Lower Extremity Vascular Injury in the Pediatric Trauma Patient: Management and Outcomes at an Adult Level I Trauma Center.

BACKGROUND: Traumatic vascular injuries of the lower extremity in the pediatric population are uncommon but can result in significant morbidity. The objective of this study is to demonstrate our experience with these injuries by describing patterns of traumatic vascular injury, the initial management, and data regarding early outcomes. METHODS: In total, 506 patients presented with lower extremity vascular injury between January 1, 2009 and January 1, 2021 to Grady Memorial Hospital, an urban, adult Level I trauma center in Atlanta, Georgia. Thirty-two of the 506 patients were aged less than 18 years and were evaluated for a total of 47 lower extremity vascular injuries. To fully elucidate the injury patterns and clinical course in this population, we examined patient demographics, mechanism of injury, type of vessel injured, surgical repair performed, and early outcomes and complications. RESULTS: The median (interquartile range) age was 16 (2) years (range, 3-17 years), and the majority were male (n = 29, 90.6%). Of the vascular injuries identified, 28 were arterial and 19 were venous. Of these injuries, 14 patients had combined arterial-venous injuries. The majority of injuries were the result of a penetrating injury (n = 28, 87.5%), and of these, all but 2 were attributed to gunshot wounds. Twenty-seven vascular interventions were performed by nonpediatric surgeons: 11 by trauma surgeons, 13 by vascular surgeons, 2 by orthopedic surgeons, and 1 by an interventional radiologist. Two patients required amputation: 1 during the index admission and 1 delayed at 3 months. Overall survival was 96.9%. CONCLUSIONS: Vascular injuries as the result of trauma at any age often require early intervention, and we believe that these injuries in the pediatric population can be safely managed in adult trauma centers with a multidisciplinary team composed of trauma, vascular, and orthopedic surgeons with the potential to decrease associated morbidity and mortality from these injuries.

Aggressive Treatment Strategy at Index TEVAR Is Associated With Reduced Need For Short-Term Reintervention In Patients With Aortic Dissection.

INTRODUCTION: Thoracic endovascular aortic surgery (TEVAR) is the modern standard of treatment for patients with Type B aortic dissection, however it is unclear how the initial length of treated aorta affects long-term outcomes. This study aims to elucidate risk factors for secondary intervention after TEVAR for aortic dissection, focusing on length of aortic treatment at index operation. METHODS: A retrospective multihospital chart review was completed for patients treated between 2011 and 2022 who underwent TEVAR for aortic dissection with at least one year of post-TEVAR imaging and follow-up. Patient demographics and characteristics were analyzed. In this study, aortic zones treated only included those managed with a covered stent graft. The primary outcome measure was any need for secondary intervention. RESULTS: A total of 151 patients were identified. Demographics included a mean age of 57 years, with 31.8% of the patients being female. Forty-three patients (28.5%) underwent secondary intervention after TEVAR, with a mean follow-up of 1.6 years. The most common indication for secondary intervention was aneurysmal degeneration of the residual false lumen (76%). There was a significant difference in the number of aortic zones treated in patients who did and did not require secondary intervention (2.3 ± 1 vs. 2.7 ± 1, p = 0.04). Additionally, patients with three or more aortic zones of treatment had a significant difference in the need for reintervention (32% secondary intervention vs 52% no secondary intervention, p = 0.02). CONCLUSIONS: At least three zones of aortic treatment at index TEVAR is associated with a decreased need for overall reintervention. Modern treatment of acute and subacute type B dissection should stress an aggressive initial repair, balanced by the potential increased risk of spinal cord ischemia.

Vascular surgery is the most commonly consulted specialty for emergent operative trauma.

