Tracheal Aspiration of Capsule Endoscopes: Completing a Cases Compilation

Abstract

We read with great interest the report and compilation of cases of capsule endoscope (CE) aspiration by Lucendo et al. [1]. We would like to add two more cases to complete the compilation of reported cases. We had described the case of a 76-year-old man who underwent an inpatient CE with PillCam" SB1 and experienced a short-lived (15 s), by and large asymptomatic aspiration [2]. Depriest et al. [3] reported the case of a 90-year-old man, with multiple comorbidities, who aspirated the CE into the left main bronchus and eventually underwent flexible bronchoscopy for retrieval of the device with a Roth net. As in the Lucendo et al. case, CE aspiration in the aforementioned cases precipitated the cough reflex, which (albeit weak) in our case, led to dislodgment of the capsule and uneventful completion of the test. Lucendo et al. [1] point out that in case of CE aspiration, the relative size of the CE (11 9 26 mm) compared with the average antero-posterior and transverse diameter of an adult trachea (16 and 14 mm, respectively), allows enough space for adequate patient oxygenation; therefore, no fatalities have been described until now. Although four companies are competing in the market for the production of capsule endoscopy systems, the PillCam"SB remains the most widely used capsule worldwide for the study of the small bowel [4]. The sum total of CE aspirations reports are with PillCam"SB; interestingly, EndoCapsule" (Olympus Medical Systems, Tokyo Japan) is of exactly the same dimensions, while Intromedic Co. Ltd., Seoul, Korea produces the smaller and lighter MiroCam" (11 9 24 mm, 3.4 g), while Jinshan Science and Technology Company, Chongqing, China provides the bigger and heavier OMOM"CE. It is tempting to hypothesize that, although the possibility of a rare complication is more likely with the more commonly used system, the CE size might play a role in the response. Since a number of CE aspiration cases present with no or very weak cough (as in our case), we believe that patients with increased aspiration risk should swallow the CE while connected with real-time viewers, available for each system at the point of capsule ingestion. However, despite the theoretical advantage of a smaller and lighter shape, the image transmission mode of the Mirocam"CE does not generally allow acquisition of useful images of the oropharynx/upper esophagus during the ingestion phase. Finally, we would like once more to note that a potential serious complication as this should be included in the consent form for the procedure [2] and that for certain patient cohorts (elderly, patients with dysphagia or multiple co-morbidities) CE administration should take place in a controlled environment with oxygen and resuscitation facilities at close proximity. In our practice, we always confirm CE position with a real-time viewer in the immediate post-ingestion period, and prior to allowing patient discharge. Moreover, if endoscopy capsule placement is considered necessary we prefer to use for this the AdvanCE" delivery device and not the Roth net as we found that the floppiness of the last and its pointy end prevent a comfortable esophageal intubation. A. Koulaouzidis (&) ! S. Douglas ! J. N. Plevris Endoscopy Unit, Centre for Liver & Digestive Diseases, The Royal Infirmary of Edinburgh, 51 Little France Crescent, Edinburgh EH16 4SA, UK e-mail: akoulaouzidis@hotmail.com