Preliminary study of an early identification of postoperative hypocalcaemia after total thyroidectomy

Abstract

Objective: Hypocalcaemia due to parathyroid insufficiency is a disabling complication after thyroidectomy.  It could present with symptoms up to 3 days after surgery, hence patients are hospitalized till then. If symptomatic hypocalcaemia could be predicted, calcium supplements can be given and the patient could be discharged earlier, reducing the hospital stay and costs.

The objective of this prospective observational study was to determine whether symptomatic hypocalcaemia could be predicted with serial measurements of serum ionized calcium levels after thyroidectomy.

Method:Thirty one consecutive patients undergoing either total or completion thyroidectomy were selected.  Serum ionized calcium levels were measured preoperatively, and 6, 18 and 48 hours after surgery, and plotted in a graph.  Symptoms and signs of hypocalcaemia were assessed at the same time intervals.

Results:Tweleve patients (38.7%) had a down ward slope of ionized calcium levels, going below the reference range at 48 hours.  Of these two patients were not symptomatic, and did not require calcium supplements.

All patients who had either a plateau or upsloping of the calcium levels did not develop symptoms or signs of hypocalcemia.

Conclusion:These results of this ongoing study indicate that  downsloping postoperative calcium levels based on the three early calcium measurements is highly predictive of eventual symptomatic hypocalcaemia.  Those patients with either a plateau or upsloping levels could be safely discharged home after 48 hours without calcium supplements.