Vascular damage
Introduction
Introduction to vascular injury Vascular injury (vascularinjury) is not only common in wartime, but also occurs in peacetime due to the rapid development of industry, agriculture, and transportation, as well as the increase in iatrogenic intubation and angiography. In the vascular injury of various parts of the body, the vascular damage of the extremities is more, followed by the neck, pelvis, chest and abdomen, and the arterial injury is more than the vein. basic knowledge The proportion of illness: 0.02% Susceptible people: no special people Mode of infection: non-infectious Complications: thrombosis, tetanus, gas gangrene, aneurysm
Cause
Cause of vascular injury
Violent injury (30%):
Any foreign direct or indirect violence to the blood vessels may cause open or closed vascular injury. The cause of vascular injury is complex, so the classification is also inconsistent. According to the force situation, it can be divided into direct injury and indirect injury.
Sharp and blunt damage (25%):
According to the injury factor, it can be divided into acute injury and blunt injury; according to the continuity of the damaged blood vessel, it can be divided into complete fracture, partial fracture and vascular contusion. According to the degree of vascular injury, it can be divided into light, medium and heavy injuries. Of course, no matter which classification, it can not fully summarize the whole picture of vascular injury.
Pathogenesis
Pathophysiology
In vascular injury, the vasculature is different, and the vascular injury is different. The pathological changes of vascular injury have different degrees of clinical manifestations and prognosis. Generally speaking, sharp injury can cause complete or partial rupture of blood vessels. Mainly with hemorrhage, blunt injury can cause damage to the intima of the blood vessel and the middle membrane to form a thrombus, which is mainly caused by obstructive changes.
(1) Arterial spasm: Most cavitation effects caused by blunt violence or high-speed bullets (600m/s) cause sympathetic nerve network to be stimulated to cause vascular smooth muscle contraction, long-term arterial spasm occurs, if its side Insufficient circulation can also cause ischemia or even necrosis of the limb.
(2) Arterial contusion: caused by blunt violence, common fracture, joint dislocation or acceleration-deceleration caused by shear stress, endothelium, medial membrane for excessive stretching, traction, and poor endurance caused by the intima The rupture causes extensive hematoma of the arterial wall, and the intima of the ruptured artery breaks into the lumen to form a thrombus.
(3) Arterial partial rupture: most of the sharp instruments are pierced by the outer wall of the blood vessel or the iatrogenic cannula causes partial rupture of the blood vessel. The pathological change is different from the complete rupture. The partially broken artery cannot be completely retracted into the surrounding tissue, and the artery is Retraction enlarges the gap, and the bleeding is more serious. If there is a direct pathway leading to the outside of the body or the body cavity, serious hemorrhage may occur, which may be life-threatening in a short period of time. The possibility of automatic bleeding stop is small or it may stop bleeding after a short time. Sometimes, the curled inner membrane can cause local thrombosis, cover the gap, and because other arterial walls remain intact, about 20% of the distal pulse can continue to exist, thereby masking the nature of arterial injury.
(4) complete rupture of the arterial vessel: the fully ruptured blood vessel retracts or retracts into the surrounding tissue, and the ruptured intima curls inward to form a thrombus. Usually, the amount of bleeding is small, but the limbs and viscera may occur due to interruption of blood supply. Ischemia, causing necrosis of limbs and organs.
(5) The formation of traumatic pseudoaneurysm: After the arterial part is broken, a hematoma is formed around the crack. After the hematoma is machined, the blood flow still communicates with the hematoma cavity. The circulation through the central arterial hole forms a pseudo-in the hematoma cavity. Aneurysm, the outer layer of the aneurysm is a mechanized fibrous tissue, the inner layer is a mechanical thrombus, and the tumor wall does not contain a normal 3-layer structure, which can cause rupture at any time, and can continuously apply thrombus to the distal end, resulting in a distal end. Ischemic changes.
(6) Formation of arteriovenous fistula: If the adjacent vein and artery are accompanied by injury, the blood flow of the artery flows to the low-pressure vein, forming a traumatic arteriovenous fistula. If it cannot be treated in time, it may cause circulatory system disorders. So that heart failure.
It should be noted that the patient's prognosis depends not only on the classification of vascular injury, but also on the location of vascular injury, the presence or absence of organ damage, the risk of wound infection, and the timing and conditions of treatment.
2. The location and frequency of vascular injury
Vascular injury is more common in men aged 20 to 40 years. The frequency of vascular injuries in the extremities is the first in the vascular injury of the whole body and is prone to disability. In 1964, Moris summarized the frequency of 891 cases of arterial injury in peacetime, and the limb arteries accounted for about 80%. The chest and abdomen large blood vessel injury has a high mortality rate and is difficult to rescue. The frequency of injury is more common in the descending aorta below the left subclavian artery bifurcation. Parmley reported 275 cases of aortic injury in 1959, left subclavian artery. The descending aorta injury slightly below the bifurcation accounted for 45%. In many cases, the arteries and veins were combined with the injury and combined with the damage of other organs.
