PurposeIt is to examine clinical manifestations, early biochemical indicators, and risk factors for non-oliguric hyperkalemia (NOHK) in extremely low birth weight infants (ELBWI).Materials and MethodsWe collected clinical and biochemical data from 75 ELBWI admitted to Ajou University Hospital between Jan. 2008 and Jun. 2011 by reviewing medical records retrospectively. NOHK was defined as serum potassium ≥7 mmol/L during the first 72 hours of life with urine output ≥1 mL/kg/h.ResultsNOHK developed in 26.7% (20/75) of ELBWI. Among NOHK developed in ELBWI, 85% (17/20) developed within postnatal (PN) 48 hours, 5% (1/20) experienced cardiac arrhythmia and 20% (4/20) of NOHK infants expired within PN 72 hours. There were statistically significant differences in gestational age, use of antenatal steroid, and serum phosphorous level at PN 24 hours, and serum sodium, calcium, and urea levels at PN 72 hours between NOHK and non-NOHK groups (p-value <0.050). However, there were no statistical differences in the rate of intraventricular hemorrhage, arrhythmia, mortality occurred, methods of fluid therapy, supplementation of amino acid and calcium, frequencies of umbilical artery catheterization and urine output between the two groups.ConclusionNOHK is not a rare complication in ELBWI. It occurs more frequently in ELBWI with younger gestational age and who didn't use antenatal steroid. Furthermore, electrolyte imbalance such as hypernatremia, hypocalcemia and hyperphosphatemia occurred more often in NOHK group within PN 72 hours. Therefore, more use of antenatal steroid and careful control by monitoring electrolyte imbalance should be considered in order to prevent NOHK in ELBWI.

Purpose: To compare the effect of humidified high flow nasal cannula (HHFNC) with that of nasal continuous positive airway pressure (NCPAP) as the mode of extubation in very low birth weight infants (VLBWI). Methods: Medical records were retrospectively reviewed for 219 VLBWI who were admitted to the neonatal intensive care unit of Ajou University Hospital from January 2009 through December 2012; 87 were supported by noninvasive ventilation (NIV) after extubation (HHFNC n=47, NCPAP n=40). Extubation failure was defined as the need for reintubation within 1 week of extubation. Results:(1) There were no significant differences between the groups in demographic data such as gestational age, birth weight, and age at extubation. (2) There were no significant differences in fraction of inspired oxygen (FiO 2 ) (HHFNC 0.23±0.03 vs. NCPAP 0.23±0.03, P-value .937) and peak inspiratory pressure (HHFNC 11±6.6 cmH 2 O vs. NCPAP 10.3±3.4 cmH 2 O, P-value .559) before extubation. (3) The rate of extubation failure and FiO 2 values after extubation were similar in the 2 groups (extubation failure, HHFNC 5/47 vs. NCPAP 5/40, P-value 1.000; FiO 2 , HHFNC 0.24±0.05 vs. NCPAP 0.25±0.04, P-value .399). (4) Among patients who received NIV after extubation once but did not receive further intubation, the duration of NIV or duration of oxygen supply were not significantly different between the groups (NIV, HHFNC 12.4±9.1 days vs. NCPAP 8.7±12.3 days, P-value .159, oxygen supply, HHFNC 49.0±40.3 days vs. NCPAP 50.9±41.3 days, P-value .844) or bronchopulmonary dysplasia rate (HHFNC 24.3% vs. NCPAP 34.4%,. Conclusion: HHFNC is as effective as NCPAP for weaning VLBWIs from invasive mechanical ventilation.