Is severe hypercalcemia immediately life-threatening?
OBJECTIVE
Severe hypercalcemia is often considered an emergency because of a potential risk of cardiac arrest or coma. However, there is little evidence to support this. The aim of our study was to assess whether severe hypercalcemia (Ca>4 mmol/l or 16 mg/dl) was associated with immediately life-threatening cardiac arrhythmias or neurological complications in patients admitted to the Emergency Department (ED).


METHODS
A retrospective observational study was carried out over a 5-year period (2008-2012). Eligible patients were admitted to the Adult Emergency Department of Nantes University Hospital and had a calcium concentration in excess of 4 mmol/l. There were no exclusion criteria. The primary outcome was the number of life-threatening cardiac arrhythmias and/or neurological complications during the stay in the ED. The secondary outcomes were correlation between calcium concentrations/ECG QTc intervals and mortality.


RESULTS
A total of 126 204 adult patients had calcium concentrations measured. Thirty one (0.025%) patients had severe hypercalcemia as defined in our study. The median calcium concentration was 4.3 mmol/l (Q1, 4.2; Q3, 4.7) and the median albumin-adjusted calcium concentration was 4.3 mmol/l (Q1, 4.1; Q3, 4.7). No patient presented with a life-threatening cardiac event during stay in the ED. The median ED stay was 7 h 32 min. One patient presented with a coma of multifactorial origin. There was no correlation between calcemia and QTc intervals (P=0.60). Mortality at 1 year was 55% (17 patients).


CONCLUSIONS
We found no cases of immediately life-threatening cardiac arrhythmias or neurological complications associated with hypercalcemia above 4 mmol/l over a 5-year period in a large tertiary ED.
Departments of Emergency Medicine.
Camille
C
Guimard
Departments of Emergency Medicine.
Eric
E
Batard
Nephrology, Nantes University Hospital, Nantes Cedex 01, France.
Frédéric
F
Lavainne
Departments of Emergency Medicine.
David
D
Trewick
D001145:Arrhythmias, Cardiac / Q000175:diagnosis* / Q000209:etiology / Q000401:mortality*; D002118:Calcium / Q000097:blood*; D004636:Emergency Service, Hospital; D005260:Female; D005602:France; D006801:Humans; D006934:Hypercalcemia / Q000097:blood / Q000150:complications* / Q000175:diagnosis; D008297:Male; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index
D002118:Calcium