Balance fluid/electrolyte

Ovarian hormones influence fluid intake by interaction with the brain renin-angiotensin system and it has been shown that gonadal steroids affect brain fluid-electrolyte balance by interactions with vasopressin. Both hyperos-molarity and increased intracranial pressure stimulate vasopressin release and intraperitoneal administration of vasopressin antagonists decrease brain volume. 

The ICH S7A states that the effects of the NCE on renal parameters should be assessed for example, urinary volume, specific gravity, osmolality, pH value, fluid/electrolyte balance, proteins, cytology, and blood chemistry determinations such as blood urea... 

Fluid/Electrolyte balance Perform initial and periodic determinations of serum... 

Diarrhea Diphenoxylate may prolong or aggravate diarrhea associated with organisms that penetrate intestinal mucosa (ie, toxigenic Escherichia coli, Salmonella, Shigella) or in pseudomembranous enterocolitis associated with broad-spectrum antibiotics. Do not use diphenoxylate in these conditions. In some patients with acute ulcerative colitis, diphenoxylate may induce toxic megacolon. Fluid/Electrolyte balance Dehydration, particularly in younger children, may... 

While there are no absolute contraindications to lithium, patients with advanced kidney disease or unstable fluid/ electrolyte balance may be more safely treated with an alternative mood stabilizer, such as carbamazepine, valproate, lamotrigine, or olanzapine. 

Drugs that can disturb fluid-electrolyte balance must be used with caution in patients with certain types of liver impairment. Diuretics, for example, are often required to treat ascites but can cause hypo-natraemia, hypo- or hyperkalaemia. A disturbance in electrolyte balance can lead to encephalopathy in susceptible patients such as cirrhotics or those with acute liver failure. Dehydration induced by diuretics is a common precipitant of hepatic encephalopathy. The mechanism is not fully understood, but could possibly be due to the reduced metabolism of hepatic toxins because of hepatic hypoxia [5]. 

A patient must take in 1900 to 2400 ml of fluid per day maintain fluid-electrolyte balance. Age and medical conditions influence the daily amount of water. Disease and its treatment increase water output, requiring an increased water intake. A fever causes the loss of 2185 to 2760 ml of water each day. 

How much fluid per day must be taken in to maintain fluid-electrolyte balance ... 

A patient must take in 1900 to 2400 ml of fluid per day to maintain fluid-electrolyte balance. 

The use of intravenous fluids may fail to correct the fluid - electrolyte balance, and the therapy may give rise to further problems if it is not monitored closely. This should... 

Extracellular fluid (ECF) is divided into smaller compartments. These spaces between the cells are called the interstitial space. The space is occupied by plasma and lymph, transcellular fluid, and fluid in the bone and connective tissues. This makes up 20% of body weight. About a third is plasma and two thirds of extracellular fluid is in the space between the cells. Transcellular fluid is also ECF but is found in the gastrointestinal (GI) tract, cerebrospinal space, aqueous humor, pleural space, synovial space, and the peritoneal space. Although fluid in the transcellular space is a small volume when compared with intracellular and extracellular compartments, the increase or decrease in volumes in transcellular spaces can have a dramatic effect on the fluid-electrolyte balance. 

This means that each day the patient must take in between 1900 mL and 2400 mL of fluid in order to maintain fluid-electrolyte balance. However, disease and the treatment of disease can increase the patient s output of water requiring that the patient increase the intake of water. 

Sodium, potassium, and chloride, as ions (Na, K, and Gl ), are essential to electrolyte balance in body fluids. Electrolyte balance, in turn, is essential for fluid balance, acid-base balance, and transmission of nerve impulses. Table salt is the principal source of sodium and chloride ions, and dietary deficiencies are unlikely. When there is extreme fluid loss through vomiting, diarrhea, or traumatic injury, electrolytes must be supplied to restore their concentration in body fluids. 

If cells are to survive and function normally, the fluid medium in which they live must be in equilibrium. Fluid and electrolyte balance, therefore, implies constancy, or homeostasis. This means that the amount and distribution of body fluids and electrolytes are normal and constant. For homeostasis to be maintained, the water and electrolytes that enter (input) the body must be relatively equal to the amount that leaves (output). An imbalance of osmolality, the amount of force of solute per volume of solvent (measured in miliosmoles per kilogram—mOsm/kg or mmol/ kg), of this medium can lead to serious disorders or even death. Fortunately, the body maintains homeostasis through a number of self-regulating systems, which include hormones, the nervous system, fluid-electrolyte balance, and acid-base systems. Els... 

Armstrong LE (2002) Caffeine, body fluid-electrolyte balance and exercise performance. International Journal of Sport Nutrition and Exercise Metabolism 12 205-222. 

Corticosteroids exhibit a wide range of physiological effects One important func tion IS to assist m maintaining the proper electrolyte balance m body fluids They also play a vital regulatory role m the metabolism of carbohydrates and m mediating the alter gic response... 

