Trauma vascular injury

Venous thromboembolism (VTE) is one of the most common cardiovascular disorders in the United States. VTE is manifested as deep vein thrombosis (DVT) and pulmonary embolism (PE) resulting from thrombus formation in the venous circulation (Fig. 7-1).1 It is often provoked by prolonged immobility and vascular injury and is most frequently seen in patients who have been hospitalized for a serious medical illness, trauma, or major surgery. VTE can also occur with little or no provocation in patients who have an underlying hypercoagulable disorder. 

Vascular injury may result from major orthopedic surgery (e.g., knee and hip replacement), trauma (especially fractures of the pelvis, hip, or leg), or indwelling venous catheters. 

Whole-body CT (WB-CT) protocols in multisystem trauma usually consist of a non-contrast enhanced head CT, which is followed by a contrast-enhanced chest and abdominal CT. For evaluation of the spine, reformations from the chest and abdomen are of diagnostic image quality if the primary colUmation was 2.5 mm or less, and dedicated scans of the spine are not obligatory (Mann et al. 2003). The cervical spine can be scanned separately with thin coUimations after the head scan, or can be included in the chest scan. The latter option has the advantage that the cervical vessels are contrast-enhanced, and vascular injuries can be ruled out from the same dataset, sparing one additional scan. 

With faster scanners, multiphase imaging is possible. Usually, WB-CT protocols for trauma comprised an arterial phase scan of the chest and neck, and a por-tovenous phase scan of the abdomen (Linsenmaier et al. 2002b Kanz et al. 2004 Wurm B et al. 2005). In cases of suspected pelvic fractures, arterial-phase imaging of the pelvis can be helpful to detect vascular injuries with active bleeding requiring intervention. If injuries of the abdominal aorta are suspected scanning the abdomen during arterial phase should be considered. 

No indication remains for angiography in the diagnostic evaluation of blunt abdominal trauma. On the one hand, the risk of the examination is relatively high. On the other hand, vascular injuries are extremely well depicted by the association of color Doppler ultrasound and MDCT. Angiography can be proposed in relatively rare instances when percutaneous treatment (embolization, angioplasty) appears to be the best option (Fig. 25.6). In the con-... 

When the extent of the trauma to the vessel is increased, the degree of vascular constriction is increased. Accordingly, a sharply cut blood vessel bleeds far more profusely than a blood vessel damaged by a more crushing injury. The vasoconstriction may last for many minutes or hours, thus... 

At present trauma is one of the three main causes of mortality along with cardiovascular and oncological diseases in the population of the Russian Federation. Amongst different variants of combined injuries, vascular-osseous injuries occupy a considerable place and are followed up by a high frequency of post operative complications (39 6%), amputations (up to 25%) and lethality (12-21%) [1-5]. 

Nakatani K, Takeshita S. Vascular endothelial cell injury by activated neutrophil and treatment for the injury. Surg Trauma Immunol Respon 1999 8 112-114. 

Q6 A thrombus is a blood clot which is fixed to the blood vessel wall. When it detaches and is carried in the blood, it is known as an embolus. Both thrombi and emboli can block blood vessels and deprive tissues of oxygen. In arteries blood clots usually form because the inner surface has been altered by deposition of atheroma. In contrast venous thrombosis results from slow or stagnant blood flow in veins, or defects in mechanisms which normally oppose inappropriate coagulation. Three major risk factors for pulmonary embolism are (i) venous stasis, (ii) hypercoagulability ofblood and (iii) injury to vascular endothelium following trauma or plaque rupture. 

In adults, a severe form of lung injury can develop in association with sepsis, pneumonia, and injury to the lungs due to trauma or surgery. This catastrophic disorder is known as acute respiratory distress syndrome (ARDS) and has a mortality rate of more than 40%. In ARDS, one of the major problems is a massive influx of activated neurophils which damage both vascular endothelium and alveolar epithelium and result in massive pulmonary edema and impairment of surfactant function. Neutrophil proteinases (e.g., elastase) break down surfactant proteins. A potential therapeutic strategy in ARDS involves administration of both surfactant and antiproteinases (e.g., recombinant a I -antitrypsin). 

The animal data are supported by some clinical observations with medicines that are known to block NMDA receptor activation, even if they have other pharmacological activities. Thus, low-dose ketamine reduced chronic pain associated with spinal cord injury (Hide et al., 1995) and could reduce pain in patients with peripheral nerve injury and with peripheral vascular disease (Felsby et al., 1996 Eisenberg and Pud, 1998). Amantadine could significantly reduce pain in cancer patients and in those with trauma-induced neuropathic pain (Pud et al., 1998). Although it is not possible to identify that the analgesic action of amantadine and ketamine in chronic pain states is through an action on the NMDA receptor, the clinical data do support the hypothesis that the animal data have gener-... 

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