PP-41. Pain and oxidative stress in the newborn

Aim Stressful events are well recognized factors damaging neonatal brain through a complex of events including free radical (FR) generation. We examined whether pain provoked by a routine heel prick can generate an increase in potentially harmful FR in neonatal blood. Materials and methods Advanced oxidation protein products (AOPP) and total hydroperoxide (TH) concentrations were measured at the beginning (sample A) and at the end (sample B) of each sampling in 64 babies (corrected age: 37.2 ± 2.7 weeks) who underwent heel prick for routine blood tests. We scored pain of every procedure in all newborns (ABC pain scale). Results No differences were detected between AOPP and TH blood concentrations at the beginning and at the end of heel prick sampling, considering the whole cohort of babies. Conversely, a significant increase was observed between AOPP and TH blood concentrations considering only those babies who showed the highest pain intensity. When babies' pain was high (ABC score ≥ 4), mean AOPP and TH blood levels increased significantly (AOPP values from 53.5 μm/l ± 41.6 to 63.2 μm/l ± 44.3; p = 0.02; TH values from 218.3 U Carr ± 89.2 to 228.7 U Carr ± 93.3; p = 0.03). A significant correlation was also found between AOPP blood levels ratio (sample B/sample A) in each baby, and the correspondent level of pain (r = 0.308, p = 0.015). Conclusions Even common routine procedures can be potentially harmful for the newborn if they provoke a high level of pain. This study adds new evidence to support the use of effective analgesic procedures for every type of potentially painful event, in order to avoid the dangerous effects of oxidative stress related to FR generation.