornerstone includes a firm knowledge and understanding of age appropriate vital signs. (1, 2)

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Differential Diagnosis

The well accepted mnemonic AEIOU TIPS offers a comprehensive, logical start point to develop and refine a differential diagnosis for causes of altered mental status in the pediatric patient.   

Formulation and prioritization of a broad differential diagnosis as offered by AEIOU TIPSwill provide the clinician a vital start point with which to tailor immediate life saving intervention (airway management, CPR, fluid resuscitation) and will also serve as the necessary framework to formulate a practical and guided diagnostic workup.

While an in depth discussion of emergent and urgent intervention is beyond the scope of this discussion, a practical and organized approach of child with altered mental status is vital to the identification, workup, and treatment of the underlying pathologic and often life threatening etiology.

Case Study Resolution

As noted previously, you’ve observed  the essential categories of the pediatric assessment triangle (PAT) and rapidly identify the patient as critically ill.  At that time, nursing staff reports the child’s first set of vital signs as they place the patient on continuous monitors as you have requested.

Heart Rate 78, Respiratory Rate 22, and Blood Pressure 78 systolic

The patient is placed on supplemental oxygen and a point of care glucose is obtained.  You formulate a differential diagnosis based on the limited history provided by the grandmother who remains appropriately concerned and close to the patient’s bedside.  You ask a few follow up questions and discover that the patient’s grandmother has a longstanding history of type 2 diabetes and hyperlipidemia.  She currently takes Metformin, Glucophage, and Lipitor daily.   The nursing staff alerts you that the glucose level of the patient is 32.  You order a weight-based dose of D-25 (Dextrose 25%) intravenously to which the patient awakens and begins to vigorously cry.  Heart/respiratory rates and blood pressure normalize.  You preform a full physical assessment, order a baseline metabolic panel, and admit the patient in stable condition to the PICU with the working diagnosis of accidental sulfonyurea ingestion.

References

1. Fleming S, Thompson M, Stevens R, et al. Normal ranges of heart rate and respiratory rate in children from birth to 18 years of age: A systematic review of observational studies. 2011;377:1011–1018.
2. American Academy of Pediatrics, APLS, 5thed, 2013
3. Dieckmann R, Brownstein D Pediatric Education for Prehospital Professionals, Sudbury, MA: Jones and Bartlett Publishers, American Academy of Pediatrics, 2000:47
4. Dieckmann R et al. Pediatric Emergency Care, Volume 26, #4, April 2010.  Lipincott Williems and Wilkins.