Khaled Mahmoud El-Shami, M.B.Ch.B., M.S., Ph.D.

• Assistant Professor of Oncology

https://www.hopkinsmedicine.org/profiles/results/directory/profile/10003928/khaled-elshami

Similarly blood pressure log excel buy 2 mg coumadin with amex, the repair is not extended proximally into the arch arrhythmia for dummies buy coumadin 5 mg on-line, even if the primary tear is located there hypertension 6 weeks postpartum coumadin 5 mg buy free shipping, unless the arch is substantially dilated pulse blood pressure normal cost of coumadin. Because surgery for acute type B dissection carries an increased risk of postoperative paraplegia hypertension recommendations buy generic coumadin pills, adjuncts that provide spinal cord protection are used liberally. Cerebrospinal fluid drainage and left heart bypass are often used, even when the planned repair is limited to the upper descending thoracic aorta. Proximal control is usually obtained by placing a clamp between the left common carotid and left subclavian arteries. Manipulation of mediastinal hematoma around the proximal descending thoracic aorta is avoided until proximal control is established. The aorta is opened, and the dissecting membrane is removed from the segment being replaced. The proximal and distal anastomoses incorporate all layers of the aortic wall, thereby obliterating the false lumen with the suture lines and directing all blood flow into the true lumen. Although there are usually multiple patent intercostal arteries, the extreme tissue fragility often precludes their reattachment. Outcomes Aggressive pharmacological management has led to a substantial decrease in mortality for patients with acute distal aortic dissection. Still, some 10% to 20% of medically treated patients without acute complications at the time of presentation die during the initial treatment phase. Risk factors associated with medical treatment failure include a large entry tear, enlarged aorta, persistent hypertension despite maximal treatment, oliguria, and peripheral ischemia. Patients undergoing surgery for acute type B dissection are a high-risk group that includes patients with rupture, neurological dysfunction, renal failure, and peripheral ischemia. Therefore, it is not surprising that results after surgery for acute complicated type B dissection are often worse than those of medical therapy. Despite the early survival advantage with nonoperative management compared with surgical treatment, long-term results are similar in patients in both groups. The reported actuarial survival rates with nonoperative management are 76% at 5 years and 56% at 10 years. The rationale for careful surveillance lies in the natural history of the disease. Rupture and ischemic events related to the dissection are responsible for most late deaths, and therefore surgical intervention is eventually required in approximately one-third of patients. Indications for Operation Operative repair for a chronic type B aortic dissection is required in the setting of those patients for whom medical management was initially successful but who subsequently develop an indication for surgery. Patients who underwent successful type A dissection but have residual descending dissection also frequently require intervention. Although subsequent malperfusion or ischemic events can occur in a chronically dissected aorta, the majority of patients will require operative intervention for aneurysmal degeneration of chronic dissection. Although the entire thoracoabdominal aorta may be dissected, the mere presence of dissection in the descending aorta is not an indication for surgical intervention. In asymptomatic patients, an elective operation is considered when the aneurysmal segment has reached 5. A lower threshold is reserved for patients with connective tissue disorders, including Marfan, Loeys-Dietz, and other familial aortic syndromes. Patients with symptomatic aneurysms are at increased risk of rupture and deserve expeditious evaluation and treatment. The onset of new pain in a patient with a known aneurysm is particularly concerning and may herald significant expansion, leakage, or impending rupture. Emergent surgery is reserved for patients with clinical signs or imaging findings of rupture. Operative strategies are considerably different in emergent versus elective procedures. Patients with chronic dissection who require emergency open surgical repair because of acute pain or rupture undergo limited graft replacement of the symptomatic segment. Although the entire thoracoabdominal aorta may be dissected and aneurysmal, typically a relatively localized segment is the cause of the symptoms. Preoperative Assessment A detailed preoperative assessment of physiological reserve is critical. All patients should undergo a thorough evaluation before undergoing elective operation, with a focus on baseline cardiovascular, pulmonary, and renal function. Cardiovascular Status Ischemic heart disease is common in patients with thoracic aortic disease and contributes to a substantial proportion of early and late postoperative deaths. In addition, valvular pathology and ventricular dysfunction have important implications when planning anesthetic management and strategies for aortic repair. Nuclear stress tests or myocardial perfusion studies are used selectively to identify reversible myocardial ischemia. Cardiac catheterization with coronary arteriography should be considered in patients who have evidence of coronary disease or a depressed ejection fraction. The hemodynamic changes that occur during thoracic aortic repair can precipitate stroke in patients with significant cerebrovascular disease. Therefore, carotid duplex ultrasound studies are also routinely obtained to detect occult carotid artery stenosis. It is recommended that significant carotid artery stenosis be corrected with an endarterectomy before proceeding with the aortic operation. Pulmonary Status the most common complication after descending thoracic and thoracoabdominal aortic repairs is pulmonary dysfunction, with prolonged ventilator dependence and the need for tracheostomy. In selected patients, borderline pulmonary function can be improved with a 1- to 3-month regimen that includes smoking cessation, exercise, weight loss, and treatment of bronchitis. In most cases, operation is not withheld in patients with symptomatic aneurysms and poor pulmonary reserve. Surgical techniques, however, can be modified to improve the chance of recovery in these high-risk patients. For example, precautions can be taken to ensure preservation of the left recurrent laryngeal and phrenic nerves. Patients with severely impaired renal function frequently require at least temporary hemodialysis after operation; these patients are also at increased risk of death. Surgical Repair Operative Techniques Surgical strategies are determined on the basis of the extent of the aneurysm being repaired. A double-lumen endobronchial tube is used to allow selective single lung ventilation. Retroperitoneal exposure of the thoracoabdominal aorta is achieved by dividing the diaphragm and retracting the peritoneal contents medially. Extent I repairs begin in upper descending thoracic aorta, often near left subclavian artery, and extend to region of visceral and renal arteries. Cold perfusion is delivered to kidneys through catheters placed in renal arterial ostia. In patients who have undergone