ESPN 50th Annual Meeting

ESPN 2017


 
Continuous renal replacement therapy in neonates with hyperammonemia
HEEYEON CHO 1 HAE IL CHEONG 2 HYE WON PARK 3 JI HONG KIM 4

1- SAMSUNG MEDICAL CENTER, SUNGKYUNKWAN UNIVERSITY SCHOOL OF MEDICINE
2- SEOUL NATIONAL UNIVERSITY
3- SEOUL NATIONAL UNIVERSITY BUNDANG HOSPITAL
4- YONSEI UNIVERSITY COLLEGE OF MEDICINE
 
Introduction:

Continuous renal replacement therapy (CRRT) is one of the useful modalities for the critical care of neonates with hyperammonemia caused by inborn errors of metabolism (IEM) because the medical therapy will not rapidly clear ammonia and hyperammonemia could cause the poor neurologic outcomes. The rapid reduction of ammonia levels through CRRT may decrease neonate mortality and morbidity. However, CRRT in neonates had many limitations such as vascular access, or hypotension. The CRRT effects upon ammonia levels are poor characterized, and the optimal CRRT prescription for neonatal hyperammonemia remains unknown. The aim of this study was to assess the clinical characteristics of neonates with hyperammonemia receiving CRRT and the CRRT effects upon ammonia levels and outcomes.

Material and methods:

We retrospectively reviewed the medical records of neonates with hyperammonemia caused by IEM who were admitted to the neonatal intensive care units of Samsung Medical Center, Seoul, Republic of Korea between January 2008 and December 2016 where they underwent at least 24 h of CRRT.

Results:

A total of 13 neonates (male to female ratio 2.3:1) were included in this study, of whom 3 (23 %) were born prematurely. Birth weight ranged from 1.7 to 3.7 kg. The etiology of IEM included ornithine transcarbamylase deficiency (n=4), citrullinemia (n=4), carbamoyl phosphate synthetase deficiency (n=2), propionic academia (n=2), and long-chain L-3-Hydroxy acyl-CoA dehydrogenase deficiency (n=1). The median age at the time of CRRT initiation and the median duration of CRRT was 5 and 4 days, respectively. The mean blood flow rate was 8 ml/kg/min, and the mean dialysis/replacement flow rate (effluent volume) was 3,400 mL/h/1.73m2, which was higher than flows used in neonates with acute kidney injury. The mean ammonia levels at the CRRT initiation was 1197 ┬Ámol/L and the time required for half reduction in ammonia levels ranged from 6 to 24 (median 12) hours. The mean ammonia levels after 48 hr CRRT was 228 ┬Ámol/L. There is no correlation between effluent volume and the time required for half reduction in ammonia levels. Three patients (23 %) showed the rebound elevation of ammonia levels after termination of CRRT, and CRRT was restarted during the hospitalization periods. The duration of hospitalization ranged from 4 to 86 (median 37) days, and 4 patients died during follow-up.

Conclusions:

Clinically significant ammonia clearance can be achieved within 48 hr in neonates with hyperammonemia utilizing CRRT. Our study suggested that a higher flow CRRT might not guarantee the rapid reduction in ammonia levels.