Postmortem computed tomography is an informative approach for prevention of sudden unexpected natural death in the elderly

Toshihiro Kaneko^1,2, Miyuki Hibi¹, Miki Ishibashi¹, Atsuhiro Nakatsuka^2,3, Yukinari Omori⁴, Ken Ishikura⁴, Tsuyoshi Hatada⁴, Taichi Takeda⁴, Yoshiyuki Takei^1,2, Kan Takeda³

¹Department of Patient Safety, ²Autopsy Imaging Center, ³Department of Radiology, ⁴Emergency Department, Mie University Hospital, Japan

Introduction: Less than 10% of unnatural death cases have been examined by autopsy in Japan. In particular, the causes of death in the elderly have not yet been actively investigated. Here, we evaluated the possible use of postmortem computed tomography (PMCT) to investigate the causes of sudden unexpected natural death (SUND) in the elderly.

Methods and subjects: Death cases confirmed within 24 hours since the onset of symptoms at the Emergency Department of Mie University Hospital were defined as sudden death cases. A total of 212 sudden death cases, including 175 SUND cases, that occurred in a 3-year period from September 2006 to August 2009 were investigated.

Results and discussion: The number of sudden death cases was highest in patients in their seventies (56 cases, 26%), followed by patients in their eighties and sixties. Sudden death occurred more in men than in women in their fifties to seventies, while it occurred more in women than in men over the age of 90. PMCT was performed in more than 80% of SUND cases regardless of age of the deceased. The causes in 26 cases (27.1%) were established by PMCT, many of which were hemorrhagic diseases. Signs of aortic aneurysm rupture were detected by PMCT in the thoracic and abdominal areas of 8 patients in their seventies and over, whereas signs were absent in the younger group. Also, more than 18% of sudden death cases in patients in their seventies and over were bathing-related sudden death (BRSD). BRSD was rarely caused by hemorrhagic diseases, suggesting that a drop in blood pressure caused by bathing is an important factor in BRSD.

Conclusion: PMCT is a method that is relatively acceptable by bereaved families. It is useful for establishing the causes of approximately 30% of the SUND cases examined. The PMCT findings suggested that early detection and treatment of thoracic and abdominal aortic aneurysms and preventive measurements of bathing-related drop in blood pressure are important for the prevention of SUND in the elderly.

Keywords: sudden unexpected natural death (SUND), postmortem computed tomography (PMCT), bathing-related sudden death (BRSD)