previous coronary artery bypass surgery using the left internal thoracic artery, clamping proximal to the left subclavian artery can induce severe myocardial ischemia. When clamping at this location is anticipated, a left common carotid-to-subclavian bypass is performed preoperatively to avoid cardiac complications. In certain situations, such as contained rupture, an extremely large aneurysm, or extension into the distal transverse arch, there is no suitable proximal clamp site, and hypothermic circulatory arrest is required. Because of the periaortic inflammation caused by the dissection, the vagus and left recurrent laryngeal nerves are often adherent to the aortic wall and susceptible to injury during repair of the proximal descending segment. Careful dissection of the proximal descending thoracic aorta from the underlying esophagus before performing the proximal anastomosis minimizes the risk of esophageal injury and development of aortoesophageal fistula. The aortic branch vessels-including the intercostal, celiac, superior mesenteric, renal, and lumbar arteries-are reattached to the prosthetic graft, either via patch anastomosis or individual vessel reimplantation. When dissection extends into the visceral or renal arteries, the membrane can be fenestrated or the false lumen can be obliterated using sutures or intraluminal stents. Asymmetrical expansion of the false lumen often displaces the left renal artery laterally enough to require separate reattachment or use of a side branch graft. If the dissection stops at the level of the visceral vessels, the distal anastomosis can be beveled to include the abdominal branches. Although it is tempting to resect as much of the dissected aorta as possible, risks of the operation, including paraplegia, are incrementally increased with the greater extent of aortic replacement. Adjacent dissected aorta that is not aneurysmal is fenestrated by resecting wedges of the dissecting membrane proximally and distally from within the aortic cuffs, allowing blood to flow through both true and false channels after the reconstruction is completed. The distal anastomosis is performed at the proximal most level of non-aneurysmal aorta. Organ Protection Clamping the descending thoracic aorta creates ischemia of the spinal cord and abdominal viscera. Clinically significant postoperative manifestations of hepatic, pancreatic, and bowel ischemia are relatively uncommon. Acute kidney injury and spinal cord injury, however, are the main causes of morbidity and mortality after these operations. Therefore, several aspects of the operation are devoted to minimizing spinal and renal ischemia (Box 33. Cerebrospinal fluid drainage improves spinal perfusion by reducing cerebrospinal fluid pressure and has been shown to be beneficial by a randomized clinical trial. Left heart bypass is employed by placing an angled-tip cannula in the left atrium via the inferior pulmonary vein. Oxygenated blood is returned to the patient via an arterial cannula placed in either the femoral artery or distal aorta. Alternatively, full cardiopulmonary bypass can be established using the femoral vein and artery. In instances where hypothermic circulatory arrest will be necessary, it is important to ascertain any baseline aortic valve insufficiency. Potential benefits of reducing hepatic and bowel ischemia include reduced risks of postoperative coagulopathy and bacterial translocation, respectively. These outcomes are significantly better than those obtained in patients who undergo surgery during the acute phase. Optimizing organ perfusion, especially to the spinal cord, requires appropriate oxygen delivery. Therefore, careful invasive monitoring of blood pressure, cardiac output, and hemoglobin levels is necessary. Mean arterial blood pressure is targeted at 80 to 90 mm Hg; however, optimal organ perfusion must be balanced against the risk of bleeding. Aortic tissue in the setting of dissection is extremely thin and fragile, and bleeding risk is significant. Excess postoperative hypertension can precipitate severe bleeding or pseudoaneurysm formation. Therefore, during the initial postoperative phase, aggressive blood pressure regulation is maintained with infusion of short-acting vasoactive agents. Appropriate volume resuscitation is usually required to address hypotension, with inotropes and vasopressors used judiciously. While preventing hypertensive episodes, maintaining adequate blood pressure, preload, and cardiac inotropic state are important in preventing delayed paraplegia and postoperative renal failure. In the absence of postoperative bleeding, blood pressure should be kept near its preoperative baseline level. In the postoperative period, strategies to reverse paraplegia include inducing systemic hypertension, decreasing cerebrospinal pressure by cerebrospinal fluid drainage, correcting anemia, preventing fever, and administering cardiac inotropes, mannitol, and steroids. Atrial tachyarrhythmias are common after extensive aortic reconstruction and may precipitate acute hypotension. However, synchronized cardioversion should be used liberally and expeditiously to restore sinus rhythm promptly and correct hypotension. Recovery from paraplegia is possible, but if cord function does not return promptly after these measures are taken, such a recovery is not likely. Aortic graft infections are a threat to anastomotic integrity and are associated with extremely high morbidity and mortality. Definitive treatment often requires complete removal of the graft and complex vascular reconstruction. Resulting hoarseness is a concern that affects both voice and postoperative pulmonary toilet. Vocal fold medialization with silicon injection can improve functional status and should be performed early before discharge. An exception would be in the event of anticipated reintubation for a planned subsequent operation, such as completion of an elephant trunk. Thyroplasty can be definitive treatment; however, reintubation can potentially disrupt the thyroplasty. Therefore, this treatment is reserved for the outpatient setting when the patient has recovered from the operation yet remains hoarse. Newer prophylactic therapies are being explored to lessen the risk of patients developing paraplegia after thoracic aortic replacement. Targeted stem cell therapy may offer hope for those patients who suffer this dreaded complication. In the setting of rapidly evolving endovascular technology, previously untreatable patient conditions can be addressed with innovative treatment strategies that involve hybrid approaches to complex aortic arch and thoracoabdominal aortic pathology. As further experience is gained with branched and fenestrated aortic endografts, more complex aortic pathology will be treatable with endovascular approaches, obviating the need for open aortic replacement. The ascending aorta and aortic root represent the next frontier in endovascular therapy. Furthermore, greater understanding of the molecular pathways that underlie aortic dissection may uncover novel medical treatments that reduce the rate of aortic expansion and the risk of fatal rupture. Acute type A dissection in octogenarians: does emergency surgery impact in-hospital outcome or long-term survival. Differences in clinical presentation, management, and outcomes of acute type A aortic dissection in patients with and without previous cardiac surgery.

