Pulmonary thromboembolism is not uncommon--results and implications of a five-year study of 116 necropsies.

A retrospective study of 116 cases of fatal pulmonary thromboembolism, drawn from a total of 11,044 Coroner's autopsies, conducted over a 5-year period, yielded a necropsy prevalence of 1.05%, with an annual incidence varying between 0.78%-1.32%. There was a statistically significant peak monthly incidence of 1.89% in September (P < 0.03), as well as significantly higher rates between April to September as a whole, compared to the rest of the year (P < 0.03). There was a marked preponderance of females (male:female ratio = 0.59) and 48.3% of the subjects were > or = 60 years of age, with a distinct peak (23.3%) in the 8th decade. The prevalence of the common predisposing factors were as follows: surgery 41.4%, trauma 30.2%, sepsis 22.4%, obesity 18.1%, malignancy 10.3% and pregnancy 4.3%. The peak time of death following trauma and/or immobilization was one week. Apparently, a total of 54 subjects (46.6%) were ambulant prior to death, while 29 (25%) did not have any of the common risk factors studied. The prevalence of cigarette smoking and oral contraception could not be ascertained due to inadequate clinical documentation, even among medical inpatients. The majority of deaths (85.3%) occurred in hospitals, of which 44.8% were surgical patients. Pulmonary thromboembolism was apparently not suspected in 77.1% of the 105 patients who died whilst under the care of qualified medical practitioners, there being no significant difference between medical and surgical inpatients. In these cases, death was most often attributed to acute myocardial infarction or ischaemic heart disease. The study also showed a high prevalence of underlying chronic obstructive airways disease (37.1%) and of moderate to severe coronary atheroma (37.9%). The clinico-pathological and medico-legal implications of these findings are discussed.