What Is Gastric Lavage?

Gastric lavage refers to pouring a certain amount of liquid into the gastric cavity, mixing the gastric contents and then drawing it out, and so on many times. The purpose is to remove unabsorbed poison in the stomach or clean the gastric cavity, and is used clinically for gastric surgery and preparation before examination. For acute poisoning, such as swallowing organic phosphorus, inorganic phosphorus, alkaloids, barbiturates and other drugs in a short time, gastric lavage is an important rescue measure.

Basic Information

English name

gastriclavage

Visiting department

Emergency Department

Common symptoms

Gastric lavage

Contagious

no

Gastric lavage classification

Gastric lavage

Vomiting is an instinctual self-defense response of the body to eliminate stomach poisons. Gastric lavage with vomiting is simple and easy. It is an effective self-rescue for on-site rescue for patients with acute poisoning who are short of poisons and conscious (except for corrosive poisons, petroleum products, esophageal varices, upper gastrointestinal bleeding, etc.) And mutual rescue measures.

2. Gastric tube gastric lavage

It is to insert the gastric tube from the nasal cavity or the mouth, reach the stomach through the esophagus, suck the poison first, then inject gastric lavage fluid, and discharge the stomach contents to achieve the purpose of eliminating the poison. Patients with oral poisons should have gastric lavage as soon as possible when conditions permit, not limited by time. For those who take a large amount of poison within 4 to 6 hours, because of the good detoxification effect and relatively few complications, this gastric lavage method should be preferred.

Gastric lavage indications and contraindications

1. Oral intake of toxic substances

Those who ingest various toxic substances, such as pesticides, overdose, and food poisoning, should quickly wash the stomach as soon as possible in order to clear the poison.

2. Examination or preoperative preparation

Patients with pyloric obstruction accompanied by a large amount of gastric fluid retention need to be checked for barium meal or preparation before surgery. Those with acute gastric dilation who need to expel gastric contents and decompress should be placed in a catheter for suction and lavage.

3. For patients taking strong corrosives (such as strong acid and alkali), gastric lavage is contraindicated. Patients with esophageal varices and aortic aneurysms should be cautious.

Preparation before gastric lavage

Item equipment

(1) The most commonly used gastric lavage solution is warm boiling water at 37 ~ 40 ° C. Normal saline, 1: 5000 potassium permanganate solution, 2% sodium bicarbonate solution, etc. can also be used;

(2) One set of gastric lavage dish includes a thick stomach tube or funnel-type gastric lavator, 50ml or 100ml syringe, opener, tongue forceps, paraffin oil, gauze, treatment towel, rubber blanket;

(3) Other measuring cups, buckets, and inspection specimen bottles. Those who have the conditions prepare electric gastric lavators.

2. Patient cooperation

Patients should remove movable dentures, clean the mouth, and conscious patients should explain to them the purpose of gastric lavage and brief procedures for cooperation.

Gastric lavage procedure

Oral vomiting

Generally awake patients with better condition, let the patient take gastric lavage (1000 ~ 1500ml) orally, and stimulate the pharynx with tongue depressor to cause vomiting. This is repeated until the stomach contents are washed.

2. Gastric tube gastric lavage method

Gastric lavage can be divided into gastric tube method, gastric lavator method and electric gastric lavator method.

(1) The patient is lying close to the bed with his head tilted, and the blanket treatment towel is placed behind the neck and shoulders and submandibular chest.

(2) Built-in catheter and lavage into the stomach Gastric tube method Large-sized gastric tube for adults, urinary catheters for children, and generally nasal insertion. Specific procedure course: Bis gastric tube insertion method. After confirming that the catheter is in the stomach, you can inject gastric lavage fluid with a syringe, 300 ~ 500ml each time. Repeat this process until the poison is washed. Funnel gastric lavage method There is a funnel at the end of the gastric lavator. The middle section is equipped with a rubber ball. The front section is a gastric catheter. If you are unconscious, you can use an opener to open the mouth. Tongue forceps gently pull out the tongue. Place it in the stomach. Then increase the height of the gastric lavator funnel 30 40cm from the oral cavity, and then slowly inject gastric lavage fluid through the funnel, about 500ml once. When the liquid in the funnel is filled, lower the funnel to the stomach level and invert the funnel. The siphon effect can be used to drain the gastric fluid. If the drainage is not smooth, you can pinch the rubber ball to enhance the siphon outward drainage. Similarly, if the speed is too slow during perfusion, you can also pinch the ball to increase the perfusion speed. The above operation should be repeated many times to complete the cleaning. Electric gastric lavage machine method This gastric lavage machine is equipped with two large and measurable large glass bottles (one for gastric lavage and the other for collecting gastric fluid) and a positive and negative two-way motor. The gastric lavage fluid is infused into the stomach and reaches a predetermined amount (usually 500ml each time). The positive pressure is turned off and the negative pressure is used to suck the gastric fluid. Repeat this process many times until it is clean. The catheter inserted into the stomach should be a thicker gastric tube or other rubber tube, which needs to be inserted through the mouth.

