Related Experiment Videos
The Q-oTc and Q-Tc interval and ionized calcium in newborns
Insights
Ionized calcium (CaF) levels, not ECG QT intervals, are recommended for diagnosing neonatal hypocalcaemia. Measurements showed no correlation between CaF and QT intervals in newborns, infants undergoing exchange transfusion, or those with hypocalcaemia.
Area of Science:
- Neonatal Medicine
- Cardiology
- Clinical Chemistry
Background:
- Neonatal hypocalcaemia is a common clinical issue.
- Electrocardiogram (ECG) parameters like QT intervals are sometimes used to assess calcium levels.
- The reliability of ECG in diagnosing neonatal hypocalcaemia requires further investigation.
Purpose of the Study:
- To investigate the correlation between ionized calcium (CaF) and QT intervals (Q-oTc and Q-Tc) in newborns.
- To evaluate the utility of ECG findings in diagnosing and monitoring neonatal hypocalcaemia.
Main Methods:
- Measurements of ionized calcium (CaF), Q-oTc, and Q-Tc intervals were performed.
- Study groups included healthy newborns, infants undergoing blood exchange transfusion (ET), and infants with clinical hypocalcaemia.
Main Results:
- No significant correlation was found between CaF values and QT intervals.
- QT intervals showed minimal changes despite large fluctuations in CaF during ET.
- Slightly prolonged Q-oTc intervals were observed in hypocalcaemic and ET groups compared to controls.
Conclusions:
- ECG findings, including QT intervals, lack practical implications for diagnosing and managing neonatal hypocalcaemia.
- Measurement of ionized calcium (CaF) is recommended as a reliable guideline for neonatal hypocalcaemia.
Abstract:
Ionized calcium (CaF), Q-oTc and Q-Tc intervals were determined in 31 full-term healthy newborns, 12 infants subjected to blood exchange transfusion (ET) and 10 infants with verified clinical hypocalcaemia. There was no significant correlation between CaF values and QT intervals. The large fluctuations in CaF during ET did not correspond to any similar change in Q-oTc or Q-Tc intervals. The Q-oTc interval was slightly longer in the hypocalcaemic and the blood exchanged groups compared to controls. The Q-Tc interval was somewhat longer in the ET group. The differences in mean values for QT intervals were fairly small and the ranges wide. ECG findings lack practical implications in diagnosing and following neonatal hypocalcaemia and we therefore recommend the measurement of CaF as a guideline.