[Posterior laceration of the abdominal aorta on vertebral fracture]. / Lacération postérieure de l'aorte abdominale sur fracture vertébrale.

Abdominal aortic lacerations are very rare in closed trauma and are usually caused by high energy trauma. Aortic injuries should be assessed as a priority as they present an immediate life-threatening risk in the event of major haemorrhage. However, the clinical presentations are highly variable and often misleading. We -present a case of traumatic blunt abdominal aortic laceration following a fall down the stairs. The laceration involved the posterior part of the abdominal aorta secondary to a lumbar fracture with L1-L2 disc tear.

Les lacérations de l'aorte abdominale sont très rares dans les traumatismes fermés et sont généralement causées par des traumatismes à haute énergie. Les lésions aortiques doivent être évaluées en priorité car elles présentent un risque vital immédiat en cas d'hémorragie majeure. Cependant, les présentations cliniques sont très variables et souvent trompeuses. Nous présentons un cas de lacération aortique abdominale traumatique suite à une chute dans les escaliers. La lacération intéresse la partie postérieure de l'aorte abdominale sur une fracture lombaire avec déchirure du disque L1-L2.

A single-center experience on the management of pediatric blunt aortic injury.

OBJECTIVE: Blunt abdominal aortic injury in children is a rare clinical entity with which most vascular surgeons have minimal experience. The evidence for management recommendations is limited. We have reported a single institution's experience in the care of pediatric abdominal aortic injuries. METHODS: We performed a retrospective review of consecutive pediatric patients who had been diagnosed with blunt traumatic abdominal aortic injury at our institution from 2008 to 2019. RESULTS: A total of 16 pediatric patients (50% male) were identified. They ranged in age from 4 to 17 years. All had been involved in motor vehicle collisions and had been restrained passengers with a seatbelt in use. Five patients (31%) were hypotensive en route or on arrival. Seven patients (44%) had been transferred from another hospital. The median injury severity score was 34 (interquartile range, 19-35). The infrarenal aortic injuries were stratified using the aortic injury grading classification (five, two, seven, and two with grade 1, 2, 3, and 4, respectively). Concurrent nonaortic injuries included solid organ (63%; n = 10), hollow viscus (88%; n = 14), brain (25%; n = 4), hemothorax or pneumothorax (25%; n = 4), spine fractures (81%; n = 13), and nonspine fractures (75%; n = 12). Of the 16 patients, 9 (56%) had required aortic repair. Three had required immediate revascularization for distal ischemia. The remaining six patients (38%) had undergone delayed repair, with a median interval to repair of 52 days (range, 2-916 days). One half of the delayed repairs were performed during the index hospitalization. On repeat axial imaging, the three patients who had undergone delayed repair were found to have enlarging pseudoaneurysms or flow-limiting dissections and had subsequently undergone repair during the index hospitalization. Only one patient had undergone endovascular repair. No deaths occurred, and the median follow-up was 7 months (interquartile range, 3-28 months) for our study population. All postoperative patients demonstrated stable imaging findings without requiring further intervention. Seven patients, whose injury grades had ranged from 1 to 3, were observed. Their repeat imaging studies demonstrated either stability or resolution of their aortic injury. However, one half of the patients had been lost to follow-up after discharge or after their first postoperative clinic visit. CONCLUSIONS: Delayed aortic intervention can be safely performed for most pediatric patients with blunt abdominal aortic injuries with preserved distal perfusion to the lower extremities. This finding suggests that transfer to a tertiary center with vascular expertise is a safe and feasible management strategy. However, the progression of aortic injuries was seen as early as within 48 hours and as late as 30 months after injury, underscoring the importance of long-term surveillance. However, in our cohort, 50% of the children were lost to follow-up, highlighting the need for a more structured surveillance strategy.

Assessing potential for aortoiliac vascular injury from venoarterial extracorporeal membrane oxygenation cannulae: An in vitro particle image velocimetry study.

