Oral replacement solutions

It is possible to treat moderately dehydrated horses effectively with oral replacement solutions (ORSs) (McGinness et al 1996). Oral fluids do not need to be sterUe and can be made up on the farm they are, therefore, considerably cheaper and easier to transport than i.v. fluids. It is apparently not necessary to add glucose to oral fluids for horses (Sosa Leon et al 1995) but, if feasible, electrolytes should be added. Isotonic or hypotonic fluids should be adnunistered (Sosa Leon et al 1995). A possible isotonic solution consists of 4.9 g/1 table salt and... 

Sodium content for oral replacement solutions should be between 50 and 90 mEq/L for initial rehydration. The American Academy of Pediatrics (AAP) recommends rehydration with a more electrolyteconcentrated rehydration phase and a subsequent maintenance phase using the more dilute solutions and larger volume (see Table 111-1). In children with vomiting and diarrhea, ORT may be given as 5 mL... 

Oral electrolyte solutions contain a carbohydrate and various electrolytes. Examples of combined oral electrolyte solutions are Pedialyte and Rehydralyte. Oral electrolyte solutions are most often used to replace lost electrolytes, carbohydrates, and fluid in conditions such as severe vomiting or diarrhea... 

Mineral balance Hypernatremia, hypokalemia, and acidosis have been reported after incorrect administration of oral rehydration solutions to two infants [lOS ]. In both cases the parents had diluted 21 g of each oral rehydration solution packet in 200 ml of water. In one case the electrolyte abnormalities were corrected and the losses were replaced with properly reconstituted oral rehydration solution. In the other case there was severe dehydration and the child died. 

Combined electrolyte solutions are available for oral and IV administration. The IV solutions contain various electrolytes and dextrose. The amount of electrolytes, given as milliequivalents per liter (mEq/L), also varies. The IV solutions are used to replace fluid and electrolytes that have been lost and to provide calories by means of their carbohydrate content. Examples of IV electrolyte solutions are dextrose 5% with 0.9% NaCl, lactated Ringer s injection, Plasma-Lyte, and 10% Travert (invert sugar—a combination of equal parts of fructose and dextrose) and Electrolyte No. 2. 

Intravenous (i.v.) solutions are commonly administered to patients in hospitals, long-term care facilities, and ambulances. They are used primarily to replace body fluids and to serve as a vehicle for injecting drugs into the body. The advantages of this pharmaceutical dosage form include the rapid onset of action, the ability to treat patients unable to take medication orally and the ability to administer a medication unavailable in any other dosage form. 

Hyponatremia - For parenteral restoration of sodium ion in patients with restricted oral intake. Sodium replacement is specifically indicated in patients with hyponatremia or low salt syndrome. Sodium chloride may also be added to compatible carbohydrate solutions such as dextrose in water to provide electrolytes. 

In general, a normal diet plus about 40 mEq per day of K+ is adequate to prevent hypokalemia. If K+-rich foods prove inadequate in replacing large quantities of the electrolyte or if the increased caloric intake that is part of the dietary supplementation is not desirable, oral liquid therapy is the formulation of choice. A listing of these solutions is given in Table 21.4. Although patients may find many of fhese products unpalatable, their further dilution with water or fruit juice can be... 

As a rule, when quinolones are administered orally, their absorption from the gastrointestinal tract is rapid and almost complete, but food in the stomach delays their absorption. In unweaned calves, fluoroquinolones are often given in the milk replacer, but oral bioavailability is slightly reduced compared with the oral drench (139). On tire other hand, fermentation in the rumen of mature ruminants precludes the oral use of fluoroquinolones. Injectable solutions are also available for systemic therapy of large animals and turkeys. 

