Fibroid Embolism

The characteristic symptom of pulmonary embolism issudden breathlessness. Indeed, relatively few processescause such sudden dyspnoea.Lateral, usuallybasal, pleuritic chest pain and haemoptysis develop sometime after the onset of breathlessness, and are only clinicalfeatures if infarction has occurred. The haemoptysis consistsof frank red blood without sputum. In addition to respiratorysymptoms there may be pain or swelling of a leg,suggesting deep vein thrombosis, or a history indicating anincreased risk of thrombosis.On examination there may be signs of deep vein thrombosis.The respiratory rate is usually raised, and if infarctionhas taken place there may be a pleural rub and a smallpleural effusion.

If embolization has been extensive therewill be cyanosis and signs of cardiovascular stress. The mostimportant cardiovascular sign is a tachycardia, and somepatients will have an elevated jugular venous pressure anda fourth heart sound. With extensive embolism patientsmay have signs of pulmonary hypertension, and occasionally a systolic murmur can be heard over the lung fields,as a consequence of turbulent pulmonary blood flow pastpartial pulmonary arterial occlusion.

Within a few hours ofpulmonary infarction fever is the rule.Arterial blood gas analysis usually demonstrates hypoxaemia.However, not all patients are hypoxaemic andhypoxaemia is in itself a very non-specific abnormality. Asa consequence of hyperventilation, there is hypocapnia.Patients with pulmonary embolic disease are frequentlyanxious as well as breathless, and their hypocapnia is notuncommonly taken to reflect anxiety. However, anxietyhyperventilation syndromes produce hyperoxaemia.Immediately following embolization there is often bronchoconstriction,there may even be wheeze, and later, areduction in surfactant in the affected lung is a contributoryfactor to atelectasis.Symptomatic pulmonary embolism occurs in about30% of patients with deep vein thrombosis in the leg orpelvis; if asymptomatic events are added to this figureabout 50-60% of patients with deep venous thrombosiswill have a pulmonary embolism at some stage. However,in patients with suspected deep venous thrombosis only25% will actually prove to have the condition when fullyinvestigated.