Gastrointestinal bleeding in children
Introduction
Introduction to gastrointestinal bleeding in children Pediatric gastrointestinal bleeding can occur at any age, manifested as hematemesis, blood in the stool, or both. The cause of bleeding is complicated. In addition to the disease of the digestive tract itself, it may also be a local manifestation of systemic diseases. The bleeding site may be upper digestion. The road may also be the lower digestive tract. Upper gastrointestinal bleeding refers to the digestive tract above the Treitz ligament, such as esophagus, stomach, duodenum or pancreas, bile and other diseases; lower gastrointestinal bleeding refers to the digestive tract below the ligamentous ligament Such as small intestine, colon, rectum, anal bleeding. Children have poor tolerance to blood loss, clinical symptoms vary, some have large blood loss, fast speed, and can cause fatal hemorrhagic shock, while others have no obvious clinical symptoms, only manifested as fecal occult blood positive. Repeated small amount of bleeding, long-term can lead to anemia in children, must be timely to make the correct diagnosis and treatment. Although the current diagnostic methods have been greatly improved, the understanding of the pathophysiology of hypovolemic shock has been greatly improved. However, the diagnosis and treatment of gastrointestinal bleeding in children still needs further study. Pediatric gastrointestinal bleeding is not uncommon in clinical practice. In terms of body weight and circulating blood volume, the risk of bleeding in children is greater than that in adults. Therefore, it is important to quickly determine the cause, location and timely treatment of bleeding. basic knowledge The proportion of children: the incidence of this disease in young children is less, generally between 0.001% and 0.003%. Susceptible people: children Mode of infection: non-infectious Complications: anemia, shock, children with hypochloremic azotemia syndrome
Cause
Causes of gastrointestinal bleeding in children
(1) Causes of the disease
1. Local lesions of the gastrointestinal duct
The causes of bleeding common in different age groups are different:
(1) Newborn:
1 Upper digestive tract: swallowing maternal blood, stress ulcer, neonatal natural hemorrhage, milk intolerance, etc.
2 lower digestive tract: necrotizing enterocolitis, intestinal duplication, intussusception, congenital megacolon.
(2) Infants:
1 upper digestive tract: swallowing maternal blood, reflux esophagitis, stress ulcer, gastritis, hemorrhagic disease, Mallory-Weiss syndrome.
2 lower digestive tract: necrotizing enterocolitis, bacterial enteritis, intestinal obstruction affecting blood transport such as intussusception, intestinal repeat deformity.
(3) Children:
1 upper digestive tract: bacterial gastroenteritis, ulcer disease / gastritis, reflux esophagitis, Mallory-Weiss syndrome.
2 lower digestive tract: anal fissure is the most common; intussusception, inflammatory bowel disease, vascular malformation, intestinal vascular insufficiency, allergic purpura, polyps, parasitic diseases are not uncommon.
(4) Youth:
1 upper digestive tract: ulcer disease, inflammation, gastric esophageal varices, reflux esophagitis, Mallory-Weiss syndrome, biliary bleeding, pancreatitis.
2 lower digestive tract: bacterial enteritis, inflammatory bowel disease, polyps, sputum.
2. Systemic diseases
Gastrointestinal hemorrhage is a local manifestation of systemic diseases, blood system diseases such as leukemia, hemophilia, pernicious anemia, primary thrombocytopenic purpura, etc., in addition to systemic skin, subcutaneous tissue, joints, mucosal hemorrhage, may be accompanied Gastrointestinal and urinary bleeding, bone marrow, platelet count, peripheral blood and bleeding clotting time, blood clot contraction time can be confirmed.
(two) pathogenesis
Mucus damage
Various causes of digestive tract mucosal inflammation, erosion, ulcers can be due to congestion and edema, red blood cells exudation or ulcers eroding blood vessels and bleeding, such as severe infection, shock, extensive burns, etc. can occur stress response, resulting in gastric mucosa Blood, tissue energy metabolism abnormalities or decreased gastric mucosal epithelial cell turnover, leading to gastric mucosal erosion or ulceration and bleeding; digestive tract endoscopy, hard stool, etc., can damage the mucosa and bleeding.
2. Digestive tract circulatory disorder
Intestinal circulation reflux is blocked, so that the intestinal wall vein is obviously congested and ruptured, resulting in gastrointestinal bleeding, such as esophageal hiatus hernia, intussusception.
