Saline/fluid therapy

The tonicity of crystalloid solutions is directly related to their sodium concentration. The most commonly used crystalloids include normal saline, hypertonic saline, and lactated Ringer s solution. Excessive administration of any fluid replacement therapy, regardless of tonicity, can lead to fluid overload, particularly in patients with cardiac or renal insufficiency. 

When determining the appropriate fluid to be utilized, it is important to first determine the type of fluid problem (TBW versus ECF depletion), and start therapy accordingly. For patients demonstrating signs of impaired tissue perfusion, the immediate therapeutic goal is to increase the intravascular volume and restore tissue perfusion. The standard therapy is normal saline given at 150 to 500 mL/hour until perfusion is optimized. Although LR is a therapeutic alternative, lactic... 

Because the severity of symptoms and the absolute serum concentration are poorly correlated in some patients, institution of therapy should be dictated by the clinical scenario. All patients with hypercalcemia should be treated with aggressive rehydration normal saline at 200 to 300 mL/hour is a routine initial fluid prescription. For patients with mild hypocalcemia, hydration alone may provide adequate therapy. The moderate and severe forms of hypercalcemia are more likely to have significant manifestations and require prompt initiation of additional therapy. These patients may present with anorexia, confusion, and/or cardiac manifestations (bradycardia and arrhythmias with ECG changes). Total calcium concentrations greater than 13 mg/dL (3.25 mmol/L) are particularly worrisome, as these levels can unexpectedly precipitate acute renal failure, ventricular arrhythmias, and sudden death. 

Rest, fluids, humidified air, and nasal saline are the mainstays of nonpharmacologic therapy for the common cold. Pregnant women experiencing cold symptoms should be advised of these strategies and reminded that cold symptoms typically last only 7 to 10 days. 

Calciuric therapy in the form of hydration is a key component of the treatment of hypercalcemia, regardless of severity or presence of symptoms.28 Mild or asymptomatic patients may be encouraged to increase oral fluid intake (3-4 L/day). Patients with moderate to severe or symptomatic hypercalcemia should receive normal saline at 200 to 500 mL/hour according to dehydration and cardiovascular status. Patients should be encouraged to ambulate as much as possible because immobility enhances... 

Calciuric therapy Intravenous normal saline 200-500 mlZhour 24-48 hours 2-3 days 0.5-2 mg/dL Avoid fluid overload, monitor electrolytes. 

Patients with hypervolemic hypotonic hyponatremia should be treated with 3% saline and prompt initiation of fluid restriction. Loop diuretic therapy will also likely be required to facilitate urinary excretion of free water. 

Contraindications for antipsychotic therapy are few they may include Parkinson s disease, hepatic failure, hypotension, bone marrow depression, or use of CNS depressants. Overdoses of antipsychotics are rarely fatal, except for thioridazine, which is associated with major ventricular arrhythmias, cardiac conduction block, and sudden death. For other agents gastric lavage should be attempted even if several hours have elapsed since the drug was taken, because gastrointestinal motility is decreased and the tablets may still be in the stomach. Moreover, activated charcoal effectively binds most of these drugs and can be followed by a saline cathartic. The hypotension often responds to fluid replacement or pressor agents such as norepinephrine. 

The mainstay of medical treatment is fluid restriction, but this may not be appropriate in the surgical and critical care patient population. Severe (<120 mmol-L-l) or symptomatic hyponatraemia (mental status changes, seizure) requires more aggressive therapy to reduce cerebral oedema. Infusion of hypertonic saline to increase plasma sodium concentrations to 120-125 mmol L-1 alleviates symptoms. Adjunct therapy with demeclocycline (600 mg-day-1) may assist management in resistant SIADH. Demeclocycline is a tetracycline antibiotic which inhibits the actions of ADH at the renal tubules. 

The fundamental treatment for DKA includes aggressive intravenous hydration and insulin therapy and maintenance of potassium and other electrolyte levels. Fluid and insulin therapy is based on the patient s individual needs and requires frequent reevaluation and modification. Close attention has to be given to hydration and renal status, the sodium and potassium levels, and the rate of correction of plasma glucose and plasma osmolality. Fluid therapy generally begins with normal saline. Regular human insulin should be used for intravenous therapy with a usual starting dose of about 0.1 IU/kg/h. 

Sodium When patients present with hypernatremia and elevated serum osmolality, they are suffering from severe fluid deficits. Depending on the patient s hemodynamic stability, fluid therapy should generally be instituted as a moderate-to-slow intravenous infusion of 0.9% normal saline over a period of 48-72 h to avoid cerebral edema. Patients with evidence of circulatory compromise will require more aggressive fluid resuscitation. Estimated plasma osmolality and corrected serum sodium concentrations are calculated using the following formulas ... 

