Short-term outcomes of endovascular management of acute limb ischemia using aspiration mechanical thrombectomy.

OBJECTIVE: Management of acute limb ischemia (ALI) has seen greater utilization of catheter-based interventions over the last two decades. Data on their efficacy is largely based on comparisons of catheter-directed thrombolysis (CDT) and open thrombectomy. During this time, many adjuncts to CDT have emerged with different mechanisms of action, including pharmacomechanical thrombolysis (PMT) and aspiration mechanical thrombectomy (AMT). However, the safety and efficacy of newer adjuncts like AMT have not been well established. This study is a retrospective analysis of the contemporary management of ALI comparing patients treated with aspiration mechanical thrombectomy to patients treated with the more established CDT adjunct, pharmacomechanical thrombolysis. METHODS: Patients undergoing peripheral endovascular intervention for ALI using an adjunctive device were identified through query of the Vascular Quality Initiative (VQI) Peripheral Vascular Intervention (PVI) module from 2014 to 2019. Patients with a nonviable extremity (Rutherford ALI Stage 3), prior history of ipsilateral major amputation, popliteal aneurysm, procedures that were deemed elective (>72 h from admission), procedures that did not utilize an endovascular adjunctive device, and patients without short-term follow-up were all excluded from analysis. The primary outcome was a composite outcome of freedom from major amputation and/or death in the perioperative time period. RESULTS: We identified 528 patients with Rutherford ALI Stage 1 or 2 who were treated with an endovascular adjunct. 433 patients did not undergo aspiration mechanical thrombectomy (no AMT group) and 95 patients did undergo aspiration mechanical thrombectomy (AMT group). The amputation-free survival across all patients was 93.4%. There were significant differences in demographic, comorbidity, and treatment variables between groups (e.g., gender, prior percutaneous coronary intervention (PCI), history of prior peripheral artery disease intervention, and history of prior infra-inguinal PVI), so a propensity score matched analysis was included to account for these group differences. In the propensity score matched analysis, there was no significant difference in major amputation (AMT 7.4% vs no AMT 3.2%, p = 0.13) or death (AMT 95.8% survival vs no AMT 98.4% survival, p = 0.23) with the use of aspiration mechanical thrombectomy. However, there was significantly worse amputation-free survival with the use of aspiration mechanical thrombectomy (AMT 88.4% vs no AMT 95.3%, p = 0.03). On multivariate analysis, prior supra-inguinal bypass (OR 4.85, 1.70-13.84, p = 0.003), Rutherford ALI Stage 2B (OR 3.13, 1.47-6.67, p = 0.003), and aspiration mechanical thrombectomy (OR 2.71, 1.03-7.17, p = 0.05) were associated with the composite outcome. CONCLUSIONS: Short-term amputation-free survival rates of endovascular management of acute limb ischemia are adequate across all modalities. However, aspiration mechanical thrombectomy was associated with significantly worse amputation-free survival compared to other endovascular adjuncts alone (i.e., pharmacomechanical thrombolysis). Severe limb ischemia (Rutherford ALI Stage 2B) and prior supra-inguinal bypass were associated with worse amputation-free survival regardless of the choice of endovascular intervention.

Antegrade Superficial Femoral Artery Access for Lower Extremity Arterial Disease Is Safe and Effective in the Outpatient Setting.

BACKGROUND: Antegrade superficial femoral artery (SFA) access for peripheral artery disease reduces the time, radiation, and contrast required with contralateral common femoral access (CFA). Yet, this technique remains underutilized in the treatment of SFA, popliteal and tibial disease, and there remains limited data on the safety and effectiveness of antegrade SFA access in the outpatient setting. METHODS: A retrospective review of lower extremity peripheral arterial interventions in our office-based endovascular suite was conducted from 2013 to 2018. Interventions necessitating CFA access such as iliac, common femoral, or deep femoral artery revascularization were excluded (n = 206). In addition, interventions potentially requiring large sheaths not amenable to SFA access (e.g., popliteal aneurysm) were excluded. Relevant demographic and treatment variables including postoperative complications were abstracted. RESULTS: We identified 718 patients, who underwent revascularization of the SFA, popliteal and tibial arteries. Antegrade SFA access was chosen in 448 patients (62.4%) with the remaining 270 patients having retrograde CFA access. Antegrade SFA access was achieved primarily with a 4-French sheath, while a majority of retrograde CFA interventions utilized a 6-French sheath for access (87.7% vs 69.5%, P < 0.001). Significantly less fluoroscopy (9.5 vs 16.4 min, P < 0.001) and contrast (25.4 vs 38.5 mL, P < 0.001) were used during SFA access compared with retrograde access. Technical success was achieved in 93.2% with antegrade SFA vs 94.8% retrograde CFA access (P = 0.42). The overall rate of complications was low for both cohorts (2.7% vs 3.7%, P = 0.78) and there were no statistical differences in access site complications (1.1% vs 1.5%, P = 0.94), hematoma (0.7% vs 1.1%, P = 0.84), and pseudoaneurysm (0.4% vs 0%, P = 0.98) between techniques. CONCLUSIONS: Percutaneous antegrade SFA access can be performed safely in the outpatient setting and remains an effective alternative to retrograde CFA access with significantly less utilization of fluoroscopy and contrast.

