Low incidence of acute kidney injury in VLBW infants with restrictive use of mechanical ventilation

Abstract

Background: We assessed the incidence of and risk factors for acute kidney injury (AKI) in very low birthweight infants (VLBW) in a center with a specific neonatal management protocol focusing on avoidance of early mechanical ventilation (MV).

Methods: This retrospective single center analysis includes 128 infants born in 2020 with a gestational age ≥ 22 weeks who were screened for AKI using the nKDIGO criteria.

Results: AKI was identified in 25/128 patients (19.5%) with eight of them (6.3%) presenting with severe AKI. Low gestational age, birthweight and 10-minute Apgar score as well as high CRIB-1 score were all associated with incidence of AKI. Forty-five percent of the infants with MV developed AKI vs. 8.9% of those without MV (p < 0.001). Early onset of MV and administration of more than 3 dosages of NSAIDs for patent duct were identified as independent risk factors for AKI in a logistic regression analysis.

Conclusions: We report a substantially lower frequency of AKI in VLBW infants as compared to previous studies, along with a very low rate of MV. A neonatal protocol focusing on avoidance of MV within the first days of life may be a key factor to decrease the risk of AKI in immature infants.

Keywords: AKI; Less-invasive surfactant administration; NSAID; Nephrotoxic medication; Preterm infant.

A higher resolution version of the Graphical abstract is available as Supplementary information

Fig. 1

Flow chart of patient selection process

Fig. 2

Characteristics of AKI episodes. a AKI was diagnosed in 25/128 infants. AKI was characterized as “early AKI” in 12 of the 25 cases (48%). Most cases (68%) were classified as stage 1. Severe AKI was identified in 8 cases (32% of all AKI episodes). In 16 of the 25 infants (64%), the AKI diagnosis was made based on urinary output (UOP) criteria. b ELBW infants experienced AKI more frequently (28%) than infants with a birth weight of > 1000 g (10%, p = 0.011). In the infants with a birth weight < 750 g, AKI was identified in 40% vs. 9% of those with a birth weight of 750–1499 g (p < 0.001). c The proportion of infants suffering from AKI increases with decreasing gestational age at birth. d Infants with an onset of invasive mechanical ventilation (MV) within the first three days of life experienced AKI more frequently (see Tables 3 and 4). e Infants with AKI were more frequently invasively mechanically ventilated than infants without AKI (see Table 3)