Limb ischemia is a major complication associated with peripheral venoarterial extracorporeal membrane oxygenation (VA-ECMO). The high velocity jet from arterial cannulae can cause "sandblasting" injuries to the arterial endothelium, with the potential risk of distal embolization and end organ damage. The aim of this study was to identify, for a range of clinically relevant VA-ECMO cannulae and flow rates, any regions of peak flow velocity on the aortic wall which may predispose to vascular injury, and any regions of low-velocity flow which may predispose to thrombus formation. A silicone model of the aortic and iliac vessels was sourced and the right external iliac artery was cannulated. Cannulae ranged from 15 to 21 Fr in size. Simulated steady state ECMO flow rates were instituted using a magnetically levitated pump (CentriMag pump). Adaptive particle image velocimetry was performed for each cannula at 3, 3.5, 4, and 4.5 L/min. For all cannulae, in both horizontal and vertical side hole orientations, the peak velocity on the aortic wall ranged from 0.3 to 0.45 m/s, and the regions of lowest velocity flow were 0.05 m/s. The magnitude of peak velocity flow on the aortic wall was not different between a single pair versus multiple pairs of side holes. Maximum velocity flow on the aortic wall occurred earlier at a lower pump flow rate in the vertical orientation of distal side holes compared to a horizontal position. The presence of multiple paired side holes was associated with fewer low-velocity flow regions, and some retrograde flow, in the distal abdominal aorta compared to cannulae with a single pair of side holes. From this in vitro visualization study, the selection of a cannula design with multiple versus single pairs of side holes did not change the magnitude of peak velocity flow delivered to the vessel wall. Cannulae with multiple side holes were associated with fewer regions of low-velocity flow in the distal abdominal aorta. Further in vivo studies, and ideally clinical data would be required to assess any correlation of peak velocity flows with incidence of vascular injury, and any low-velocity flow regions with incidence of thrombosis.

Cholesterol embolization and arterial occlusion from the Heimlich maneuver.

The Heimlich maneuver is a lifesaving bystander intervention to assist an individual with airway obstruction however, cholesterol embolization syndrome is a rare, but serious potential complication of the Heimlich maneuver. We present the case of the 56-year-old female presenting to the emergency department with acute right foot pain following performance of the Heimlich maneuver who was found to have distal arterial occlusion resulting from cholesterol embolization syndrome. The patient underwent right popliteal artery exploration, right popliteal and tibial thrombectomy, and popliteal patch angioplasty resulting in restoration of blood flow to her right foot.

Predictors of blunt abdominal aortic injury in trauma patients and mortality analysis.

OBJECTIVE: Blunt abdominal aortic injury (BAAI) occurs in less than 0.1% of blunt traumas. A previous multi-institutional study found an associated mortality rate of 39%. We sought to identify risk factors for BAAI and risk factors for mortality in patients with BAAI using a large national database. We hypothesized that an Injury Severity Score of 25 or greater, and thoracic trauma would both increase the risk of mortality in patients with BAAI. METHODS: The Trauma Quality Improvement Program (2010-2016) was queried for individuals with blunt trauma. Patients with and without BAAI were compared. Covariates were included in a multivariable logistic regression model to determine mechanisms of injury, examination findings, and concomitant injuries associated with increased risk for BAAI. An additional multivariable analysis was performed for mortality in patients with BAAI. RESULTS: From 1,056,633 blunt trauma admissions, 1012 (0.1%) had BAAI. The most common mechanism of injury was motor vehicle accident (MVA; 57.5%). More than one-half the patients had at least one rib fracture (54.0%), or a spine fracture (53.9%), whereas 20.8% had hypotension on admission and 7.8% had a trunk abrasion. The average length of stay was 13.4 days and 24.6% required laparotomy, with 6.6% receiving an endovascular repair and 2.9% an open repair. The risk of death in those treated with endovascular vs open repair was similar (P = .28). On multivariable analysis, MVA was the mechanism associated with the highest risk of BAAI (odds ratio [OR], 4.68; 95% confidence interval [CI], 3.87-5.65; P < .001) followed by pedestrian struck (OR, 4.54; 95% CI, 3.47-5.92; P < .001). Other factors associated with BAAI included hypotension on admission (OR, 3.87; 95% CI, 3.21-4.66; P < .001), hemopneumothorax (OR, 3.67; 95% CI, 1.16-11.58; P < .001), abrasion to the trunk (OR, 1.49; 95% CI, 1.15-1.94; P = .003), and rib fracture (OR, 1.46; 95% CI, 1.25-1.70; P < .001). The overall mortality rate was 28.0%. Of the variables examined, the strongest risk factor associated with mortality in patients with BAAI was hemopneumothorax (OR, 12.49; 95% CI, 1.25-124.84; P = .03) followed by inferior vena cava (IVC) injury (OR, 12.05; 95% CI, 2.80-51.80; P < .001). CONCLUSIONS: In the largest nationwide series to date, BAAI continues to have a high mortality rate with hemopneumothorax and IVC injury associated with the highest risk for mortality. The mechanism most strongly associated with BAAI is MVA followed by pedestrian struck. Other risk factors for BAAI include rib fracture and trunk abrasion. Providers must maintain a high suspicion of injury for BAAI when these mechanisms of injury, physical examination or imaging findings are encountered.