Presentation and Management of Arterial Thromboembolisms during Active Inflammatory Bowel Disease: Case Series and Literature Review.

BACKGROUND: Active inflammatory bowel disease (IBD) is associated with considerable risk for thromboembolism; however, arterial thromboembolism is rare and associated with considerable morbidity and mortality. Their management requires careful coordination between multiple providers, and as a consequence, much of the published literature is limited to case reports published across specialties. METHODS: We examined our recent institutional experience with aortoiliac, mesenteric, and peripheral arterial thromboembolisms in patients with either Crohn's disease or ulcerative colitis. To supplement our experience, a comprehensive literature review was performed using MEDLINE and EMBASE databases from 1966 to 2019. Patient demographics, flare/thromboembolism management, and outcomes were abstracted from the selected articles and our case series. RESULTS: Fifty-two patients with IBD, who developed an arterial thromboembolism, were identified (49 from published literature and 3 from our institution). More than 82% of patients presented during an active IBD flare. Surgical intervention was attempted in 77% of patients, which included open thromboembolectomy, catheter-directed thrombolysis, or bowel resection. Thromboembolism resolution was achieved in 76% of patients with comparable outcomes with either catheter-directed thrombolysis or open thrombectomy (83.3% vs. 68.2%). Nearly one-third of patients underwent small bowel resection or colectomy. In 2 patients, thromboembolism resolution was achieved only after total abdominal colectomy for severe pancolitis. Multiple thromboembolectomies were associated with higher risk for amputation. Overall mortality was 11.5% but was greatest for occlusive aortoiliac and mesenteric thromboembolism (14.3% and 57%, respectively). All survivors of occlusive superior mesenteric artery thromboembolism suffered short gut syndrome requiring small bowel transplant. CONCLUSIONS: Patients with IBD, who develop an arterial thromboembolism, can expect overall poor outcomes. Catheter-directed thrombolysis achieved comparable outcomes with open thromboembolectomy without undue bleeding risk. Total abdominal colectomy for moderate-to-severe pancolitis is an emerging strategy in the management of refractory arterial thromboembolism. Successful surgical management may include open thromboembolectomy, catheter-directed thrombolysis, and bowel resection when indicated.

Initial experiences with point-of-care rapid thrombelastography for management of life-threatening postinjury coagulopathy.

BACKGROUND: Massive transfusion (MTP) protocol design is hindered by lack of accurate assessment of coagulation. Rapid thrombelastography (r-TEG) provides point-of-care (POC) analysis of clot formation. We designed a prospective study to test the hypothesis that integrating TEG into our MTP would facilitate goal-directed therapy and provide equivalent outcomes compared to conventional coagulation testing. STUDY DESIGN AND METHODS: Thiry-four patients who received more than 6 units of red blood cells (RBCs)/6 hours who were admitted to our Level 1 trauma center after r-TEG implementation (TEG) were compared to 34 patients admitted prior to TEG implementation (Pre-TEG). Data are presented as mean±SEM. RESULTS: Emergency department pre-TEG versus TEG shock, and coagulation indices, were not different: systolic blood pressure (94 mmHg vs. 101 mmHg), temperature (35.3°C vs. 35.9°C), pH (7.16 vs. 7.11), base deficit (-13.0 vs. -14.7), lactate (6.5 vs. 8.1), international normalized ratio (INR; 1.59 vs. 1.83), and partial thromboplastin time (48.3 vs. 57.9). Although not significant, patients with Injury Severity Score range 26 to 35 were more frequent in the pre-TEG group. Fresh-frozen plasma (FFP):RBCs, platelets:RBCs, and cryoprecipitate (cryo):RBC ratios were not significantly different at 6 or 12 hours. INR at 6 hours did not discriminate between survivors and nonsurvivors (p=0.10), whereas r-TEG "G" value was significantly associated with survival (p=0.03), as was the maximum rate of thrombin generation (MRTG; mm/min) and total thrombin generation (TG; area under the curve) (p=0.03 for both). Patients with MRTG of more than 9.2 received significantly less components of RBCs, FFP, and cryo (p=0.048, p=0.03, and p=0.04, respectively). CONCLUSION: Goal-directed resuscitation via r-TEG appears useful for management of trauma-induced coagulopathy. Further experience with POC monitoring could result in more efficient management leading to a reduction of transfusion requirements.

