Does resuscitation with plasma increase the risk of venous thromboembolism?

Perioperative Plasma in Addition to Red Blood Cell Transfusions Is Associated With Increased Venous Thromboembolism Risk Postoperatively

BACKGROUND

Perioperative red blood cell (RBC) transfusions increase venous thromboembolic (VTE) events. Although a previous study found that plasma resuscitation after trauma was associated with increased VTE, the risk associated with additional perioperative plasma is unknown.

METHODS

A US claims and EHR database (TriNetX Diamond Network) was queried. We compared surgical patients who received perioperative plasma and RBC to patients who received perioperative RBC but not plasma. Subanalyses included (1) all surgeries (n = 48,580) and (2) cardiovascular surgeries (n = 38,918). Propensity score matching was performed for age at surgery, ethnicity, race, sex, overweight and obesity, type 2 diabetes, disorders of lipoprotein metabolism, essential hypertension, neoplasms, nicotine dependence, coagulopathies, sepsis, chronic kidney disease, liver disease, nonsteroidal anti-inflammatory analgesics, platelet aggregation inhibitors, anticoagulants, hemoglobin level, outpatient service utilization, and inpatient services; surgery type was included for "all surgeries" analyses. Outcomes included 30-day mortality, postoperative VTE, pulmonary embolism (PE), and disseminated intravascular coagulation (DIC).

RESULTS

After matching the surgical cohorts, compared to only RBC, plasma + RBC was associated with higher risk of postoperative mortality (4.52% vs 3.32%, risk ratio [RR]: 1.36 [95% confidence interval, 1.24-1.49]), VTE (3.92% vs 2.70%, RR: 1.36 [1.24-1.49]), PE (1.94% vs 1.33%, RR: 1.46 [1.26-1.68]), and DIC (0.96% vs 0.35%, RR: 2.75 [2.15-3.53]). Among perioperative cardiovascular patients, adding plasma to RBC transfusion was associated with similar increased risk.

CONCLUSIONS

When compared with perioperative RBC transfusion, adding plasma was associated with increased 30-day postoperative mortality, VTE, PE, and DIC risk among surgical and cardiovascular surgical patients. Reducing unnecessary plasma transfusion should be a focus of patient blood management to improve overall value in health care.

Plasma for prevention and treatment of glycocalyx degradation in trauma and sepsis

The endothelial glycocalyx, a gel-like layer that lines the luminal surface of blood vessels, is composed of proteoglycans, glycoproteins, and glycosaminoglycans. The endothelial glycocalyx plays an essential role in vascular homeostasis, and its degradation in trauma and sepsis can lead to microvascular dysfunction and organ injury. While there are no proven therapies for preventing or treating endothelial glycocalyx degradation, some initial literature suggests that plasma may have a therapeutic role in trauma and sepsis patients. Overall, the literature suggesting the use of plasma as a therapy for endothelial glycocalyx degradation is non-clinical basic science or exploratory. Plasma is an established therapy in the resuscitation of patients with hemorrhage for restoration of coagulation factors. However, plasma also contains other bioactive components, including sphingosine-1 phosphate, antithrombin, and adiponectin, which may protect and restore the endothelial glycocalyx, thereby helping to maintain or restore vascular homeostasis. This narrative review begins by describing the endothelial glycocalyx in health and disease: we discuss the overlapping disease mechanisms in trauma and sepsis that lead to its damage and introduce plasma transfusion as a potential therapy for prevention and treatment of endothelial glycocalyx degradation. Second, we review the literature on plasma as an exploratory therapy for endothelial glycocalyx degradation in trauma and sepsis. Third, we discuss the safety of plasma transfusion by reviewing the adverse events associated with plasma and other blood product transfusions, and we examine modern transfusion precautions that have enhanced the safety of plasma transfusion. We conclude that the literature proposes that plasma may have the potential to prevent and treat endothelial glycocalyx degradation in trauma and sepsis, indicating the need for further research.