In two other trials, one in the United States and the other in Europe, DCLHb was tested in trauma and hemorrhagic shock patients as an adjunct to the current therapies for enhancing oxygen delivery fluids, blood, and operative intervention. In the multicenter, randomized, controlled, single-blinded efficacy trial conducted at 18 U.S. trauma centers from Feb 1997 to Jan 1998, patients with presumed or proven hemorrhage and persistent hypoperfusion were treated with DCLHb or normal saline (control) solution. Although there were no restrictions in the use of fluids, blood, or any other intervention prior to enrollment in this study, once enrolled, the patient received 500 ml of the treatment solution no later than 30 min after first... 

Bullous pemphigoid has been reported in an 84-year-old man after topical therapy with fluorouracil 1% solution daily over several days for actinic keratosis. All treated lesions became bullous, with the development of a few bullae on untreated areas of normal skin. Bullous lesions were pruritic and sore and some contained hemorrhagic fluid. There was a leukocytosis (11.7 x 10 /1). The blister fluid contained predominantly eosinophils, and immuno-fluorescent studies of the serum and blister fluid showed anti-basement membrane antibody titers of 1 640 and 1 160 respectively. Fluorouracil was discontinued and the patient was treated with steroids and saline compresses, with abatement of symptoms (119). 

Intravenous fluids clearly reduce the risk of AKI across a spectrum of etiologies. For example, in the prevention of contrast-induced nephropathy, one study compared IV hydration with 0.9% saline at 1 ml/kg/ hour beginning 12 hours prior to the study with unrestricted oral fluids. The incidence of AKI (as defined by a 0.5 mg/ dL or greater rise in serum creatinine) was 3.7% in the IV hydration group and 34.6% in the oral fluid group [95]. Saline-based therapies may not be as effective as a bicarbonate-based solution in this setting [96], however confirmation will be necessary from other centers. 

Some clinicians also advocate i.v. naloxone (an opioid antagonist) at 0.01-0.03 mg/kg for horses with life-threatening hemorrhages. The beneficial mechanisms of action of this therapy are not understood but it may act by increasing cardiac contractility. Aminocaproic acid, 20 g infused i.v. in 1 liter normal saline followed by 10 g in i.v. fluids every 6h, may be used to inhibit fibrinolysis. Blood transfusions may be indicated, especially in horses with extreme tachycardia or a packed cell volume <15%, which compromises the oxygenation of the myocardium. Following major and minor hemorrhage, cross-matched blood may be administered i.v. at a rate of 11/10 min. 

Hypervolemic patients are particularly problematic to manage acutely because the sodium and volume required to minimize the risk of cerebral edema or seizures may worsen their already compensated hepatic, cardiac, or renal function. It is generally agreed that these patients should be treated with hypertonic saline and prompt initiation of fluid restriction. Loop diuretic therapy will also likely be required to facilitate urinary excretion of free water. 

For those patients with normal to moderately impaired renal function, the cornerstone of initial treatment of hypercalcemia is volume expansion to increase urinary calcium excretion (see Table 49-6). Patients with severe renal insufficiency usually do not tolerate volume expansion they may be initiated on therapy with calcitonin. Patients with symptomatic hypercalcemia are often dehydrated secondary to vomiting and polyuria thus rehydration with saline-containing fluids is necessary to interrupt the stimulus for sodium and calcium reabsorption in the renal mbule. ° Rehydration can be accomplished by the infusion of normal saline at rates of 200 to 300 mL/h, depending on concomitant conditions (primarily cardiovascular and renal) and extent of hypercalcemia. Adequacy of hydration is assessed by measuring fluid intake and output or by central venous pressure monitoring. Loop diuretics such as furosemide (40 to 80 mg IV every 1 to 4 hours) or ethacrynic acid (for patients with sulfa allergies) may also be instiffited to increase urinary calcium excretion and to minimize the development of volume overload from the administration of saline (see Table 49-6). Loop diuretics such as furosemide... 

Regardless of the serotypes, the primary goal of therapy is restoration of fluid and electrolyte losses caused by watery diarrhea. ORT is the preferred method of rehydration, and several studies showed reduction in fluid requirements by 32% to 35% when rice-based instead of glucose-based ORT solutions are used (50-80 g rice instead of 20 g glucose per liter). In patients who cannot tolerate ORT, IV Ringer s lactate solution can be used. Normal saline is not recommended because it does not correct metabolic acidosis. After rehydration, maintenance fluid is given based on accurate recording of intake and output volumes. 

Drug delivery vehicles also may contain nutrients. Most intravenous therapies (maintenance intravenous fluids, drugs, and electrolyte replacements) are delivered using either dextrose (e.g., dextrose 5% in water) or sodium (e.g., 0.9% normal saline) in the admixture. Lipid emulsion (10%) is used as the vehicle for the anesthetic... 

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