Salicylate poisoning in children
Introduction
Introduction to children's salicylate poisoning Salicylates commonly used in clinical practice include aspirin (acetic acid, acetylsalicylic acid), compound aspirin, sodium salicylate, sodium salicylate mixture, methyl salicylate (winter oil) and Other barium salts, ointments, etc. containing salicylates are mostly caused by accidental or conscious use, and most children are mistakenly taken. Salicylates have a wide range of toxic effects and can involve multiple systems throughout the body, so the performance is extremely complicated when poisoned. basic knowledge The proportion of illness: 0.005% Susceptible people: children Mode of infection: non-infectious Complications: hematuria, proteinuria, uremia, jaundice, asthma
Cause
Pediatric salicylate poisoning etiology
(1) Causes of the disease
Salicylate poisoning is mostly caused by excessive use or long-term application. The external salicylic acid ointment or powder is damaged in the skin and can be absorbed by the skin. It has dehydration, liver and kidney function. Incomplete, patients with low prothrombinemia are more likely to develop serious toxic reactions. Salicylates can pass through the placental barrier, and pregnant women take too much, often causing fetal or neonatal poisoning.
Poisoning symptoms can occur in children taking 2 to 4 times the amount of aspirin or sodium salicylate. The minimum lethal dose of aspirin is 0.3-0.4 g/kg, and the minimum lethal dose of sodium salicylate is about 0.15 g/kg. The lethal dose of oral green oil in children is about 4ml.
(two) pathogenesis
After oral salicylate drugs, it is quickly absorbed from the stomach and upper part of the small intestine. After 2 hours, the plasma concentration reaches a peak. Salicylate is mainly excreted by the kidneys. After normal administration of renal function, it can be seen in the urine in a few minutes. At 24h, about half of the poisoning amount can be discharged; if the urine is alkaline (pH 7.5 or higher), the excretion is accelerated by 3 times, and the salicylate in the blood can be reduced by half in 6 hours.
The pathophysiological changes caused by poisoning mainly include the following aspects:
1. Respiratory alkalosis: High concentration of salicylate stimulates the respiratory center, and excessive exhalation occurs. As a result, a large amount of CO2 is excreted in exhalation, causing respiratory alkalosis (blood pH rise), which is more common in children over 5 years old. .
2. Metabolic acidosis: With the above-mentioned central pathophysiological changes, due to the presence of respiratory alkalosis, renal compensation occurs, resulting in a large discharge of potassium and sodium with urine; at the same time due to vomiting, loss of water, loss of sodium, and Salicylate inhibits dehydrogenase and aminotransferase, blocks the tricarboxylate cycle, causes carbohydrate metabolism disorder, and eventually causes blood ketones to rise, forming metabolic acidosis, especially in infancy, stage 2 pathology. The physiological process develops very fast, making acidosis the main manifestation.
3. Peripheral circulatory failure: The toxic dose of salicylate can directly act on vascular smooth muscle, dilate the surrounding blood vessels, lower blood pressure, and paralyze the vasomotor center, leading to peripheral circulatory failure.
4. Bleeding tends to reduce whole blood: Salicylate can inhibit the synthesis of prothrombin in the liver. Aspirin also affects platelet function, such as the formation of ATP, which are all factors that cause bleeding. Aspirin is a weakly acidic substance, which has a gastric mucosa. Stimulating effect, long-term internal administration can induce gastrointestinal ulcer disease and chronic bleeding, but also due to inhibition of bone marrow hematopoietic function, causing severe anemia, and even complete blood reduction.
5. Kidney damage: Salicylate poisoning can cause kidney damage, severe tubular necrosis can occur, leading to acute renal failure, long-term high-dose application can cause changes in renal papilla, tubular necrosis, renal degeneration and atrophy.
6. Hepatitis, encephalopathy and allergic reactions: Aspirin can cause hepatitis, encephalopathy and allergic reactions.
In acute poisoning, the pathophysiological changes are mainly based on 1, 2.
Prevention
Pediatric salicylate poisoning prevention
Strictly control the indications and correct dosage of the application of this class of drugs, do not abuse; such drugs in the family, must be properly collected to prevent children from mistaking.
Complication
Pediatric salicylate poisoning complications Complications, hematuria, proteinuria, uremia, jaundice, asthma
Hepatic and renal dysfunction can occur hematuria, proteinuria, uremia and jaundice; allergic to this product causes asthma, purpura and throat phlegm.
Symptom
Symptoms of children with salicylate poisoning Common symptoms Nausea complexion flushing dehydration high fever tinnitus proteinuria abdominal pain dizziness jaundice throat
Symptoms are nausea, vomiting, abdominal pain, headache, dizziness, lethargy, deep breathing, tinnitus, deafness and visual impairment. It begins to look flushed. Afterwards, the skin is pale, the lips are cyanotic, the body temperature is lower than normal, and the sick child may have sweat and high fever. , dehydration, respiratory alkalosis or metabolic acidosis and other related symptoms, and may appear hematuria, proteinuria, uremia, etc.; or increase in transaminase and jaundice; or nosebleeds, retinal hemorrhage, hematemesis, bloody stools and other parts of the body Bleeding, even cerebrospinal fluid is also yellow, because salicylate can quickly pass through the placenta and the concentration in neonatal plasma is higher than that of pregnant women. Therefore, pregnant women taking aspirin can cause neonatal bleeding, severe poisoning and can occur. Hemorrhoids, hallucinations, insanity, muscle tremors, even convulsions, coma, shock, pulmonary edema and respiratory failure. Children who are allergic to this product can cause asthma, hemoptysis, hematemesis, rash, epidermal necrosis, purpura due to small amount of aspirin. Edema, or glottic edema and throat cramps.
Examine
Pediatric salicylate poisoning test
1. Qualitative test of ferric chloride: Put the gastric eluate or urine in a test tube and boil, add acid after cooling, then add a few drops of 5% to 10% ferric chloride solution, and the purple color turns purple. There is salicylate.
2. Detection of salicylate levels in the blood: After taking salicylate for 30 minutes, the presence of the salicylate can be determined; up to the peak of 6h, the toxicity standard: mild poisoning is 45 ~ 70mg / dl; moderate poisoning is 70100mg/dl, severe poisoning is 100130mg/dl or more.
3. Blood biochemical examination: As the transaminase increases, it can be seen that the CO2 binding force is greatly reduced, the CO2 partial pressure and pH value are lowered, and the blood sugar is decreased (it may be transiently increased).
The urine volume and pH of all poisoned children should be measured once every hour. During the treatment, blood pH, blood sugar, potassium and other electrolytes, renal function, prothrombin, etc. must be monitored. Chronic salicylic acid poisoning should pay attention to liver function, bilirubin The level of hormone and the original thrombin were abnormal.
Combined with clinical options X-ray, B-ultrasound, electrocardiogram, brain CT, EEG and other examinations.
Diagnosis
Diagnosis and identification of children with salicylate poisoning
According to the medical history, clinical manifestations and related examinations can be confirmed.
Different from other drug poisoning, respiratory alkalosis and metabolic acidosis exist simultaneously in this type of drug poisoning, but which disorder is often different for each sick child, and can be transformed before and after a sick child. Therefore, the pathological physiology can be different in each period. The most accurate method is to check the blood pH value and some other data to help the diagnosis. The items listed in Table 1 can be used for reference. The application must be fully considered and conclusions made.
