Szemészet, 1975 (112. évfolyam, 1-3. szám)

1975 / 3. szám

Szemészet 112. 165—174. 1975.

Eye Clinic of the University of Rome (Director: Prof. Cr. B. Bietti)

Glycerol-Sodium Ascorbate, a Safe, Stable, Intravenous Osmotic Solution to Reduce Intraocular Pressure*

G. В. В I E XT I, M. D., M. V I R N О**, M. D., J. PECOKI-8IEA1D I*», Ph. D. and

E. D. MOTOLESE.M. D.

The cerebral dehydration action of oral and intravenous glycerol as an osmotic agent was first described by one of us (Virnoet al., 1961) in the experimentally induced cerebral edema in rabbits. In a later study, oral and intravenous glycerol was shown to reduce intraocular hypertension provoked in rabbits by means of, respectively, water loading in the peritoneal cavity (Virno et al., 1962) and introduction in the anterior chamber of 2.5% methylcellulose (Virno et al., 1965).

Since 1962, glycerol attained a widespread application orally as an ocular hypotonizing agent in the preoperatory treatment and in the therapy of acute glaucoma attacks (Virno et al., 1963) and as an intracranial hypotensive agent (Cantore et al., 1964; Tourtellotte et al., 1972).

Subsequently, as in certain conditions (general anesthesia and predisposition to vomiting) the oral use of the drug may not be advisable, we studied the possibility of its intravenous administration. It was shown that the intravenous infusion of glycerol in physiological saline, at the doses able to reduce the intraocular pressure (0.5—1.5 g/Kg body weight) produced hematuria both in man (Bővet et al., 1961) and in the experimental animal (Della Восса et al., 1966). Actually, after the introduction of 2 g/Kg body weight of a 30% glycerol solution in physiological saline in the rabbit, there was a block of diuresis lasting 30 to 40 minutes. Throughout this period, there was a vasoconstriction of the afferent glomerular arterioles, evidenced by numerous areas of subcapsular ischemia. A reflex vasodilation followed. The glomerular loops were found to be swollen and occupied the entire inner capsular space. Intracapsular and interstitial hemorrhages were also noted. The vasodilation lasted five to eight hours, allowing the passage of blood by rexis and diapedesis from the glomerular filter. Twelve hours later, the renal alterations had disappeared and the morphologic pattern of the kidney was found to be completely normal. In a subsequent work (Virno et al., 1966), we reported that the only substance among those tested capable of completely eliminating the occurrence of anuria, hematuria and hemoglobinuria and of the renal histological alterations produced in the rabbit by the intravenous administration of 30% glycerol in saline was the sodium salt of Vitamin C—sodium ascorbate. This drug was proven to protect completely against the untoward effects produced on the kidney by intravenous glycerol through an immediate diuresis. In fact, with the intravenous administration of 2 g/Kg body weight of 30% glycerol in 20% sodium ascorbate no anuria nor hematuria were ever noted and no morphologic alterations were noted in the kidneys of rabbits.

Highly favourable results were obtained by us both in the ophthalmological (Virno et al., 1965, 1966) and neurosurgical (Cantore et al., 1966) fields with doses of 0.5 to 1 g/Kg body weight of 30% glycerol in 20% sodium ascorbate. No hematuria or hemoglobinuria were ever observed.

* Dedicated to Professor M. Radnót on the 25th anniversary of her Professorship.

** From the Laboratory of Ocular Physio-Pharmacology of the Eye Clinic of the University of Rome.

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