Chronic Hypercalcaemia Secondary to Hyperpara-Thyroidism: A Risk Factor During Anaesthesia?

Abstract

Hypercalcaemia (increased plasma total calcium concentration, [Ca]) has been associated with serious ventricular arrhythmia and sudden cardiac arrest in patients with hyperparathyroidism. To support our impression that the occurrence of such complications during surgery is rare, we examined the records and e.c.g. of 193 patients with moderate hypercalcaemia ([Ca] = 2.89 +/- 0.02 mmol litre-1, mean +/- SEM) secondary to histologically demonstrable parathyroid hyperfunction, who were admitted to hospital between 1974 and 1978 We found that ventricular arrhythmia was not recorded for any patient, and A-V junctional rhythm was present at the beginning of operation in two. Before operation a statistically significant although minimal shortening of corrected values of Q-T interval occurred compared with a control group (n = 60). However, duration of the corrected Q-T interval was not diagnostic of increased [Ca] in a given patient with hyperparathyroidism.

Cardiac conduction in patients with hypercalcaemia due to primary hyperparathyroidism

“…Such disturbances could very well explain either partially or wholly the occurrence of cardiac arrhythmias. Gunst and Drop (1980) reported findings similar to ours in 193 patients undergoing surgery for hyperparathyroidism. Although these patients were studied only with a 12-lead electrocardiogram before surgery and electrocardiographic monitoring during surgery, no significant differences with respect to cardiac conduction disturbances were observed as compared to a control group of patients undergoing surgery for other reasons.…”

Digoxin, hypercalcaemia, and cardiac conduction

“…No ventricular arrhythmias were noted in this series 12. Continuous 24-hour ECG monitoring undertaken in eight patients with hypercalcaemia (2.9–4.4 mmol/l) due to metastatic breast cancer did not detect any significant arrhythmias.…”

Is the cortical capillary renamed as the transcortical vessel in diaphyseal vascularity?

“…He explained “Apparuit igitur, ubi, quasque per vias, quae per ossa pene‐trare vasa dixi, intrent exeantve: quorum quae ab exteriore parte sunt, ea rami vasorum sunt periostei: quae ab interiore, ad medullam visa sunt pertinere (It, therefore, appeared as I have said previously, that whatever the routes by which blood vessels penetrate the bones, whether going in or coming out, those from the outer part of the bone are branches of the periosteal vessels; those which come from the inner aspect of the cortex belong to the medullary system).” His findings of bone vascularity, that the long bone has combined periosteal and medullary circulation, remained accepted for 150 years. This finding was challenged by Bridgeman and Brookes (1996), Brookes and Harrison (1957), Dillaman (1984), Dillaman, Roer, and Gay (1991), Gunst and Drop (1980), Montgomery, Sutker, Bronk, Smith, and Kelly (1988) and Rhinelander, Phillips, Steel, and Beer (1968). The tiny channels arranged in longitudinal orientation were called Haversian canal, and short horizontal limb were termed as Volkmann's canal (Vasciaveo & Bartoli, 1961).…”