Spontaneous uterine rupture complicated by bilateral pulmonary emboli: A case report

Spontaneous uterine rupture in unscarred uteri complicated by pulmonary emboli is a rare event with major maternal morbidity and mortality. This is a case of a 32-year-old woman, G1P0, at term, with no pertinent past medical/surgical history, who underwent an emergency cesarean delivery for failed induction of labor complicated by uterine rupture. Post-operatively, the patient was tachycardic and hypoxic. CT arteriogram revealed massive bilateral pulmonary emboli, and she was transferred for specialist care. An emergency pulmonary embolectomy and implantation of an extracorporeal right ventricular assist device were performed. Once the patient was clinically stable, an evaluation for thrombophilias and collagen disorders was done, and was positive for a variant of unknown significance in the ELN gene (c.205G > C). This case report highlights a potential connection between uterine ruptures, hemorrhage, and multiple, large pulmonary emboli. The authors propose a multidisciplinary discussion and evaluation to identify risk factors and biologic causes for these rare but life-threatening complications.

Incidence of factor XII deficiency in critically ill patients with a prolonged activated partial thromboplastin time: a prospective observational study

Limited data is available on factor XII deficiency in critically ill patients with prolonged activated partial thromboplastin time (aPTT). The association of factor XII deficiency with an increased risk of thromboembolism is unclear. This prospective observational study assessed the incidence of factor XII deficiency among critically ill patients with prolonged aPTT (>40 s), whether factor XII deficiency manifesting as prolonged aPTT was associated with an increased risk of thromboembolism, and clotting time on a viscoelastic (ROTEM) test was useful to predict factor XII deficiency. Of the 40 included patients, 48% [95% confidence interval (CI) 33-63) had a factor XII deficiency (mean ± standard deviation of factor XII level of all patients: 54% ± 29%). Factor XII levels were not significantly correlated with the measured aPTT ( r  = -0.163, P  = 0.315). Factor XII deficiency was significantly more common in patients who were less critically ill ( P  = 0.027), but it was not significantly related to Disseminated Intravascular Coagulation scores ( P  = 0.567). The incidence of symptomatic venous thromboembolism ( P  = 0.246), allogeneic blood transfusion ( P  = 0.816), and hospital mortality ( P  = 0.201) were not significantly different between those with and without factor XII deficiency. The clotting time on the viscoelastic test was not predictive of factor XII deficiency (area under the receiver-operating characteristic = 0.605, P  = 0.264). Factor XII deficiency was common in critically ill patients with a prolonged aPTT. There was no association between factor XII deficiency and risk of thromboembolism. The clotting time on ROTEM was not predictive of the presence of factor XII deficiency.

The interaction effect of transfusion history and previous stroke history on the risk of venous thromboembolism in stroke patients: a prospective cohort study

BACKGROUND

Blood transfusion and previous stroke history are two independent risk factors of venous thromboembolism (VTE) in stroke patients. Whether the potential interaction of transfusion history and previous stroke history is associated with a greater risk of VTE remains unclear. This study aims to explore whether the combination of transfusion history and previous stroke history increases the risk of VTE among Chinese stroke patients.

METHODS

A total of 1525 participants from the prospective Stroke Cohort of Henan Province were enrolled in our study. Multivariate logistic regression models were used to explore the associations among transfusion history, previous stroke history and VTE. The interaction was evaluated on both multiplicative and additive scales. The odds ratio (95% CI), relative excess risk of interaction (RERI), attributable proportion (AP), and synergy index (S) of interaction terms were used to examine multiplicative and additive interactions. Finally, we divided our population into two subgroups by National Institutes of Health Stroke Scale (NIHSS) score and re-evaluated the interaction effect in both scales.