As we have seen in this chapter steroids have a number of functions in human physiology Cholesterol is a component part of cell mem branes and is found in large amounts in the brain Derivatives of cholic acid assist the digestion of fats in the small intestine Cortisone and its derivatives are involved in maintaining the electrolyte balance in body fluids The sex hormones responsible for mascu line and feminine characteristics as well as numerous aspects of pregnancy from conception to birth are steroids... 

The integrity of mammalian kidneys is vital to body homeostasis, because the kidneys play the principal role in the excretion of metabolic wastes and the regulation of extracellular fluid volume, electrolyte balance, and acid-base... 

Saltin, B. Costill, D.L. (1988). Fluid and electrolyte balance during prolonged exercise. In Exercise, Nutrition, and Energy Metabolism (Horton, E.S. Teijung, R.L., ed), pp. 150-158, MacMillan. New York. 

From the above, derives the fundamental concept that the newborn infant must be maintained in an adequate degree of hydration and in electrolyte balance in order for the infant to thrive. In some cases, where for one reason or other, the infant is not able to take fluids by mouth in the normal manner, one may need to resort to supplementary fluid therapy by vein. For a rational approach to this problem one needs to have available from the clinical chemical laboratory> rapid response in order to continuously monitor changes in electrolyte levels so that fluids can be modified so as to correct these abnormal-ities. 

Because disturbances in fluid balance are routinely encountered in clinical medicine, it is essential to have a thorough understanding of body fluid compartments and the therapeutic use of fluids. Similarly, disturbances in serum sodium, potassium, calcium, phosphorus, and magnesium are ubiquitous and must be mastered by all clinicians. Dysregulation of fluid and/or electrolyte status has serious implications regarding the concepts of drug absorption, volumes of distribution, and toxicity. Similarly, many medications can disrupt fluid and/or electrolyte balance as an unintended consequence. 

The posterior pituitary is innervated by direct nervous stimulation from the hypothalamus, resulting in the release of specific hormones. The hypothalamus synthesizes two hormones, oxytocin and vasopressin. These hormones are stored in and released from the posterior pituitary lobe. Oxytocin exerts two actions (1) it promotes uterine contractions during labor, and (2) it contracts the smooth muscles in the breast to stimulate the release of milk from the mammary gland during lactation. Vasopressin is an antidiuretic hormone (ADH) essential for proper fluid and electrolyte balance in the body. Specifically, vasopressin increases the permeability of the distal convoluted tubules and collecting ducts of the nephrons to water. This causes the kidney to excrete less water in the urine. Consequently, the urine becomes more concentrated as water is conserved. 

Commonly administered LVPs include such products as Lactated Ringers Injection USP, Sodium Chloride Injection USP (0.9%), which replenish fluids and electrolytes, and Dextrose Injection USP (5%), which provides fluid plus nutrition (calories), or various combinations of dextrose and saline. In addition, numerous other nutrient and ionic solutions are available for clinical use, the most popular of which are solutions of essential amino acids or lipid emulsions. These solutions are modified to be hypertonic, isotonic, or hypotonic to aid in maintaining both fluid, nutritional, and electrolyte balance in a particular patient according to need. Indwelling needles or catheters are required in LVP administration. Care must be taken to avoid local or systemic infections or thrombophlebitis owing to faulty injection or administration technique. 

The kidneys are organs specialized to filter the blood. As such, they make an important contribution to the removal of metabolic waste products as well as to maintenance of fluid and electrolyte balance. Specific functions of the kidneys include ... 

Renal replacement therapy (RRT), such as hemodialysis and peritoneal dialysis, maintains fluid and electrolyte balance while removing waste products. See Table 75-4 for indications for RRT in ARF. Intermittent and continuous options have different advantages (and disadvantages) but, after correcting for severity of illness, have similar outcomes. Consequently, hybrid approaches (e.g., sustained low-efficiency dialysis and extended daily dialysis) are being developed to provide the advantages of both. 

Corticosteroids synthesized by the adrenal gland are mineralocorticoids and GC. Min-eralocorticoids regulate fluid and electrolyte balance by affecting ion transport in the kidney. Cortisol, the primary circulating GC in most species (including humans), has many activities, including resistance to stress, regulation of intermediary metabolism, and immunosuppressive and anti-inflammatory effects. GC synthesis and secretion is... 

Medical Management No specific viral therapy exists so treatment is supportive only. Treat patients with uncomplicated VEE infection with analgesics to relieve headache and myalgia. Patients who develop encephalitis could require anticonvulsants and intensive care to maintain fluid and electrolyte balance, ensure adequate ventilation, and avoid complicating secondary bacterial infections. Patients should be treated in a screened room or in quarters treated with residual insecticide for at least five days after onset, or until afebrile (without fever) to foil mosquitoes since humans may remain infectious for mosquitoes for at least seventy-two hours. Isolation and qaurantine is not required. Standard Precautions should be practiced when dealing with infection control for VEE victims as shown below ... 

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