Szemészet, 1975 (112. évfolyam, 1-3. szám)
1975 / 3. szám
the urinary sediment obtained by centrifugation. From the table it is clearly evident that after the intravenous administration of 10% glycerol in saline there was always a more or less pronounced hematuria, whereas with 10% glycerol + 10% sodium ascorbate no hematuria was ever noted. Conclusions The data obtained by us point out clearly that the intravenous administration of 10% glycerol in saline brings about untoward side-effects and therefore should be avoided. Actually, microscopic and, frequently, macroscopic (especially in the aged patient) hematuria was almost always encountered both in the experimental animal and in man. For this reason we cannot agree with Meyer, Mathew, El-shewy, Holtmann and coworkers on the absence of toxic effects following the intravenous infusion of 10% glycerol in saline. On the basis of our preceeding and recent researches, we believe that glycerol can be administered intravenously only if associated with sodium ascorbate. Up to now, however, sodium ascorbate did not find a wide clinical application, as the preparation of the hypertonic solution (10 to 20%) presented several problems of stability and maintenance throughout time. The investigations carried out by us showed that by means of the technique described in detail in the present work a duration of activity and a stability of at least two years could be obtained. In consideration of the recent findings with intravenous glycerol in the treatment of cerebral edema and infarction, we thought it convenient to examine the effects of a 10% glycerol -f-10% sodium ascorbate solution also in the ophthalmological field. The association has proven highly valuable intravenously at the doses of 0.6—1 g/Kg body weight, in reducing intraocular pressure both in the preoperatory treatment and in all those cases where a decrease in ocular hypertension by means of an osmotic mechanism is needed. Our investigations on the behaviour of the serum osmolality, showed that the hypotensive effect is bound to an increase in serum osmotic pressure. The infusion of 10% glycerol +10% sodium ascorbate never induced either local (at the point of injection) or systemic disturbances, even in those cases where the rate was higher than 100 drops per minute. The hypotensive effect proved to be maximal already after 30—40 minutes from the start of the infusion, (at the rate of 100 drops/minute) and was maintained for more than two hours. Such behaviour of the intraocular pressure should be kept in mind in the preoperatory treatment, in order to proceed with the surgical intervention at the moment of the maximum hypotensive effect. In the patients submitted to surgery for cataract, who received 0.8—1 g/Kg body weight of 10% glycerol + 10% sodium ascorbate, we always found a soft eye at moment of intervention. This results from the marked vitreous dehydration induced by the osmotic agent, as previously pointed out by Bucci and Virno (1968) in the experimental animal. No tendency to vitreous issue was ever noted. Finally we would emphasize the behaviour of the blood sugar levels observed after the infusion of 10% glycerol +10% sodium ascorbate. Actually, since a long time, there is a diffuse opinion that glycerol increases glycemic levels and that its administration therefore is contraindicated in diabetic patients. We would like to put into evidence that our patients, both normal and diabetic, never showed significant changes in blood sugar levels, following this concentration. 172