RESULTS

A total of 281 (18.4%) participants of 1525 complicated with VTE. Transfusion and previous stroke history were associated with an increased risk of VTE in our cohort. In the multiplicative scale, the combination of transfusion and previous stroke history was statistically significant on VTE in both unadjusted and adjusted models (P<0.05). For the additive scale, the RERI shrank to 7.016 (95% CI: 1.489 ~ 18.165), with the AP of 0.650 (95% CI: 0.204 ~ 0.797) and the S of 3.529 (95% CI: 1.415 ~ 8.579) after adjusting for covariates, indicating a supra-additive effect. In subgroups, the interaction effect between transfusion history and previous stroke history was pronouncedly associated with the increased risk of VTE in patients with NIHSS score > 5 points (P<0.05).

CONCLUSIONS

Our results suggest that there may be a potential synergistic interaction between transfusion history and previous stroke history on the risk of VTE. Besides, the percentage of VTE incidence explained by interaction increased with the severity of stroke. Our findings will provide valuable evidence for thromboprophylaxis in Chinese stroke patients.

Safety of Vitamin K in mechanical heart valve patients with supratherapeutic INR: A systematic review and meta-analysis

BACKGROUND

Patients who had mechanical heart valves and an international normalized ratio (INR) of >5.0 should be managed by temporary cessation of vitamin K antagonist. This study aimed to investigate the safety of low-dose vitamin K1 in patients with mechanical heart valves who have supratherapeutic INR.

METHODS

CINAHL, Cochran Library, Clinical trial.gov, OpenGrey, PubMed, ScienceDirect, and Scopus were systematically searched from the inception up to October 2021 without language restriction. Studies comparing the safety of low-dose vitamin K1 treatment in patients with placebo or other anticoagulant reversal agents were included. We used a random-effect model for the meta-analysis. Publication bias was determined by a funnel plot with subsequent Begg's test and Egger's test.

RESULTS

From 7529 retrieved studies, 3 randomized control trials were included in the meta-analysis. Pooled data demonstrated that low-dose vitamin K was not associated with thromboembolism rate (risk ratio [RR] = 0.94; 95% CI: 0.19-4.55) major bleeding rate (RR = 0.58; 95% CI: 0.07-4.82), and minor bleeding rate (RR = 0.60; 95% CI: 0.07-5.09). Subgroup and sensitivity analysis demonstrated the nonsignificant effect of low-dose vitamin K on the risk of thromboembolism. Publication bias was not apparent, according to Begg's test and Egger's test (P = .090 and 0.134, respectively).

CONCLUSION

The current evidence does not support the role of low-dose vitamin K as a trigger of thromboembolism in supratherapeutic INR patients with mechanical heart valves. Nevertheless, more well-designed studies with larger sample sizes are required to justify this research question.

Characteristics of Deep Venous Thrombosis in Isolated Lower Extremity Fractures and Unsolved Problems in Guidelines: A Review of Recent Literature

Deep venous thrombosis (DVT) has been characterized by a disorder of venous return caused by abnormal blood clotting in deep veins. It often occurs in the lower limbs and is a common complication in orthopaedics. Therefore, relevant professional organizations domestic and overseas had formulated and constantly updated relevant guidelines to prevent the occurrence of DVT. According to the management strategy of the guidelines, the incidence of DVT can be significantly reduced. However, due to the variety of fractures types, the guidelines cannot expound precautions and characteristics of DVT for all fracture types at present, and there are other related unresolved problems. For example, there is still a lack of consistent optimal strategies for the management of DVT following isolated lower extremity fractures with a higher incidence. The best anticoagulant strategies for patients with upper limb fractures, pediatric fractures, and those combined with other injuries are rarely described in orthopaedic guidelines, but such fractures are common in clinical orthopaedics. The long‐term complications after DVT, such as post‐thrombotic syndrome, are not well‐understood. In the absence of clear guidance, orthopaedic surgeons often resort to empiric anticoagulation or conservative treatment, so the prevention effects of DVT are inconsistent. The purpose of this review is to summarize the characteristics of DVT events after isolated lower extremity fractures and to discuss the unsolved issues in the guidelines by reviewing the previous literature and tracing the history of DVT discovery, to provide more scientific and comprehensive recommendations for the prediction and prevention of DVT.