OBJECTIVE: Despite an increasing rate of intraoperative consultation of vascular surgery (VS) for trauma patients, VS is not one of the subspecialties required for American College of Surgeons level I trauma center verification. We sought to assess the rates and patterns of emergent operative VS consultation compared with other surgical subspecialties in the trauma setting. METHODS: A retrospective analysis was performed on all patients who presented with traumatic injuries requiring emergent surgical operations (<3 hours after presentation) from 2015 to 2019 at a level I trauma center. Patient demographics, injury characteristics, and data on consulted surgical subspecialties were collected. The primary outcome measured was the rate of intraoperative consultation to VS and other subspecialties (OS). RESULTS: A total of 2265 patients were identified, with 221 emergent intraoperative consults to VS and 507 consults to OS. After VS (9.8%), the most common subspecialties consulted were orthopedics (9.2%) and urology (5%). Overall, VS was more likely to be consulted in immediate trauma operations (<1 hour after presentation) (65.6% vs 38.1%, P < .0001), penetrating injuries (73.3% vs 47.9%, P < .0001), and at night (60.6% vs 51.9%, P = .02) compared with OS. Time from admission to operation was shorter for cases when VS was involved compared with OS (54.1 ± 40.4 vs 80.6 ± 47.9 minutes, P < .0001). In a multivariable logistic regression model, we found that requiring an immediate operation was associated with higher odds of requiring an intraoperative vascular consult (odds ratio = 1.49, 95% confidence interval = 1.12-2.0). CONCLUSIONS: Vascular surgeons are consulted intraoperatively to assist with emergent trauma at a greater rate compared with specialties that are required for level I trauma center verification. Current American College of Surgeons verification processes and site-specific policies should be re-evaluated to consider VS coverage as a requirement for trauma center verification.

Female gender is associated with increased late luminal narrowing within the stent graft after thoracic endovascular aortic repair.

BACKGROUND: Luminal narrowing, suspected secondary to thrombus, occurs within stent grafts at an unclear incidence after thoracic endovascular aortic repair (TEVAR). The significance of this phenomenon has not been determined, nor have the risk factors for development of intragraft luminal narrowing. Small graft diameter is hypothesized to be a risk factor for the development of ingraft stenosis. METHODS: A retrospective analysis was performed of a multicenter healthcare system including all patients who underwent TEVAR between July 2011 and July 2019 with at least 1 year of subsequently available surveillance contrast-enhanced computed tomography imaging. Standard demographic, preoperative, intraoperative, and postoperative variables were collected. Measurements were obtained via direct off-line images from computed tomography scans. Patent intragraft diameters were compared with baseline and interval change values were normalized to time to follow-up. The primary outcome measure was annual rate of intragraft luminal narrowing. RESULTS: There were 208 patients who met the inclusion criteria (94 women, 114 men) with a median follow-up of 822 days. The mean annual rate of percent intragraft diameter reduction was 10.5 ± 7.7% for women and 7.6 ± 5.6% for men (P = .0026). Multivariate analysis demonstrated female gender (P = .0283), preoperative diagnosis of hypertension (P = .0449), and need for coverage of the left subclavian artery (P = .0328) were all significant predictors of intragraft luminal narrowing. Small aortic diameters were not found to be associated independently with ingraft luminal narrowing nor was the concomitant use of antiplatelet or anticoagulation medications. Significant amounts of ingraft luminal narrowing, defined as a greater than 20% intragraft diameter decrease, were associated with an increased need for any reintervention, including for malperfusion, endoleak, and symptomatic aneurysm (P = .0249). Kaplan-Meier estimates demonstrated a significant gender-associated difference in high rates of intragraft luminal narrowing (P = .00189). CONCLUSIONS: In this analysis, female gender is shown to be a significant nonmodifiable risk factor for intragraft luminal narrowing after TEVAR. The development of this phenomenon is not benign; as such, these findings were associated with an increased need for reintervention. This finding may be attributable to differences in aortic compliance or gender-associated differences in coagulation pathways and merits further investigation. Surveillance after thoracic stent grafting must account for patient-specific variations in complication risk.

Apolipoprotein A-I, elevated in trauma patients, inhibits platelet activation and decreases clot strength.

