Effects of Apneic Events on Skin Microcirculation in Preterm Newborns: Applications of Laser-Doppler-Flowmetry

Apnea is one of the most common neonatal respiratory disorders and consist in pauses in respiratory movements lasting more than 20 seconds. The objective of this study was to determine the characteristics of skin blood flow microcirculation in preterm newborn with frequent apneic events with Laser-Doppler-Flowmetry. We have studied 20 preterm newborns with a mean weight of 1560 g (range 1140 – 2150) and a mean post-conceptional age of 31,2 weeks (range 28 – 33). The laser Doppler skin blood flow was measured during 88 apneic events. The newborns were divided into two different groups: GROUP 1 concerning apneic spells in the first 5 days of life; GROUP 2 concerning apneic events in the same newborns from 6 to 10 days of life. We included in our study only 13 of 20 newborns, in which there were apneic events during both periods. A statistically significant difference (p<0.01) was found considering the percentage reduction of skin blood flow perfusion (SBFP). A remarkable increase of mean SBFP reduction was noted in every newborn older than five days. LDF can assume an important role during apneic events suggesting that the newborn is more capable of contrasting the negative effects of apneic spells, centralizing the circle in favour of vital organs.