The incidence of venous thromboembolism in children following colorectal resection for inflammatory bowel disease: A multi-center study

BACKGROUND/PURPOSE

Children with inflammatory bowel disease (IBD) have increased risk for venous thromboembolism (VTE). We sought to determine incidence and risk factors for postoperative VTE in a multicenter cohort of pediatric patients undergoing colorectal resection for IBD.

METHODS

Retrospective review of children ≤18 years who underwent colorectal resection for IBD from 2010 to 2016 was performed at four children's hospitals. Primary outcome was VTE that occurred between surgery and last follow-up. Factors associated with VTE were determined using univariable and multivariable analyses.

RESULTS

Two hundred seventy-six patients were included with median age 15 years [13,17]. Forty-two children (15%) received perioperative VTE chemoprophylaxis, and 88 (32%) received mechanical prophylaxis. DVT occurred in 12 patients (4.3%) at a median of 14 days postoperatively [8,147]. Most were portomesenteric (n = 9, 75%) with the remaining catheter-associated DVTs in extremities (n = 3, 25%). There was no association with chemoprophylaxis (p > 0.99). On Cox regression, emergent procedure [HR 18.8, 95%CI: 3.18-111], perioperative plasma transfusion [HR 25.1, 95%CI: 2.4-259], and postoperative infectious complication [HR 10.5, 95%CI: 2.63-41.8] remained predictive of DVT.

CONCLUSION

Less than 5% of pediatric IBD patients developed postoperative VTE. Chemoprophylaxis was not protective but rarely used. Patients with risk factors identified in this study should be monitored or given prophylaxis for VTE.

LEVEL OF EVIDENCE

Treatment Study, Level III.

Safety and efficacy of prothrombin complex concentrate (PCC) for anticoagulation reversal in patients undergoing urgent neurosurgical procedures: a systematic review and metaanalysis

Anticoagulant therapy poses a significant risk for patients undergoing emergency neurosurgery procedures, necessitating reversal with prothrombin complex concentrate (PCC) or fresh frozen plasma (FFP). Data on PCC efficacy lack consistency in this setting. This systematic review and metaanalysis aimed to evaluate efficacy and safety of PCC for anticoagulation reversal in the context of urgent neurosurgery. Articles from PubMed, Embase, and Cochrane databases were screened according to the PRISMA checklist. Adult patients receiving anticoagulation reversal with PCC for emergency neurosurgical procedures were included. When available, patients who received FFP were included as a comparison group. Pooled estimates of observational studies were calculated for efficacy and safety outcomes via random-effects modeling. Initial search returned 4505 articles, of which 15 studies met the inclusion criteria. Anticoagulants used included warfarin (83%), rivaroxaban (6.8%), phenprocoumon (6.1%), apixaban (2.2%), and dabigatran (1.5%). The mean International Normalized Ratio (INR) prePCC administration ranged from 2.3 to 11.7, while postPCC administration from 1.1 to 1.4. All-cause mortality at 30 days was 27% (95%CI 21, 34%; I² = 44.6%; p-heterogeneity = 0.03) and incidence of thromboembolic events was 6.00% among patients treated with PCC (95%CI 4.00, 10.0%; I² = 0%; p-heterogeneity = 0.83). Results comparing PCC and FFP demonstrated no statistically significant differences in INR reversal, mortality, or incidence of thromboembolic events. This metaanalysis demonstrated adequate safety and efficacy for PCC in the reversal of anticoagulation for urgent neurosurgical procedures. There was no significant difference between PCC and FFP, though further trials would be useful in demonstrating the safety and efficacy of PCC in this setting.