Apolipoprotein A-I (ApoA-I) is elevated in the plasma of a subgroup of trauma patients with systemic hyperfibrinolysis. We hypothesize that apoA-I inhibits platelet activation and clot formation. The effects of apoA-I on human platelet activation and clot formation were assessed by whole blood thrombelastography (TEG), platelet aggregometry, P-selectin surface expression, microfluidic adhesion, and Akt phosphorylation. Mouse models of carotid artery thrombosis and pulmonary embolism were used to assess the effects of apoA-I in vivo. The ApoA-1 receptor was investigated with transgenic mice knockouts (KO) for the scavenger receptor class B member 1 (SR-BI). Compared to controls, exogenous human apoA-I inhibited arachidonic acid and collagen-mediated human and mouse platelet aggregation, decreased P-selectin surface expression and Akt activation, resulting in diminished clot strength and increased clot lysis by TEG. ApoA-I also decreased platelet aggregate size formed on a collagen surface under flow. In vivo, apoA-I delayed vessel occlusion in an arterial thrombosis model and conferred a survival advantage in a pulmonary embolism model. SR-BI KO mice significantly reduced apoA-I inhibition of platelet aggregation versus wild-type platelets. Exogenous human apoA-I inhibits platelet activation, decreases clot strength and stability, and protects mice from arterial and venous thrombosis via the SR-BI receptor.

Pre-existing Systolic Dysfunction is the Most Powerful Predictor of Failed Arteriovenous Fistula Maturation.

BACKGROUND: Patients requiring hemodialysis access creation often have significant comorbid conditions, which may impact access maturation. Underlying cardiac dysfunction likely plays an important role in the maturation of arteriovenous fistulae (AVF). The effect of specific parameters of cardiac function on successful AVF creation has not previously been explored. METHODS: A retrospective chart analysis of patients undergoing first-time AVF creation at a single center from 2011 to 2018 was performed. Patients with a transthoracic echocardiogram within the 12 months prior to surgery were included. Standard demographic and perioperative variables were collected, in addition to echocardiographic and vascular mapping data. The primary outcome was access maturation, defined as the use of the access site for hemodialysis at 3, 6, and 12 months after surgery. RESULTS: A total of 121 patients met inclusion criteria with a cumulative AVF maturation rate of 57% (69/121) in this select population. Patients with pre-existing systolic cardiac dysfunction were more than 5 times less likely to see their AVF mature by one year postsurgery (OR = 0.17, P = 0.018). Preoperative venous diameter, access site location, and the type of fistula did not differ significantly between patients with and without systolic dysfunction. Selection of the cephalic vein as the venous anastomosis and diastolic dysfunction (≥ Grade 2) were also associated with lower rates of access maturation, although these associations were less robust. CONCLUSIONS: Systolic cardiac dysfunction is the most important nonmodifiable variable associated with failed AVF maturation. Patients requiring hemodialysis with significant pre-existing cardiac dysfunction may not be appropriate for permanent access creation, and long-term catheter use should be seriously considered as an alternative.

Influence of baseline kidney dysfunction on perioperative renal outcomes after endovascular aneurysm repair with suprarenal fixation.

