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Chronic venous disease is a worldwide problem associated with significant morbidity and is expected to increase in prevalence as the current population ages. This is a comprehensive review of the anatomy, pathophysiology, genomics, clinical classification, and treatment modalities of chronic venous disease.

Venous disease is a term that broadly covers both venous thromboembolic disease and chronic venous disease. The basic pathophysiology of venous thromboembolism and chronic venous disease differ as venous thromboembolism results from an imbalance of hemostasis and thrombosis while chronic venous disease occurs in the setting of tissue damage because of prolonged venous hypertension. Both diseases are common and account for significant mortality and morbidity, respectively, and collectively make up a large health care burden. Despite both diseases having well-characterized environmental components, it has been known for decades that family history is an important risk factor, implicating a genetic element to a patient’s risk. Our understanding of the pathogenesis of these diseases has greatly benefited from an expansion of population genetic studies from pioneering familial studies to large genome-wide association studies; we now have multiple risk loci for each venous disease. In this review, we will highlight the current state of knowledge on the epidemiology and genetics of venous thromboembolism and chronic venous disease and directions for future research.

The objective of this study was to assess patient, wound, care, and reflux characteristics of venous leg ulcers (VLUs) to update and improve knowledge on disease etiology, identify barriers to healing, and improve treatment.Patients diagnosed with venous leg ulcers treated at the Stanford Advanced Wound Care Center between 2018 to 2019 were identified from the Healogics iHeal database. We identified 327 VLU entries, of which 133 were patients that had multiple or recurring wounds. An additional 27 patients were labeled as misdiagnosis, resulting in a final patient sample of 167. Patient demographics, wound, care, and ultrasound data for these patients was extracted from the Stanford electronic medical records regarding characteristics. The initial data analysis suggested possible differences in VLU characteristics depending on patient age and BMI, which was then further analyzed.Of the 167 VLU patients assessed, 53.9% were male, and 46.1% were female. The mean age was 74.7 years, and the average body mass index (BMI) was 30.2 kg/mVLU pathology appears to differ depending on patient demographics and characteristics. Different drivers may influence disease cause, progression, and prognosis, making a standard approach to VLUs difficult. Our findings suggest that identifying different subtypes of VLUs and adapting an algorithm of care with a personalized treatment may help optimize management of these patients.

Chronic wounds affect roughly 6.5 million patients in the US annually. Current standard of therapy entails weekly sharp debridement. However, the sharp technique is associated with significant pain, while having minimal impact on the bioburden. Our study proposes the Er:YAG laser as an alternative method of debridement that may decrease procedural pain, reduce bioburden, and potentially improve overall healing. This pilot study was performed as a prospective, randomized, controlled, crossover clinical trial, containing two groups: (1) one group underwent single laser debridement session first, followed by single sharp debridement session one week later; and (2) the other group underwent single sharp debridement session first, followed by single laser debridement session one week later. Variables analyzed included pain during debridement, pre- and post-debridement wound sizes, pre- and post-debridement bacterial loads and patient preference. Twenty-two patients were enrolled (12 patients in Group 1, plus 10 patients in Group 2). The mean pain score for patients undergoing laser debridement was 3.0 ± 1.7 vs. 4.8 ± 2.6 for those undergoing sharp debridement (p = 0.003). The mean percent change in wound size 1-week post-laser debridement was -20.8% ± 80.1%, as compared with -36.7% ± 54.3% 1-week post-sharp debridement (p = 0.6). The percentage of patients who had a bacterial load in the low/negative category increased from 27.3% to 59.1% immediately after laser debridement (p = 0.04), vs. 54.5% to 68.2% immediately after sharp debridement (p = 0.38). Moreover, there was a sustained decrease in bacterial load 1-week post-laser debridement, as compared with no sustained decrease 1-week post-sharp debridement (p < 0.02). Overall, 52.9% of patients preferred laser debridement vs. 35.3% for sharp debridement. We believe that Er:YAG laser serves as a promising technology in chronic wounds, functioning as a potentially superior alternative to sharp debridement, the current standard of therapy.