Hepatorenal syndrome from an ilio-iliac arteriovenous fistula: A rare complication from an endoleak.

Arteriovenous fistula is a rare and often unrecognized complication of aneurysms, with a varied and frequently inconsistent presentation. We present the case of an ilio-iliac arteriovenous fistula formation in a 71-year-old man associated with a type III endoleak after endovascular iliac branch repair. Because of rapidly progressing congestive heart failure and hepatorenal syndrome, we performed urgent endovascular repair with successful endoleak exclusion. After the procedure, the patient demonstrated a remarkably rapid and complete recovery.

Primary fibrinolysis is integral in the pathogenesis of the acute coagulopathy of trauma.

BACKGROUND: The existence of primary fibrinolysis (PF) and a defined mechanistic link to the "Acute Coagulopathy of Trauma" is controversial. Rapid thrombelastography (r-TEG) offers point of care comprehensive assessment of the coagulation system. We hypothesized that postinjury PF occurs early in severe shock, leading to postinjury coagulopathy, and ultimately hemorrhage-related death. METHODS: Consecutive patients over 14 months at risk for postinjury coagulopathy were stratified by transfusion requirements into massive (MT) >10 units/6 hours (n = 32), moderate (Mod) 5 to 9 units/6 hours (n = 15), and minimal (Min) <5 units/6 hours (n = 14). r-TEG was performed by adding tissue factor to uncitrated whole blood. r-TEG estimated percent lysis was categorized as PF when >15% estimated percent lysis was detected. Coagulopathy was defined as r-TEG clot strength = G < 5.3 dynes/cm. Logistic regression was used to define independent predictors of PF. RESULTS: A total of 34% of injured patients requiring MT had PF, which was associated with lower emergency department systolic blood pressure, core temperature, and greater metabolic acidosis (analysis of variance, P < 0.0001). The risk of death correlated significantly with PF (P = 0.026). PF occurred early (median, 58 minutes; interquartile range, 1.2-95.9 minutes); every 1 unit drop in G increased the risk of PF by 30%, and death by over 10%. CONCLUSIONS: Our results confirm the existence of PF in severely injured patients. It occurs early (<1 hour), and is associated with MT requirements, coagulopathy, and hemorrhage-related death. These data warrant renewed emphasis on the early diagnosis and treatment of fibrinolysis in this cohort.

Percutaneous mechanical thrombectomy of lower extremity deep vein thrombosis in a pediatric patient.

Deep vein thrombosis is relatively rare in the pediatric setting, though it carries significant risk for pulmonary embolism and post-thrombotic syndrome. We report a case of a 10-year-old girl diagnosed with pulmonary embolism and right iliofemoral vein deep vein thrombosis with concomitant granulomatosis with polyangiitis (formerly Wegener's granulomatosis) and acute glomerulonephritis. Owing to lifestyle-limiting venous claudication, we performed percutaneous, mechanical thrombectomy using the ClotTriever system with successful removal of likely both acute and chronic thrombus. After the procedure, the patient had near complete resolution of her venous claudication symptoms.

Arterial thromboembolism associated with COVID-19 and elevated D-dimer levels.

The novel coronavirus 2019 (SARS-CoV-2) was first identified in January 2020 and has since evolved into a pandemic affecting >200 countries. The severity of presentation is variable and carries a mortality between 1% and 3%. We continue to learn about the virus and the resulting acute respiratory illness and hypercoagulability; however, much remains unknown. In our early experience in a high-volume center, we report a series of four cases of acute peripheral artery ischemia in patients with COVID-19 in the setting of elevated D-dimer levels.

Noncitrated whole blood is optimal for evaluation of postinjury coagulopathy with point-of-care rapid thrombelastography.

