Nightmares

Nightmares (REM Parasomnias)

Nightmares are classified as parasomnias, which are episodic nocturnal behaviors that often involve cognitive disorientation along with autonomic and skeletal muscle disturbances.
Specifically, nightmares fall under the category of rapid eye movement (REM) parasomnias.
Because they are tied to REM sleep, nightmares are characteristically concentrated in the second half or the last third of the night, when the REM stage of sleep is most prominent.
They are much more common in the pediatric population than partial arousal (non-REM) parasomnias.
Nightmares can be a common presenting behavioral or psychiatric concern during the preschool years.
Furthermore, they can occur as a primary symptom of underlying distress, such as in children experiencing complicated bereavement or Post Traumatic Stress Disorder (PTSD).

The clinical presentation of a nightmare involves frightening or unpleasant dreams that result in a full awakening of the child.
The duration of a nightmare episode typically ranges from 3 to 20 minutes.
Upon waking, the child typically seeks and is comforted by parental reassurance.
Unlike non-REM parasomnias, children who awaken from a nightmare typically have vivid recall and memory of the dream or the event.
The clinical differentiation between nightmares and non-REM sleep terrors is crucial for accurate diagnosis and management.

Feature	Nightmares (REM Parasomnia)	Sleep Terrors (Non-REM Parasomnia)
Timing in Sleep Cycle	Last third of the night (REM sleep).	First third of the night (Slow-wave/deep sleep).
Presentation	Frightening dreams leading to full awakening.	Sudden onset with a spine-chilling scream, intense fear, and thrashing.
Autonomic Activation	Mild (+).	Severe (++++), including tachycardia, diaphoresis, and dilated pupils.
Memory of Event	Vivid recall of the dream upon waking.	Complete amnesia for the event.
Postevent Confusion	Absent (-).	Present (+).
Response to Comfort	Child seeks and is comforted by parental reassurance.	Child is inconsolable, avoids comfort, or exhibits increased agitation with parental comforting.

In most normally developing children, nightmares are benign and self-limiting.
The cornerstone of management relies on parental reassurance.
It is critical to identify and manage any underlying psychosocial stress that may be precipitating the nightmares.
In rare or severe instances, pharmacotherapy involving benzodiazepines may occasionally be used.