BEHAVIOR AND PHYSIOLOGICAL-RESPONSES DURING PRONE AND SUPINE SLEEP INEARLY INFANCY

Aims-To study the effect of prone and supine sleep on infant behaviour , peripheral skin temperature, and cardiorespiratory parameters to aid understanding of why prone sleeping is associated with an increased r isk of sudden infant death syndrome. Methods-Of 33 enrolled infants, 3 2 were studied at 2.5 and 28 at 5 months of age. A computer aided mult ichannel system was used for polysomnographic recordings. Behaviour wa s charted separately. Results-Prone REM (active) sleep was associated with lower frequencies of short arousals, body movements and sighs, an d a shorter duration of apnoeas than supine REM sleep at both ages. At 2.5 months there were less frequent episodes of periodic breathing du ring prone sleep in non-REM (quiet) and REM sleep. Heart rate and peri pheral skin temperature were higher in the prone position during both sleep states at both ages. Conclusions-The observation of decreased va riation in behaviour and respiratory pattern, increased heart rate, an d increased peripheral skin temperature during prone compared with sup ine sleep may indicate that young infants are less able to maintain ad equate respiratory and metabolic homoeostasis during prone sleep.