Accidentally swallowing a non-edible object, including metal, is a common occurrence, especially for young children who often explore by putting items in their mouths. While many such ingestions are benign, understanding the potential journey and risks associated with swallowed metal is important.
The Initial Path
When a small, smooth metal object is swallowed, it typically enters the esophagus, the muscular tube connecting the throat to the stomach. From there, it moves into the stomach, where digestive acids begin to act on it, although metal is generally not digested. The object then proceeds into the small intestine. The natural muscular contractions of the digestive system, known as peristalsis, usually propel the object through the intestines. Most small, blunt, and non-toxic foreign objects, including many metal items, pass through the entire gastrointestinal tract without complications; approximately 80% pass without medical intervention. However, certain anatomical narrowings within the digestive tract, such as in the esophagus or near the ileocecal valve, can sometimes cause objects to become temporarily lodged.
When Problems Arise
Despite the common uneventful passage, specific types of metal objects can pose significant risks. Sharp metal objects, like needles, pins, or broken fragments, are particularly dangerous because they can pierce the delicate lining of the digestive tract. This perforation can lead to serious conditions such as mediastinitis if the esophagus is punctured, or peritonitis if the abdominal cavity is affected, both of which are life-threatening infections.
Large metal objects, such as coins or sizable pieces of jewelry, primarily risk causing an obstruction. Objects larger than about 2.5 centimeters (1 inch) in diameter or 5 centimeters in length are less likely to pass spontaneously. If such an object becomes stuck, it can block the passage of food and fluids, leading to pain and potential tissue damage.
Button batteries, commonly found in small electronics, present a unique and urgent danger. If a button battery becomes lodged in the esophagus, it can cause severe chemical burns and tissue damage within as little as two hours due to an electrical current and the release of alkaline chemicals. This damage can rapidly progress to perforation of the esophagus, even if the battery is “dead.”
Swallowing multiple magnets, or a magnet along with another metal object, creates a particularly hazardous situation. The magnetic attraction can cause different parts of the bowel to pinch together, even across intestinal loops. This pinching can cut off blood supply to the trapped tissue, leading to pressure necrosis, the formation of abnormal connections called fistulas, or holes in the intestines.
In rare instances, ingesting certain toxic metals, such as lead or mercury, can lead to systemic poisoning. Heavy metals can interfere with cellular processes and accumulate in the body, damaging vital organs like the brain, kidneys, and liver, potentially causing a range of severe symptoms.
Recognizing Serious Symptoms
Observing specific warning signs is crucial for determining if a swallowed metal object is causing a problem. Difficulty swallowing, medically termed dysphagia, or pain during swallowing (odynophagia) can indicate that an object is lodged in the esophagus. Individuals may also report a persistent sensation of something being stuck in their throat or chest.
Abdominal pain or cramping, particularly if severe or persistent, can signal an issue further down in the digestive tract. Vomiting, especially if it contains blood (hematemesis), or gagging and retching, are serious indicators. Changes in bowel habits, such as the inability to pass stool, or the presence of rectal bleeding or black, tarry stools, suggest potential damage or obstruction within the intestines.
A fever can be a sign of infection or inflammation resulting from the swallowed object. If the object has inadvertently entered or is pressing on the airway, symptoms like choking, wheezing, difficulty breathing, or excessive drooling may occur. In children, irritability, refusing to eat, or unexplained drooling can be subtle but important signs that a foreign object is causing distress.
Medical Intervention
When a metal object is swallowed, medical professionals begin with an assessment, often using imaging techniques like X-rays to locate the object and determine its size and position. CT or MRI scans may also be used to identify complications or if the object is not visible on X-ray.
For small, blunt, non-toxic objects that are not causing symptoms, watchful waiting may be appropriate. Medical providers might advise monitoring the individual’s stool to confirm the object’s passage, as this conservative approach is suitable when natural passage is expected.
If the object poses a significant risk or causes symptoms, endoscopic removal is often the primary treatment. This minimally invasive procedure involves inserting an endoscope—a long, flexible tube with a camera and specialized instruments—through the mouth to visualize and retrieve the object. Endoscopic retrieval is commonly used for high-risk items such as button batteries, magnets, sharp objects, or large objects.
Surgical intervention is typically reserved for complicated cases where endoscopy is not possible or has failed, or when severe complications like perforation or intractable obstruction have occurred. Less than 1% of foreign body ingestions require surgery. The specific medical approach depends on the object’s type, size, location, and the presence and severity of any symptoms.