BACKGROUND: Conflicting evidence exists regarding the comparative effects of endovascular aneurysm repair (EVAR) with and without suprarenal fixation. We compare outcomes in patients treated by EVAR with baseline normal kidney function and moderate and severe chronic kidney disease. METHODS: Patients with normal kidney function (glomerular filtration rate [GFR] ≥60 mL/min/1.73 m2) or moderate (GFR = 30-59 mL/min/1.73 m2) or severe (GFR <30 mL/min/1.73 m2) kidney disease who underwent EVAR (N = 5534) were identified from the American College of Surgeons National Surgical Quality Improvement Program targeted database (2011-2015). Groups were determined by the presence (Cook Zenith [Cook Medical, Bloomington, Ind] or Medtronic Endurant [Medtronic, Minneapolis, Minn]) or absence (Gore Excluder [W. L. Gore & Associates, Flagstaff, Ariz]) of a suprarenal fixation system. Postoperative renal complications, defined as rise in creatinine concentration of >2 mg/dL without dialysis or new dialysis requirements, were analyzed within the first 30 days with results stratified by degree of kidney disease. RESULTS: A total of 5534 patients underwent EVAR, with 3225 (58.3%) receiving a device using a suprarenal fixation system. Suprarenal fixation systems were less commonly used for symptomatic patients (11.0% vs 13.7%; P = .002) and patients with ruptured abdominal aortic aneurysm (4.5% vs 6.3%; P = .01). There was no difference in baseline kidney function between groups. EVAR with suprarenal fixation was associated with more renal complications (1.40% vs 0.65%; P = .008). In subgroup analysis, patients with moderate kidney dysfunction (n = 1780) had more renal complications (2.2% vs 0.8%; P = .02) with suprarenal fixation systems. No differences were seen in patients with normal kidney function (0.4% vs 0.2%; P = .32; n = 3597) or severe kidney dysfunction (14.3% vs 10.2%; P = .45; n = 157). This difference was driven mostly by postoperative elevation of creatinine concentration (0.6% vs 0.2%; P = .03) without requirements for new dialysis (0.8% vs 0.4%; P = .08). After adjustments with multivariate logistic regression models, EVAR with suprarenal fixation was associated with more renal complications (odds ratio, 2.65; 95% confidence interval, 1.32-5.34). CONCLUSIONS: In our study, EVAR with suprarenal fixation devices was associated with more perioperative renal complications in patients with moderate kidney dysfunction. Long-term evaluation of these patients undergoing EVAR should be considered.

Early Results of Popliteal Vein External Banding for Treatment of Chronic Venous Insufficiency.

BACKGROUND: Chronic venous insufficiency (CVI) encompasses a myriad of clinical manifestations including lower extremity swelling and pain, ulcerations and chronic skin changes such as stasis dermatitis, and lipodermatosclerosis. CVI effects greater than 25 million Americans and has a significant socioeconomic and psychosocial impact. Treatment of CVI varies depending on the etiology. For those patients with deep venous reflux, restoration of the deep venous valvular system is critical. Popliteal vein external banding is a novel technique to treat deep venous reflux. Our study aims to retrospectively review the early outcomes for the largest U.S. series of patients undergoing popliteal vein external banding. METHODS: Patients with C4, C5, and C6 disease with underlying deep venous reflux were treated with external banding of the popliteal vein. Basic demographic, ultrasound, and procedural data were collected. Patients were seen in clinic and underwent post procedure duplex. Procedure-specific complications were also assessed. The primary outcome was improvement of symptoms or wound healing. RESULTS: Twelve patients were identified. Seventy-five percent of patients had a history of DVT on the ipsilateral extremity and 66.7% (n = 6) of those patients had previous common or external iliac vein stenting for post-phlebitic syndrome. 58.3% of patients had active ulcerations (C6) at the time of popliteal vein banding and the mean VCSS score was 12.7, consistent with advanced venous disease. Patients were followed for a mean 8.62 months. Of the 8 patients that had active ulcers (C6), 75% completely healed with a mean time to healing of 3.3 months. 91.6% of patients reported clinical improvement in their symptoms (i.e., reduction in edema/swelling, pain or improvement in size of ulcer). Three patients had post-operative wound complications and 1 required oral antibiotic for associated cellulitis. CONCLUSION: Popliteal vein external banding represents a viable treatment modality for patients with venous insufficiency secondary to deep venous reflux. It is technically easier than most deep venous reconstructive options and may have an important role in the multimodal treatment of patients with advanced CVI.

Management and Outcomes after Upper Versus Lower Extremity Vascular Trauma.