The broad antibacterial spectrum blood pressure near death coumadin 1 mg online, excellent tissue penetration blood pressure medication for pregnant coumadin 5 mg on line, and low toxicity of the fluoroquinolones make them potentially ideal agents for the prophylaxis of surgical infections hypertension with bradycardia discount coumadin 2 mg free shipping. Limited data are available concerning the use of fluoroquinolones for this indication blood pressure vitamin d buy coumadin us, but there are reports of efficacy equal or superior to that of cephalosporin antibiotics in the prophylaxis of colorectal pulse pressure 29 order 5 mg coumadin mastercard,94,95 biliary 94,96 and urologic surgery 97-99 Auger. One patient who received cefazolin developed mediastinitis from a cefazolinresistant strain of S. As yet, there are no published clinical trials of a fluoroquinolone versus a cephalosporin in the prophylaxis of peripheral vascular surgery procedures. Resistant Bacteria the contemporary use of antibiotics has resulted in further progression of bacterial resistance so that methicillin-resistant species of Staphylococcus are encountered more frequently Institutional bacteriologic analysis may reveal an increased incidence of. Attention to patient preparation, skin cleansing, hand disinfection, surgical site care, and sterile technique are emphasized. In addition, recommendations for the selection and use of antibiotics are proposed. The use of daptomycin (a bactericidal cyclic lipopeptide) with cefazolin has been advocated. In another prospective study low-risk patients undergoing elective vascular, interventions were randomized to receive cefazolin, cefazolin and vancomycin, or cefazolin and daptomycin for prophylaxis. Patients in the cefazolin and daptomycin group had fewer infections compared to the other two groups. However, high-risk patients were not included in this study 106 Recommendations for the first-line use of. Daptomycin has a favorable side-effect profile compared to vancomycin as well as short infusion time but higher cost. Patients received a loading dose of vancomycin 12 hours prior to the surgery followed by a 24-hour infusion. It was seen that vancomycin achieved adequate serum concentrations in these patients. Pharmacokinetic studies suggest that prophylactic antibiotics should be administered more frequently and in higher doses during surgery than is recommended for routine therapeutic indications. The advantage of continuing coverage beyond the operating room, however, has not been clearly demonstrated. In the absence of these risk factors, there is clearly no advantage in extending antibiotic prophylaxis for longer than 24 hours. Regimens of prophylaxis should be tailored to the type of vascular reconstruction undertaken. Cefazolin prophylaxis is recommended in all procedures involving the placement of prosthetic materials. It is probably not necessary in "clean" vascular procedures of the neck and upper extremities that do not involve the use of synthetic grafts. In contrast, the marked colonization and favorable bacterial environment of the lower abdomen and groin necessitate the use of antibiotic prophylaxis in all aortofemoropopliteal vascular procedures. The risk of gram-negative infection in aortic reconstruction may necessitate the addition of an aminoglycoside, particularly in institutions with a high degree of cefazolin resistance among gram-negative isolates. Alternatively a second- or third-generation cephalosporin with broader anti­gram, negative activity may be substituted because this obviates the risk of aminoglycosideassociated nephrotoxicity. Cephalosporins should be avoided in patients with a history of anaphylaxis to -lactam antibiotics. Patients with a history of minor allergic reactions to penicillin antibiotics can be given a cephalosporin test dose to determine whether cross-reactivity is present. Reduced dosing of cefazolin and most other cephalosporins is recommended in renal insufficiency based on the calculated creatinine clearance. Accordingly oral prophylaxis is recommended for procedures that are highly associated, with bacteremia, such as tooth extraction, cystoscopy and colonoscopy Wooster and. For procedures such as tooth extraction and colonoscopy prophylaxis must be tailored to the, most common normal flora of the traumatized site. Penicillins are appropriate choices for major dental procedures, whereas broader gram-negative and anaerobic coverage may be warranted in colonoscopy It should be emphasized, however, that the true risk of. Primary Arterial Infections A primary arterial infection is a condition in which an infectious agent invades and destroys the wall of an artery resulting in disruption of the normal arterial architecture, and pseudoaneurysm formation. Ultimately these lesions can result in symptoms resulting from sepsis, compression, erosion, embolization, thrombosis, or hemorrhage. The essential features include the destruction of the arterial wall by an infectious process, septic illness, and rapid onset of pseudoaneurysm formation. Successful management requires familiarity with the processes involved and the ability to make prompt decisions at the time of surgery The. In 1885, Osler112 presented the first comprehensive description of this relationship. In addressing the Royal College of Physicians, he described a 30-year-old man who had died from fever, chills, and pneumonia. At autopsy, the patient was found to have endocarditis involving the aortic valve, as well as multiple aneurysms of the thoracic aorta. Based on carefully described pathologic findings, Osler proposed a causal relationship between infection of the aortic wall and subsequent aneurysm formation. Because of a similarity between the beaded appearance of these aneurysms and fungal vegetations, he introduced the term mycotic aneurysm and thus the concept of primary arterial infection. Definitions There is no universally accepted definition of primary arterial infection. Moreover, there continues to be confusion regarding the general classification of infections that involve the native arterial tree. Although the term mycotic aneurysm initially signified an infected aneurysm found in association with bacterial endocarditis, it has come to denote an infected aneurysm of any type. Another problem is that there is considerable disparity among the several definitions that have been proposed. Finally it should be recognized, that, with the exception of a secondarily infected arterial aneurysm, most of these lesions are actually infected pseudoaneurysms. Most lesions arise by means of the local destruction of the arterial wall and the fibrous encapsulation of an expanding hematoma; therefore, these lesions do not have the histologic components of an arterial wall. For practical purposes, primary arterial infection can be defined as the direct invasion of a pathogen into the wall of a native artery irrespective of the preexisting state of the, underlying artery or source of the pathogen. The term mycotic aneurysm is used to denote both true aneurysms and false aneurysms that are associated with infection of the arterial wall. Pathogenesis Five basic mechanisms have been implicated in the development of primary arterial infections. They can be grouped broadly as (1) oslerian mycotic aneurysms, (2) microbial arteritis with aneurysm formation, (3) infected aneurysms, (4) arterial injury with contamination, and (5) arteritis from contiguous