Prevention
Vascular injury prevention
1. Do not drink alcoholic beverages for a long time, quit smoking and drinking hobbies, do not overeat pickles, sour, spicy and irritating foods, and banned mildew foods. It is more important for people with chronic pharyngitis to develop good eating habits. If you are less than enough, eat more fresh fruits and vegetables.
2. Maintain proper temperature and humidity in the cold season, pay attention to air circulation. Room temperature should be 20 ° C, do not cover too much bedding when sleeping at night, to avoid excessive temperature or excessive drying, causing throat discomfort. Do not sleep in the wind, take a break after strenuous labor, do not rinse the cold bath immediately. Those with acute pharyngitis caused by colds should drink hot water or ginger soup to increase sweating. Note that the stool is smooth. Timely treatment of acute inflammation, to prevent the evolution of chronic, chronically diseased organs, more likely to malignant.
Complication
Vascular injury complications Complications, thrombosis, tetanus, gangrene, aneurysm
1. Thrombosis: Arterial thrombosis, like vascular rupture, can cause gangrene in the distal blood supply disorder, which can cause sequelae of reflux obstruction.
2. Infection: Due to open injury, bacterial infection can be combined, and tetanus and gas gangrene can also occur.
3. Post-injury edema: tissue damage and residual veins and lymphatic drainage are blocked.
4. Pseudoaneurysm: After partial fracture of the artery, the hematoma around the rupture, the outer layer of the hematoma is formed into a cavity, and the arterial blood communicates with the hematoma cavity and gradually enlarges to form a traumatic pseudoaneurysm.
5. Traumatic arteriovenous fistula: simultaneous arteriovenous injury, high pressure arterial blood flow to the formation of traumatic arteriovenous fistula in the low pressure venous cavity, if not treated in time will cause circulatory disorders, heart failure.
Symptom
Symptoms of vascular injury Common symptoms Skin temperature reduces cyanosis Hematoma formation Chest pain Syringe murmur Dyspnea Abdominal pain Repeated bleeding Sensory dysfunction Bloating
Hemorrhage, shock, wound hematoma or distal limb ischemia is an early clinical manifestation of vascular injury. The condition is sharp and critical. The late stage of the lesion is mainly traumatic aneurysm and arteriovenous fistula. If other organs or tissue damage are combined, there will be corresponding Symptoms.
Bleeding
Sharp injury can be manifested as fresh blood flowing from the wound. If the red blood is sprayed or pulsating from the wound, it will indicate arterial injury. If dark red blood flows from the wound, it will indicate vein damage. It is worth noting that high-speed bullets or high speed. Metal fragments hit the bones, and all of their energy is released at the injured site. Therefore, although the wound at the surface is small, the internal damage is extensive, the bleeding is severe, and the weight of the heavy limbs (femur, tibia) is also curved. Or a sudden fracture will also produce a huge force, and the resulting vascular injury is also extensive and serious, and there are no obvious wounds on the body surface. It should also be noted that although wound bleeding can stop on its own, in most cases medium blood vessels The bleeding of the injury is intermittent, but it does not stop naturally. The blood vessel that is blocked by the thrombus can temporarily stop bleeding. However, if the thrombus is shocked by arterial pressure or wiped off by external force, it can be hemorrhage again. The vascular injury is blunt closed injury. The blood can flow into the body cavity such as the chest and abdomen, and although the body surface does not see bleeding, the injured person shows strict Hemorrhagic shock, this condition is often more serious than bleeding surface, higher mortality.
Shock
The cause of shock caused by vascular injury is complex, trauma and pain can aggravate shock, but the most basic cause is still hemorrhagic shock caused by bleeding, whether it is blunt or sharp injury, whether open or closed Injury can cause hemorrhagic shock, open injury can roughly estimate the amount of blood loss, closed injury is difficult to estimate the amount of blood loss, full or partial fracture of large blood vessels often die at the scene, a few have a chance due to clot blockage Go to the hospital for treatment.
3. Hematoma
The path of bleeding after vascular injury can flow to the interstitial space to form a hematoma. In most cases, it flows to the body surface or body cavity, and flows to the interstitial space to form a hematoma plus hemorrhage; if the bleeding flows to the mediastinum It shows the widening of the mediastinum, difficulty in breathing, chest pain, etc.; if it flows to the posterior peritoneum, it can cause abdominal pain, abdominal distension, etc. The hematoma is characterized by high tension, firm and unclear edge, or the hematoma communicates with the vascular hole to form a traffic hematoma. Hematoma has swelling and pulsation, which is a local important sign for the diagnosis of blunt vascular trauma, such as slashing, can cause disastrous consequences.