BACKGROUND: While significant literature exists regarding peripheral vascular injury management, the vast majority focuses on lower extremity arterial injury. As a result, clinical management of arterial injury in the upper extremities is often guided by literature specific to lower extremity vessel injury. The purpose of this study is to use the largest series of patients reported in the literature to compare management and outcomes of upper and lower extremity traumatic vascular injuries. METHODS: Patients who underwent operative repair of traumatic vascular injuries of the extremities were identified from the trauma registry of a level I trauma center. A retrospective chart review (2011-2019) was conducted. Demographics, mechanism of injuries, operative techniques, and outcomes were compared between patients with upper versus lower extremity vascular injuries. RESULTS: Five hundred thirty-five patients were included with 234 (43.8%) patients undergoing repair of upper extremity vascular injuries. Patients with upper extremity vascular injuries were more likely to be female (16.7% vs. 9%, P = 0.007), have a pre-hospital tourniquet (21.8% vs. 12%,P = 0.002), have associated nerve injuries (40.2% vs. 4.7%, P < 0.0001) or present with bleeding (76.1% vs. 64.1%, P = 0.002) but were less commonly associated with concomitant fractures (25.6% vs. 39.9%, P = 0.0006). There was no difference in age, race, or mechanism of injury. In regards to operative management, upper extremity injuries were more likely to be managed with vessel ligation (38% vs. 17.6%, P < 0.0001) or primary reanastomosis (12.4% vs. 5.6%, P = 0.009) and were less frequently associated with concomitant fasciotomies (13.3% vs. 56.5%, P < 0.0001). Postoperatively, upper extremity injuries were associated with persistent nerve deficits (21.7% vs. 10%, P = 0.0002) while lower extremity injuries had a higher incidence of 30-day limb loss (5.7% vs. 1.3%, P = 0.008). There were no differences in mortality or graft-patency rates between groups. CONCLUSIONS: Upper extremity injuries are associated with a lower limb-loss rate but increased prevalence of neurological deficits after vascular trauma compared to lower extremities. A high level of suspicion is paramount to intraoperative identify associated nerve injuries to improve postoperative functional outcomes.

Vascular Surgeons Carry an Increasing Responsibility in the Management of Lower Extremity Vascular Trauma.

BACKGROUND: There is preliminary evidence that vascular surgeons are increasingly relied on nationally to assist with the management of lower extremity vascular trauma. Current trauma center verification, however, does not require any level of vascular surgery coverage. We sought to assess practice patterns regarding vascular surgery consultation and temporal trends in the surgical management of these patients. METHODS: A retrospective analysis was performed on all patients who underwent surgical repair for vascular trauma of the lower extremity at a single, academic, public hospital from 2011 to 2018. Demographic data and procedural data were collected. Patients were assigned to a vascular surgery (VS) or nonvascular surgery (NV) group. The primary outcome measure was the rate of VS consultation. Secondary outcome measures included 30-day mortality, length-of-stay, and limb salvage. RESULTS: One hundred eighty patients were identified (77 VS group, 103 NV group). There was an increase in the proportion of repairs done by VS from 2011 to 2018 (P < 0.05). There were significant management differences between the 2 groups, with vascular surgeons more likely to perform primary end-to-end anastomosis for both arterial (21.33% vs. 6.90%) and venous (19.15% vs. 5.26%) injuries (both P < 0.05). Patients in the VS group were less likely to have balloon embolectomy, fasciotomy, or intravascular shunting than the NV group (all P < 0.05). There were no significant differences in mortality (5.35% vs. 4.85%), length-of-stay (15.05 vs. 18.38 days), or limb salvage (94.81% vs. 95.15%). CONCLUSIONS: Lower extremity vascular trauma is increasingly managed by vascular surgeons. Furthermore, vascular surgeons are more selective in the use of potentially unnecessary adjunctive maneuvers. Current accreditation guidelines should be revisited to mandate vascular surgery coverage in trauma centers that frequently treat this patient population.

Pharmacologic Therapy is Not Associated with Stroke Prevention in Patients with Isolated Blunt Vertebral Artery Injury.

