[Malignant hyperthermia during cataract extraction in an elderly patient]. / Hipertermia maligna durante la extracción de catarata en un anciano.

The case of a 67-year-old patient who suffered an episode of malignant hyperthermia during the extraction of a cataract is described. The outcome was favourable in spite of the lack of sodium dantrolene. Twenty months later the patient was operated on the contralateral eye with local anesthesia presenting no complications. It is worthy of note that the rareness of the syndrome in this age group and in this type of surgery, as well as the probable safeness of local anesthetics in susceptible patients. We also comment on the lack of sodium dantrolene and the nonexistence of a center facilitating information and diagnosis of malignant hyperthermia in our country.

Effect of calcium pidolate on biochemical and hormonal parameters in involutional osteoporosis.

The purpose of this study was to determine the value of calcium pidolate in the treatment of involutional osteoporosis. This compound has been reported to be better absorbed than other calcium salts, to lower the levels of parathyroid hormone (PTH) and to raise those of growth hormone (GH). We accordingly treated one group of 10 women suffering from involutional osteoporosis with the equivalent of 1 g elemental calcium and administered a placebo to a second group of 10 osteoporotic women whose mean age and body surface area were comparable. Basal sequential multiple analysis (SMA-12) was performed in all subjects to determine calcium, phosphorus, alkaline phosphatase (ALP) and total protein levels, the same blood samples being used for the evaluation of mean PTH, GH and osteocalcin (BGP). Urinary 24-h calcium excretion was determined and the calcium/creatinine (Ca/Cr) and hydroxyproline/Cr (HP/Cr) ratios were measured in 12-h fasting urine samples, the results being corrected for glomerular filtrate. The same parameters were measured again following a month of uninterrupted treatment. After 30 days, we observed no differences in either group as regards calcaemia, phosphataemia, ALP, total proteins, PTH, GH, BGP or 24-hour calciuria. The only noteworthy changes seen were significant decreases (P less than 0.001) in the Ca/Cr and HP/Cr ratios in the group treated with calcium pidolate. These results show that calcium pidolate at the dose administered inhibits bone resorption but does not affect the levels of PTH, GH, BGP or ALP in the medium term. Our findings indicate that it has no influence on bone formation.

Osteocalcin, parathormone and hypercalciuria.

Osteocalcin synthesis is dependent on the influence of the renal vitamin D metabolite, 1,25(OH)2D3. This metabolite is an etiological factor in some hypercalciurias, and osteocalcin may thus be a parameter for discovering them. In turn, parathormone, which stimulates 1,25(OH)2D3 synthesis, is also implicated in the hypercalciurias. Mean molecular parathormone, osteocalcin, 24-hour calciuria and the calcium/creatinine and hydroxyproline/creatinine ratios were determined in urine samples obtained after a 12-hour fast from 18 patients with absorptive hypercalciuria and 11 patients with renal hypercalciuria out of a total of 62 patients with renal lithiasis. No changes were observed in osteocalcin or parathormone, indicating that neither is valid for the diagnosis of hypercalciuria. Significant differences were only found in the Ca/Cr ratio (p less than 0.001), which was higher (0.31 +/- 0.07 vs. 0.13 +/- 0.04 mg/mg) in renal hypercalciuria than in absorptive hypercalciuria. No changes in osteocalcin have been reported in the hypercalciurias, but variations in parathormone have been reported, therefore requiring further study and thought to understand the processes involved.