Clinical aspects and present challenges of the seat belt aorta.

OBJECTIVE: Seat belt aorta is rare and difficult to manage. The lack of data and follow-up increases the complexity of treating such patients. We aimed to create a decision algorithm by reviewing our current experience and analyzing the presentation and management of our patients. METHODS: We performed a descriptive case series based on retrospective analysis of all consecutive patients admitted with the diagnosis of seat belt aorta from 2008 to 2018. Seat belt aorta was defined as any blunt abdominal aortic lesion resulting from a seat belt compression mechanism after a car accident. RESULTS: Nine consecutive patients were admitted with the diagnosis of seat belt aorta, all of whom developed lesions in the infrarenal aorta. Eight patients were assessed in the acute phase and one patient presented with late-onset symptoms. Associated injuries were present in all acute patients, and seat belt sign and small bowel injury were present in 88%. One patient presented with a small intimal tear and was treated conservatively. All other patients diagnosed with large intimal flaps (seven patients) and pseudoaneurysm (one patient) underwent open repair in five cases and endovascular repair in three cases. In-hospital mortality for the acute cases was 38%, with no mortality seen during follow-up. Two patients submitted to endovascular repair required reinterventions. CONCLUSIONS: Seat belt aorta is a deadly condition, frequently associated with blunt thoracoabdominal trauma with concomitant injuries; the presence of a seat belt sign or lower limb ischemia must lead to a high diagnostic suspicion. Management must take into account the other concomitant injuries. Follow-up is crucial as most patients are young; they may develop complications and subsequently require further intervention.

Aortic Transection after Blunt Abdominal Trauma in a Child.

Abdominal aortic injury secondary to blunt abdominal aortic trauma (BAAI) is rare in children but frequently occurs in association with other injuries, including bowel injury and vertebral fracture. We present a case of a 14-year-old boy who sustained a partial transection of the infrarenal aorta with a lumbar chance fracture and small bowel injury after a motor vehicle accident. Repair was performed with bowel resection followed by Dacron graft interposition. We reviewed the literature on BAAI in children with a focus on the method of repair of these injuries.

Management of Seat Belt-type Blunt Abdominal Aortic Trauma and Associated Injuries in Pediatric Patients.

BACKGROUND: "Seat belt-type" pediatric abdominal aortic trauma is uncommon but potentially lethal. During high speed motor vehicle collisions (MVCs), seat or lap belt restraints may concentrate forces in a band-like pattern across the abdomen, resulting in the triad of hollow viscus perforation, spine fracture, and aortoiliac injury. We report 4 cases of pediatric seat belt-type aortic trauma and review management strategies for the aortic disruption and the associated constellation of injuries. METHODS: -approved, retrospective review of all pediatric patients requiring surgical intervention for seat belt-type constellation of abdominal aortic/iliac and associated injuries over a 5-year period. Blunt thoracic aortic injuries were excluded. RESULTS: We identified 4 patients, ranging from 2 to 17 years of age, who required surgical correction of seat belt-type aortoiliac trauma and associated injuries: 3 abdominal aortas and 1 left common iliac artery. The majority (3/4 patients) were hemodynamically unstable at emergency room presentation, and all underwent computed tomography angiography of the chest/abdomen/pelvis during initial resuscitation. Injuries of the suprarenal and proximal infrarenal aorta were accompanied by unilateral renal artery avulsion requiring nephrectomy. Presumed or proven spinal instability mandated supine positioning and midline laparotomy, with medial visceral rotation utilized for proximal injuries. Aortoiliac injuries requiring repair were accompanied by significant distal intraluminal prolapse of dissected intima, with varying degrees of obstruction. Conduit selection was dictated by the presence of enteric contamination and the rapid availability of an autologous conduit. The sole neurologic deficit was irreparable at presentation. CONCLUSIONS: Seat belt aortoiliac injuries in pediatric patients require prompt multidisciplinary evaluation. Evidence of contained aortoiliac transection, major branch vessel avulsion, and bowel perforation mandates immediate exploration, which generally precedes spinal interventions. Lesser degrees of aortoiliac injuries have been managed with surveillance, but long-term follow-up is needed to fully validate this approach.