BACKGROUND: Vertebral artery injury (VAI) is often grouped with carotid artery injury into a broader classification of blunt cerebrovascular injury, despite fundamental differences in mechanism of injury and outcome. This study seeks to evaluate the efficacy of medical therapy in preventing strokes for isolated VAI. METHODS: Patients with isolated blunt VAI (2011-2018) were identified from the trauma registry of a level I trauma center. A retrospective chart review was conducted excluding patients with concomitant carotid artery injury. Factors examined included demographics, injury characteristics, anatomic classification, and management strategy. Patients were stratified by whether they received pharmacological (antiplatelet or anticoagulation) therapy. The primary outcome was new posterior circulation stroke within 30 days of injury as confirmed by imaging studies. RESULTS: A total of 206 patients with blunt VAI were included. Median Injury Severity Score was 17 and 33 (16.0%) patients presented with Glasgow Coma Scale <8. The most common mechanism of injury was motor vehicle collision (58.7%). The injuries were bilateral in 38 (18.5%) patients and 73 (35.4%) suffered multisegmental injuries. The anatomic severity of injuries was Grade 1 = 38.8%, Grade 2 = 25.7%, Grade 3 = 4.9%, Grade 4 = 30.6%, and Grade 5 = 0.5%. There was no correlation between anatomic grade and stroke (P = 0.11) or initiation of pharmacologic therapy (P = 0.30). In total, 172 (84%) patients received pharmacological therapy with no differences in baseline characteristics between treated and untreated patients. Overall, the 30-day stroke rate was 1.9%. There was no difference in stroke rate between patients who received medical therapy versus those who did not (5.9% vs. 1.2%, P = 0.13). In subgroup analysis by injury severity, medical therapy did not improve stroke rates. Among patients treated with aspirin, there was no difference in stroke rate between doses of 81 vs. 325 mg (1.1% vs. 0%, P = 1). CONCLUSIONS: Isolated VAI is associated with a very low risk of stroke and treatment with medical therapies including antiplatelet or anticoagulation does not improve risk of stroke.

Stent Graft Oversizing is Associated with an Increased Risk of Long-Term Left Ventricular Wall Thickening in Young Patients Following Thoracic Endovascular Aortic Repair.

BACKGROUND: Left ventricular (LV) wall thickening occurs in patients following thoracic endovascular aortic repair (TEVAR). Clinical consequences of cardiovascular (CV) remodeling may be more significant younger patients with longer anticipated life spans. Risk factors for CV remodeling following TEVAR are unknown but may be related to graft size. METHODS: A retrospective analysis was performed of a multicenter healthcare system including patients aged ≤60 who underwent TEVAR between 2011 and 2019 with at least 1 year follow-up computed tomography angiography imaging available. Standard perioperative variables, native aortic diameter, and stent graft specifications were collected. Graft oversizing was calculated by dividing proximal graft diameter by proximal aortic diameter on preoperative imaging. Posterior LV wall thickness was measured at baseline and interval increases were normalized to time-to-follow-up. Primary outcome was annual rate of posterior LV wall thickening. RESULTS: One hundred one patients met inclusion criteria with a mean (SD) follow-up time of 1270 (693) days. Overall mean (SD) rate of LV wall thickness change was 0.534 (0.750) mm per year. Mean (SD) absolute LV wall thickness at most recent follow-up was 10.97 (2.85) mm for men, 9.69 (2.03) mm for women. Multivariate analysis demonstrated that higher rates of LV wall thickening were associated with narrower graft diameters (P = 0.0311). Greater absolute LV wall thickness at follow-up was associated with narrower grafts (P= 0.0155) and greater graft oversizing (P= 0.0376). Logistic regression demonstrated individuals who met criteria for LV hypertrophy were more likely to have narrower stent-grafts (P= 0.00798) and greater graft oversizing (P= 0.0315). CONCLUSIONS: LV wall thickening occurred to a greater degree in individuals with narrower stent-grafts and higher rates of graft oversizing. This has significant implications for long-term cardiovascular health in younger patients may undergo TEVAR for atypical indications. Particular attention should be paid to long-term effects of stent-graft oversizing when selecting grafts in such populations.

Sudden death due to leukostasis in a subject with undiagnosed chronic lymphocytic leukemia.