We report an unusual case of a 53-year-old female presenting with symptoms of transient ischemic attack secondary to compression of the left internal carotid artery with mandible depression. Duplex ultrasound examination confirmed compression of the left internal carotid artery with mouth opening. Normally, the posterior belly of the digastric muscle contracts to induce mandible depression and opens the mouth; however, this muscle contraction motion caused compression on her internal carotid artery resulting in her symptoms.

Background: Varicose veins are a common problem with no approved medical therapies. Although it is believed that varicose vein pathogenesis is multifactorial, there is limited understanding of the genetic and environmental factors that contribute to their formation. Large-scale studies of risk factors for varicose veins may highlight important aspects of pathophysiology and identify groups at increased risk for disease. Methods: We applied machine learning to agnostically search for risk factors of varicose veins in 493 519 individuals in the UK Biobank. Predictors were further studied with univariable and multivariable Cox regression analyses (2441 incident events). A genome-wide association study of varicose veins was also performed among 337 536 unrelated individuals (9577 cases) of white British descent, followed by expression quantitative loci and pathway analyses. Because height emerged as a new candidate risk factor, we performed mendelian randomization analyses to assess a potential causal role for height in varicose vein development. Results: Machine learning confirmed several known (age, sex, obesity, pregnancy, history of deep vein thrombosis) and identified several new risk factors for varicose vein disease, including height. After adjustment for traditional risk factors in Cox regression, greater height remained independently associated with varicose veins (hazard ratio for upper versus lower quartile, 1.74; 95% CI, 1.51–2.01; P P =2.07×10 −16 ). Conclusions: Using data from nearly a half-million individuals, we present a comprehensive genetic and epidemiological study of varicose veins. We identified novel clinical and genetic risk factors that provide pathophysiological insights and could help future improvements of treatment of varicose vein disease.

Summary: Background: There is ample evidence to show that supervised exercise is efficacious and cost effective for improving claudication symptoms in patients with peripheral artery disease (PAD). Home based exercise therapy can be an effective alternative to supervised exercise however, the results of this is variable depending on the level of motivation and engagement of the patient. Patients and methods: We performed a pilot study in 41 patients to determine whether a home based exercise program with the use of an activity tracking device with personalized feedback and financial incentives can increase daily activity, improve walking and sustain engagement in the exercise regimen in patients with PAD. In this randomized pilot study, the patients in the study group were fitted with an activity monitoring device and given behavioral monitoring, motivational updates and feedback regarding their exercise program. This study group was further divided in to two groups. One half of these patients in the study group were also given financial incentives if they reached their set targets. The control group wore the device with no feedback or ability to see their number of steps walked. Results: Results showed that at the end of the 12 week period, patients in the study groups walked more compared to the controls and the financial incentive structure resulted in an additional 38–63% increase in average daily steps. Conclusions: This pilot study revealed that a home-based exercise program with activity monitoring, feedback and financial incentives resulted increased daily steps, 6-minute walking distance and overall compliance with the program in PAD patients with claudication.

This national cohort study examines changes in the number of vascular surgical procedures completed in the US before and during the COVID-19 pandemic.

Varicose veins are a common problem with no approved medical therapies. Although it is believed that varicose vein pathogenesis is multifactorial, there is limited understanding of the genetic and environmental factors that contribute to their formation. Large-scale studies of risk factors for varicose veins may highlight important aspects of pathophysiology and identify groups at increased risk for disease.We applied machine learning to agnostically search for risk factors of varicose veins in 493 519 individuals in the UK Biobank. Predictors were further studied with univariable and multivariable Cox regression analyses (2441 incident events). A genome-wide association study of varicose veins was also performed among 337 536 unrelated individuals (9577 cases) of white British descent, followed by expression quantitative loci and pathway analyses. Because height emerged as a new candidate risk factor, we performed mendelian randomization analyses to assess a potential causal role for height in varicose vein development.Machine learning confirmed several known (age, sex, obesity, pregnancy, history of deep vein thrombosis) and identified several new risk factors for varicose vein disease, including height. After adjustment for traditional risk factors in Cox regression, greater height remained independently associated with varicose veins (hazard ratio for upper versus lower quartile, 1.74; 95% CI, 1.51-2.01; P0.0001). A genome-wide association study identified 30 new genome-wide significant loci, identifying pathways involved in vascular development and skeletal/limb biology. Mendelian randomization analysis provided evidence that increased height is causally related to varicose veins (inverse-variance weighted: odds ratio, 1.26; P=2.07×10Using data from nearly a half-million individuals, we present a comprehensive genetic and epidemiological study of varicose veins. We identified novel clinical and genetic risk factors that provide pathophysiological insights and could help future improvements of treatment of varicose vein disease.

