Hyperosmolarity glucose

Three elements of a parenteral nutrition support therapy preparation are hyperosmolar glucose, amino acids, and vitamins. 

These patients receive an infusion of a solution that contains hyperosmolar glucose, amino acids, vitamins, electrolytes, minerals, and trace elements. In addition, the patient might be given fat emulsion supplemental therapy to increase the number of calories and to receive fat-soluble vitamins. The infusion is given through a central venous hne such as the subclavian or internal jugular vein to prevent irritation to the peripheral veins. 

Hyperglycemic hyperosmolar nonketotic syndrome Severe increase in serum glucose concentration without the production of ketones, leading to an increase in serum osmolality and symptoms... 

A specific complication of the use of large amounts of insulin during hyperosmolar diabetic coma is rhabdomyo-lysis (123). Low intramuscular phosphate and potassium concentrations, often masked by relatively high blood glucose concentrations, may be important contributory factors. 

Hyperosmolar diabetic coma occms chiefly in noninsulin-dependent diabetics who fail to compensate for their continuing, osmotic glucose diuresis. It is characterised by severe dehydration, a very high blood sugar (> 33 mmol/1 600 mg/100 ml) and lack of ketosis and acidosis. Treatment is with isotonic (0.9%) saline, at half the rate recommended for ketoacidotic coma, and with less potassium than in severe ketoacidosis. Insulin requirements are less than in ketoacidosis, where the acidosis causes resistance to the actions of insuhn, and should generally be half those shown in Table 35.2. Patients are more liable to thrombosis and prophylactic heparin is used. 

Diabetes mellitus is a group of metabolic diseases characterized by an increased blood glucose level secondary to defects in insulin secretion and/or action. According to the American Diabetes Association, as of 2002, the United States diabetes prevalence is 18.2 million people (6.3% of the population). Diabetics suffer from acute complications of the disease such as diabetic ketoacidosis and hyperosmolar nonketotic syndrome as well as chronic complications ranging from microvascular disease (nephropathy, neuropathy, retinopathy) to macrovascular disease (1). 

If blood glucose levels continued to rise after a meal, the high concentration of glucose would cause the release of water from tissues as a result of the osmotic effect of glucose. Tissues would become dehydrated, and their function would be affected. A hyperosmolar coma could result from dehydration of the brain. 

Keywords Diabetic ketoacidosis, hyperosmolar hyperglycemia, ketone bodies, glucose, insulin, fluid and electrolyte therapy. 

Another condition, less common, that could result from decreased insulin availability or effectiveness also involves the excess buildup of glucose. This condition, referred to as hyperosmolar hyperglycemic syndrome (HHS), is an extreme hyperglycemia without the development of ketones. Similar to DKA, HHS results in an osmotic diuresis with loss of fluids in the urine along with a loss of electrolytes. 2 4... 

As is the case for the pH level and buffer capacity, adjustment of osmotic value to physiological conditions is advisable. Sodium chloride or glucose are mostly used to adjust tonicity of parenterals. Sometimes deviating medical requirements are to be met. For example, hyperbaric solutions of local anaesthetics are used in spinal anaesthesia (see Sect. 13.2.4). Hyperbaricity in comparison to the cerebrospinal fluid is achieved by a high glucose concentration (7.5 %) which is also a hyperosmolar. 

Parenteral nutrition admixtures are hypertonic. Glucose, amino acids and electrolytes induce a hyperosmolar (1,300-1,800 mOsm/L) infusion solution. 

Hyperosmolar coma with extremely high concentrations of blood glucose (often accompanied by a concomitant hypernatremia) may occasionally be seen during the course of total parenteral nutrition, particularly if adequate monitoring is not carried out. This complication has been implicated in several fatalities of total parenteral nutrition. 

IGFs, lipoproteins, and insulin are abundant in plasma under normal conditions. Thus, it is possible that these factors are also important in vivo (11,286,288,289) this concept was examined by taking platelet extract from humans and exposing it to rat aortic VSMCs. It caused proliferation of these cells, an effect that was more pronounced when the extract from diabetic vs normal subjects was used (290). Moreover, this increased proliferative effect by the platelet extract fiom diabetic patients was markedly reduced after treatment to normalize plasma glucose. This adds further support to the notion that either hyperosmolarity or some factor other than insulin contributes to the development of the atherosclerotic process. The AGE-receptor for AGE interaction in VSMC, in addition to growth factors induced by AGE, contributes to the stimulatory effects of diabetic sera on VSMC proliferation that can accelerate atherosclerosis (291). 

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