Fluid balance

Table 11 summarizes values for the median lethal dose (LD q) for several species. In case of massive exposure, convulsions must be controlled, and glucose, fluid balance, and uriaary output must be maintained. Medical surveillance requires checking for damage to the Hver, the organ that apparently sustains initial damage, and monitoring for changes ia the blood profile. 

When a particle falls under the influence of gravity it will accelerate until the frictional drag in the fluid balances the gravitational forces. At this point it will continue to fall at constant velocity. This is the terminal velocity or free-settling velocity. The general formulae for any shape particle are [13] ... 

The nurse should encourage the patient with diarrhea to drink fluids to replace those lost with the diarrhea. It is important to maintain an accurate intake and output record to help determine fluid balance... 

Treatment of barbiturate toxicity is mainly supportive (ie, maintaining a patent airway, oxygen administration, monitoring vital signs and fluid balance). The patient may require treatment for shock, respiratory assistance, administration of activated charcoal, and in severe cases of toxicity, hemodialysis. 

Along with a disturbance in fluid volume (eg, loss of plasma, blood, or water) or a need for providing parenteral nutrition with the previously discussed solutions, an electrolyte imbalance may exist. An electrolyte is an electrically charged substance essential to the normal functioning of all cells. Electrolytes circulate in the blood at specific levels where they are available for use when needed by the cells. An electrolyte imbalance occurs when the concentration of an electrolyte in the blood is either too high or too low. In some instances, an electrolyte imbalance may be present without an appreciable disturbance in fluid balance For example, a patient taking a diuretic is able to maintain fluid balance by an adequate oral intake of water, which... 

Occasionally, patients with HF do not respond to a diuretic, defined as failure to achieve a weight reduction of at least 0.5 kg (or negative net fluid balance of at least 500 mL) after several increasing bolus doses.17... 

In PD, prewarmed dialysate is instilled into the peritoneal cavity where it dwells for a specified length of time (usually one to several hours, depending on the type of PD) to adequately clear metabolic waste products. At the end of the dwell time, the dialysate is drained and replaced with fresh dialysate. The continuous nature of PD provides for a more physiologic removal of waste products from the bloodstream, which mimics endogenous renal function by decreasing the fluctuations seen in serum concentrations of the waste products. Similarly, water is removed at a more constant rate, lessening the fluctuations in intravascular fluid balance and providing for more hemodynamic stability. 

To maintain fluid balance, the total amount of fluid gained throughout the day (input, or ins ) must equal the total amount of fluid lost (output, or outs ). Although most forms of the body s input and output can be measured, several cannot. For... 

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. 

Aldosterone (183) is one of the key steroid hormones involved in regulation of the body s mineral and fluid balance. Excess levels of this steroid quickly lead to marked retention of sodium chloride, water and, often as a consequence, hypertension. The aldosterone antagonist spironolactone (184) has proven of great clinical value in blocking the effects... 

CFD models for turbulent multiphase reacting flows do not solve the laminar two-fluid balances (Eqs. 164 and 165) directly. First, Reynolds averaging is applied to eliminate the large-scale turbulent fluctuations. Using Eq. (164) as an example, we can apply Reynolds averaging to find (with pg constant)... 

The white blood cell count, fluid balance, and electrolyte concentrations usually remain normal unless fluids and electrolytes are lost due to vomiting and diarrhea. 

In the initial hour of treatment, a large volume of IV solution (lactated Ringer s solution) may need to be administered to restore intravascular volume. This may be followed by up to 1 L/hour until fluid balance is restored in a few hours. 

Micronutrients are required to support metabolic activities for cellular homeostasis such as enzyme reactions, fluid balance, and regulation of electrophysiologic processes. 

Cyclic PN (e.g., 12 to 18 hours/day) is useful in hospitalized patients who have limited venous access and require other medications necessitating interruption of PN infusion, to prevent or treat hepatotoxicities associated with continuous PN therapy, and to allow home patients to resume normal lifestyles. Patients with severe glucose intolerance or unstable fluid balance may not tolerate cyclic PN. 

Current nutritional intake Complete blood cell count Serum electrolytes Sodium Potassium Chloride Bicarbonate Magnesium Phosphorous Calcium Serum glucose Serum albumin Markers for organ function Liver function tests Alkaline phosphatase Aspartate aminotransferase Alanine aminotransferase Total bilirubin Prothrombin time or International normalized ratio Renal function tests Blood urea nitrogen Creatinine Fluid balance Input Oral... 

When large volumes (i.e., more than a liter) of fluid are injected (such as in peritoneal dialysis, hyperalimentation, fluid replacement, and other conditions). Special consideration of fluid balance must be given to patients receiving large volumes, as well as careful consideration of the systemic effects of injection fluid components (e.g., amino acids and their nephrotoxicity). 

While most lipophilic and large molecules are primarily excreted by the hepatobiliary system, the kidney is the major excretory organ for many small organic and inorganic molecules, drugs and hydrophilic metabolites, maintenance of fluid balance, and bone metabolism. These functions expose the kidney to a number of clinical, physiological, and pathological conditions that may compromise renal function. Some renal disorders that necessitate clinical intervention are listed in Table 2. 

Monitoring Monitor changes in fluid balance, electrolyte concentrations, and acid-base balance during prolonged parenteral therapy or whenever the condition of the patient warrants such evaluation. Significant deviations from normal concentrations may require tailoring of the electrolyte pattern. 

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