Background: Varicose veins are a common problem with no approved medical therapies. While it is believed that varicose vein pathogenesis is multifactorial, there is a limited understanding of the genetic and environmental factors that contribute to their formation. Large-scale studies of risk factors for varicose veins may highlight important aspects of pathophysiology and identify groups at increased risk for disease. Methods: We applied machine learning to agnostically search for risk factors of varicose veins in 493,519 individuals in the UK Biobank. Predictors were further studied using univariable and multivariable Cox regression analysis. A genome-wide association study (GWAS) of varicose veins was also performed among 337,536 individuals (9,577 cases) of white British descent, followed by eQTL and pathway analyses. Because height emerged as a new candidate predictor, we used LD score regression to estimate the genetic correlation between height and varicose veins. Finally, we performed Mendelian randomization analyses to assess for a causal role for height in varicose vein disease. Results: Machine learning confirmed several known (age, gender, obesity, pregnancy, history of deep vein thrombosis) and identified several new risk factors for varicose vein disease. The most important novel predictors were leg bioimpedance (HR: 0.44, 95% CI: 0.39-0.50, P < 0.0001) and height (HR: 1.74; 95% CI: 1.51-2.01, P < 0.0001), which both remained independently associated with varicose veins after adjusting for traditional risk factors in Cox regression. A GWAS identified 30 new genome-wide significant loci, identifying pathways involved in vascular development and skeletal/limb biology. Mendelian randomization analysis provided evidence that increased height is causally related to varicose veins (IVW: beta = 0.266, P = 1.28 x 10 -16 ). Conclusions: Using data from nearly half a million individuals, we identified novel clinical and genetic risk factors which provide pathophysiological insights and could help future improvements of treatment of varicose vein disease.

Lymphedema, especially in the early stages, can easily be confused with venous edema which is one of the most common causes of lower extremity swelling. Lymphedema and venous edema can occur separately or concurrently as the lymph system and venous system are mutually complimentary and the pathophysiologies of these conditions are intricately entwined. This chapter will focus on ways to differentiate edema of the lymph and venous origin in the lower extremity.

ImportanceHeart failure constitutes a high burden on patients and society, but although lifetime risk is high, it is difficult to predict without costly or invasive testing. Knowledge about novel risk factors could enable early diagnosis and possibly preemptive treatment.ObjectiveTo establish new risk factors for heart failure.DesignWe applied supervised machine learning in UK Biobank in an agnostic search of risk factors for heart failure. Novel predictors were then subjected to several in-depth analyses, including multivariable Cox models of incident heart failure, and assessment of discrimination and calibration.SettingPopulation-based cohort study.Participants500,451 individuals who volunteered to participate in the UK Biobank cohort study, excluding those with prevalent heart failure.Exposure3646 variables reflecting different aspects of lifestyle, health and disease-related factors.Main OutcomeIncident heart failure hospitalization.ResultsMachine learning confirmed many known and putative risk factors for heart failure, and identified several novel candidates. Mean reticulocyte volume appeared as one novel factor, and leg bioimpedance another; the latter appearing as the most important new factor. Leg bioimpedance was significantly lower in those who developed heart failure (p=1.1x10-72) during up to 9.8-year follow-up. When adjusting for known heart failure risk factors, leg bioimpedance was inversely related to heart failure (hazard ratio [95%CI], 0.60 [0.48–0.73]) and 0.75 [0.59–0.94], in age- and sex-adjusted and fully adjusted models, respectively, comparing the upper vs. lower quartile). A model including leg bioimpedance, age, sex, and self-reported history of myocardial infarction showed good predictive capacity of future heart failure hospitalization (C-index=0.82) and good calibration.Conclusions and RelevanceLeg bioimpedance is inversely associated with heart failure incidence in the general population. A simple model of exclusively non-invasive measures, combining leg bioimpedance with history of myocardial infarction, age, and sex provides accurate predictive capacity.Key pointsQuestionWhich are the most important risk factors for incident heart failure?FindingsIn this population-based cohort study of ~500,000 individuals, machine learning identified well-established risk factors, but also several novel factors. Among the most important were leg bioimpedance and mean reticulocyte volume. There was a strong inverse relationship between leg bioimpedance and incident heart failure, also in adjusted analyses. A model entailing leg bioimpedance, age, sex, and self-reported history of myocardial infarction showed good predictive capacity of heart failure hospitalization and good calibration.MeaningLeg bioimpedance appears to be an important new factor associated with incident heart failure.

