Mannitol pulmonary edema

Mannitol is rapidly distributed in the extracellular compartment and extracts water from cells. Prior to the diuresis, this leads to expansion of the extracellular volume and hyponatremia. This effect can complicate heart failure and may produce florid pulmonary edema. Headache, nausea, and vomiting are commonly observed in patients treated with osmotic diuretics. 

Mannitol, the most commonly employed osmotic diuretic, is a large polysaccharide molecule. It is often selected for use in the prophylaxis or treatment of oliguric ARF. It is not absorbed from the gastrointestinal tract and, therefore, is only administered i.v. with its elimination dependent on the GFR (within 30 to 60 min with normal renal function). Mannitol is distributed within the plasma and extracellular fluid spaces and produces an increase in the serum osmolality and expansion of the circulating volume. It is not generally used for the treatment of edema because any mannitol retained in the extracellular fluid can promote further edema formation. Furthermore, acute plasma volume expansion may challenge individuals with poor cardiac contractility and can precipitate pulmonary edema. Mannitol is commonly administered for the treatment of cerebral edema consequent to head trauma or to hypoxic-ischemic encephalopathy in neonatal foals. Because mannitol promotes water excretion, hypernatremia is a potential complication in patients that do not have free access to water (Martinez-Maldonado Cordova 1990, Wilcox 1991). 

Mannitol is the most frequently prescribed osmotic diuretic. The side effects and adverse reactions include fluid and electrolyte imbalance, pulmonary edema from rapid shift of fluids, nausea, vomiting, tachycardia from rapid fluid loss, and acidosis. 

C. In the past, mannitol had been used to induce forced diuresis for some poisonings (eg, phenobarbital, salicylate) to enhance their renal elimination, but has been abandoned due to lack of efficacy and potential risks (cerebral and pulmonary edema). 

A. Mannitol may cause excessive expansion of intravascular space when administered in high concentrations at a rapid rate. This may result in congestive heart failure and pulmonary edema. 

Fluid balance In two patients undergoing transurethral resection, the bladder was irrigated with large volumes of mannitol 5%, which was absorbed and caused pulmonary edema and severe hyponatremia (serum sodium 99 and 97 mmol/1) [63 ]. Hypertonic saline increased the serum sodium concentration and plasma volume expansion corrected hypotension one patient also required positive-pressure ventilation and intravenous noradrenaline. Both recovered completely. 

Wang JH, He Q, Liu YL, Hahn RG. Pulmonary edema in the transurethral resection syndrome induced with mannitol 5%. Acta Anaesthesiol Scand 2009 53(8) 1094-6. 

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