3. Increased capillary permeability
Infection poisoning, hypoxia, etc. can cause capillary permeability changes leading to mucosal oozing, capillary lesions such as allergic purpura, vitamin C deficiency, hereditary telangiectasia can also cause bleeding.
4. Bleeding coagulopathy
Lack of coagulation factors, thrombocytopenia or dysfunction can cause gastrointestinal bleeding, such as hemophilia, vitamin K deficiency.
Prevention
Pediatric gastrointestinal bleeding prevention
Prevention of local lesions of the gastrointestinal tract, such as esophageal varices, esophagitis, gastroduodenal ulcer, acute hemorrhagic necrotizing enterocolitis. Prevent infectious diseases such as sepsis, enteritis, and bacillary dysentery. Prevents vitamin K deficiency, gastrointestinal bleeding caused by allergic purpura.
Complication
Pediatric gastrointestinal bleeding complications Complications, anemia, hypoxic azotemia syndrome
Frequent small amount of bleeding can lead to anemia, large amount of bleeding, rapid, can cause hemorrhagic shock, and can be complicated by azotemia.
Symptom
Pediatric gastrointestinal bleeding symptoms Common symptoms fatigue, pale, dizziness, heart discharge, black stool, repeated vomiting, loss of appetite, nausea, circulatory failure, abdominal pain
The symptoms of gastrointestinal bleeding are related to the nature, location, blood loss, speed, and general condition of the patient before hemorrhage.
1. Hematemesis, melena and blood in the stool
Hematemesis represents bleeding above the pylorus. The color of hematemesis depends on whether the blood passes through the acidic gastric juice. If the amount of bleeding is large, the bleeding rate is fast, and the blood stays in the stomach for a short time. If the esophageal varices bleed, the hematemesis is dark red or bright red. Color, on the contrary, due to the formation of methemoglobin by blood acid, it is brown or brown, vomiting is often accompanied by black stools, black can be no hematemesis.
Black means that the bleeding comes from the upper digestive tract or the small intestine. The color of the stool is black, the tar is like, the color of the black stool is affected by the length of time the blood stays in the intestine. When the amount of bleeding is large, the bleeding speed is faster, the peristalsis is hyperthyroidism, and the feces can be presented. Dark red or even bright red, like the lower gastrointestinal bleeding; on the contrary, empty, ileal bleeding, such as a small amount of bleeding, long stay in the intestine, can also be expressed as black stool.
Blood in the stool means that the stool is bright red or deep reddish brown. The bleeding site is mostly located in the colon. However, when there is a lot of bleeding in the upper digestive tract, the blood will have a laxative effect, which will shorten the excretion time and make the stool bright red.
The stool trait is also affected by the amount of bleeding, the rate of bleeding, the amount of bleeding is large, the bleeding rate is fast, the stool is thin, the amount of bleeding is small, and the bleeding is slow, the stool is formed.
2. Other performance
Other clinical manifestations vary depending on the amount of bleeding, bleeding site and bleeding rate, small amount of bleeding, short bleeding time can be asymptomatic; long bleeding time can have chronic blood loss anemia, such as pale, fatigue, dizziness, appetite Lack of vibration, etc.; and a large amount of bleeding in the short term can cause hypovolemic shock, as follows:
(1) Peripheral circulatory disorders: a large amount of bleeding in a short period of time, can cause rapid reduction of circulating blood volume, insufficient blood flow to the veins, and reduced blood output, showing dizziness, fatigue, palpitations, sweating, dry mouth, pale skin, and dampness Wait.
(2) fever: the mechanism of fever is not clear, may be due to blood in the intestinal lumen, absorption of hemoglobin decomposition products, blood volume reduction, peripheral circulatory failure and other factors affecting the body temperature regulation of the fever.
(3) Nitrogenemia: After massive hemorrhage of the digestive tract, blood urea nitrogen is often elevated, first of all, intestinal azotemia occurs. Hemoglobin is decomposed and absorbed in the intestine after gastrointestinal bleeding. Urea nitrogen increased, intestinal azotemia appeared early, peaked at 24 to 48h, returned to normal after 3-4 days; when hemorrhage caused peripheral circulatory failure, renal blood flow and glomerular filtration rate decreased, resulting in Prerenal azotemia, rapid recovery to normal after shock correction; shock caused by tubular necrosis, can cause renal azotemia, even if shock correction, urea nitrogen does not decline.
