The origin of fatal pulmonary emboli: a postmortem analysis of 500 deaths from pulmonary embolism in trauma, surgical, and medical patients

Abstract Background The traditional theory that pulmonary emboli (PE) originate from the lower extremity has been challenged. Methods All autopsies performed in Los Angeles County between 2002 and 2010 where PE was the cause of death were reviewed. Results Of the 491 PE deaths identified, 36% were surgical and 64% medical. Venous dissection for clots was performed in 380 patients; the PE source was the lower extremity (70.8%), pelvic veins (4.2 %), and upper extremity (1.1%). No source was identified in 22.6% of patients. Body mass index (adjusted odds ratio [AOR] 1.044, 95% confidence interval [CI] 1.011 to 1.078, P = .009) and age (AOR 1.018, 95% CI 1.001 to 1.036, P = .042) were independent predictors for identifying a PE source. Chronic obstructive pulmonary disease (AOR .173, 95% CI .046 to .646, P = .009) was predictive of not identifying a PE source. Conclusions Most medical and surgical patients with fatal PE had a lower extremity source found, but a significant number had no source identified. Age and body mass index were positively associated with PE source identification. However, a diagnosis of chronic obstructive pulmonary disease was associated with no PE source identification.