Neodymium magnet ingestion poses an emergency, but treatment delay has unknown effects. We evaluated this and other factors’ effects on outcomes at our institution.
Early presentation and gastric location indicate endoscopy, but symptoms or lack of movement on serial X-rays indicate surgery; free air or obstruction indicate emergent surgery. Moving magnets can be “assisted” with polyethylene glycol, which may facilitate colonoscopy if warranted.
We found much variability but little relationship between esophagogastroduodenoscopy (EGD) timing and success.
Early presenters (≤10h) avoided invasive procedures and complications. All complications occurred in patients with later intervention. Early hospital presentation may be associated with better outcomes.
Introduction
Pediatric ingestion of foreign objects is a common occurrence. In 2016, there were more than 80,000 reported cases in the United States, primarily involving children under 5 years.1
Ingestion of small blunt objects typically resolves without medical intervention. However, cases involving ingestion of magnets have been shown to present increased risk of life-threatening morbidity,2-5 particularly if more than one is ingested.3 Despite regulatory efforts, the incidence of emergency department visits for magnet ingestion in pediatric patients increased 8.5-fold from 2002 to 2011, even with evidence of under-reporting.3
Rare earth metal (neodymium) magnets are common in household objects, including toys. These magnets are often small, but considerably stronger than common “refrigerator magnets,” increasing both the risk of attraction across multiple tissue layers and the objects’ resistance to being separated by peristaltic activity,4 eventually leading to pressure necrosis and perforation. Other clinical sequelae include ulcer, bleeding, bowel obstruction, fistula, volvulus, sepsis, and bowel resection.2
While published guidelines for magnet-ingestion management exist,5 the relationship of elapsed ingestion-treatment time with success of EGD versus requirement for laparotomy has received less attention. We aimed to assess whether delay may affect the success of this technique.
Materials and Methods
After approval by the Human Research Review Committee at the University of New Mexico Health Sciences Center, we conducted a retrospective chart review of all endoscopies and exploratory laparotomies for foreign body ingestions at our institution from January 2012 to October 2020. We reviewed all pediatric cases involving ingested magnets to assess any association between the ingestion-intervention interval and morbidity. We excluded cases involving patients over age 18, foreign bodies other than magnets, and ingestions of a single magnet without additional ferromagnetic objects.
Results
We identified 22 cases meeting our criteria. Removal procedures included 10 EGDs, seven colonoscopies, and nine diagnostic laparoscopies and exploratory laparotomies; four patients underwent more than one procedure.
The average observed ingestion-procedure intervals for specific outcomes are:
- Successful removal with EGD — 6.5 hours
- Magnets beyond EGD reach — 5.5 hours
- Colonoscopy — 3 days
- Diagnostic laparoscopy/exploratory laparotomy — 6 days
Adverse outcomes we observed included: esophageal perforation; ileocecectomy with ileal appendiceal fistula; multiple bowel perforations; partial thickness necrosis on small bowel; and partial cecectomy with appendectomy.
Discussion
Time interval between ingestion and successful endoscopic removal of magnets varied significantly. The promptness of EGD did not predictably affect its success. When EGD was attempted, average ingestion-procedure intervals were shorter for cases in which the magnets had already passed the stomach and duodenum (5.5 hours) than for those in which EGD successfully retrieved the magnets (6.5 hours), although this difference was not statistically significant. Possible reasons for this paradox are inaccurate reporting of the time the magnets were swallowed and variability in gastric motility and emptying from patient to patient. The timing of magnets exiting the stomach appeared to be highly variable; in one patient, this occurred within 3 hours.
Every unsuccessful EGD case in our sample had good outcomes. Patients were followed with serial X-rays and treated with laxatives, either passing the magnets in stool (though we only observed this in patients over age 10) or undergoing removal with colonoscopy. These good outcomes despite EGD retrieval failure represent a selection effect; EGD was only considered with early presentation.
Regardless of EGD success, all patients who presented early (within ~10 hours) avoided invasive procedures such as exploratory laparotomy and had no complications. This supports the conclusion that prompt hospital care is associated with better outcomes and decreased morbidity.4 All serious morbidity in our series occurred in patients with interventions occurring 20 hours to one month after ingestion.
One caveat is the reliability of self-reporting by caregivers. Ingestion time may be estimated, such as when the event was not directly observed, or there was a delay in seeking hospital care. However, the distinction between short- and long-interval cases is likely reliable. Another caveat is that our experience is limited; early presentation can only reduce morbidity and/or the need for surgical interventions; it cannot prevent them entirely.
If presentation is early and X-ray shows all magnets in the stomach, endoscopic removal is preferred. If magnets have passed the stomach and are clustered together, a short observation period with laxative administration is warranted. Magnets moving on serial X-rays can be followed until they pass.
Colonoscopy-preparation solution (e.g., polyethylene glycol) may help magnets move and can facilitate later colonoscopy if they stop distally. If magnets stop moving or any symptoms develop, immediate intervention (colonoscopy or surgery) is necessary. It is important to note that symptoms may be subtle but include pain, fever, and vomiting.5 If X-ray shows free air or obstruction, surgery is needed emergently.
Given the severity of possible outcomes with delayed presentation and apparent benefits of prompt presentation, we recommend counseling caregivers to seek medical care urgently when magnet ingestion is known or suspected.
Conflict of Interest Statement: The authors have no relevant financial or non-financial interests to disclose.
References
- Wood ML, Potnuru PP, Nair S. Inpatient pediatric foreign body ingestion: national estimates and resource utilization. Journal of Pediatric Gastroenterology and Nutrition 2021; 73:37-41.
- Middelberg LK, Leonard JC, Shi J, et al. High-powered magnet exposures in children: a multi-center cohort study. Pediatrics 2022; 149(3):e2021054543
- Abbas MI, Oliva-Hemker M, Choi J, Lustik M, Gilger MA, Noel RA, Schwarz K, Nylund CM. Magnet ingestions in children presenting to US emergency departments, 2002-2011. Journal of Pediatric Gastroenterology and Nutrition 2013; 57:18-22.
- De Roo AC, Thompson MC, Chounthirath T, Xiang H, Cowles NA, Shmuylovskaya L, Smith GA. Rare-earth magnet ingestion-related injuries among children, 2000-2012. Clinical Pediatrics 2013; 52:1006-13.
- Altokhais T. Magnet ingestion in children: management guidelines and prevention. Frontiers in Pediatrics 2021; 9:727988.