Examine
Pediatric gastrointestinal bleeding check
The following checks should be made:
1. Hematological examination: blood routine, platelets, clotting time, thrombin and prothrombin time, liver function tests.
2. Regular stool examination, occult blood test and easy culture.
3. Bone marrow examination.
4. Swallowing method: The position of upper gastrointestinal bleeding can be roughly judged by using a thick white silk thread, about 2m long, and a small sugar ball is tied at one end, so that the child swallows and the other end is fixed on the cheek with tape. Department, with gastrointestinal motility, the white line is gradually released to the duodenum, after 24h, the line is gently pulled out, so as not to hurt the mucosa of the digestive tract, causing illusion, normal, white-yellow, such as intragastric bleeding White-red-yellow, duodenal hemorrhage is white-yellow-red, and the bleeding site is judged according to the staining of the line. It is necessary to cooperate with the child for this examination, otherwise it will be difficult to succeed in the line.
5. X-ray barium meal and barium enema examination: general requirements are in the condition of stable disease, blood pressure recovery, heart function improvement, but suspected esophageal varices bleeding, can be diagnosed during bleeding, swallowing examination, meal and air Double contrast, help to check the stomach, duodenum and small bowel diseases, such as peptic ulcer, tumor, intestinal stenosis, etc., double enema of barium enema or air on the rectum, sigmoid polyps, ulcerative colitis, tumor, intussusception Can make a diagnosis, and can observe the position of the colon to help diagnose intestinal malrotation.
6. Endoscopy: such as esophagoscopy, fiber stomach, duodenoscopy, fiber small intestine and colonoscopy, you can directly observe the location, cause and scope of the lesion, while taking photos, video, biopsy and treatment.
(1) esophagus, stomach, duodenal endoscopy: the application of fiber endoscopy for upper gastrointestinal bleeding in the past 20 years, the reason, the accuracy rate is very high, up to 85% to 90%, the diagnosis rate of barium meal is less than 50% Therefore, the endoscopic method is currently used, and the upper gastrointestinal bleeding is examined within 12 to 48 hours. The positive detection rate is 2 times higher than that of bleeding or advanced endoscopy. In principle, if the child is stable, the diagnosis is not When it is determined that emergency surgery is needed, endoscopy should be performed as soon as possible to facilitate hemostasis in the operation. Although the natural hemostasis rate of upper gastrointestinal bleeding is >90%, if the diagnosis is made by endoscopy, reasonable treatment can be given at the same time. It can also guide the prevention of recurrent bleeding. According to statistics, endoscopy in emergency department is 4 times larger than selective endoscopy. Therefore, indications should be strictly controlled.
(2) fiber colonoscopy: lower gastrointestinal bleeding is mainly blood, with fiber colonoscopy than the barium enema accuracy is high, and its specificity, can simultaneously take biopsy of colon lesions, with electrocoagulation, laser , heat condense bleeding points to stop bleeding.
(3) Sigmoid colonoscopy: This kind of examination is a simple and easy method. If you consider the sigmoid colon lesion below the descending colon, you can use this method. Children should be under anesthesia. Larger children are required to cooperate and operate. It is necessary to gently push the colonoscope forward slowly to avoid penetrating the intestinal wall or other accidents.
7. Radionuclide scanning
(1) Meckel's diverticulum hemorrhage: scanning with radioactive 99mTc-pertechnetate, 99mTc is easily absorbed by the gastric mucosa and accumulates in the gastric mucosa to identify whether there is an ectopic gastric mucosa in the Meckel's diverticulum or intestinal duplication. The incidence of Meckel's diverticulum is 0.3% to 3.0%, most of which do not contain gastric mucosa. If there is more than 90% of Meckel's diverticulum in the Meckel's diverticulum, there is an ectopic gastric mucosa in the room, so use 99mTc. The rate of scan diagnosis is very high. For example, pentagastrim can increase the sensitivity of the patient before scanning. Simultaneous use of cimetidine can delay the clearance of 99mTc, which can also improve the accuracy of diagnosis. It can be completed in 1 hour, so it can be considered in the case of lower gastrointestinal bleeding.