spread. Oslerian Mycotic Aneurysms: Embolization of Infected Cardiac Vegetations Osler, in coining the term mycotic aneurysm, both named the condition and described what would be the most prevalent cause of primary arterial infection in the preantibiotic era. As he described it, a mycotic aneurysm is limited to the unique clinical condition characterized by bacterial endocarditis with septic embolization from valvular vegetations. These septic emboli lodge within the arterial wall, where a suppurative infection develops. The arterial wall is destroyed by the infection, and the resultant pseudoaneurysm is recognized as a mycotic aneurysm. Considerable confusion has arisen because the term mycotic aneurysm has been expanded and applied to various types of infected aneurysms. He introduced the term primary mycotic aneurysm to refer to infected aortic aneurysms not associated with endocarditis or an infectious focus; secondary types were those that formed as a result of preceding endocarditis. Ponfick114 and Eppinger115 were among the first to characterize the anatomic features of these aneurysms pathologically Ponfick114 proposed that the. Eppinger in 1887 provided further support for the theory of septic emboli by culturing the same strain of bacteria from both vegetative lesions and the wall of an aneurysm in a patient with endocarditis. He applied the term embolomycotic to describe the combination of infectious and embolic components that led to the formation of mycotic aneurysms. Microbial arteritis with aneurysm formation occurs when a normal or atherosclerotic artery becomes infected and the weakened artery becomes aneurysmal. In 1906, the German pathologist Weisel116 described distinctive pathologic changes in arterial walls that occurred during the course of an infectious disease, but were not related to cardiac valve vegetation emboli. Crane113 described an infected aneurysm in a patient with hypoplasia of the aorta, but no associated bacterial endocarditis or other identifiable source of infection. This resulted in an arterial infection, disruption of the aortic wall, and an infected pseudoaneurysm. Revell extended the concept of aortic bacterial seeding one step further and proposed that the route of infection was through the aortic vasa vasorum. Infected Aneurysms the term infected aneurysm refers to an infection of a preexisting aneurysm, most often by hematogenous microbiologic seeding of the aneurysm. The original aneurysm is most commonly atherosclerotic; however, it may also be the result of trauma or arteritis. The diseased artery becomes host to bacterial pathogens when these lodge within the intramural thrombus and arteriosclerotic intima. Arterial Injury With Contamination Another cause of arterial infections is mechanical arterial injury by contaminated instruments. This type of infection can occur after an inadvertent arterial puncture with a contaminated needle in a drug abuser, as an accidental contamination during radiologic procedures, during placement of hemodynamic monitoring catheters, or as a result of traumatic injury the combination of mechanical disruption of the intima and seeding of. Arteritis From Contiguous Spread Arterial infections can also develop through the spread of infection from a contiguous focus. Contiguous infections that have been recognized as potential sources of bacteria include lesions such as osteomyelitis, infected lymph nodes, tuberculous lymph nodes, and abscesses from narcotic injection. They subsequently produce a necrotizing invasive infection of the arterial wall, with eventual destruction of the wall. Because of significant differences in the pathogens and pathogenesis of these lesions, they merit separate discussion. These lesions occur in approximately 10% of patients with the tertiary form of the disease. The reasons why Treponema species prefer this portion of the aorta remain unclear. After spirochete penetration, an infiltrate develops within the vessel wall consisting of plasma cells, epidermal cells, and giant cells. This infiltrate results in destruction of the elastic and muscular components of the tunica media, replacement of the normal wall with fibrous tissue, and dilation and subsequent formation of saccular aneurysms. Fungal arterial infections are also extremely rare and occur most often in patients who are immunosuppressed. Common risk factors include diabetes, immunosuppressive medications, and chronic hematologic disorders such as leukemia or lymphoma. The species most often implicated are Histoplasma capsulatum, Aspergillus fumigatus, Candida albicans, and Penicillium species. These lesions most commonly result from colonization of a preexisting aneurysm or infection of a damaged artery. Radiologic appearance may be identical to that which results from a bacterial arterial infection. The distinction is noted in the pathologic evaluation of the affected arterial wall, which demonstrates acute and chronic adventitial inflammatory changes. Secondary bacterial infections may be present, and cultures may be positive in a minority of these patients. There appears to be a predilection toward carotid and femoral arteries; however, the aorta may also be involved. The erosion is thought to be facilitated by the indurated, atherosclerotic artery pressing against a tethered portion of bowel. In their 1951 review of a series of 16,633 autopsies, Hirst and Affeldt126 reported the incidence of this type of fistula to be 0. In this presentation, the initial hemorrhage may abate then later resume in a more prolonged and dramatic manner. The prerequisites of this approach are the absence of purulence at the fistula site, a small defect in the duodenum, and a relatively healthy patient. This is followed, in order of frequency by Streptococcus species, Bacteroides species, Arizona, hinshawii, E. Brown and colleagues128 suggested that the reason for this change is antibiotic selective pressure leading to bacterial adaptation. The majority of arterial infections during the preantibiotic era were oslerian mycotic aneurysms; that is, they were related to bacterial endocarditis. The bacteriology of arterial infections during this period therefore was similar to that of endocarditis. Stengal and Wolferth129 in the 1920s and Revell119 in the 1940s reported that the predominant organisms were nonhemolytic streptococci, staphylococci, and pneumococci. The declining incidence of rheumatic fever and the adoption of early appropriate antibiotic treatment have resulted in a significant decrease, in bacterial endocarditis. This in turn has resulted in a decline in the incidence of oslerian mycotic aneurysms in recent decades. This may be due, in part, to the increasing age of the population and the simultaneous increase in the prevalence of atherosclerosis. The bacteriology of these arterial infections is different from that of oslerian mycotic aneurysms. The microorganisms most commonly associated with microbial arteritis are Salmonella species, Staphylococcus species, and E. Salmonella species, in particular, have a striking propensity for invading diseased (atherosclerotic) aortas. In selected series, the involvement of Salmonella species has been reported to be as high as 50%. The most virulent species, Salmonella choleraesuis and Salmonella typhimurium, account for more than 60% of the reported cases of Salmonella arteritis. Among the latter, Bacteroides fragilis has been reported in association with supraceliac aortic aneurysms.