INTRODUCTION: Progressive postinjury coagulopathy has become the fundamental rationale for damage control surgery, and the decision to abort operative intervention must occur prior to overt laboratory confirmation of coagulopathy. Current coagulation testing is most commonly performed for monitoring anticoagulation therapy, the results are delayed, and the applicability of these tests in the trauma setting is questionable. Point-of-care (POC) rapid thrombelastography (r-TEG) provides real time analysis of thrombostatic function, which may allow for accurate, goal directed therapy. The test differs from standard thrombelastography (TEG) because the clotting process and subsequent analysis is accelerated by the addition of tissue factor to the whole blood sample, but is limited by the requirement that the analysis be performed within 4 min of blood draw to prevent clot formation. Consequently, citrated specimens have been proposed to obviate this time limitation. We hypothesized that the speed of r-TEG analysis following tissue factor addition to citrated blood might compromise accurate determinations compared with noncitrated whole blood. Additionally, we sought to compare the use of r-TEG with conventional coagulation tests in analysis of postinjury coagulopathy. METHODS: We conducted a retrospective study of severely injured patients entered into our trauma database between January and June 2008 who were at risk for postinjury coagulopathy. Patients needed simultaneous conventional coagulation (INR, fibrinogen, platelet count) and r-TEG specimens with either fresh or citrated whole blood for inclusion in the study. kappa-Statistics were used to determine the agreement between the tests in predicting hypocoagulability. McNemar's chi(2) tests were used to compare theoretical blood product administration between r-TEG and conventional coagulation tests for noncitrated specimens. Therapeutic transfusion triggers were: INR (>1.5) and r-TEG ACT (>125 s) for FFP administration; fibrinogen (<133 mg/dL) and alpha-angle (<63 degrees ) for cryoprecipitate; and platelet count (<100K) and maximum amplitude (MA) (<52 mm) for aphaeresis platelets. Statistical significance was established as P<0.05 using two-sided tests. RESULTS: Forty-four patients met the inclusion criteria. kappa-Values (correlation) were higher in noncitrated versus citrated specimens for all comparisons between conventional and r-TEG tests, indicating better performance of r-TEG with the noncitrated specimens. FFP would have been administered to significantly more patients based on conventional transfusion triggers (61.5% by INR transfusion triggers versus 26.9% by r-TEG-ACT triggers, P=0.003). There was no statistically significant difference in potential cryoprecipitate or aphaeresis platelet administration. CONCLUSION: POC r-TEG is superior when performed with uncitrated versus citrated whole blood for evaluation of postinjury coagulation status. As a real time measure of total thrombostatic function, our preliminary data suggest that r-TEG may effectively guide transfusion therapy and result in reduced FFP administration compared with conventional coagulation tests.

Defining a Research Agenda for Patient-Reported Outcomes in Surgery: Using a Delphi Survey of Stakeholders.

Importance: Identifying timely and important research questions using relevant patient-reported outcomes (PROs) in surgery remains paramount in the current medical climate. The inaugural Patient-Reported Outcomes in Surgery (PROS) Conference brought together stakeholders in PROs research in surgery with the aim of creating a research agenda to help determine future directions and advance cross-disciplinary collaboration. Objective: To create a research agenda to help determine future directions and advance cross-disciplinary collaboration on the use of PROs in surgery. Design, Setting, and Participants: An iterative web-based interface was used to create a conference-based, modified Delphi survey for registrants at the PROS Conference (January 29-30, 2015), including surgeons, PRO researchers, payers, and other stakeholders. In round 1, research items were generated from qualitative review of responses to open-ended prompts. In round 2, items were ranked using a 5-point Likert scale; attendees were also asked to submit any new items. In round 3, the top 30 items and newly submitted items were redistributed for final ranking using a 3-point Likert scale. The top 20 items by mean rating were selected for the research agenda. Main Outcomes and Measures: An expert-generated research agenda on PROs in surgery. Results: Of the 143 people registered for the conference, 137 provided valid email addresses. There was a wide range of attendees, with the 3 most common groups being plastic surgeons (28 [19.6%]), general surgeons (19 [13.3%]), and researchers (25 [17.5%]). In round 1, participants submitted 459 items, which were reduced through qualitative review to 53 distinct items across 7 themes of PROs research. A research agenda was formulated after 2 successive rounds of ranking. The research agenda identified 3 themes important for future PROs research in surgery: (1) PROs in the decision-making process, (2) integrating PROs into the electronic health record, and (3) measuring quality in surgery with PROs. Conclusions and Relevance: The PROS Conference research agenda was created using a modified Delphi survey of stakeholders that will help researchers, surgeons, and funders identify crucial areas of future PROs research in surgery.

Viscoelastic clot strength predicts coagulation-related mortality within 15 minutes.

