Volume overload treatment

The problem is made more difficult because these different dispersion processes are interactive and the extent to which one process affects the peak shape is modified by the presence of another. It follows if the processes that causes dispersion in mass overload are not random, but interactive, the normal procedures for mathematically analyzing peak dispersion can not be applied. These complex interacting effects can, however, be demonstrated experimentally, if not by rigorous theoretical treatment, and examples of mass overload were included in the work of Scott and Kucera [1]. The authors employed the same chromatographic system that they used to examine volume overload, but they employed two mobile phases of different polarity. In the first experiments, the mobile phase n-heptane was used and the sample volume was kept constant at 200 pi. The masses of naphthalene and anthracene were kept... 

The mainstay of treatment for vaso-occlusive crisis includes hydration and analgesia (see Table 65-7). Pain may involve the extremities, back, chest, and abdomen. Patients with mild pain crises may be treated as outpatients with rest, warm compresses to the affected (painful) area, increased fluid intake, and oral analgesia. Patients with moderate to severe crises should be hospitalized. Infection should be ruled out because it may trigger a pain crisis, and any patient presenting with fever or critical illness should be started on empirical broad-spectrum antibiotics. Patients who are anemic should be transfused to their baseline. Intravenous or oral fluids at 1.5 times maintenance is recommended. Close monitoring of the patient s fluid status is important to avoid overhydration, which can lead to ACS, volume overload, or heart failure.6,27... 

Hydration and analgesics are the mainstays of treatment for vasoocclusive (painful) crisis. Fluid replacement should be 1.5 times the maintenance requirement, can be administered IV or orally, and should be monitored to avoid volume overload. An infectious etiology should be considered if appropriate, empiric therapy should be initiated. 

The use of vincristine to treat thrombotic thrombocytopenic purpura has also been reported to be successful 14,18). This rare disease of sporadic thrombosis of small vessels with consequent intravascular hemolysis has been successfully treated recently with both plasma exchange and plasma infusion. However, there are obvious disadvantages to plasma infusion, including volume overload, transmission of infection, and cost and scarcity of plasma. Several patients have been successfully treated with vincristine alone or in association with plasma therapy. At present, however, this treatment should probably not be used alone because of the high success rate of plasma infusion and/or exchange. 

In mild cases of hyponatremia, treatment typically focuses on water restriction (< 800 mL/day) however this approach suffers from poor patient compliance due to thirst brought on by increasing serum osmolality.1,10 In cases of extreme hyponatremia, infusions of hypertonic saline are used to elevate serum sodium concentrations. Loop diuretics (e.g., furosemide) are often used as an adjunct to such treatment to offset potential volume overload.1 Hypertonic saline therapy is also suboptimal, as it carries a risk of overly rapid adjustment of plasma sodium levels, which can result in the rapid shift of water from brain tissue to the vascular space, triggering neural demyelination that can result in seizures, coma, quadriplegia, and even death.1... 

Intravenous immunoglobulin expands the plasma volume and increases blood viscosity, which can lead to volume overload in patients with cardiac insufficiency (41). Stroke, thromboembolic events, and myocardial infarction have been reported after high-dose treatment with intravenous immunoglobulin, which increases plasma viscosity (41 3). 

The initial effort in the treatment of DHF is aimed at decreasing symptoms. The first step in this effort is to decrease pulmonary congestion by decreasing LV volume using sodium and fluid restriction. A low-sodium diet (<2 g/day) and moderate fluid restriction will help to prevent volume overload. Both sodium and fluid restriction must be done with care. Excessive restriction can lead to hypotension, low-output state, and/or renal insufficiency. Daily weights may help to assess volume status. Dietary and lifestyle factors that decrease the risk of development of epicardial CAD and high blood pressure should be encouraged. 

Patients with DHF may present with an acute onset of pulmonary edema. There are a number of potential causes for the acute decompensation of these patients, including volume overload, uncontrolled hypertension, acute myocardial ischemia, progressive valvular disease (aortic stenosis), and new-onset or uncontrolled tachyarrhythmias. Treatment strategies for these patients eventually may include the need for surgery, as in the case of valvular disease. 

