Aspiration of an M2A Capsule

A 64-year-old patient was referred to our hospital for further evaluation of anemia. Due to recent mechanical mitral valve replacement, the patient was receiving phenprocoumon for effective anticoagulation. He presented in a markedly impaired clinical condition (174 cm, 47 kg). Since previous upper gastrointestinal endoscopy and colonoscopy had not revealed any bleeding source, wireless small bowel capsule endoscopy was performed.

The patient was asked to swallow a standard M2A capsule (Given Imaging Ltd., Yoqneam, Israel) with water, in the presence of a physician. Initially, he made four efforts to swallow the capsule. Each time, the patient ended up gagging and subsequently spitting out the capsule. During the last attempt, transient aspiration was presumed clinically, due to recurrent coughing. After an interval of 2h, the patient swallowed the capsule without further complaints.

The next day, evaluation of the data showed that the patient had aspirated the capsule during the fourth attempt. Figure [1] shows the initial view of the trachea. The capsule then slid further into the right main bronchus, facing the orifices of the upper and lower lobe bronchi (Figure [2]). After about 2min of coughing, the patient had successfully removed the capsule from the bronchial system. An analysis of the images 2 hafter the last attempt at swallowing documented appropriate swallowing and subsequent adequate small-bowel visualization.

Figure 1 M2A capsule image of the trachea. The tracheal cartilage is easily identified.

Figure 2 View from the right main bronchus, facing the orifices of the upper and lower lobe bronchi (arrows).

Aspiration of the M2A capsule is a rare complication of wireless small-bowel endoscopy, which has not previously been described [1] [2]. However, it may be expected - particularly in patients who are in reduced general condition, with dehydration or myopathy - if coughing or dyspnea follow ingestion. If the patient does not produce the capsule in these conditions, further evaluation with chest radiography or endoscopy should be initiated.

References

• 1 Rösch T. Small-bowel endoscopy.  Endoscopy. 2002;  34 896-899
• 2 Ell C, Remke S, May A H . et al . The first prospective controlled trial comparing wireless capsule endoscopy with push enteroscopy in chronic gastrointestinal bleeding.  Endoscopy. 2002;  34 685-689