Why does aspirin toxicity cause fever

Excretion of salicylates increases when urine pH increases. With acute overdose, early symptoms include nausea, vomiting, tinnitus, and hyperventilation. Later symptoms include hyperactivity, fever, confusion, and seizures. Rhabdomyolysis Rhabdomyolysis Rhabdomyolysis is a clinical syndrome involving the breakdown of skeletal muscle tissue.

Symptoms and signs include muscle weakness, myalgias, and reddish-brown urine, although this triad is Hyperactivity may quickly turn to lethargy; hyperventilation with respiratory alkalosis progresses to hypoventilation with mixed respiratory and metabolic acidosis and respiratory failure.

With chronic overdose, symptoms and signs tend to be nonspecific, vary greatly, and may suggest sepsis. They include subtle confusion, changes in mental status, fever, hypoxia, noncardiogenic pulmonary edema, dehydration, lactic acidosis, and hypotension. Other findings compatible with sepsis Sepsis and Septic Shock Sepsis is a clinical syndrome of life-threatening organ dysfunction caused by a dysregulated response to infection. In septic shock, there is critical reduction in tissue perfusion; acute failure If poisoning is suspected, serum salicylate level drawn at least a few hours after ingestion , urine pH, ABGs, serum electrolytes, serum creatinine, plasma glucose, and blood urea nitrogen BUN are measured.

If rhabdomyolysis Rhabdomyolysis Rhabdomyolysis is a clinical syndrome involving the breakdown of skeletal muscle tissue. Serum levels are helpful in confirming the diagnosis and may help guide therapy, but levels may be misleading and should be clinically correlated. Eventually, usually as salicylate levels decrease, poorly compensated or uncompensated metabolic acidosis is the primary finding.

If respiratory failure occurs, ABGs suggest combined metabolic and respiratory acidosis, and chest x-ray shows diffuse pulmonary infiltrates. Plasma glucose levels may be normal, low, or high. Serial salicylate levels help determine whether absorption is continuing; ABGs and serum electrolytes should always be determined simultaneously. Increased serum CK and urine myoglobin levels suggest rhabdomyolysis.

Unless contraindicated eg, by altered mental status , activated charcoal is given as soon as possible and, if bowel sounds are present, may be repeated every 4 hours until charcoal appears in the stool.

Alkaline diuresis is indicated for patients with any symptoms of poisoning and should not be delayed until salicylate levels are determined. This intervention is usually safe and exponentially increases salicylate excretion. Because hypokalemia Hypokalemia Hypokalemia is serum potassium concentration 3. The most common cause is Serum potassium is monitored. Because fluid overload can result in pulmonary edema Pulmonary Edema Pulmonary edema is acute, severe left ventricular failure with pulmonary venous hypertension and alveolar flooding.

Findings are severe dyspnea, diaphoresis, wheezing, and sometimes blood-tinged Fever can be treated with physical measures such as external cooling Cooling techniques Heatstroke is hyperthermia accompanied by a systemic inflammatory response causing multiple organ dysfunction and often death. As liver enzymes become saturated in overdoses, metabolism converts to zero-order kinetics fixed A small amount is excreted unchanged via kidneys.

Renal excretion is more important in overdose situations when liver enzymes are saturated Mechanism of Toxicity: In adults, aspirin toxicity initially causes a respiratory alkalosis because of its direct stimulatory effects on respiratory centers in the medulla.

It is unclear whether or not this is observable in children. This occurs because salicylate interrupts aerobic respiration by uncoupling oxidative phosphorylation and interfering with the krebs cycle.

This results in the anaerobic production of lactate. Instead plasma concentration as well as clinical judgment should be used to make decisions. Poison Control can be a fantastic resource for helping you to manage these patients. Click on the link below or call the 1 number for help. Give IVF to replace fluid losses caused by tachypnea, vomiting, fever.

For moderate intoxications, give IV sodium bicarbonate to alkalinize the urine and promote salicylate excretion by trapping the salicylate in its ionized form. For severe poisoning consider emergency hemodialysis to remove the salicylate more quickly and restore acid-base balance and fluid status.

Definition The first sign of salicylate toxicity is often hyperventilation and respiratory alkalosis due to medullary stimulation.