Gonzales et al. list asthma and pulmonary embolus as causes of asphyxia.59 These two conditions are not fatal as often as they formerly were, but still represent a significant number of deaths due to respiratory disease. Death from massive pulmonary thromboembolus is due to impaction of dislodged thrombi in the pulmonary artery or its main tributaries (Figure 3.14). Thrombosis has been classically described as being caused by three factors: stasis, injury to a vein, and hypercoagulability. Most pulmonary thromboem-boli originate in the deep veins of the lower extremities. Occasionally, they will arise in the pelvic veins, especially in pregnant women. In one case, the source of the embolus was a pelvic vein in a woman who had a serocystad-enoma the size of a basketball pressing on the vein. Any trauma to the lower extremities or pelvis may injure a vein and cause the formation of thrombi, which can be subsequently dislodged.
Stasis is a cause for the formation of thrombi, with the classic example the individual confined to bed. Thrombi can develop in individuals who are in bed following a traumatic injury that does not involve a vein of the lower extremity or pelvis. Thus, an individual might be in bed for a head injury, develop thrombosis of the veins of the lower extremities, and throw
a massive pulmonary thromboembolus. Here, even though the mechanism of death is natural, i.e., a pulmonary thromboembolus, the manner of death would be accident because the individual was confined to the bed due to trauma. If the individual had been assaulted, then the case would be classified as homicide.
Death from massive pulmonary thromboembolus is caused by a combination of mechanical obstruction of the blood flow by the embolus plus vasoconstriction that further reduces the lumen of the pulmonary arteries. Symptoms of massive pulmonary thrombolus are syncopy, chest pain, and dyspnea. Approximately one third of the people dying of massive throm-boemboli die within an hour. In all deaths due to massive thromboemboli, the source of the emboli should be sought. The veins of the pelvis and legs must be examined. Incisions should be made bilaterally into the popliteal fossae and calves.
There has recently been speculation that hereditary thrombotic disease, manifested by the presence of factor V Leiden and factor II/20210A alleles coupled with acquired factors, accounts for a large number of fatal cases of pulmonary thromboemboli. A number of studies, however, have shown that the incidence of factor V Leiden and factor II/20210A allele in patients with fatal pulmonary thromboemboli is not greater than the incidence of these factors in the general population.63,64
Was this article helpful?
Do You Suffer From ASTHMA Chronic asthma is a paralyzing, suffocating and socially isolating condition that can cause anxiety that can trigger even more attacks. Before you know it you are caught in a vicious cycle Put an end to the dependence on inhalers, buying expensive prescription drugs and avoidance of allergenic situations and animals. Get control of your life again and Deal With Asthma Naturally