(2) Scanning and positioning in acute bleeding: When the cause of small intestine hemorrhage, the location is unclear, the endoscope can not be detected, or the arteriovenous malformation and intermittent recurrent hemorrhage are suspected, scanning technique can be used when the bleeding speed is less than 0.1ml/ At the time of min, some people used intravenous injection of sulfuric acid colloid Tc, which can diagnose the bleeding site. The radioactive exposure is extremely low, and the damage is small, but it is shorter than the radionuclide T1/2. It disappears after about 2 minutes after entering the reticuloendothelial system, thus affecting its development. Reliability.
99mTc-pertechnetate red blood cell marker scanning method, the blood sample of the child should be labeled with radionuclide before the examination, and then the labeled red blood cells are injected into the child's vein, and the liver is cleared and quickly disappeared from the blood circulation, but at the bleeding site or 99mTc at the arteriovenous fistula continuously leaks from the blood vessels. The abdominal site can determine the bleeding site. The method is more complicated, and the rate of active bleeding is 0.5ml/min or >0.5ml/min. It can be sensitive and correctly mark the gastrointestinal bleeding. The position of the radionuclide T1/2 is longer, and the gastrointestinal system can scan for imaging within 24 hours.
Radionuclide-labeled red blood cell scanning technology can also be used for angiography, diagnosis of bleeding sites, high sensitivity, low risk, requiring bleeding rate above 0.5ml/min, sedative or anesthesia to the child during operation, transfemoral The cannula is up to the mesenteric artery system, and the red blood cells labeled with nuclide are injected. At the same time, the abdominal scan can show the fate of the nuclide, such as vascular injury and arteriovenous malformation, lower gastrointestinal bleeding, and radionuclide exudation can be observed. Or brush-like, the diagnostic accuracy rate can reach 40% to 80%, the incidence of comorbidities is nearly 2%, and can be treated by intubation, such as injection of vasopressin or embolization of abnormal blood vessels.
Diagnosis
Diagnosis and diagnosis of gastrointestinal bleeding in children
diagnosis
The diagnosis of gastrointestinal bleeding includes qualitative, localization, judgment of bleeding volume and bleeding speed.
Qualitative
(1) Determine whether the substance you see is blood: Take some medicines (sputum, medicinal carbon, licorice, etc.), food (strawberry, beet, spinach, watermelon, tomato, etc.) can be mistaken for blood in the stool or black feces. disease.
(2) Whether it is gastrointestinal bleeding: blood in the nasopharynx or in the mouth can also be mistaken for gastrointestinal bleeding, vaginal bleeding or hematuria is also mistaken for blood in the stool, should be carefully examined before the diagnosis.
2. Positioning
Gastrointestinal hemorrhage can be caused by the disease of the gastrointestinal tract itself, or it may be a local manifestation of systemic diseases. Therefore, firstly, the systemic disease should be excluded, and then the upper gastrointestinal or lower gastrointestinal bleeding should be identified. The identification method is as follows:
(1) Clinical diagnosis: diagnosis and differential diagnosis can be made according to medical history, clinical manifestations, and fecal characteristics.
1 upper gastrointestinal bleeding: there are many ulcer disease, hepatobiliary disease or hematemesis history; hemorrhage is characterized by hematemesis with upper abdominal pain, nausea, acid reflux; stool is mostly tar-like stool, no blood clots.
2 lower gastrointestinal bleeding: there are many lower abdominal pains, abnormal bowel movements or blood in the history of hemorrhage; bleeding is manifested as blood in the stool, no hematemesis, accompanied by middle and lower abdominal discomfort, stool is mostly bright red or dark red, stool is thin, when there is a large amount of blood clots.
(2) Auxiliary examination: In the case of active bleeding, the following examinations may be considered for identification.
1 Nasogastric tube gastric juice examination: If the gastric juice is bright red or coffee is mostly upper gastrointestinal bleeding, clear bile is mostly lower gastrointestinal bleeding.
2 blood urea nitrogen concentration and creatinine concentration ratio: no matter how much bleeding, upper gastrointestinal bleeding ratio is higher than the lower digestive tract, the use of this biochemical indicators can easily distinguish between upper and lower gastrointestinal bleeding.