Background Recent reports demonstrate high diagnostic accuracy of lung ultrasound for evaluation of dyspnea. We assessed the feasibility of training internal medicine residents in lung ultrasound with a pocket ultrasound device. Methods We performed a prospective, observational trial of residents performing lung ultrasound with a pocket ultrasound. Training consisted of two 90-minute sessions of didactics and supervised bedside performance. Two residents received an additional 2 weeks of training. Residents recorded a clinical diagnosis based on admission data. Following lung ultrasound performance, an ultrasound diagnosis was recorded integrating clinical and sonographic findings. Using receiver operating curve analysis, the area under the curve was calculated for both clinical diagnosis and ultrasound diagnosis using attending physician's final discharge diagnosis as the gold standard. Results Five residents performed 69 exams. The AUC for ultrasound diagnosis was significantly higher than that for clinical diagnosis (0.87 vs 0.81, P Conclusions Lung ultrasound performed by residents with a pocket ultrasound improved the diagnostic accuracy of dyspnea. Two residents undergoing extended training showed a total increase in diagnostic accuracy.

Chronic leg ulcers (as differentiated from wound of the foot) are most often due to venous disease, arterial insufficiency (peripheral arterial disease), or a combination of both. Treatment modalities vary depending on the etiology of the ulcer, so it is important to make an appropriate diagnosis of the wound. Like for most medical illnesses, the determination of the etiology of these wounds is based on history, physical examination, and testing.

Heparin-induced thrombocytopenia (HIT) is an unpredictable reaction to heparin characterized by thrombocytopenia and increased risk of life-threatening venous and/or arterial thrombosis. Data are lacking regarding additional risk factors that may be associated with the development of HIT. This study aimed to identify the risk factors that may be associated with HIT in medical inpatients receiving heparin. Twenty five thousand six hundred and fifty-three patients admitted to the medicine service who received heparin product were reviewed retrospectively. The diagnosis of HIT was confirmed if the platelet count dropped >50% from baseline and there was a positive laboratory HIT assay. Fifty-five cases of in-hospital HIT were observed. Multivariate analysis identified the administration of full anticoagulation dose with unfractionated heparin or exposure to heparin products for more than 5 d with an increased risk of HIT. Moreover, patients who were on haemodialysis, carried a diagnosis of autoimmune disease, gout or heart failure were also at increased risk. The results suggest that when using heparin products in these patient cohorts, increased surveillance for HIT is necessary.

Summary The superficial inferior epigastric artery (SIEA) flap consists of skin and subcutaneous fat with limited donor-site morbidity and has the potential to be very versatile – either as a thin flap without excessive fat tissue or as a voluminous flap for breast reconstruction. However, anatomical inter-individual variability often makes the choice of a free SIEA flap difficult. Imaging of small-calibre vessels is possible with the multi-detector-row computed tomography angiography (MDCTA) and to obtain the characteristics of the superficial inferior epigastric vascular anatomy, we investigated the superficial inferior epigastric system using MDCTA. Methods We investigated 17 patients who had abdominal wall MDCTA in preparation for a free flap procedure using either the deep inferior epigastric perforator (DIEP), SIEA or the groin flap. The visibility and anatomical characteristics including the branching pattern, the diameter, course of travel and layers were noted. Results The SIEA was visible in 64.7% and, of these, 36.4% had a common trunk formation with the superficial circumflex iliac artery (SCIA), while 63.6% arose independently. The measured diameters were SIEA 1.6±0.4mm, SCIA 1.4±0.4mm, deep circumflex iliac artery (DCIA) 2.4±0.4mm, DIEA 2.9±0.4mm and superficial inferior epigastric vein (SIEV) 3.1±0.5mm. The SIEA consistently coursed lateral to and deeper than the SIEV and also lateral to the DIEA. Conclusion MDCTA provided detailed three-dimensional information of the superficial inferior epigastric vascular system including the course and size of the SIEA. The information on vascular anatomy obtained with the MDCTA is valuable in the preoperative planning of the free SIEA flap and should be performed routinely.

