On a mathematical theory of embolism

A theory of embolism based on an optimization model of blood flow is proposed and used to explain the topographic distribution of emboli in arterial trees.     

Venous air embolism during a craniofacial procedure

The possibility of venous air embolism exists whenever the craniofacial operative field is above the level of the heart. Craniotomy with the high-torque craniotome is hypothesized to have produced venous air embolism in the patient described in this report. The diagnosis of venous air embolism is determined by transesophageal Doppler probe, transesophageal echocardiogram or external echocardiogram, and end-tidal N2 and CO2 determinations. Treatment includes control of the air entry sites, aspiration of air from the right atrium via a catheter placed prior to operation, and discontinuing nitrous oxide. If these measures are unsuccessful, the operative field should be transposed below heart level and the procedure terminated. In the event of significant hemodynamic compromise, closed cardiac massage should be tried; if that fails, open cardiac massage and direct aspiration are necessary. The true incidence of venous air embolism in craniofacial operations may be much higher than previously suspected. We therefore recommend placement of appropriate monitoring equipment to detect intracardiac air in those major craniofacial procedures in which there is a potential for intravascular air ingress.     

Fat embolism: a rational approach to treatment

Fat embolism following major trauma may be associated with a clinical syndrome with widespread pulmonary and systemic manifestations, the most serious being profound hypoxia with secondary atelectasis, pulmonary edema and pulmonary hypertension, and cerebral depression. Though the origin of the embolic fat is debated, there is evidence to support its origin from both the bone marrow and intravascular chylomicron coalescence.The clinical manifestations are largely explained by a prime assault upon the lung parenchyma and alteration in platelet characteristics.Early recognition and treatment of the condition is essential, adequate oxygenation being of prime importance. Steroids and heparin have been found to be of benefit.     

Pulmonary embolism caused by a migrated gunshot projectile

Pulmonary embolism caused by a foreign body is an exceedingly rare event. We report on a 62 year old woman who suffered a gun shot injury to her left knee with concomitant vascular lacerations. The bullet migrated through the venous system into the pulmonary circulation causing a pulmonary embolism. The projectile remained stationary for ten years. Taking into consideration that she is virtually asymptomatic and that regular follow up examinations showed no further migration of the foreign body, we opted for a conservative venue of management.     

Cerebral thrombosis and embolism; a method of treatment

Acute cerebral thrombosis and embolism give rise to arterial spasm, edema, and anoxia of the cerebral tissues supplied by the affected artery or arteries. Sympathetic block induced by injecting the stellate ganglion with procaine appears to relieve spasm and results in improved cerebral circulation and clinical improvement in a significant number of cases. Sympathetic block should be combined with the usual supportive measures and not infrequently with anticoagulants. Every effort should be made to institute treatment as soon as possible after the onset of symptoms.     

Therapy of pulmonary embolism

The therapeutic regimen in acute pulmonary embolism of different severity is discussed. Heparin is indicated in patients with only small and submassive embolism without impairment of the circulation. Fibrinolysis is the therapy of choice in submassive pulmonary embolism with circulatory insufficiency and massive embolism. In fulminant embolism with circulatory shock or cardiac arrest embolectomy should be performed. If the course of lung embolism is subacute, fibrinolysis may improve the late prognosis in respect to chronic pulmonary hypertension.