3 emergency endoscopy: emergency endoscopy is to point out that within 48h after blood, its sensitivity and specificity are higher, is the preferred diagnostic method for upper gastrointestinal bleeding, more advocated within 24 to 48h of bleeding, this The method can not only quickly determine the location of bleeding, clear the cause of bleeding, but also endoscopic hemostatic treatment, such as endoscopic spraying of norepinephrine, Yunnan Baiyao, etc., should be supplemented with blood volume before emergency endoscopy, correcting shock ,fasting. For those who are anxious, sedatives may be used. When the blood in the stomach affects the peep, the blood may be sucked out or the body position may be changed to change the blood and the position of the blood clot. For adherent blood clots, perfusion can be perfused to facilitate exposure of the lesion, but it is not necessary to remove adhering blood clots to avoid induction of active bleeding.
4 radionuclide scanning: mainly suitable for the location diagnosis of acute gastrointestinal bleeding and the detection of chronic intermittent gastrointestinal bleeding, the principle is to reduce the scorpion ions into strontium ions, and the reduced sputum is firmly combined with the chain of hemoglobin. The red blood cells are marked during active bleeding, and the positive results are displayed in the scan. The advantages are high sensitivity, non-invasive, and repeatable examination. The imaging time can last for 36 hours. The disadvantage is that only blood can be detected. I don't know where the bleeding, the positive rate of qualitative and localization is not high, but it can be used as a primary screening test before selective intra-abdominal angiography to determine the preferred contrast artery, such as marked red blood cells in the gastroduodenum. Celiac angiography is preferred.
5 Selective intra-abdominal angiography: indications: endoscopic examination of no upper gastrointestinal bleeding or endoscopy can not be achieved lesions or chronic recurrent or occult upper gastrointestinal bleeding such as diverticulitis, vascular abnormalities, Dysplasia or dilatation, hemangioma, arteriovenous fistula, etc., the celiac artery and superior mesenteric artery can be simultaneously angiographically analyzed. As long as the amount of bleeding reaches 0.5ml/min, the bleeding site can be found. The diagnostic accuracy can reach 70%-95. %, its advantages: specificity, high sensitivity, and can be used as a treatment, such as perfusion of vasopressin or embolization by arterial intubation, the disadvantage is expensive, invasive examination, there are certain anti-indications (such as coagulation mechanism Incomplete) and complications (such as bleeding, embolism).
3. Massive bleeding
It refers to hematemesis or blood in the stool. In a short period of time, the amount of blood loss is 20% to 25% of the circulating blood volume. The symptoms of shock appear in the clinic and rescue measures are needed.
4. Prevent recurrence
After basic hemostasis, the positioning diagnosis should be grasped to prevent recurrence. The following methods are available:
(1) Endoscopy: In the case of active bleeding, the positive rate of endoscopic localization is not high due to blurred vision, but endoscopy is performed 24 to 48 hours after hemorrhage, the positive rate can reach 80% to 90%, and can be found Multiple lesions bleeding, in addition, some lesions can be treated under endoscopy, such as injection of sclerosing agents, ligation and clamping.
(2) X-ray barium meal and barium enema examination: generally advocate 10 to 14 days after the cessation of bleeding, the diagnosis rate is less than 50%, the shortcoming is that acute micro or superficial lesions such as superficial ulcer, erosive hemorrhagic gastritis can not be found Etc., can not carry out biopsy at the same time, the advantages are convenient, painless, easy to be accepted by children, the diagnostic value of some bleeding causes such as gastric mucus prolapse, esophageal hiatus hernia is better than endoscopy.
Differential diagnosis
1. Whether the substance seen in the clinic is a blood red substance may be a dyed food such as watermelon or tomato; black stool may be mixed with black medicine, except for careful examination and testing.
2. Whether gastrointestinal bleeding is a manifestation of systemic hemorrhagic disease should be comprehensive and detailed physical examination, test peripheral blood and stool routine, diagnosed as systemic bleeding disease, then given medical treatment.
3. Bleeding site: Esophagus, stomach, duodenal hemorrhage is upper gastrointestinal bleeding, can vomit blood or aspiration through the stomach tube, and can discharge tar-like stool from the rectum, the lower gastrointestinal bleeding originates from the distal intestine of the ligament of the ligament, All are discharged from the rectum, such as small intestine hemorrhage, depending on the amount and speed of bleeding, may be tar-like or tan, bleeding at the end of the ileum and right colon, mostly dark red, rectal or anal bleeding is bright red, not mixed with stool The stool is separated from the blood.