Summary Background In harvesting free fibula composite flaps, preoperative knowledge of the lower limb vascular anatomy is essential to prevent ischaemic complications or flap failure. Magnetic resonance angiography (MRA) allows imaging of the septocutaneous perforators (≤1–2mm diameter) of the peroneal artery used in the free fibula flap. Methods We investigated seven patients undergoing the free fibula flap preoperatively with high-resolution MRA images to study the following: 1) tibio-peroneal anatomy, 2) peripheral artery disease, 3) the positions of the perforator vessels on the peroneal artery and their course in the posterolateral intermuscular septum and 4) the cutaneous distribution of the perforators, and to compare them to surgical findings. Results MRA demonstrated tibio-peroneal anatomy in sufficient detail to exclude anatomic variants and significant peripheral vascular disease, detected septocutaneous perforators arising from the peroneal artery coursing in the posterolateral intermuscular septum and determined the skin terminus of the septocutaneous perforators. All septocutaneous perforators found during surgery were detected prospectively on high-resolution MRA. Conclusion Lower leg vascular anatomy assessment with high-resolution MRA determined the location of the septocutaneous perforators of the peroneal artery preoperatively with accuracy and precision. This anatomical knowledge provides for a safer procedure and the opportunity to plan surgical details preoperatively.

Background: Disruption of venous outflow can lead to tissue necrosis. Thrombosis of a venous channel at the coaptation site in instances of free tissue transfer could cause death of the transplanted tissues. Although various techniques have been used to monitor the viability of transferred tissues, there has been no technique designed specifically to check the flow within and the patency of the venous channel. The authors have devised an approach with which to monitor the changes in venous pressure in a composite tissue transferred by means of microsurgical technique for bodily reconstruction. Methods: The status of the venous system in various composite tissue grafts was monitored at the time of surgery or for 3 days after the completion of surgery by placing a small-caliber catheter in the vein within the transferred tissue. A total of 52 patients participated in the study. Results: The venous pressure noted in grafts with a patent venous channel remained constant within a range between 0 and 35 mmHg. Venous insufficiency was detected in three of the 52 cases, with unmistakable findings of an elevated venous pressure of over 50 mmHg. Conclusions: The technique of measuring the venous pressure by means of an indwelling venous catheter to monitor changes was found to accurately assess the patency of the venous channel and, by inference, the viability of the transferred tissue. No morbidity was associated with the technique.

Recent refinements of magnetic resonance angiography (MRA) allow imaging vessels as small as the septocutaneous perforators (< or = 1 to 2 mm diameter), but a Medline review reveals no report of septocutaneous vessel imaging for free flap surgery. Challenges in fibula free flap preparation include knowledge of: (1) tibioperoneal anatomy, (2) the positions of the perforator vessels on the peroneal artery and their course in the posterolateral intermuscular septum, and (3) the cutaneous distribution of the perforators. Questioning whether high-resolution MRA could image these, we studied the lower extremities of nine healthy volunteers. MRA demonstrated tibioperoneal anatomy in sufficient detail to exclude anatomic variants and significant peripheral vascular disease and showed septocutaneous perforators arising from the peroneal artery and coursing in the posterolateral intermuscular septum to the skin. High-resolution MRA provided anatomic and clinical information that conventionally has been impossible to obtain preoperatively or has required multiple tests, often of an invasive nature.