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Repeat injections may be required heart attack jaw pain order coumadin 2 mg, but the ultimate success rate may be as high as 99% blood pressure cuff amazon 2 mg coumadin buy with amex. In this scenario arteria radial discount coumadin 1 mg on line, a stent graft can be placed over the site of arterial injury without any threat to the profunda femoris origin or common femoral artery prehypertension 134 coumadin 2 mg buy cheap. On rare occasion heart attack vegas order coumadin 5 mg free shipping, especially when the presentation is delayed or there is suspicion of an infectious process, access to the retroperitoneum may be necessary to achieve proximal control of lowerextremity inflow at the level of the iliac vessels. Regardless, exposure should be obtained proximal and distal to the puncture site, and digital control of the bleeding can be obtained. It is essential to check the back wall of the artery to be sure there is not another source of bleeding. Rarely, when significant injury is present in an atherosclerotic artery, a patch may be required to avoid compromising the lumen. Pediatric Vascular Trauma Vascular trauma in the pediatric population is uncommon, occurring in only 0. Although less frequent than in adults, penetrating trauma is responsible for a slight majority of pediatric vascular injuries. Injury to the carotid artery is exceedingly rare but can have devastating morbidity and mortality, if not recognized and managed promptly. Amputations are usually reserved for severely mangled extremities; all attempts should be made for limb salvage. Overall, pediatric patients have an improved adjusted mortality when compared with adults. Western Trauma Association critical decisions in trauma: screening for and treatment of blunt cerebrovascular injuries. Blunt cerebrovascular injuries: redefining screening criteria in the era of noninvasive diagnosis. Blunt cerebrovascular injury practice management guidelines: the Eastern Association for the Surgery of Trauma. Diagnosis and management of traumatic pseudoaneurysm of the carotid artery: case report and review of the literature. Endovascular stenting for the treatment of traumatic internal carotid injuries: expanding experience. Practice management guidelines for management of hemothorax and occult pneumothorax. Western Trauma Association critical decisions in trauma: resuscitative thoracotomy. Screening for blunt cardiac injury: an Eastern Association for the Surgery of Trauma practice management guideline. Trends and outcomes of endovascular therapy in the management of civilian vascular injuries. Endovascular repair compared with operative repair of traumatic rupture of the thoracic aorta: a nonsystematic review and a plea for traumaspecific reporting guidelines. A clinical series of resuscitative endovascular balloon occlusion of the aorta for hemorrhage control and resuscitation. Patient factors and operating room resuscitation predict mortality in traumatic abdominal aortic injury: a 20-year analysis. Western Trauma Association Critical Decisions in Trauma: management of abdominal vascular trauma. Analysis of diagnostic angiography and angioembolization in the acute management of renal trauma using a national data set. Characterization and outcomes of iliac vessel injury in the 21st century: a review of the National Trauma Data Bank. Associated venous injury significantly complicates presentation, management, and outcomes of axillosubclavian arterial trauma. Limb outcome and mortality in lower and upper extremity arterial injury: a comparison using the National Trauma Data Bank. Limb salvage and outcomes among patients with traumatic popliteal vascular injury: an analysis of the National Trauma Data Bank. Early fasciotomy in patients with extremity vascular injury is associated with decreased risk of adverse limb outcomes: a review of the National Trauma Data Bank. Iatrogenic femoral artery pseudoaneurysms-a review of current methods of diagnosis and treatment. Incidence and clinical outcome of iatrogenic femoral arteriovenous fistulas: implications for risk stratification and treatment. Traumatic extremity arterial injury in children: epidemiology, diagnostics, treatment and prognostic value of Mangled Extremity Severity Score. Observation and surgery are associated with low risk of amputation for blunt brachial artery injury in pediatric patients. Extracranial traumatic carotid artery dissections in children: a review of current diagnosis and treatment options. This article will focus on the anatomy, pathophysiology, and management of the more commonly encountered vascular compression syndromes, namely, vascular thoracic outlet syndromes, median arcuate ligament syndrome, nutcracker syndrome, May-Thurner syndrome, popliteal entrapment syndrome, and cystic adventitial disease. Keywords vascular compression; thoracic outlet syndrome; nutcracker; popliteal entrapment Vascular compression syndromes are uncommon conditions caused by narrowing or occlusion of vascular structures by adjacent tissues in disparate regions of the body. Neurogenic thoracic outlet is the most common (90%), with venous (8%), and arterial (2%) being far less common. If left untreated, they can potentially result in chronic pain syndromes, long-term restrictions to limb use, limb-threatening complications, and significant disability in otherwise relatively young, active, healthy people. Venous thoracic outlet syndrome Clinical Presentation Paget-Schroetter syndrome (axillosubclavian vein thrombosis or "effort" thrombosis) usually presents with acute unilateral upper extremity swelling in a previously healthy patient, which often prompts urgent medical care. Archetypically, the patient is a young athlete or worker with a component to his or her sport or job that requires prolonged or repetitive stressful positioning of the arm, such as baseball pitchers, swimmers, weight lifters, volleyball players, and mechanics. Physical examination may reveal the presence of dilated collateral veins around the shoulder and upper arm. If the condition is ignored, the symptoms may resolve when at rest but can either persist or recur with use of the arm, particularly in a stressed (abducted, externally rotated) position. The collateral channels that develop to allow the swelling to abate when at rest are rarely adequate to accommodate the increased venous return that occurs with activity. Comprehensive surgical management of the competitive athlete with effort thrombosis of the subclavian vein [Paget-Schroetter syndrome]. They can also identify enlarged collateral veins and the chronicity of any thrombus present. Diagnosis and treatment of effort-induced thrombosis of axillary subclavian vein due to venous thoracic outlet syndrome. This provides complete anatomical information regarding the site and extent of thrombosis, allows definitive evaluation of the collateral venous pathways, and allows use of thrombolytic therapy. Catheterbased upper extremity venography is the most practical, efficient, and