Assessment of laryngeal tube placement on post mortem computed tomography scans

Background: Laryngeal tubes (LT) as opposed to endotracheal tubes (ET) appear to be relatively rare in the medico-legal caseload of the Institute of Forensic Medicine of the University of Zürich(IFMZ). They contain possible relevance for medicolegal casework: they significantly differ from ET in that a LT's lower end correctly resides in the upper esophagus, and despite being designed to specifically facilitate fast and easy correct placement particularly in emergency situations they might not always live up to expectations. This study documents the computed tomography (CT) post mortem appearance of an LT as well as three cases with such a device in place. Method and material: One LT device and all three bodies admitted to the IFMZ so far that were found to contain an LT in situ underwent CT scanning. Results: Of three cases, one was found to contain an LT that was both in correct position and patent. A second case contained an LT that was blocked by food. In a third case the LT was positioned too low relative to anatomical landmarks. Only the case with correctly placed and patent LT featured an inflated and ventilated appearance of the lungs. Conclusions: LT position and patency should be examined and reported not just by radiologists but also by forensic pathologists. No conventional autopsy technique has been published so far to exhibit the relevant details in relation to LT usage.