Sudden death due to leukostasis and lymphocyte thrombi in patients with chronic hematologic malignancies is rare. Leukostasis is characterized by highly elevated leukemic cell count and decreased tissue perfusion symptoms, leading to severe complications and even death. Chronic lymphocytic leukemia (CLL) is a chronic lymphoproliferative disorder that shows a highly heterogeneous clinical course, ranging from indolent form to very aggressive disease. Due to its low metabolic and mitotic rate, there is a lower incidence of clinically significant leukostasis in patients with CLL. Two main theories have been proposed in the development of leukostasis: (1) increased blood viscosity due to large leukemic cell populations; (2) high metabolic activity and cytokine production by leukemic cells. Both mechanisms lead to local hypoxic damage.We present a case of a 70-year-old man who died suddenly in the absence of symptoms. Autopsy and histology examinations revealed findings consistent with CLL and diffuse leukostasis involving the major organs' vessels.In the presence of gross and/or microscopic findings suggesting a potential hematologic malignancy, undiagnosed or relapsing hematologic malignancies should be considered in the differential diagnosis of sudden deaths.

Generation of Linear Impulse During the Takeoff of the Long Jump.

This study investigates the effect of initial leg angle on horizontal jump performance. Eleven highly skilled male and female long jumpers (national and Olympic level) performed a series of horizontal jumps for distance. Within-jumper differences in initial leg angle, normalized horizontal and net vertical impulses, contact time, and average reaction force during the impact interval, post-impact interval, and in total were measured using highspeed video (240 or 300 Hz) and a force plate (1200 Hz). Pearson correlations, Winsorized correlations, and the HC4 method were used to determine significant correlations between variables (α = 0.05). Within-jumper analysis indicated that when jumpers initiate the takeoff phase with a larger leg angle they are able to generate significantly greater negative horizontal and positive net vertical impulse (n = 7). Increased impulse generation was the result of increased contact time (n = 5 of 7) and / or increased average reaction force (n = 4) during the impact interval (n = 3) and / or post-impact interval (n = 4), depending on the individual. Initial leg configuration at contact and individual specific impulse generation strategies are important to consider when determining how an athlete with initial momentum can increase impulse generation to jump for distance.

Suprageniculate Approach to Release of Popliteal Entrapment without Distal Bypass Despite Preoperative Runoff Thrombosis.

BACKGROUND: Popliteal artery entrapment syndrome is an uncommon condition in which anatomic or functional popliteal artery compression causes arterial insufficiency. We present a case of popliteal entrapment with runoff thrombosis treated with suprageniculate release of entrapment without distal bypass. RESULTS: A 15-year old boy with Klinefelter syndrome presented with right leg claudication severely limiting his activity. He had a palpable femoral pulse, but no palpable popliteal or foot pulses on the right. Noninvasive testing showed a partially thrombosed popliteal artery with an ankle-brachial index (ABI) of 0.69. Computed tomography scan revealed type III popliteal entrapment with distal thromboses and abnormal insertion of gastrocnemius muscle. Popliteal entrapment release was performed via a medial suprageniculate approach in consideration for distal bypass. The soleus was released first; intraoperative angiography showed continued popliteal compression with forced dorsiflexion. This was followed by release of the gastrocnemius and found caudal and medial to the soleus as a tight band. Repeat angiography showed cessation of popliteal artery compression with dorsiflexion. Bypass was not performed due to improvement of distal flow seen on angiography. Postoperative recovery was unremarkable. On 1-month and 9-month follow-up, he had a normal ABI and arterial duplex, was asymptomatic, and had returned to normal activities. CONCLUSIONS: We describe suprageniculate approach to popliteal release that may be useful if a distal bypass is planned. In this case, bypass was unnecessary despite the abnormal appearance of distal runoff on preoperative imaging, as the child's perfusion improved with entrapment release alone, and arterial remodeling over time resulted in normal perfusion and arterial appearance on duplex imaging.

Thrombelastographic pattern recognition in renal disease and trauma.

