Asleep, or Not

Sapna Kudchadkar

In the PICU, pediatric intensivist Sapna Kudchadkar.

The last thing one expects a patient to get in the cacophony of the Pediatric Intensive Care Unit (PICU) is deep, restorative sleep, but such sleep may be vital for short- and long-term health. So says Sapna Kudchadkar, a pediatric intensivist who specializes in sleep disturbances among critically ill children. While sleep issues in hospital settings have been fairly well studied in adults, the same is not true of children. That leaves Kudchadkar in the role of detective, uncovering clues as to what disrupts sleep in the PICU, and the physiological consequences.

Consider first the children themselves. “They’re scared, they’re anxious, they don’t understand what’s going on; that can lead to sleep disruption at baseline,” says Kudchadkar.

Then there’s the PICU environment. “The noise is constant, there’s talking at the bedside, the lights are on 24-7,” she notes. “There’s a balance between turning down the lights so a child can get sleep and get their circadian rhythms in order, but there’s worry that if we turn off the lights we might miss a very subtle change in a child’s clinical status. So you’re navigating all those factors.”

Drugs and mechanical assist devices play a role as well. Sedatives and analgesics, common PICU tools that at higher doses can inhibit restorative sleep, are of particular interest to Kudchadkar. “We use the terms ‘sedation’ and ‘sleep’ interchangeably,” she says. “Just because a child’s eyes are closed we assume they’re sleeping. I wondered ‘do we know that they’re actually sleeping?’”

Similarly, ventilators set at a constant rate are at odds with how breathing naturally changes as one moves into deeper levels of sleep, a dysynchrony that may lead to severe sleep disruption.”

The fallout from such sleep disruption can be disastrous. In the PICU, it can lead to delirium and an impending insult such as acute sepsis. Just as disturbing is the notion that sleep loss in the PICU could cause serious issue long after hospitalization. “Every single child that comes through our PICU, their brains are actively developing; if they were healthy, natural sleep is playing a major role in brain plasticity,” says Kudchadkar. “But then you come to the PICU and a child is sleep deprived. What happens down the line? Behavior problems? Anxiety?”

Kudchadkar has begun enrollment of patients in a study that will begin to answer those questions by monitoring their sleep/wake cycles as they move from the hospital back to the home setting. Small wrist-watch sized devices called actigraphs will non-invasively measure activity indicating whether or not a patient is asleep.

Eventually a better understanding of encouraging quality sleep in the PICU could yield wholesale changes of how patients are managed during critical illnesses. Kudchadkar says that new initiatives that get patients up and moving—even when they’re attached to breathing tubes—improve sleep/wake cycles. Call them the circle of healing.
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