Point-of Care Ultrasonographically Guided Proximal External Aortic Compression in the Emergency Department.

In cases of severe subdiaphragmatic vascular trauma, only in extremis interventions such as emergency thoracotomy with aortic cross clamping or resuscitative endovascular balloon occlusion of the aorta are available for temporization until definitive care. This case report proposes a noninvasive approach consisting of localizing the proximal aorta with ultrasonographic guidance and applying a compressive force to occlude the aorta and limit distal flow. Using point-of-care ultrasonography allows precise compression, continuous monitoring of its efficacy, and early detection of return of spontaneous circulation in arrest patients. We present the case of a patient who sustained a gunshot wound causing a left iliac artery injury and subsequent cardiac arrest while he was on route to the hospital. Point-of-care ultrasonographically guided proximal external aortic compression was attempted and return of spontaneous circulation was achieved and maintained, allowing transfer of the patient to the operating room. This single-case report suggests that point-of-care ultrasonographically guided proximal external aortic compression could be used as a bridge to definitive care or to more advanced techniques such as resuscitative endovascular balloon occlusion of the aorta and emergency department thoracotomy with aortic cross clamping.

The methods for inserting lumbar bicortical pedicle screws from the anatomical perspective of the prevertebral great vessels.

BACKGROUND: At present, bicortical pedicle screws (BPSs) are not used clinically because they carry the potential risk of damaging the prevertebral great vessels (PGVs). The authors observed the anatomical relationship between the PGVs and simulated BPSs at different transverse screw angles (TSAs), exploring the insertion method of the BPS. METHODS: Computed tomography angiography (CTA) images from 65 adults were collected. A total of 4-5 TSAs of the BPSs were simulated on the left and right sides of L1-L5 (L1-L3: 0°, 5°, 10°, 15°; L4-L5: 0°, 5°, 10°, 15°, 20°). There were three types of distances from the anterior vertebral cortex (AVC) to the PGVs (DAVC-PGV); DAVC-PGV < 0.50 cm, DAVC-PGV ≥ 0.50 cm, and DAVC-PGV↑; these distances represented close, distant, and noncontact PGV, respectively. RESULTS: The ratio of every type of PGV was calculated, and the appropriate TSA of the BPS was recommended. In L1, the recommended left TSA of the BPS was 0°, and the ratio of the close PGV was 7.69%, while the recommended right TSA was 0°-10°, and the ratio of the close PGV was 1.54-4.62%. In L2, the recommended left TSA of the BPS was 0° and the ratio of the close PGV was 1.54%, while the recommended right TSA was 0°-15° and the ratio of the close PGV was 3.08-9.23%. In L3, the recommended left TSA was 0°-5°, and the ratio of the close PGV was 1.54-4.62%. In L4, the recommended left TSA was 0°, and the ratio of the close PGV was 4.62%. BPS use was not recommended on the right side of either L3 or L4 or on the either side of L5. CONCLUSIONS: From the anatomical perspective of the PGVs, BPSs were not suitable for insertion into every lumbar vertebra. Furthermore, the recommended methods for inserting BPSs were different in L1-L4.

Survival trends after inferior vena cava and aortic injuries in the United States.