(3) Extubation Any of the above methods should be repeated lavage, until the extracted liquid is clear and the gastric lavage liquid has the same color and brightness, and no odor (such as garlic poisoned by pesticides), you can consider stopping gastric lavage and removing the catheter. Generally, the amount of gastric lavage fluid needs to be 5000ml or even 10000ml. Before extubation, a cathartic agent such as 60% 50% magnesium sulfate or 250ml mannitol can be injected into the stomach to clear the poison that has entered the intestine through diarrhea. Because magnesium ions have a inhibitory effect on the central nervous system, they can make coma worse in coma patients, and mannitol has a cathartic effect and taste better than magnesium sulfate. Therefore, 20% mannitol is generally recommended for catharsis. After gastric lavage, clean the mouth with water or 0.9% sodium chloride solution repeatedly.

Gastric lavage precautions

1. Gastric lavage is mostly used for acute poisoning and requires the word "quick" because delays in time will increase the absorption of poisons and will threaten life. Therefore, we must strive for time, fight against every second, quickly prepare items, and immediately perform gastric lavage.

2. The general principle of gastric lavage time is to be as early as possible, and implemented as soon as possible. General principles Gastric lavage is most effective within 4 to 6 hours after taking the poison. However, some patients have more than 6 hours of consultation, and gastric lavage can still be considered. The following factors can keep the poison in the stomach for a long time: poor gastrointestinal function of the patient, so that the poison stays in the stomach for a long time; after the poison is absorbed Absorption; poison enters the stomach more; some poisons absorb slowly, such as the poison itself with a capsule shell and so on.

3. The catheter inserted into the stomach should be gentle and agile, and after confirming that the catheter has entered the stomach (the most reliable way to extract gastric juice), start lavage. Do not mistakenly insert the catheter into the respiratory tract for lavage. Severe cough, shortness of breath, or cyanosis struggling during catheterization suggest that the airway should be removed and reintubated quickly. Coma and vomiting at the time of coma and intubation are prone to aspiration pneumonia, and precautions should be taken.

4. Warm boiled water is the most commonly used and effective and safe. 2% sodium bicarbonate solution is often used for poisoning with organophosphorus pesticides, but it should not be used as trichlorfon, salicylate and strong acid poisoning; 1: 5000 high Potassium manganate solution has oxidative and detoxifying effects on alkaloids and muscarines, but it is prohibited in gastric lavage for parathion poisoning. Therefore, the choice of gastric lavage fluid should be considered according to different poisons, only water is the most extensive.

5. The amount of perfusion during gastric lavage should not be too much, generally 300 ~ 500ml should be suctioned each time. In particular, when applying positive pressure to the gastric lavage fluid with a motor, close observation should be performed. When 500ml is reached, the positive pressure is turned off and the suction is switched to negative pressure. The operator should not open the scene immediately after starting the machine to prevent excessive gastric perfusion caused by acute gastric distension or even Gastric perforation, too much perfusion can easily cause a large amount of poisons to enter the intestine, and the absorption of poisons increases. The use of electric gastric lavage machine should also add gastric lavage fluid to the bottle at any time to avoid sending a large amount of air into the stomach. For gastric ulcers with ulcer disease and throttle obstruction, the amount of lavage should be small and the pressure should be low to prevent perforation or bleeding.

6. If gastric lavage for strong corrosive poison will cause certain damage, perforation may be caused during intubation, gastric lavage is generally not suitable, and gastric perforation and tear are easily caused when a large amount of liquid enters. Convulsions may be induced in patients with convulsions during intubation. Intubation in coma patients is likely to cause aspiration pneumonia. Gastric lavage should be cautious. When gastric lavage must be performed, the patient should lie on his back with his head tilted to one side to prevent aspiration from aspiration. Patients with esophageal varices should not have gastric lavage.

7. Water Poisoning and Electrolyte Disturbance: Water poisoning occurs due to gastric lavage and various other reasons that cause too much water in the body to cause water balance imbalance. A lot of potassium ions and chloride ions are lost during gastric lavage, and excessive sugar input during dehydration, dehydration treatment and hormone application will make potassium loss more serious. Therefore, gastric lavage should pay attention to hypokalemia and hypochloric alkalosis.

8. Cardiopulmonary resuscitation should be performed for patients with respiratory arrest and cardiac arrest before gastric lavage. Vital signs should be checked before gastric lavage. If hypoxia or excessive secretion of the respiratory tract, sputum should be sucked to keep the airway open before gastric lavage. During the gastric lavage process, the patient's vital signs should be observed at any time. If the patient feels abdominal pain, bleeding lavage fluid, or shock, he should immediately stop gastric lavage.

9. After the first lavage, the extract should be taken and sent to the relevant laboratory to identify the toxic species and facilitate the treatment.