The primary aim of the present study was to determine the cumulative effect of a set of peripheral artery disease (PAD) risk factors among age, gender and race/ethnicity groups in the United States.We examined data from a nationally representative sample of the US population (National Health and Nutrition Examination Survey [NHANES], 1999-2004). A total of 7058 subjects 40 years or older that completed the interview, medical examination and had ankle-brachial index (ABI) measurements were included in this study.The age- and sex-standardized prevalence of PAD was 4.6 % (standard error [SE] 0.3%).The highest prevalence of PAD was observed among elderly, non-Hispanic Blacks and women. In a multivariable age-, gender- and race/ethnicity-adjusted model hypertension, diabetes, chronic kidney disease, and smoking were retained as PAD risk factors (p ≤ 0.05 for each). The odds of PAD increased with each additional risk factor present from a non-significant 1.5-fold increase (O.R 1.5, 95% confidence interval [CI] 0.9-2.6) in the presence of one risk factor, to more than ten-fold (OR 10.2, 95% CI 6.4-16.3) in the presence of three or more risk factors. In stratified analysis, non-Hispanic Blacks (OR 14.7, 95% CI 2.1-104.1) and women (OR 18.6, 95% CI 7.1-48.7) were particularly sensitive to this cumulative effect.In a large nationally representative sample, an aggregate set of risk factors that included diabetes mellitus, chronic kidney disease, hypertension and smoking significantly increase the likelihood of prevalent PAD. A cumulative risk factor analysis highlights important susceptibility differences among different population groups and provides additional evidence to redefine screening strategies in PAD.

Heparin-induced thrombocytopenia (HIT) is an unpredictable reaction to heparin characterized by thrombocytopenia and increased risk of life-threatening venous and/or arterial thrombosis. Data are lacking regarding additional risk factors that may be associated with the development of HIT. This study aimed to identify the risk factors that may be associated with HIT in medical inpatients receiving heparin. Twenty five thousand six hundred and fifty-three patients admitted to the medicine service who received heparin product were reviewed retrospectively. The diagnosis of HIT was confirmed if the platelet count dropped50% from baseline and there was a positive laboratory HIT assay. Fifty-five cases of in-hospital HIT were observed. Multivariate analysis identified the administration of full anticoagulation dose with unfractionated heparin or exposure to heparin products for more than 5 d with an increased risk of HIT. Moreover, patients who were on haemodialysis, carried a diagnosis of autoimmune disease, gout or heart failure were also at increased risk. The results suggest that when using heparin products in these patient cohorts, increased surveillance for HIT is necessary.

A case of granular cell tumor (GCT) was reported. We encountered a 33-year-old woman with a painless, elastic, hard mass in the soft tissue of the suprasternal space. The tumor was excised with several millimeters margin of normal tissue above the deep cervical fascia and the wound was closed primarily. Histological examination on hematoxylin-eosin stain showed a tumor growth in the mid- to deep dermis and eosinophilic small granules that were consistent with granular cell tumors. Immunohistochemical studies showed positive staining for S-100 protein. We experienced a case of a granular cell tumor occurring in the suprasternal space and report the importance of including it in the differential diagnosis of subcutaneous soft tissue tumors.

Background: Free flap failure often results from venous thrombosis. The authors developed a rabbit flap model of partial venous obstruction and evaluated four monitoring devices in detecting partial and full venous compromise. Methods: Nine skin flaps were elevated on their arteriovenous pedicles in rabbits. The flap was assessed with quantitative Doppler of arterial inflow, transcutaneous oxygen and carbon dioxide tension, near-infrared spectroscopy tissue oxygen saturation, and scanning laser Doppler imaging. After a stable baseline was achieved, the outflow vein was subjected to partial and full venous obstruction followed by release. Results: Pedicle arterial flow decreased significantly from baseline (5.9 ± 3.0 ml/minute) during partial (4.1 ± 2.4 ml/minute; 30.5 percent; p < 0.01) and full obstruction (0.3 ± 0.4 ml/minute; 94.9 percent; p < 0.01). All other measures changed significantly with full obstruction: transcutaneous oxygen tension decreased by 79.6 percent; transcutaneous carbon dioxide tension increased by 69.0 percent; near-infrared spectroscopy tissue oxygen saturation decreased by 35.7 percent; and scanning laser Doppler imaging decreased by 78.8 percent. Laser Doppler imaging was the only noninvasive device that decreased significantly (p < 0.01) with partial obstruction, from 222.8 ± 77.3 units to 186.5 ± 73.2 units (16.3 percent). Conclusions: The authors established a venous obstruction flap model and evaluated four clinically relevant monitoring devices during partial and full venous occlusion. All devices detected full occlusion, but only scanning laser Doppler imaging and arterial Doppler detected partial occlusion. Scanning laser Doppler imaging monitoring may allow warning of impending venous obstruction. Near-infrared spectroscopy tissue oxygen saturation varied the least between flaps and therefore may be the most easily interpreted device for full venous occlusion. Both characteristics are important for clinical application.