costeffective approach to evaluating the patient with suspected subclavian vein effort thrombosis. Pharmacomechanical thrombolysis can reduce the clot burden rapidly, usually within a 1- to 2-hour session. Balloon angioplasty does not provide a durable benefit and placement of stents is contraindicated due to complications of frequent stent fracture. In patients with a satisfactory result after thrombolysis, surgical treatment is recommended within 4 to 6 weeks after presentation to avoid recurrent thrombosis of the subclavian vein. This time period does allow for some resolution of perivenous inflammation caused by the thrombotic event. Surgery can be safely performed sooner if the patient continues to have marked subclavian vein stenosis or occlusion after lysis. Using the supraclavicular incision, resection of the anterior and middle scalene muscles is completed and the posterior first rib is transected at the transverse process. Using the infraclavicular incision, the rib is transected at the edge of the sternum anteriorly and removed. This facilitates a complete external venolysis from the axillary vein to the junction of the subclavian, internal jugular, and innominate veins via the two incisions. Frequently, external venolysis is sufficient if complete resection of fibrous scar tissue allows the vein to resume its normal diameter and a widely patent subclavian vein with no significant collaterals is seen on venography. Residual vein stenosis or occlusion can be repaired with patch angioplasty or interposition vein bypass. These have been shown to have disadvantages, chiefly relating to the lack of exposure of the vein for a complete venolysis and comprehensive treatment. However, satisfactory clinical outcomes were greater with the paraclavicular approach, and the likelihood of remaining on long-term anticoagulation is markedly lower, at less than 5%. Compression of the subclavian artery over time leads to progressive inflammation and scarring. This can be associated with poststenotic dilatation, which may progress to aneurysmal degeneration. Patients can present with intermittent claudication or rest pain of the upper extremity. Some patients are asymptomatic but have dilation of the subclavian artery noted incidentally during unrelated imaging investigations. When the cervical rib projects from the transverse process onto the first rib, it displaces the brachial plexus and subclavian artery forward. Another common bony anomaly is the presence of an elongated C7 transverse process that acts in a similar fashion. Fibrous bands, if present, from the C7 transverse process to the first rib, can exacerbate compression. Noninvasive vascular studies can be used to confirm a clinical impression of arterial insufficiency. Treatment Patients undergo thoracic outlet decompression from a supraclavicular approach. The subsequent management modalities include observation, endarterectomy and patch, or bypass with either vein or Dacron. In the largest series of 40 patients with a follow-up of nearly 5 years, 92% continued to have a patent subclavian artery. Chronic symptoms persisted in 15% of patients; these patients had long-standing ischemia prior to intervention. Overall, surgical management of this rare disease entity results in satisfactory outcomes when patients are referred promptly after symptoms ensue. Axillary artery compression syndrome Axillary artery compression syndrome is a markedly less frequently encountered syndrome. These include pitchers, handball players, kayakers, tennis players, and volleyball players. Typical presentation involves digital ischemia due to embolization but can have more subtle findings such as early fatigue of throwing arm or loss of velocity. Repetitive positional compression of the axillary artery and its branches can lead to intimal hyperplasia, aneurysm formation with mural thrombus, and branch vessel aneurysm. Revascularization can be accomplished via an interposition saphenous vein graft, a patch angioplasty, or an aneurysm excision alone. It is caused by the compression of the celiac artery by the diaphragmatic crura and the fibrous arch that unites the crura, the median arcuate ligament. On physical exam, epigastric tenderness and a bruit that is amplified by expiration can be present. It is more prevalent in women (ratio 4:1) aged 30 to 50 years and in those with a thin body habitus. Pathophysiology the celiac artery is the first abdominal aortic branch that takes off at a 90-degree angle with the aorta. Due to this configuration, it is susceptible to compression by the diaphragmatic crura during thoracic motion, especially with expiration. In most patients, the stenosis or occlusion caused by the compression is asymptomatic and frequently found incidentally. Any structural or functional abnormality of the upper abdomen identified should be evaluated and treated first. If other causes of the symptoms have been excluded, celiac artery stenosis or occlusion must be confirmed. Demonstration of variation of the stenosis with respiration is necessary to distinguish from more common causes of celiac artery stenosis such as atherosclerosis. However, compression of the celiac axis during expiration can be demonstrated in asymptomatic individuals and further underscores the challenge of establishing this diagnosis. Treatment the treatment paradigm requires division of the median arcuate ligament and release of all fibrotic tissue surrounding the celiac artery with revascularization of the celiac artery as necessary. However, uncontrolled bleeding, potential incomplete release, and injury to aorta due to difficult dissection are potential disadvantages. Robotic surgery and retroperitoneal endoscopic release have also been described for this step. Some authors advocate decompression alone with minimally invasive techniques, whereas others decompress and revascularize all or most patients immediately via an open approach. Endovascular embolization of this entity is preferred over open surgery because these aneurysms are very difficult to locate and expose surgically. One report documented that, in a series of six patients with long-term follow-up, all patients would have the surgery again. Contemporary diagnosis and management strategies for this syndrome remain in evolution, but release of median arcuate ligament with or without celiac artery revascularization appears to adequately treat most patients effectively. When found radiographically incidentally, it is referred to as nutcracker phenomenon. The compression results in venous hypertension of the left renal vein and its branches, which in turn causes the symptomatology of this syndrome. Symptoms can include hematuria (microscopic and macroscopic), orthostatic proteinuria, left flank pain, abdominal pain, left lower extremity varicose veins, left varicocele in males, and pelvic congestion syndrome in females. Retroaortic location of the left renal vein is also associated with nutcracker syndrome, with the left renal vein being entrapped between the aorta and the adjacent vertebral body.