BACKGROUND: Thrombelastography (TEG) is a viscoelastic hemostatic assay. We have observed that end-stage renal disease (ESRD) and trauma-induced coagulopathy (TIC) produce distinctive TEG tracings. We hypothesized that rigorously definable TEG patterns could discriminate between healthy controls and patients with ESRD and TIC. METHODS: TEG was performed on blood from ESRD patients (n = 54) and blood from trauma patients requiring a massive blood transfusion (n = 16). Plots of independent TEG parameters were analyzed for patterns coupled to disease state, compared with controls. Decision trees for taxonomic classification were then built using the "R-Project" statistical software. RESULTS: Minimally overlapping clusters of TEG results were observed for the three patient groups when coordinate pairs of maximum amplitude (MA) and TEG-activated clotting time (ACT) were plotted on orthogonal axes. Based on these groupings, a taxonomical classification tree was constructed using MA and TEG ACT. Branch points were set at an ACT of 103 s, and these branches subdivided for MA at 60.8 mm for the high ACT branch and 72.6 mm for the low ACT branch, providing a correct classification rate of 93.4%. CONCLUSIONS: ESRD and TIC demonstrate distinct TEG patterns. The coagulopathy of ESRD is typified by a prolonged enzymatic phase of clot formation, with normal-to-elevated final clot strength. Conversely, TIC is typified by prolonged clot formation and weakened clot strength. Our taxonomic categorization constitutes a rigorous system for the algorithmic interpretation of TEG based on cluster analysis. This will form the basis for clinical decision support software for viscoelastic hemostatic assays.

Vein diameter, obesity, and rates of recanalization after mechanochemical ablation.

INTRODUCTION: AND OBJECTIVES: Large vein diameter is associated with higher recanalization rates after endovenous thermal ablation procedures of the great and small saphenous veins. However, relatively few studies have explored the relationship between vein diameter and recanalization rates after mechanochemical ablation (MOCA). METHODS: We conducted a retrospective review of patients with chronic venous insufficiency who underwent MOCA of the great or small saphenous vein from 2017-2021 at a single hospital. Patients with no follow-up ultrasound were excluded. Patients were classified as having a large (≥ 1 cm) or small (< 1 cm) treated vein. The primary outcomes were 2-year recanalization and reintervention of the treated segment. RESULTS: A total of 186 MOCA procedures during the study period were analyzed. There was no difference in age, gender, history of venous thromboembolic events, use of anticoagulation, obesity, or length of treated segment between cohorts. Patients with large veins were less likely to have stasis ulcers compared to those with small veins (3.2% vs 21.5%; p<.05 on Fisher exact test). Patients with large veins had a higher incidence of local post-operative local complications (24.2% vs 7.2%, p<.05 on Chi-squared test). A survival analysis with Cox proportional hazards showed no significant difference in recanalization rates with larger vein diameters. However, obesity was found to significantly correlate with recanalization. CONCLUSIONS: Large vein diameter was not associated with higher recanalization rates following MOCA of the great and small saphenous veins. However, obesity was found to correlate with recanalization rates.

Missing Bullets: Bullet Embolization Case Series and Review of the Literature.

PURPOSE: Bullet embolization is a rare but dangerous phenomenon. Based on the location of embolization, migration of bullets can cause limb or intra-abdominal ischemia, pulmonary infarction, cardiac valve injury, or cerebrovascular accident. Bullet emboli can present a diagnostic challenge given the varied nature of complications based on location of embolization, which may not coincide with the site of initial injury. The purpose of this study is to present several cases of bullet embolization from our busy urban trauma center and make recommendations for management. METHODS: We present 3 cases of bullet embolization seen in injured patients at our Level 1 trauma center. We describe our management of these injuries and make recommendations for management in the context of our institutional experience and comment on the available literature regarding bullet embolization. RESULTS: Two of our patients presented in extremis and required operative intervention to achieve stability. The intravascular missile was discovered intraoperatively in one patient and removed in the operating room, while the missile was discovered on postoperative imaging in another patient and again removed operatively after an unsuccessful attempt at minimally invasive retrieval. Our third patient remained hemodynamically stable throughout his hospitalization and had endovascular management of his bullet embolus. CONCLUSION: Bullet emboli present a challenging complication of penetrating trauma. We recommend removal of all arterial bullet emboli and those within the pulmonary venous system. In hemodynamically stable patients, we recommend initial attempts of endovascular retrieval followed by open surgical removal. We recommend open removal in cases of hemodynamic instability.