Acute kidney injury is associated with bronchopulmonary dysplasia/mortality in premature infants

• Published in: Pediatric nephrology (Berlin, West) Vol. 30; no. 9; pp. 1511 - 1518
• Main Authors: Askenazi, David, Patil, Neha R., Ambalavanan, Namasivayam, Balena-Borneman, Jessica, Lozano, David J., Ramani, Manimaran, Collins, Monica, Griffin, Russell L
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-09-2015; Springer; Springer Nature B.V
• Subjects: Acute kidney failure; Acute Kidney Injury - blood; Acute Kidney Injury - complications; Acute Kidney Injury - diagnosis; Acute Kidney Injury - mortality; Acute Kidney Injury - physiopathology; Apgar Score; Birth weight; Bronchopulmonary Dysplasia - diagnosis; Bronchopulmonary Dysplasia - mortality; Bronchopulmonary Dysplasia - physiopathology; Bronchopulmonary Dysplasia - therapy; Care and treatment; Cohort analysis; Cohort Studies; Creatinine; Creatinine - blood; Critically ill persons; Demographic aspects; Electrolytes; Female; Gestational Age; Health aspects; Humans; Hypotheses; Infant, Newborn; Infant, Premature - metabolism; Kidneys; Lung diseases; Male; Medicine; Medicine & Public Health; Mortality; Nephrology; Original Article; Outcome Assessment, Health Care; Oxygen Inhalation Therapy - methods; Oxygen Inhalation Therapy - statistics & numerical data; Patient outcomes; Pediatrics; Physiology; Preeclampsia; Premature babies; Premature birth; Premature infants; Prospective Studies; Renal Elimination; Respiration, Artificial - methods; Respiration, Artificial - statistics & numerical data; Risk Factors; Survival Analysis; United States - epidemiology; Urology; Ventilators; Water-Electrolyte Imbalance - etiology; Water-Electrolyte Imbalance - physiopathology; United States; United States > US; Acute lung injury; Organ crosstalk; Neonate; Acute renal failure; Chronic lung disease
• ISSN: 0931-041X; 1432-198X
• DOI: 10.1007/s00467-015-3087-5

Background
Acute kidney injury (AKI) impairs electrolyte balance, alters fluid homeostasis and decreases toxin excretion. More recent data suggest it also affects the physiology of distant organs.
Methods
We performed a prospective cohort study which invloved 122 premature infants [birth weight (BW) ≤1200 g and/or gestational age (GA) <31 weeks] to determine relationships between AKI and bronchopulmonary dysplasia (BPD)/mortality. Days until oxygen discontinuation was compared between those with and without AKI in survivors who received oxygen for ≥24 h.
Results
Acute kidney disease, defined by a rise in serum creatinine (SCr) of ≥0.3 mg/dl or an increase in SCr of ≥150 %, occurred in 36/122 (30 %) of the premature infants. Those with AKI had a 70 % higher risk of oxygen requirement or of dying at 28 days of life [relative risk (RR) 1.71, 95 % confidence interval (CI) 1.22–2.39;
p
< 0.002]. This association remained after controlling for GA, pre-eclampsia, 5 min Apgar score and percentage maximum weight change (max % weight Δ) in the first 4 days (RR 1.45, 95 % CI 1.07–1.97);
p
< 0.02). Similar findings were noted for receipt of mechanical ventilation/death by day 28 (adjusted RR 1.53, 95 % CI 1.05–2.22;
p
< 0.03). Those without AKI were 2.5-fold more likely to come off oxygen [hazard ratio (HR) 1.3–5;
p
< 0.02) than those with AKI, even when controlling for GA, pre-eclampsia, 5 min Apgar and max % weight Δ (multivariate HR 2.0, 95 % CI 0.9–4.0;
p
< 0.06).
Conclusions
In premature infants, AKI is associated with BPD/mortality. As AKI could lead to altered lung physiology, interventions to ameliorate AKI could improve long-term BPD.