Efforts to attenuate the systemic inflammation associated with reperfusion have also focused on modulating the molecular mediators of end-organ injury pulse pressure uptodate coumadin 5 mg on-line. T-cell sequestration agents have been shown to decrease systemic inflammation and to reduce transcription of injury-associated target genes in multiple end-organs heart attack manhattan clique remix 2 mg coumadin purchase overnight delivery. This modulation could preserve vascular homeostasis and integrity fetal arrhythmia 33 weeks coumadin 1 mg buy line, and facilitate perfusion of the ischemic limb arrhythmia course certification order discount coumadin on-line. Systemic antithrombotic therapy may be appropriate in patients with a cardioembolic source of arterial embolism blood pressure goes up and down coumadin 1 mg order mastercard. Patients who suffered acute limb ischemia due to stent or graft failure may require the addition of an antithrombotic agent to their antiplatelet therapy. Vorapaxar, an oral thrombin receptor antagonist, has been shown to reduce the incidence of acute limb ischemia. Increased risk of bleeding associated with vorapaxar therapy has hindered its acceptance in clinical practice. After a follow-up of 3 years, patients treated with aspirin and ticagrelor had a 51% lower rate of acute limb ischemia and revascularization for ischemia compared to patients treated with aspirin alone. After a median follow up of 21 months, the risk of developing acute limb ischemia was 44% lower in the low-dose rivaroxaban plus aspirin group and 43% lower in the rivaroxaban alone group compared to the aspirin alone group. Unlike the combination of rivaroxaban and aspirin, rivaroxaban monotherapy did not reduce the rate of major adverse cardiovascular events compared to aspirin monotherapy. A national and single institutional experience in the contemporary treatment of acute lower extremity ischemia. Weak links in the early chain of care of acute lower limb ischaemia in terms of recognition and emergency management. Acute ischaemia of the upper limb compared with acute lower limb ischaemia; a 5-year review. Acute limb ischemia due to arterial embolism or thrombosis: influence of limb ischemia versus pre-existing cardiac disease on postoperative mortality rate. Upper extremity ischemia from subclavian artery aneurysm caused by bony abnormalities of the thoracic outlet. Major peripheral arterial occlusion due to malignant tumor embolism: histologic recognition and surgical management. Selective conservative and routine early operative treatment in acute limb ischaemia. Clinical outcome of acute leg ischaemia due to thrombosed popliteal artery aneurysm: systematic review of 895 cases. The pathophysiology of skeletal muscle ischemia and the reperfusion syndrome: a review. Pathophysiology, clinical manifestations, and prevention of ischemia-reperfusion injury. Neutrophil-mediated microvascular dysfunction in postischemic canine skeletal muscle. Neutrophils accumulate and contribute to skeletal muscle dysfunction after ischemia-reperfusion. Role of leukocytes in reperfusion injury of skeletal muscle after partial ischemia. Role for tumor necrosis factor as mediator of lung injury following lower torso ischemia. Lower limb ischemia-reperfusion injury triggers a systemic inflammatory response and multiple organ dysfunction. Interleukin-1 and thromboxane release after skeletal muscle ischemia and reperfusion. Actions of tumor necrosis factor on cultured vascular endothelial cells: morphologic modulation, growth inhibition, and cytotoxicity. Contemporary management of acute limb ischemia: factors associated with amputation and in-hospital mortality. Management of acute lower extremity arterial ischemia due to embolism and thrombosis. Risk factors for long-term mortality and amputation after open and endovascular treatment of acute limb ischemia. Routine versus selective use of intraoperative angiography during thromboembolectomy for acute lower limb ischemia: analysis of outcomes. Early outcomes following endovascular, open surgical, and hybrid revascularization for lower extremity acute limb ischemia. Trends in the incidence, treatment, and outcomes of acute lower extremity ischemia in the United States Medicare population. Acute lower limb ischemia: failure of anticoagulant treatment to improve onemonth results of arterial thromboembolectomy. Plasma creatine kinase indicates major amputation or limb preservation in acute lower limb ischemia. The intravenous infusion of the streptococcal fibrinolytic principle (streptokinase) into patients. Randomized trial of intraarterial recombinant tissue plasminogen activator, intravenous recombinant tissue plasminogen activator and intraarterial streptokinase in peripheral arterial thrombolysis. Quality improvement guidelines for percutaneous catheter-directed intraarterial thrombolysis and mechanical thrombectomy for acute lower-limb ischemia. Acute peripheral arterial occlusion: predictors of success in catheter-directed thrombolytic therapy. Comparison of tissue plasminogen activator and urokinase in the local infiltration thrombolysis of peripheral arterial occlusions. Safety and efficacy of reteplase for the treatment of acute arterial occlusion: complexity of underlying lesion predicts outcome. Initial experience with the combination of reteplase and abciximab for thrombolytic therapy in peripheral arterial occlusive disease: a pilot study. Safety and effectiveness of adjunctive intraarterial abciximab in the management of acute limb ischemia. Thrombolysis of peripheral arterial and graft occlusions: improved results using high-dose urokinase. Novel simultaneous combination chemical thrombolysis/rheolytic thrombectomy therapy for acute critical limb ischemia: the power-pulse spray technique. Mechanical thromboembolectomy in acute embolic peripheral arterial occlusions with use of the AngioJet Rapid Thrombectomy System. Rheolytic thrombectomy in the management of acute and subacute limbthreatening ischemia. Rheolytic thrombectomy in the management of limb ischemia: 30-day results from a multicenter registry. Rapid thrombectomy with a hydrodynamic catheter: results from a prospective, multicenter trial. Rheolytic thrombectomy in the treatment of acute limb-threatening ischemia: immediate results and six-month follow-up of the multicenter AngioJet registry. Rheolytic hydrodynamic thrombectomy for percutaneous treatment of acutely occluded infra-aortic native arteries and bypass grafts: midterm follow-up results. Clinical and economic evaluation of the trellis