Hypocalcemia is common in the first 48 h of life in ELBW infants

BACKGROUND: The incidence of early hypocalcemia in extremely low birthweight (ELBW) infants is unknown because the distribution of serum calcium values in this population is not defined. OBJECTIVE: To determine the range of serum calcium values in ELBW infants during the first 48 h of life and the risks associated with low values. DESIGN/METHODS: Retrospective analysis of all ELBW infants admitted on day 1 of life from April 2004 to October 2006. Demographic variables, therapy, serum calcium (Ca), pH, albumin, and blood ionized Ca were recorded. RESULTS: There were 381 Ca levels obtained from 111 patients. Mean Ca was 6.90 mg/dL (1.73 mmol/L) (5(th)-95(th) percentile: 5.16-8.80). Ca levels rose after 24 h of life. Almost one quarter (23.1%) of the Ca levels were low by current standards. The majority of subjects (59.9%) had at least one hypocalcemic value. CONCLUSIONS: Serum Ca values are lower in ELBW infants and inconsequential. Thus, hypocalcemia should be re-defined for ELBW infants.