ABSTRACT
During hypoxic respiratory failure and respiratory distress syndrome in neonates, impairment of renal function is a common course in these pathological states. The effects of hypoxia on the neonatal kidney include the impact on renal perfusion and hemodynamics within the local microcirculation, glomerular filtration rate, free water excretion and diluting ability, and renal tubular transport function. Hypoxemic neonates often present with derangements in renal physiology. However, with progressive severity or duration of hypoxia, these processes become less likely to be reversible and the clinical picture progresses to acute tubular necrosis, acute kidney injury and global dysfunction that may be irreversible. Furthermore, hypoxia and hyperoxic resuscitation can have a long-standing impact on nephron development and long-term renal outcomes. In this review, we discuss the consequences of hypoxic respiratory failure including acute kidney injury, tubular dysfunction and injury, renal vascular function and glomerular filtration. Regarding the oxygen metabolism, it is important to measure renal oxygen supply-demand balance, commonly using near-infrared spectroscopy, in the course of hypoxia and reoxygenation-recovery to avoid hyperoxia. The latter has been shown to be detrimental resulting in renotubular injury and dysfunction. Therefore, international guidelines have been changed to the use of room air in the neonatal resuscitation to avoid hyperoxia since 2010. Among other novel therapeutic approaches, prophylactic administration of aminophylline (an adenosine inhibitor) in asphyxiated neonates has been shown to reduce the incidence of acute kidney injury. Lastly, this review also discusses the protective effects of other experimental pharmacological agents including anti-oxidative agents (N-acetylcysteine), matrix metalloproteinase inhibitor (doxycycline), and nitric oxide donor (l-arginine).
