Near infrared spectroscopy (NIRS) is a non-invasive tool providing real-time continuous measurement of regional cerebral blood oxygenation and indirect blood flow. The aim of this review is to determine the best evidence to guide the use of NIRS to detect and avoid abnormalities of cerebral perfusion and oxygenation in newborns with bradycardia. For this systematic review according to PRISMA Statement, we reviewed papers from 2000 to 2023. Research articles, trial, classical articles, observational studies applying NIRS in term and preterm neonates with bradycardia were selected if the title and/or abstract suggested an association between bradycardia or bradycardia associated with apnoea and modification of cerebral oxygenation. All included studies (Table 1) were conducted on male and female newborns with gestational age (GA) between 22.6 and 42 weeks and birth weight (BW) between 212 and 3460 g. The definition of bradycardia and cerebral desaturation differed among authors. Seven out of nine papers agreed on association between bradycardia and cerebral desaturation, but no author indicated the cut-off of heart rate (HR) under which cerebral desaturations occur. No study focused on long-term outcome related to cerebral desaturation. Even if cut-off values of HR causing cerebral desaturation are not clear and a well-fixed definition of cerebral desaturation has not yet been standardized, the studies demonstrated that bradycardia events lead to reduction of cerebral saturation. Continuous monitoring of HR and cerebral saturation by non-invasive tools could play a key role in the assessment of newborns.

Background/Objectives: Iron deficiency (ID) is the most common nutritional disorder in childhood worldwide. It has profound consequences for growth, neurodevelopment, behaviour, and overall health. Despite the long-standing efficacy of oral ferrous salts, their poor gastrointestinal tolerability and adherence challenges have spurred the development of alternative formulations and innovative dosing strategies. Methods: We conducted a narrative review of national and international guidelines, pediatric randomized controlled trials, observational and cohort studies, cost-effectiveness analyses, diagnostic method papers, and reviews, with emphasis on diagnostic innovations, therapeutic outcomes, tolerability, and formulation-specific efficacy. Results: Ferrous salts remain the gold standard for efficacy, low cost, and guideline endorsement, but up to 40% of children experience GI intolerance. Therefore, a lower dosage of ferrous salts has been proposed for IDA as still being an efficacious and better-tolerated schedule. Also, alternate-day dosing improves absorption and tolerability and is supported by a recent pediatric RCT. Newer formulations—ferric polymaltose, ferrous bisglycinate, co-processed bisglycinate with alginate (Feralgine™), and vesicular encapsulated forms such as sucrosomial and liposomal ferric pyrophosphate—showed improved tolerability and palatability, supporting adherence with hematologic outcomes comparable to ferrous salts, particularly in children with intolerance, malabsorption, or inflammatory comorbidities. Intravenous iron is effective and safe with modern preparations and is reserved for severe anemia, malabsorption, or oral therapy failure. Conclusions: Oral ferrous salts should remain the first-line therapy in pediatric ID/IDA. Future pediatric trials should prioritize head-to-head comparisons of formulations, hepcidin-guided dosing, and patient-centred outcomes, including neurocognitive trajectories and quality of life.