Lethal pulmonary thromboembolism: An autopsy-based study on a rare but legally relevant event

Context: Pulmonary thromboembolism (PTE) is the severe end stage of many different diseases producing prolonged patient immobilization or a hypercoagulative state. Lethal PTE is also one of the most frequent topics for suspected medical malpractice, especially when dealing with patients originally affected by non-critical illnesses and suddenly killed by a non-prevented embolic event. The crucial forensic question about a lethal PTE is the following one: was this lethal PTE an unpreventable complication or was it a consequence of real medical malpractice? Materials and methods: The authors analyzed the 1999-2009 autopsy archive of the Institute of Forensic Medicine of Milan University and selected all the cases where PTE was the cause of death. For every selected case, the authors also collected all the available demographic and clinical data. Statistical analysis was performed using SPSS V.16.00. Results: In the period 1999-2009, 129 (1.25%) cases out of a total of 10,288 autopsies were diagnosed as having suffered lethal PTE. The male to female ratio was 1:2 (34.1% versus 65.9%). The mean age at death was 67 +/- 18 years. In 41% of cases the death occurred outside of the hospital and in the absence of any medical support; in 36.5% of cases it occurred during the territorial paramedical support or during the very first evaluation in the emergency; and in the remaining 22.5% of cases it occurred during a period of hospitalization. In 33.4% of the selected cases, a typical preliminary event was positively identified: a pure major trauma (18.6%); a trauma followed by a major surgery (7%); a major non post-traumatic surgery (7%); and a non-surgical delivery. Symptoms suggesting PTE were detected in 46 cases (35.7%). Nine cases underwent a judicial autopsy in the same original hypothesis of a medical malpractice for incorrect prophylaxis in acutely bed-restricted patients. Conclusions: Post-surgical PTE cannot be automatically labeled a consequence of medical malpractice. The combination of correct prophylaxis, careful diagnostic monitoring of the high-risk patient and the correct therapy surely reduces the occurrence of lethal PTE, but it does not completely erase such an insidious pathology. In the hypothesis of a causative medical malpractice, only careful analysis by an experienced forensic pathologist can make a reliable distinction between an unpreventable complication and real medical malpractice.