OBJECTIVE: Recent studies have demonstrated an increase in trauma mortality relative to mortality from cancer and heart diseases in the United States. Major vascular injuries such as to the inferior vena cava (IVC) and aortic injuries remain responsible for a significant proportion of early trauma deaths in modern trauma care. The purpose of this study was to explore patterns in epidemiology and mortality after IVC and aortic injuries in the United States. METHODS: A 13-year analysis of the National Trauma Databank (2002-2014) was performed to extract all patients who sustained IVC, abdominal aortic, or thoracic aortic injuries. Demographics, clinical data, and outcomes were extracted. Patients were analyzed according to injury mechanism. RESULTS: A total of 25,428 patients were included in this analysis. Overall, the mean age was 39.8 ± 19.1 years, 70.3% were male, and 14.1% sustained a penetrating trauma. Although the incidence of all three injuries remained constant throughout the study period, for blunt trauma, mortality decreased over the study period (from 48.8% in 2002 to 28.7% in 2014; P < .001), in particular for thoracic aortic injuries (from 46.1% in 2002 to 23.7% in 2014; P < .001) and abdominal aortic injuries (from 58.3% in 2002 to 26.2% in 2014; P < .001). This decrease in mortality after blunt trauma was accompanied by an increase in endovascular procedures over the study period (from 1.0% in 2002 to 30.4% in 2014; P < .001), in particular for blunt thoracic aortic injuries (from 0.7% in 2002 to 41.4% in 2014; P < .001). When penetrating trauma patients were analyzed, overall there was an increase in mortality (from 43.8% in 2002 to 50.6% in 2014; P < .001), in particular after abdominal aortic injury (from 30.4% in 2002 to 66.0% in 2014; P < .001). Similar trends were observed for IVC injuries. No increase in endovascular use in penetrating trauma was identified (from 0.1% in 2002 to 3.4% in 2014; P < .001). CONCLUSIONS: The present study demonstrates an overall decrease in mortality after blunt aortic injuries in the United States. This decrease was accompanied by an increase in the use of endovascular procedures. After penetrating trauma, however, despite contemporary advances in trauma care, mortality has increased over the study period, in particular after abdominal aortic injury. No increase in endovascular use in penetrating trauma was demonstrated.

Comparison of zone 3 Resuscitative Endovascular Balloon Occlusion of the Aorta and the Abdominal Aortic and Junctional Tourniquet in a model of junctional hemorrhage in swine.

BACKGROUND: Traumatic injuries to the pelvis and high junctional injuries are difficult to treat in the field; however, Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) and the Abdominal Aortic and Junctional Tourniquet (AAJT) constitute two promising treatment modalities. The aim of this study is to use a large animal model of pelvic hemorrhage to compare the survival, hemostatic, hemodynamic, and metabolic profile of both techniques. METHODS: Yorkshire swine (n = 10, 70-90 kg) underwent general anesthesia, instrumentation, and surgical isolation of the femoral artery. Uncontrolled hemorrhage was initiated by an arteriotomy. Animals were randomly allocated to either REBOA or AAJT. Following completion of device application, both groups received a 500 mL Hextend bolus. After 1 hour, the injured femoral artery was ligated to simulate definitive hemostasis followed by a second Hextend bolus and device removal. Animals were observed for two more hours. Physiological data were collected throughout the experiments and compared between groups. RESULTS: Both techniques achieved 100% hemostasis, and all animals survived the entire experiment except one in the REBOA group. During the hour treatment phase, the AAJT group had a higher mean arterial pressure than the REBOA group (59.9 ± 16.1 versus 44.6 ± 9.8 mm Hg, respectively; P < 0.05). The AAJT-treated group had higher lactate levels than the REBOA-treated group (4.5 ± 2.0 versus 3.2 ± 1.3 mg/dL, respectively; P < 0.05). CONCLUSIONS: Despite their mechanistic differences, both techniques achieved a similar hemostatic, hemodynamic, and metabolic profile. Some differences do exist including lactate levels and blood pressure.

Management and Evolution of a Wallstent Migration in a Pediatric Blunt Traumatic Abdominal Aortic Injury.

Blunt traumatic abdominal aortic injury in children is a rare but a severe condition. The clinical manifestation often involves other intra-abdominal visceral injuries and vertebral fractures. The best therapeutic management is still unclear with few reported endovascular cases treated. The following is the case of a 13-year-old male with an aortic abdominal dissection, spleen laceration, jejunal contusion, and hemoperitoneum after a motor vehicle collision. An endovascular approach was decided upon after the progression of the intimal aortic tear. A self-expanding stent was implanted into the injured position with an immediate proximal migration to the visceral aorta. It was decided not to retrieve the stent because of added comorbidity, and an open repair of the dissection was performed using a graft bypass. The patient has completed a 6-year image surveillance without complications or growth alterations. To our knowledge, this is the first reported childhood case of an intraoperative stent migration during the endovascular treatment of a blunt traumatic abdominal aortic injury. The possible cause of the complication and the management of these kinds of injuries are reviewed in detail in this article.

Seat-Belt Abdominal Aortic Injury-Treatment Modalities.

