Oxidative Stress as a Physiological Pain Response in Full-Term Newborns.

This research paper aims to investigate if oxidative stress biomarkers increase after a painful procedure in term newborns and if nonpharmacological approaches, or sex, influence pain degree, and the subsequent OS. 83 healthy term newborns were enrolled to receive 10% oral glucose or sensorial saturation (SS) for analgesia during heel prick (HP). The ABC scale was used to score the pain. Advanced oxidation protein products (AOPP) and total hydroperoxides (TH) as biomarkers of OS were measured at the beginning (early-sample) and at the end (late-sample) of HP. The early-sample/late-sample ratio for AOPP and TH was used to evaluate the increase in OS biomarkers after HP. Higher levels of both AOPP and TH ratio were observed in high degree pain (4-6) compared with low degree pain score (0-3) (AOPP: p = 0.049; TH: p = 0.001). Newborns receiving SS showed a significantly lower pain score (p = 0.000) and AOPP ratio levels (p = 0.021) than those without. Males showed higher TH levels at the end of HP (p = 0.005) compared to females. The current study demonstrates that a relationship between pain degree and OS exists in healthy full-term newborns. The amount of OS is gender related, being higher in males. SS reduces pain score together with pain-related OS in the newborns.

Even routine painful procedures can be harmful for the newborn.

Stressful events can damage neonatal brain through a complexity 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. To this aim, 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. 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 >or=4), mean AOPP and TH blood levels increased significantly; in this case, mean AOPP values increased from 53.5microm/l (SD=41.6) to 63.2microm/l (SD=44.3) and TH values from 218.3UCarr (SD=89.2) to 228.7UCarr (SD=93.3), with a significant p value of 0.02 and 0.036, respectively. A significant correlation was also found between AOPP blood levels ratio (sample B/sample A) in each baby, and the correspondent level of pain. These data show that even common routine procedures can be potentially harmful for the newborn if they provoke a high level of pain.