4. Tissue ischemia performance
Thrombosis caused by limb arterial rupture or intimal injury can cause obvious ischemia in the distal part of the limb, the so-called "5P" performance:
1 arterial pulsation weakened or disappeared;
2 distal limb ischemic pain;
3 skin blood flow decreased pale, skin temperature decreased;
4 limb sensory nerve ischemia and numbness;
5 limb motor nerve loss function muscle paralysis, it should be noted that about 20% of patients with arterial injury can still feel the pulse, because the damage clot block the gap can maintain the continuity of blood flow, and because the pulse wave is A pressure wave with a wave velocity of up to 10 m/s, so it can pass over the intima of the blood vessel, and a limited fresh blood clot can be transmitted to the distal end through the circumflex circulation.
5. Tremor and murmur
When there is a traffic hematoma in the injured area and the stenosis of the arterial injury site, the auscultation can be heard and the systolic murmur, and the tremor is felt when palpation. In the case of traumatic arteriovenous fistula, the blood flow back and forth continuous murmur can be heard.
6. Combine the symptoms of organ or nerve tissue damage
When vascular injury is combined with other organs (such as lung, liver, brain, kidney, etc.) or nerve tissue damage, the symptoms appear are diverse. It should be noted that the damage of the limb nerve and the sensory disturbance caused by ischemia are different. The former is distributed according to the area dominated by the nerves, and the latter is distributed in a sock-like manner.
Examine
Vascular injury examination
1. Arterial Doppler examination: audible abnormalities in arterial blood flow, such as weakened sound, disappearance, systolic murmur (aneurysm) or continuous murmur (arteriovenous fistula).
2. Color ultrasound exploration: It can detect the direction of blood flow, velocity, vascular diameter change, continuity, presence or absence of rupture, stenosis and thrombosis. In pseudoaneurysm, sonogram can be seen in arterial trauma. The echoes have a clear border with no clear capsule echo.
3. Angiography: Arterial puncture cannulation can show the rupture of the artery. When the rupture occurs, the contrast agent can flow out of the vascular cavity. When the artery is completely ruptured, the proximal artery may form a thrombus to show the interruption of blood flow, or the flow of contrast agent. The extravascular and distal arteries are not developed. There are thrombus and blood clots in the aneurysm. The angiography can show irregular images. The arteriovenous angiography can clearly identify the location, size, blood vessels and collateral circulation of the fistula. Venous dilatation is evident, and the distal end can show increased venous and varicose veins.
According to the above examinations, the diagnosis of vascular injury is not difficult, but when the fracture, severe crush injury, chest and abdominal cavity injury is difficult to diagnose, it should be noted that in the complicated situation to determine whether the blood vessel is damaged, and can not ignore other organs. damage.
Diagnosis
Diagnostic identification of vascular injury
diagnosis
Simple acute vascular injury is based on traumatic violence, injury site, acute bleeding of the wound and ischemic changes at the distal end of the limb, distal arterial pulsation disappears or limb swelling, cyanosis and other clinical manifestations, the diagnosis is not difficult, but with a merger Injury or blunt trauma caused by arterial intimal contusion, when the limb ischemic symptoms are not obvious, the diagnosis may be covered by the symptoms of the combined injury, and the vascular exploration is not performed in time, so in the treatment of complex damage, be alert to vascular injury The possibility of existence and the clinical features familiar with vascular injury, generally in the following cases, should be suspected of vascular injury and should be vascular exploration:
1 spray or pulsatile bleeding and repeated bleeding;
2 large or progressively enlarged hematoma, such as pulsatile hematoma;
3 unexplained shock;
4 There is a distal blood supply disorder after blunt injury, suspected arterial intimal contusion secondary to thrombosis;
5 fractures and large joint injuries along the vessel's path and its adjacent sites, and those with distal blood supply disorders.
Differential diagnosis
Acute vascular injury is not difficult to diagnose according to the clinical manifestations of traumatic violence, wound site, acute blood loss of the wound and ischemic changes of the distal limb. However, in the case of combined or blunt trauma, the symptoms of the combined injury are not covered or not. Clear wounds and dominant blood loss may miss the diagnosis of vascular injury. Generally, the possibility of vascular injury should be guarded under the following conditions:
1 spray or pulsation and repeated bleeding;
2 a large or progressively enlarged hematoma, especially a pulsatile hematoma;
3 unexplained shock;
4 After blunt injury, there is a blood supply disorder at the distal end of the injury site;
5 near the vascular vascular fracture and large joint damage, and there is a blood supply to the distal limb;
6 Patients with a deceleration injury such as a fall injury or a car accident should consider the possibility of aortic or visceral artery injury.