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... 

Diuretics are used clinically to treat hypertension (see Chapter 32) and to reduce edema associated with cardiac, renal, and hepatic disorders. Three fundamental strategies exist for mobilizing edema fluid correct the underlying disease, restrict Na intake, or administer diuretics. The most desirable course of action would be to correct the primary disease however, this often is impossible. Restriction of Na+ intake is the favored nonpharmacologic approach to the treatment of edema and hypertension and should be attempted however, compliance is a major obstacle. Diuretics therefore remain the cornerstone for the treatment of edema or volume overload, particularly that owing to congestive heart failure, ascites, chronic renal failure, or nephrotic syndrome. 

Patients with diastolic heart failure are typically dependent upon preload to maintain adequate cardiac output. While patients with symptomatic volume overload will benefit from careful modulation of intravascular volume, volume reduction should be accomplished gradually and treatment goals reassessed frequently. In addition to cautious volume management, it is important to maintain synchronous atrial contraction in such patients, which maintains adequate left ventricular filling during the latter phase of diastole. Cardiac function is often severely impaired if patients with diastolic heart failure develop atrial fibrillation, particularly in the context of sub-optimal ventricular rate control. Meticulous control of the ventricular rate with drugs that slow AV conduction is mandatory (see Chapter 34) and restoration of sinus rhythm should be considered. It is also important to evaluate and treat conditions that are associated with dynamic abnormalities of diastolic function, such as myocardial ischemia and poorly controlled systemic hypertension. 

If ICP monitoring is performed, rapid and abrapt increases of intracranial pressure can be directly addressed by the infusion of mannitol, for example, or the application of ranitidine. In most patients, however, the management of raised intracranial pressure has to be performed without actual information on its severity. Thus, general rules are followed, such as elevation of the head of the bed to 30 degrees, sedation, minimal stimulation or the administration of mannitol three times a day. Mannitol has been shown to improve survival in a group of patients with acute liver failure (Canalese et al., 1982). If renal failure accomplishes acute liver failure, however, a paradoxical effect can occur with mannitol treatment as serum osmolality increases and volume overload may occur. Therefore plasma osmolality must be checked at least twice a day to assure that it remains <320 mos-mol/1 (Poison and Lee, 2005 Rinella and Sanyal, 2006). 

Indications for renal replacement therapy in the acute setting and for other disease processes are different from those for ESRD. A common mode of ESRD therapy in the outpatient setting is intermittent hemodialysis (IHD) where a patient receives intense treatment over the course of a few hours several times a week. Acute renal failure in the inpatient setting is often treated with continuous renal replacement therapy (CRRT), which is applied for the entire duration of the patient s clinical need and relies upon hemofiltration to a higher degree than IHD (Meyer, 2000). Other nonrenal indications for CRRT are based on the theoretical removal of inflammatory mediators or toxins and elimination of excess fluid (Schetz, 1999). These illnesses include sepsis and systemic inflammatory response syndrome, acute respiratory distress syndrome, congestive heart failure with volume overload, tumor lysis syndrome, crush injury, and genetic metabolic disturbances (Schetz, 1999). 

The nurse should monitor for patient response to treatment, particularly noting laboratory values and vital signs. It is most important to monitor intake and output and to note signs of hypovolemia that might occur if the degree of volume overload is overestimated and the treatment is excessive. Hold diuretics until the primary-care provider is consulted. 6... 

Treatment of sodium overload consists of administration of loop diuretics to facilitate excretion of the excess sodium, as well as intravenous D5W. The latter should be infused at a rate that will decrease the serum sodium at approximately 0.5 mEq/L per hour, or 1 mEq/L per hour in cases in which the hypernatremia developed rapidly over several hours. ° The volume of infusate may be estimated as described previously. Furosemide should be administered at a dose of 20 to 40 mg intravenously every 6 hours. 

Fluid balance Because FFP contains low concentrations of coagulation factors, large volumes may be needed when FFP is used to reverse excess oral anticoagulation treatment, with a risk of fluid overload [31 32 33 34, 35 ]. 

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