Blunt abdominal aortic injuries are extremely rare, diagnosed in less than 0.05% of all trauma admissions. Aortic injury caused by a seat belt during a car accident is often referred as "seat-belt aorta". We present a case of an 18-year-old woman, restrained back passenger involved in a vehicular collision, sustaining vertebral column and multiple rib fractures, mesenterium and colonic injury, and infrarenal aortic contusion with localized dissection and partial thrombosis.

Adenosine triphosphate as a molecular mediator of the vascular response to injury.

BACKGROUND: Human saphenous veins used for arterial bypass undergo stretch injury at the time of harvest and preimplant preparation. Vascular injury promotes intimal hyperplasia, the leading cause of graft failure, but the molecular events leading to this response are largely unknown. This study investigated adenosine triphosphate (ATP) as a potential molecular mediator in the vascular response to stretch injury, and the downstream effects of the purinergic receptor, P2X7R, and p38 MAPK activation. MATERIALS AND METHODS: A subfailure stretch rat aorta model was used to determine the effect of stretch injury on release of ATP and vasomotor responses. Stretch-injured tissues were treated with apyrase, the P2X7R antagonist, A438079, or the p38 MAPK inhibitor, SB203580, and subsequent contractile forces were measured using a muscle bath. An exogenous ATP (eATP) injury model was developed and the experiment repeated. Change in p38 MAPK phosphorylation after stretch and eATP tissue injury was determined using Western blotting. Noninjured tissue was incubated in the p38 MAPK activator, anisomycin, and subsequent contractile function and p38 MAPK phosphorylation were analyzed. RESULTS: Stretch injury was associated with release of ATP. Contractile function was decreased in tissue subjected to subfailure stretch, eATP, and anisomycin. Contractile function was restored by apyrase, P2X7R antagonism, and p38-MAPK inhibition. Stretch, eATP, and anisomycin-injured tissue demonstrated increased phosphorylation of p38 MAPK. CONCLUSIONS: Taken together, these data suggest that the vascular response to stretch injury is associated with release of ATP and activation of the P2X7R/P38 MAPK pathway, resulting in contractile dysfunction. Modulation of this pathway in vein grafts after harvest and before implantation may reduce the vascular response to injury.

Open and Endovascular Abdominal Aortic Injury Repair Outcomes in Polytrauma Patients.

INTRODUCTION: The management of patients with abdominal aortic injury (AAI) remains challenging. Open repair of AAI is still the standard of care although it is associated with high mortality. In past few years, endovascular surgery has evolved as a less invasive alternative to open surgery in emergency settings. The objective of this study was to compare outcomes after open repair versus endovascular repair of AAI in polytrauma patients. METHODS: The National Trauma Data Bank, from 2008 to 2012, was queried to identify trauma patients undergoing open and endovascular repair of AAI using International Classification of Diseases, ninth Edition, and Clinical Modification codes. Data reviewed included demographics, type of associated injury, type of operative management, and complications. Factors independently associated with mortality were evaluated using multivariate logistic regression model. RESULTS: Of 325 injured patients with AAI, 91 patients underwent endovascular repair and 234 patients underwent open repair. Of these, 80.6% were male, with a mean age of 35.70 years, and a mean injury severity score (ISS) was 30.59 for patients undergoing open repair and 31.56 for endovascular repair. Associated traumatic injuries included bowel injuries 57.5%, liver-pancreas injuries 36.6%, splenic injuries 14.8%, renal injuries 15.7%, and retroperitoneal injuries 19.1%. In-patient mortality for patients undergoing the open repair cohort was 63.7% and 20.9% for patients in the endovascular cohort (P < 0.001). The endovascular repair cohort patients had a higher incidence of pneumonia 17.6% as compared to open repair cohort 5.1% (P < 0.001). Similarly, patients in the endovascular repair cohort also had a higher abdominal compartment syndrome (4.4% vs. 0.4% in the open repair cohort, P = 0.009), postoperative acute kidney injury (9.9% endovascular repair cohort vs. 6.4% in the open repair cohort, P = 0.281), and acute mesenteric ischemia (1.1%). After controlling for associated injuries, acidosis, blood pressure at presentation, age, and ISS, patients in the open repair cohort had 6.58 times higher odds (confidence interval: 3.25-13.33; P < 0.001) of mortality as compared to the endovascular repair cohort. CONCLUSIONS: Endovascular repair of abdominal aorta in polytrauma patients seems to be feasible and may improve survivorship in appropriately selected patients. More research is needed to understand to identify indications for endovascular repair versus open repair.

