Does the delay in the start of replacement therapy influence recovery from postoperative hypocalcemia?

To the Editor:

We have read with interest the article published in your journal by Gutiérrez Fernández et al.¹ regarding biochemical parameters and the appearance of post-thyroidectomy hypocalcemia. In their study, hypocalcemia was defined as the appearance of symptoms of hypocalcemia or persistence of total serum calcium <8 mg/dL 48 h after the intervention. This paper has certain similarities with a communication our group presented at the 33rd National Surgery Congress, in which we analyzed the static and dynamic definitions of hypocalcemia considering the presence of symptoms². However, one important difference is the time when symptoms were evaluated. In our case, symptoms were evaluated 24 h after surgery, at which time we initiated treatment for biochemical hypocalcemia, even when asymptomatic. In the study by Gutiérrez Fernández et al., however, most patients were not treated until after 48 h, as long as they remained asymptomatic.

This management protocol differs from the current recommendations of leading clinical guidelines^3,4 and the most recent reviews regarding hypocalcemia⁵. These documents recommend early treatment of biochemical hypocalcemia without waiting for symptoms to appear, even in the first few hours right after surgery. It should be noted that the period of the Gutiérrez Fernández et al. study predates these recommendations.

However, precisely because of this difference, we believe it would be very interesting to know some additional data from the study, which would allow us to better define the advantages of early initiation of treatment for asymptomatic biochemical hypocalcemia. Specifically, we believe that it would be interesting to know the rate of the appearance of symptoms after the 24-h lab workup, which hypothetically could have been avoided or at least attenuated with early treatment.

Another factor that is not clearly defined is the long-term evolution of biochemical hypoparathyroidism depending on whether replacement treatment is started early or not. In this context, the data obtained by studies like the Gutiérrez Fernández et al. article have even greater value, since a prospective design analyzing this evolution would be very controversial from an ethical standpoint today. This analysis could be especially interesting if it could demonstrate the possible advantage (or lack thereof) of early treatment of asymptomatic hypocalcemia in terms of long-term recovery.

Funding

This article has received no funding of any kind.

Conflict of interests

The authors have no conflict of interests to declare.