Gas embolism, which occurs with the entry of gas into the circulatory system from the vein, artery or both, is a potentially serious even fatal condition. The two main causes of gas embolism are iatrogenic and diving. The site of entry and the signs and symptoms distinguish between arterial and venous embolism. The entering gas may be air, but may also be CO(2) or other gases, especially in iatrogenic embolism. Supportive care is the primary therapy for venous gas embolism, while hyperbaric oxygen therapy in addition to supportive care is the first line of treatment for arterial gas embolism. In this article, we will review the pathophysiology, etiology, diagnosis and treatment of gas embolism.

Spontaneous celiac artery (CA) dissection is an uncommon cause of acute abdominal pain, accounting for 4% of visceral artery dissections and aneurysms, with the majority of symptomatic visceral artery dissections involving the splenic, hepatic, and superior mesenteric arteries.1,2 Despite a recent increase in the frequency of diagnosis of CA dissection with the use of advanced imaging modalities, its pathogenesis and natural history remain unclear.3 Approximately half of CA dissections are symptomatic, presenting most commonly with acute abdominal pain and unremarkable physical examination and laboratory findings.3,4 A 54-year-old man with a history of hypertension and no recent trauma presented with 6 hours of severe epigastric pain with transient radiation to the back. An initial abdominal computed tomography (CT) angiogram demonstrated a CA aneurysm with an intimal flap extending from the distal celiac artery to the trifurcation (Panels A and B) and a thrombus nearly occluding the splenic artery (Panel C). Hemorrhage was noted in the left anterior pararenal space, and multiple splenic infarctions were present. Repeat imaging 14 hours after presentation showed CA dissection with 90% stenosis at the origin of the common hepatic and

WOS: 000182155100027, PubMed ID: 12735657, …

Abstract 3689 Background: Heparin-induced thrombocytopenia (HIT) is an unpredictable drug reaction to heparin characterized by thrombocytopenia and increased risk of life threatening venous and/or arterial thrombosis. Although HIT is uncommon, it is a serious side effect in patients receiving heparin. Data are lacking if there are additional risk factors that may be associated with the development of HIT. Accordingly, the aim of this study was to identify the risk factors that may be associated with the development of HIT in medical inpatients receiving heparin. Methods: This is a retrospective cohort study with 25,653 patients who were admitted to the medicine service and received heparin products (unfractionated heparin [UFH] or enoxaparin) in an urban teaching hospital in New York City from August 2005 to January 2010. Computerized discharge summaries, medical charts, radiology and laboratory reports were used in this retrospective study. Demographics such as age, gender and race were recorded. Details of medical history and hospital course of each patient was reviewed to obtain the known risk factors for HIT as well as possible confounding factors that may be related to the development of HIT. The diagnosis of HIT was confirmed if the platelet count dropped >50% from baseline and there was a positive laboratory HIT assay. Results: Fifty-five cases of in-hospital HIT (raw incidence, 0.21%, 95% CI [0.16, 0.28]) were observed (Table 1). After multivariate analysis, patients whose race was either Asian or Hispanic demonstrated an increased risk of developing HIT (relative risk [RR]= 2.61; 95% CI [1.10, 6.17]; p= 0.03 and RR= 2.21; 95% CI [1.22, 4.02]; p= 0.01 respectively). Additionally, patients who received full anticoagulation dose with UFH (RR= 3.66; 95% CI [1.98, 6.75]; p= Conclusion: Among patients admitted to inpatient medicine service receiving heparin products, patients who were Asian or Hispanic, who were treated with full anticoagulation dose with UFH or who received heparin product >5 days were at increased risk of HIT. Furthermore, patients who were on hemodialysis, had autoimmune disease, gout and heart failure were also at increased risk of in-hospital HIT. The results suggest that when using heparin products in these patient cohorts, increased surveillance of HIT is necessary. Disclosures: No relevant conflicts of interest to declare.