Hypertonic agent

Luxenberg MN, Green K. Reduction of comeal edema with topical hypertonic agents.AmJ Ophthalmol 1971 71 847-853 Mishima S, Hedbys BO. Physiology of the cornea, hit Ophthalmol Clin 1968 8 527-560. 

Treatment options are primarily palliative, with the goal of improving patient comfort and function. The use of topical ophthalmic hypertonic agents may reduce epithelial edema related to Fuchs dystrophy however, these agents do not reduce stromal edema. The use of topical 5% sodium chloride drops six to eight times daily, along with 5% sodium chloride ointment instilled into the conjunctival sac at bedtime, may be instituted to determine... 

If there is a treatable cause, its management is necessary for resolution of the edema. If, however, the corneal edema appears to be due to changes in endothelial function, hyperosmotic therapy with 5% sodium chloride solution four to eight times a day and 5% sodium chloride ointment in the conjunctival sac at bedtime is the most appropriate treatment.Treatment with hypertonic agents... 

Once the epithelial defect is healed, artificial tears should be used four to eight times daily, and hypertonic agents, such as 5% sodium chloride ointment, should be administered at bedtime for 3 to 6 months. Patients should continue using hypertonic agents for several months after... 

Osmotherapy employs agents such as mannitol, glycerol, and hypertonic saline to create an osmotic gradient between the brain (optimally, the edematous infarcted tissue) and the bloodstream, such that water is drawn out from the brain, thereby reducing edema. Each of these agents has been shown to be effective, and may be used alone or in combination with a diuretic, such as furosemide. Their action, however, depends upon an intact blood-brain barrier (BBB), and concerns have been raised for possible paradoxical worsening when one is absent. In this hypothesis, mannitol extravasates from the vessel into the interstitial tissue and water follows a new osmotic... 

Dornase alfa (Pulmozyme ) is a recombinant human (rh) DNase that selectively cleaves extracellular deoxyribonucleic acid (DNA). This DNA is released during neutrophil degradation and contributes to the high viscosity of CF sputum. Nebulization of dornase alfa 2.5 mg once or twice daily improves daily pulmonary symptoms and function, reduces pulmonary exacerbations, and improves quality of life.16 N-acetylcysteine and hypertonic saline are other mucolytic agents that are occasionally used however, they are not preferred agents due to a greater incidence of bronchospasm and unpleasant odor and taste.5... 

Hypertonic hyponatremia is usually associated with significant hyperglycemia. Glucose is an osmotically active agent that leads to an increase in TBW with little change in total body sodium. For every 60 mg/dL (3.33 mmol/L) increase in serum glucose above 200 mg/dL (11.1 mmol/L), the sodium is expected to decrease by approximately 1 mEq/L (1 mmol/L). Appropriate treatment of the hyperglycemia will return the serum sodium to normal.15... 

Most studies were performed with hyperosmolar solutions. Hypertonic disruption is under clinical evaluation for enhanced delivery of small molecular weight cytostatic agents to brain tumours. Technically, the procedure is performed as a high-flow short-term infusion of 25% mannitol or arabinose under general anaesthesia. The underlying mechanism is a sequelae of endothehal cell shrinkage, disruption of tight junctions and vasodilatation by osmotic shift [72]. 

Clonidine raises systemic blood pressure and heart rate by stimulating o -adrenorecep-tors in certain parts of the CNS, and it is used mainly as an antihypertensive agent. Clonidine is used in various forms of hypertonic illnesses and for stopping hypertensive attacks. It is also used in ophthahnological practice for open-angle glaucoma. Synonyms of clonidine are hemiton, catapres, and clofelin. 

The development of low osmolar non-ionic X-ray contrast agents has resulted in a distinct reduction in the toxicity and the observed side-effects in patients. However, as already mentioned the osmotic activity of MRI contrast agents is less important in view of the smaller injection volumes which are used. All the formulations of extracellular gadolinium chelates are hypertonic when compared with blood. But the overall increase in osmolality after injection of even 0.3 mmol/kg body weight is insignificant. Osmololatiy-induced adverse reactions have been observed rarely not only because of the relatively small injection volumes but also because of the rapid dilution of the injected agent in the blood. 

Physical therapists may encounter the use of local anesthetics in several patient situations because of their various clinical applications. For example, therapists may be directly involved in the topical or transdermal administration of local anesthetics. As discussed earlier, repeated topical application of local anesthetics may help produce long-term improvements in motor function in patients with skeletal muscle hypertonicity, so therapists may want to consider incorporating topical anesthetics into the treatment of certain patients with CNS dysfunction. Therapists may also administer local anesthetics transdermally, using the techniques of iontophoresis and phonophoresis. Agents such as lido-caine can be administered through this method for the treatment of acute inflammation in bursitis, tendinitis, and so on. 

