Sleeping bradycardia during recovery from childhood status asthmaticus.

Seventeen of 67 children recovering from status asthmaticus developed sleeping bradycardia. They were compared to a control population of asthmatic children who did not develop sleeping bradycardia and differed only in the low heart rate. The authors speculate that this phenomenon is due to a combination of withdrawal of sympathomimetic stimulation and catch-up in REM (rapid eye movement) sleep.