thrombectomy device for arterial occlusions: preliminary analysis. Mechanical thrombectomy using the Rotarex catheter-safe and effective method in the treatment of peripheral arterial thromboembolic occlusions. Acute embolic occlusions of the infrainguinal arteries: percutaneous aspiration embolectomy in 102 patients. Percutaneous catheter thrombus aspiration for acute or subacute arterial occlusion of the legs: how much thrombolysis is needed. Technical results of vacuum-assisted thrombectomy for arterial clot removal in patients with acute limb ischemia. High intensity, low frequency catheter-delivered ultrasound dissolution of occlusive coronary artery thrombi: an in vitro and in vivo study. Ultrasound accelerates transport of recombinant tissue plasminogen activator into clots. Treatment of acute femoropopliteal bypass graft occlusion: comparison of mechanical rotational thrombectomy with ultrasound-enhanced lysis. Initial results of catheter-directed ultrasound-accelerated thrombolysis for thromboembolic obstructions of the aortofemoral arteries: a feasibility study. Ultrasoundaccelerated versus standard catheter-directed thrombolysis in 102 patients with acute and subacute limb ischemia. Intraoperative angiography in the immediate assessment of arterial reconstruction. Acute ischemia of the upper extremity: long-term results following thrombembolectomy with the Fogarty catheter. Local thrombolytic infusion in arterial ischemia of the upper limb: mid-term results. Predictive factors for post-ischemic compartment syndrome in non-traumatic acute limb ischemia in a lower extremity. Acute compartment syndromes: diagnosis and treatment with the aid of the wick catheter. Does open fasciotomy contribute to morbidity and mortality after acute lower extremity ischemia and revascularization. Acute compartment syndrome of the lower leg: retrospective study on prevalence, technique, and outcome of fasciotomies. Prophylactic fasciotomy of the legs following acute arterial occlusion procedures. Intramuscular pressure after revascularization of the popliteal artery in severe ischaemia. Muscular compartment pressure following reconstructive arterial surgery of the lower limbs. Hypothermia and controlled reperfusion: two non-pharmacologic methods which diminish ischemia-reperfusion injury in skeletal muscle. Basic control of reperfusion effectively protects against reperfusion injury in a realistic rodent model of acute limb ischemia. Sustained benefit of temporary limited reperfusion in skeletal muscle following ischemia. Local hypothermia during early reperfusion protects skeletal muscle from ischemia-reperfusion injury. Controlled reperfusion using a simplified perfusion system preserves function after acute and persistent limb ischemia: a preliminary study. Caffeine mitigates lung inflammation induced by ischemia-reperfusion of lower limbs in rats. Rivaroxaban with or without aspirin in patients with stable peripheral or carotid artery disease: an international, randomised, double-blind, placebo-controlled trial. Shepherd Abstract Atheroembolism is a rare systemic disorder occurring when tiny fragments of an atherosclerotic plaque (in particular, cholesterol crystals) break off from a proximal artery and travel distally in the circulation. The consequence of this event is microvascular obstruction in small arteries, resulting in tissue ischemia. This results in clinically recognizable entities including livedo reticularis, the blue toe syndrome, and acute and chronic kidney failure. Atheroembolism can occur spontaneously but more commonly follows an invasive angiographic or endovascular procedure. Prompt diagnosis is imperative, and a high index of clinical suspicion is necessary as atheroembolism may mimic a number of other disorders, leading to potential misdiagnosis. Confirmative diagnosis requires histological confirmation of cholesterol crystals in a biopsy of muscle, skin, or affected organ. Keywords atheroembolism; atheromatous embolization; cholesterol crystal embolization; aortic plaque; aortic arch atheroma and stroke; mobile atheroma; atheroembolic renal disease; livedo reticularis; blue (purple) toe syndrome; lower extremity ischemia; transient ischemic attack; Hollenhorst plaque; urinary eosinophils Atheroembolism is a rare but serious disorder with significant morbidity from stroke, renal failure, and limb loss. It can originate from atherosclerotic or aneurysmal disease and involve single or multiple sites. There is no specific laboratory test that can reliably distinguish cholesterol embolization from other disorders. A definitive diagnosis can only be made with biopsy of involved tissue and histological examination. A high index of clinical suspicion is necessary because atheroembolism may mimic a number of other disorders, leading to potential misdiagnosis. The focus of this chapter will be review of pathophysiology, precipitating factors, clinical syndromes, and management of atheroembolic disease. Prognosis is determined by the extent of systemic involvement and risk of recurrent episodes. Atheroembolism occurs when tiny fragments of an atherosclerotic plaque (in particular, cholesterol crystals) break off from a proximal artery and travel distally in the circulation, ending up in small arteries downstream from the origin. The abdominal aorta is the most common origin for atheroembolism to the abdominal organs and lower extremities, but any artery with atheromatous disease may be a potential embolic source. End-organ targets include the brain, eye, heart, kidney, gastrointestinal tract, fingers, toes, and skin. Atheroembolism is a much different disease and can be more difficult to diagnose and manage. Thromboembolism occurs when a section of thrombus breaks off from a proximal site, such as the heart, and occludes downstream vessels. Thromboembolism can be diagnosed by computed tomography, magnetic resonance, or invasive imaging, as it causes obstruction of large proximal vessels. By contrast, an atheroembolic event is a shower of tiny particles originating from atherosclerotic plaque, causing very distal end organ embolization and tissue ischemia. Acute and chronic kidney failure can result from aortic or renal artery atheroembolism. Atheroemboli can also travel to the mesenteric arteries, causing intestinal necrosis, or to the splenic, hepatic, or pancreatic arteries, causing localized infarction. Transient ischemic episodes and stroke may result from atheromatous disease of the aortic arch, internal carotid, or vertebral arteries.

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