In vivo microdialysis is a technique that allows sampling of extracellular levels of neurotransmitters in discrete regions of the brain. The extracellular neurotransmitter levels provide an indication of the net activity of a particular set of neurons, including release, synthesis, and uptake, from conscious unanesthetized animals. For example, in vivo microdialysis studies have shown that extracellular 5-HT levels measured under appropriate conditions are dependent on the concentration of Ca2+ or K+ in the perfusion fluid, is inhibited by tetrodotoxin, and is predominately neuronal in origin (45). In addition, specific neural processes can be measured after the local application of agents through the microdialysis probe, such as release after application of hypertonic KC1, rate of synthesis after synthesis inhibitors, or the local effects of drugs (46). This technique has made it possible to more accurately quantitate and characterize the... 

Q6 Pilocarpine eyedrops are suitable. In severe conditions, in addition to the eyedrops, intravenous acetazolamide and intravenous hypertonic mannitol (an osmotic agent) may be used to reduce pressure. Acetazolamide prevents the actions of carbonic anhydrase in the ciliary body and inhibits bicarbonate synthesis. This causes reduction in sodium transport and aqueous humour formation since there is a link between bicarbonate and sodium transport. 

Diphoterine is a product for chemical spatters on the eye and skin. Prevor Laboratory in France manufactures this odorless, colorless liquid dispensed as an eye wash or skin decontamination spray. It is composed of an aqueous solution to wash many chemical families and pull hydrophilic chemical agents away from the surface of tissues, an amphoteric solution that acts on acids and bases and restores the tissue physiological pH, and a hypertonic solution that stops penetration of corrosive chemicals into tissues. The pH is slightly alkaline (pH 1.2-1.1) and is sterile. Although not classified as such in the USA, it is classified as a medical device in Europe, Canada, Australia, and Brazil (www.prevor.com). 

Osmotherapy was introduced to ocular therapeutics in 1904 with the use of oral hypertonic saline to reduce elevated intraocular pressure.Topical ocular use of hyperosmotic agents has been proven clinically useful in the treatment of corneal edema, particularly when the cause is endothelial dysfunction. 

Sodium chloride is a component of all body fluids, including tears. A solution of 0.9% is approximately isotonic with tears. Of the various concentrations tested, 2% to 5% formulations have proven effective, with an irritation level acceptable to most patients. Studies comparing various hyperosmotic agents in human subjects have confirmed the usefulness of hypertonic sodium chloride in the treatment of corneal edema. Use of 5% sodium chloride in ointment form can be effective in reducing corneal thickness and in improving vision.The maximum reduction in corneal thickness occurs 3 to 4 hours after instillation of the ointment (Figure 15-1). 

Fatal cases of accidental overdosage have been reported in infants the complications leading to death were either pulmonary edema or convulsions. The latter can be due to hyperosmolarity (leading to hypertonic dehydration) or to the chemical toxicity of the contrast agent. 

Osmotic cathartics are hypertonic solutions that are absorbed poorly from the lumen of the intestine and draw water into the intestine by passive diffusion. The small intestine has a relatively low density of intercellular tight junctions and consequently should be most responsive to these osmotic agents. The large intestine, a target for osmotic cathartics and a frequent site of impactions of digesta, has a relatively high density of intercellular tight junctions and here the osmotic cathartics should be expected to have less effect. 

Dimethyl sulfoxide (DMSO) has also been suggested as a potent osmotic diuretic in horses. However, one study that compared the diuretic effects of DMSO with furosemide (frusemide, Img/kg) and hypertonic saline (5 liters) found that DMSO (Ig/kg administered i.v. diluted in 5 liters of 0.9% sodium chloride) was a relatively weak diuretic agent that doubled 4-h urine production in comparison with that achieved with the same volume of isotonic (0.9%) sodium chloride. The most dramatic diuretic response was produced by the hypertonic saline (7.5%), which resulted in the production of more than 40 ml/kg urine during the first 4-h period after administration (Schott Black 1995). 

DERMATOLOGICAL AGENT in a number of skin preparations, e.g. to treat eczema and psoriasis (as a hydrating agent). It can be given intravenously as a hypertonic dehydrating (osmotic) diuretic to reduce intracranial pressure in controlling cerebral oedema. 

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