Metabolic acidosis involves a build-up of hydrogen ions in the blood, thus lowering blood pH. Under normal physiological conditions, the kidneys excrete excess hydrogen ions, and release more bicarbonate ions into the bloodstream to buffer the excess acid. However, in renal failure, or in diabetic ketoacidosis, this mechanism either fails, or is unable to compensate to an adequate extent. Hence, metabolic acidosis is usually treated with sodium bicarbonate, either intravenously (1.26% or 8.4% i.v. solution) or orally (typically 1 g three times a day). Sodium bicarbonate 1.26% intravenous solution is isotonic with plasma (and with sodium chloride 0.9%), so may be given in large volumes (1-2 L) by peripheral venous catheter to correct metabolic acidosis and provide fluid replacement at the same time. Sodium bicarbonate 8.4% may only be given by central venous catheter. 

Vibrio cholerae. The cause of death in cholera is electrolyte and fluid loss in the stools and this may exceed 11/h. The most important aim of treatment is prompt replacement and maintenance of water and electrolytes with oral or intravenous electrolyte solutions. Doxycycline, given early, significantly reduces the amount and duration of diarrhoea and eliminates the organism from the faeces (thus lessening the contamination of the environment). Carriers may be treated by doxycycline by mouth in high dose for 3 days. Ciprofloxacin may be given for resistant organisms. 

The usual oral starting dose to replace a weaker analgesic, e.g. co-proxamol, is 2.5-10 mg 4-hourly (2.5 mg in the frail elderly) of the aqueous solution or 10-30 mg 12-hourly of the sustained-release formulations. Alternatively, use suppositories or buccal (sublingual) formulations (the latter route bypasses the presystemic elimination and does not require such high doses as when swallowed). 

Oral rehydration therapy (ORT) with glucose-electrolyte solution is sufficient to treat the vast majority of episodes of watery diarrhoea from acute gastroenteritis. As a simple, effective, cheap and readily administered therapy for a potentially lethal condition, ORT must rank as a major advance in therapy. It is effective because glucose-coupled sodium transport continues during diarrhoea and so enhances replacement of water and electrolyte losses in the stool. 

Ritonavir, an HIV protease inhibitor with peptidelike structure, has an intrinsic water solubility of l.Opg/ml. Norvir is a thermodynamically stable solution formulation containing 100 mg of ritonavir dissolved in a mixture of oleic acid, Cremophor EL, ethanol, and the antioxidant butylated hydroxytoluene (BHT), and filled into soft gelatin capsules. However, Norvir is being replaced by Kaletra oral solution and soft gelatin capsule, which is a combination of 133.3 mg of lopinavir and 33.3 mg ritonavir dissolved in a mixture of oleic acid, polyoxyl 35 castor oil (Cremophor EL), and propylene glycol. The water-insoluble HIV protease inhibitor, saquinavir, is solubilized by a mixture of Vitamin E and medium-chain mono- and diglycerides in 200 mg Fortovase soft gelatin capsules. 

Maintenance of the volume of the circulatory system is dependent on sodium ions and water. Oral rehydration therapy may involve drinking a solution of 90 mM NaCl. Replacing K and HCO3 may be a vital concern as well, though they are secondary to water and sodium. Diarrhea can result in acidosis because of the bicarbonate secreted into the lumen and the concomitant delivery of protons to the plasma. Hence, bicarbonate may be included during rehydration therapy to reverse acidosis. Acidosis is defined as a plasma pH less than 7.10. Generally, serious and life-threatening acidosis does not occur with mild or moderate cases of diarrhea. 

Oral fluids can be a successful alternative or adjunct to i.v. fluids in many mildly dehydrated horses with large colon impactions (Lopes et al 1999). Unfortunately, oral fluids are insufficient for moderately to severely dehydrated horses rapid administration of a glucose- and glycine-containing electrolyte solution (81/30 min) resulted in incomplete fluid absorption in horses with castor oil-induced diarrhea (Ecke et al 1998). The ORSs available commercially may not be ideal for fluid replacement in horses (Ecke et al 1998). Further research is necessary to refine oral fluid therapy for horses. 

Replace fluids orally with an electrolyte solution. 

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