BACKGROUND: Predicting refractory coagulopathy early in resuscitation of injured patients may decrease a leading cause of preventable death. We hypothesized that clot strength (G) measured by point-of-care rapid thrombelastography (r-TEG) on arrival in the emergency department can predict massive transfusion (MT) and coagulation-related mortality (MT-death). METHODS: Trauma alerts/activations from May 2008 to September 2010 were reviewed. The variables included the following: age, sex, injury severity score (ISS), systolic blood pressure (SBP), base deficit (BD), traditional coagulation tests (international normalized ratio ([INR], partial thromboplastin time [PTT]), TEG-derived G, and blood products transfused within the first 6 hours. Independent predictors of 2 outcomes (MT [≥10 packed red blood cells units/6 h] and MT-related death) were identified using logistic regression. The individual predictive values of BD, INR, PTT, and G were assessed comparing the areas under the receiver operating characteristic curves (AUC ROC), while adjusting for age, ISS, and SBP. RESULTS: Among the 80 study patients, 48% required MT, and 21% died of MT-related complications. INR, ISS, and G were independent predictors of MT, whereas age, ISS, SBP, and G were independently associated with MT-death. The predictive power for outcome MT did not differ among INR (adjusted AUC ROC = 0.92), PTT (AUC ROC = 0.90, P = .41), or G (AUC ROC = 0.89, P = .39). For outcome MT-death, G had the greatest adjusted AUC ROC (0.93) compared with the AUC ROC for BD (0.87, P = .05), INR (0.88, P = .11), and PTT (0.89; P = .19). CONCLUSION: These data suggest that the point-of-care TEG parameter clot strength (G) provides consistent, independent prediction of MT and MT-death early in the resuscitation of injured patients.

Rapid thrombelastography (r-TEG) identifies hypercoagulability and predicts thromboembolic events in surgical patients.

BACKGROUND: Despite routine prophylaxis, thromboembolic events (TEs) in surgical patients remain a substantial problem. Furthermore, the timing and incidence of hypercoagulability, which predisposes to these events is unknown, with institutional screening programs serving primarily to establish a diagnosis after an event has occurred. Emerging evidence suggests that point of care (POC) rapid thrombelastography (r-TEG) provides a real-time analysis of comprehensive thrombostatic function, which represents an analysis of both enzymatic and platelet components of thrombus formation. We hypothesized that r-TEG can be used as a screening tool to identify hypercoagulable states in surgical patients and would predict subsequent thromboembolic events. METHODS: Rapid thrombelastography r-TEG analyses were performed on 152 critically ill patients in the surgical intensive care unit (ICU) during 7 months. Hypercoagulability was defined as clot strength (G)>12.4 dynes/cm(2). Variables of interest for identifying hypercoagulability and thromboembolic events included sex, age, operating hospital service, specific injury patterns, injury severity score (ISS), transfusion within first 24 h, ICU duration of stay, ventilator days, hospital admission days, and thromboprophylaxis. Comparisons between the hypercoagulable and normal groups or between the groups with and without thromboembolic events were performed using Chi-square tests or the Fisher exact test for categorical variables and independent sample t tests or Wilcoxon rank sum tests for continuous variables. Multivariate logistic regression analysis (LR) was performed to identify independent predictors of thromboembolic events. A receiver operating characteristic curve was used to measure the performance of G for predicting the occurrence of a TE event. All tests were 2-sided with significance of P < .05. RESULTS: In all, 86 patients (67%) were hypercoagulable by r-TEG. More than 85% of patients in the hypercoagulable group and 79% in the normal group received thromboprophylaxis during the study period. The differences between hypercoagulable and normal groups by bivariate analysis included high-risk injuries (52% vs 35%; P = .03), spinal cord injury (27% vs 12%; P = .03), median ICU duration of stay (13 vs 7 days; P < .001), median ventilator days (6 vs 2; P < .001), and median hospital duration of stay (20 vs 13 days; P < .001). A total of 16 patients (19%) of the hypercoagulable group suffered a thromboembolic event, and 10 hypercoagulable patients (12%) had thromboembolic events predicted by prior r-TEG hypercoagulability. No patients with normal coagulability by r-TEG had an event (P < .001). LR analysis showed that the strongest predictor of TE after controlling for the presence of thromboprophylaxis was elevated G value (odds ratio: 1.25, 95% confidence interval [CI]: 1.12-1.39). For every 1 dyne/cm(2) increase in G, the odds of a TE increased by 25%. CONCLUSION: These results indicate that the presence of hypercoagulability identified by r-TEG is predictive of thromboembolic events in surgical patients. Subsequent study is necessary to define optimal prophylactic treatment strategies for patients with r-TEG proven hypercoagulability.