Chronic hypercalcaemia secondary to hyperparathyroidism: a risk factor during anaesthesia?

Area of Science:

• Endocrinology
• Cardiology
• Surgical Complications

Background:

• Hypercalcaemia, or increased plasma calcium, is linked to serious cardiac events like ventricular arrhythmia and sudden cardiac arrest in hyperparathyroidism patients.
• The frequency of these surgical complications in patients with moderate hypercalcaemia requires further investigation.

Purpose of the Study:

• To assess the incidence of ventricular arrhythmia and other cardiac complications during surgery in patients with moderate hypercalcaemia secondary to hyperparathyroidism.
• To determine if the corrected QT interval can serve as a diagnostic marker for hypercalcaemia in this patient group.

Main Methods:

• Retrospective analysis of medical records and electrocardiograms (ECGs) from 193 patients with moderate hypercalcaemia due to parathyroid hyperfunction (1974-1978).
• Comparison of ECG findings, specifically the corrected QT interval, with a control group of 60 patients.
• Evaluation for recorded ventricular arrhythmia and A-V junctional rhythm at the start of surgery.

Main Results:

• No cases of ventricular arrhythmia were recorded among the 193 patients.
• Two patients exhibited A-V junctional rhythm at the beginning of their operations.
• A statistically significant, though minimal, shortening of the corrected QT interval was observed before surgery compared to the control group.
• The corrected QT interval duration was not found to be diagnostic for increased calcium levels in hyperparathyroidism patients.

Conclusions:

• Serious ventricular arrhythmias and sudden cardiac arrest appear to be rare surgical complications in patients with moderate hypercalcaemia from hyperparathyroidism.
• While a minimal shortening of the corrected QT interval occurs, it is not a reliable diagnostic indicator for hypercalcaemia in patients with hyperparathyroidism.