Admission ionised hypercalcaemia was independently associated with poor functional outcome and mortality in paediatric major trauma, while ionised hypocalcaemia was not independently associated with adverse outcomes after adjustment, highlighting 'the potential value of admission iHyperCa as a marker of physiological stress in injured children.'
Key Findings
Results
Calcium disturbances on admission were prevalent in paediatric major trauma patients, with nearly one-fifth having ionised hypocalcaemia and approximately one-seventh having ionised hypercalcaemia.
Study included 517 children aged <16 years with major trauma (Injury Severity Score ≥15) across 13 UK sites from 2016–2023.
102/517 (19.7%) had ionised hypocalcaemia (iCa <1.16 mmol/L) on admission.
72/517 (13.9%) had ionised hypercalcaemia (iCa ≥1.30 mmol/L) on admission.
Ionised hypercalcaemia on admission was independently associated with poor functional outcome at 30 days after multivariable adjustment.
Poor functional outcome was defined as Glasgow Outcome Scale ≤4 at 30 days.
iHyperCa was associated with poor functional outcome with an adjusted OR of 2.52 (95% CI 1.45 to 4.35).
Analysis was adjusted for injury severity, age categories, mechanism, and sex.
iHypoCa was not independently associated with poor functional outcome after adjustment.
Results
Ionised hypercalcaemia on admission was independently associated with 24-hour mortality with a markedly elevated odds ratio.
iHyperCa was associated with 24-hour mortality with an adjusted OR of 19.33 (95% CI 6.95 to 53.69).
This association persisted after multivariable logistic regression adjusting for injury severity, age categories, mechanism, and sex.
iHypoCa was not independently associated with 24-hour mortality after adjustment.
Results
Ionised hypercalcaemia on admission was independently associated with 30-day mortality.
iHyperCa was associated with 30-day mortality with an adjusted OR of 9.07 (95% CI 4.92 to 16.72).
This association persisted after multivariable adjustment for injury severity, age categories, mechanism, and sex.
iHypoCa was not independently associated with 30-day mortality after adjustment.
Results
Ionised hypocalcaemia was associated with hypotension and coagulation abnormalities on univariable analysis but was not independently associated with treatment requirements, poor functional outcome, or mortality after multivariable adjustment.
The primary outcome was hypotension in the Emergency Department.
Secondary outcomes included treatment requirements within 24 hours, poor functional outcome at 30 days, and 24-hour and 30-day mortality.
iHypoCa associations with hypotension and coagulation abnormalities were identified on univariable but not multivariable analysis.
After adjustment for injury severity, age, mechanism, and sex, iHypoCa was not independently associated with any secondary outcome.
Results
Ionised hypercalcaemia was associated with a high-risk physiological phenotype in injured children.
The authors characterise iHyperCa as being 'associated with a high-risk phenotype.'
The findings highlight 'the potential value of admission iHyperCa as a marker of physiological stress in injured children.'
This is described as a novel finding as no prior paediatric studies had explored the effect of iHyperCa in trauma.
Conclusions
The findings support caution regarding empiric calcium administration in injured children and contextual interpretation of calcium levels.
The authors state findings 'support contextual interpretation of calcium levels' and 'the need for caution with empiric calcium administration in injured children.'
This is relevant given that iHypoCa was not independently associated with adverse outcomes after adjustment, while iHyperCa carried significant risk.
The study was a multicentre retrospective cohort design across 13 UK sites, limiting causal inference.
What This Means
This research examined blood calcium levels measured on hospital admission in 517 children with serious injuries (major trauma) across 13 UK hospitals between 2016 and 2023. Calcium in the blood exists in different forms, and the 'ionised' form is the biologically active type. The study found that abnormal calcium levels — both too low (hypocalcaemia) and too high (hypercalcaemia) — were common, occurring in about one-fifth and one-seventh of injured children respectively. Strikingly, children who arrived with high ionised calcium levels were far more likely to die within 24 hours (about 19 times the odds) or within 30 days (about 9 times the odds), and were more likely to have poor brain or functional recovery at 30 days, even after accounting for how severely injured they were.
In contrast, children with low calcium levels did show signs of low blood pressure and abnormal clotting in simpler analyses, but once researchers adjusted for injury severity and other factors, low calcium was not independently linked to worse outcomes like death or poor recovery. This suggests that low calcium may reflect injury severity rather than being a direct cause of harm on its own. High calcium, however, appeared to be a strong independent signal of physiological stress and danger — a finding that had not previously been reported in children with trauma.
This research suggests that the relationship between calcium and outcomes in injured children is more complex than previously assumed. The results raise questions about the common practice of giving calcium to injured patients as a routine treatment, as the presence of high calcium — rather than low — appears to be a particularly worrying sign. Clinicians may need to interpret calcium levels carefully in the context of the overall clinical picture, rather than treating low calcium automatically. Further research is needed to understand whether and when calcium treatment is helpful or harmful in injured children.
Hibberd O, Barnard E, Karageorgos S, Roland D, Harris T, Thomas S. (2026). Admission ionised calcium disturbances and adverse outcomes in paediatric major trauma: a UK multicentre retrospective cohort study.. BMJ open. https://doi.org/10.1136/bmjopen-2026-122447