Cholesteryl ester transfer protein inhibition enhances endothelial repair and improves endothelial function in the rabbit.

OBJECTIVE: High-density lipoproteins (HDLs) can potentially protect against atherosclerosis by multiple mechanisms, including enhancement of endothelial repair and improvement of endothelial function. This study asks if increasing HDL levels by inhibiting cholesteryl ester transfer protein activity with the anacetrapib analog, des-fluoro-anacetrapib, enhances endothelial repair and improves endothelial function in New Zealand White rabbits with balloon injury of the abdominal aorta. APPROACH AND RESULTS: New Zealand White rabbits received chow or chow supplemented with 0.07% or 0.14% (wt/wt) des-fluoro-anacetrapib for 8 weeks. Endothelial denudation of the abdominal aorta was carried out after 2 weeks. The animals were euthanized 6 weeks postinjury. Treatment with 0.07% and 0.14% des-fluoro-anacetrapib reduced cholesteryl ester transfer protein activity by 81±4.9% and 92±12%, increased plasma apolipoprotein A-I levels by 1.4±0.1-fold and 1.5±0.1-fold, increased plasma HDL-cholesterol levels by 1.8±0.2-fold and 1.9±0.1-fold, reduced intimal hyperplasia by 37±11% and 51±10%, and inhibited vascular cell proliferation by 25±6.1% and 35±6.7%, respectively. Re-endothelialization of the injured aorta increased from 43±6.7% (control) to 69±6.6% and 76±7.7% in the 0.07% and 0.14% des-fluoro-anacetrapib-treated animals, respectively. Aortic ring relaxation and guanosine 3',5'-cyclic monophosphate production in response to acetylcholine were also improved. Incubation of HDLs from the des-fluoro-anacetrapib-treated animals with human coronary artery endothelial cells increased cell proliferation and migration relative to control. These effects were abolished by knockdown of scavenger receptor-B1 and PDZ domain-containing protein 1 and by pharmacological inhibition of phosphatidylinositol-4,5-bisphosphate 3-kinase/Akt. CONCLUSIONS: Increasing HDL levels by inhibiting cholesteryl ester transfer protein reduces intimal thickening and regenerates functional endothelium in damaged New Zealand White rabbit aortas in an scavenger receptor-B1-dependent and phosphatidylinositol-4,5-bisphosphate 3-kinase/Akt-dependent manner.

Observation May Be Safe in Selected Cases of Blunt Traumatic Abdominal Aortic Injury.

BACKGROUND: Blunt traumatic abdominal aortic injury (BTAAI) is a rare lesion, often associated with extensive intraperitoneal injuries. Optimal management remains unclear, including the role of prosthetic aortic graft replacement with concomitant bowel injury and the management of small pseudoaneurysms. METHODS: We reviewed BTAAI cases occurring between 2000 and 2014. Thoracic and isolated iliac artery injuries were excluded. We included patient demographics, mechanism of injury, admission physiology, and reviewed available imaging to characterize aortic injury type and severity. RESULTS: BTAAI was noted in 16 of 8,751 (0.2%) blunt abdominal trauma patients admitted during the study period. Of these, 56% were males and the median age was 47 years (range, 5-80). Aortic repair was attempted in 7 patients, including 3 open prosthetic aortobi-iliac bypass grafts, 1 endovascular repair, and 2 primary repairs. One patient died before repair. The remaining patients were medically managed for their aortic injury, including 3 with pseudoaneurysm and 3 with large intimal flaps. There were 5 in-hospital deaths (31%) but only 1 attributed to aortic injury. Among patients surviving to discharge, there were no readmissions or delayed deaths. All nonoperative and surgically repaired patients seen in follow-up had stable aortic lesions. No patient with graft or endograft repair had evidence of graft infection on follow-up (median, 52 months; range, 21-121). CONCLUSIONS: BTAAI is a rare entity and is associated with high in-hospital mortality, primarily due to associated injuries. Observation of selected small pseudoaneurysms and intimal flaps appear safe. Survival after hospital discharge is excellent, and aortic-related complications are rare. The indications for repair and the role of revascularization with in situ prosthetic graft in the setting of concomitant bowel injuries are not well defined.