The impact of blood product ratio and procoagulant therapy on the development of thromboembolic events in severely injured hemorrhaging trauma patients

INTRODUCTION

Transfusion therapy in hemorrhaging trauma patients is associated with the development of thromboembolic events. It is unknown whether current resuscitation strategies, including large volumes of plasma and early administration of procoagulant therapy, increases this risk.

METHODS

A systematic search was conducted in MEDLINE, PubMed, and Embase. Studies were screened by two independent reviewers and included if they reported on thromboembolic events in patients with severe trauma (injury severity score ≥16) who received transfusion of at least 1 unit of red blood cells. The ratio by which blood products were transfused, as well as use of procoagulant or antifibrinolytic medication, was recorded.

RESULTS

A total of 40 studies with 11.074 bleeding trauma patients were included, in which 1.145 thromboembolic events were reported, yielding an incidence of 10% thromboembolic events. In studies performing routine screening for thromboembolic complications, the incidence ranged from 12% to 23%. The risk of thromboembolic events was increased after administration of tranexamic acid (TXA; odds ratio [OR], 2.6; 95% confidence interval [CI], 1.7-4.1; p < 0.001) and fibrinogen concentrate (OR, 2.1; 95% CI, 1.0-4.2; p = 0.04). Blood product ratio, the use of prothrombin complex concentrate or recombinant factor VIIa were not associated with thromboembolic events.

CONCLUSION

This systematic review identified an incidence of thromboembolic events of 10% in severely injured bleeding trauma patients. The use of TXA and fibrinogen concentrate was associated with the development of thromboembolic complications.

Venous Thromboembolism in Geriatric Trauma Patients-Risk Factors and Associated Outcomes

BACKGROUND

Venous thromboembolism (VTE) places elderly trauma patients at a high risk of morbidity. The purpose of this study was to determine the outcomes related to VTE in geriatric trauma patients, as well as to identify risk factors for the development of VTE in this population. We also assessed the impact of the type and timing of VTE prophylaxis, and the type of injuries, on development of VTE in geriatric trauma population.

METHODS

We performed a 2-year retrospective review from American College of Surgeons-Trauma Quality Improvement Project (ACS-TQIP) databank from 2014 to 2016. A total of 354,272 patients aged 65 y or older who developed VTE after trauma were included in the study.

RESULTS

Overall, 354,272 elderly trauma patients with complete records were identified from the year 2014 to 2016, and of this, 4290 (1.1%) patients developed in-hospital VTE. Male gender was more predominant in the VTE group (P < 0.001). Both the ICU length of stay and hospital length of stay (P < 0.001) were higher in the VTE group. Spine injury (P = 0.002), lower extremity injury (P < 0.001), age category 75-84 y (P < 0.001), age ≥85 y (P < 0.001), frailty (P < 0.001), severe traumatic brain injury (TBI) (GCS3-8) (P < 0.001), ventilator days (P < 0.001), and transfusion of plasma products in first 24 h of admission (P < 0.001) were independent predictors of developing VTE after trauma in the elderly. Higher injury severity score, TBI, and transfusion of packed red blood cells within 24 h were associated with longer time to initiate VTE prophylaxis. Time to initiate chemical deep vein thrombosis prophylaxis was significantly longer in those patients that developed VTE (3.73 ± 4.82 d), when compared with those patients without VTE ((1.81 ± 2.53 d) (P < 0.001).

CONCLUSIONS

Our study demonstrates that ICU and hospital length of stay were higher in VTE group. Frailty, severe TBI, spine injury, lower extremity injury, longer duration of mechanical ventilation, and transfusion of plasma products in the first 24 h of hospital admission were independent predictors of developing VTE after trauma in elderly. Type and timing of VTE prophylaxis were not significant independent predictors of developing VTE after trauma, while higher injury severity score, TBI, and transfusion of packed red blood cells within 24 h were associated with longer time to initiate VTE prophylaxis. Future multi-institutional prospective studies are warranted to gather more evidence on this topic.

Prevention of Deep Venous Thromboembolism

The nature of many combat wounds puts patients at a high risk of developing deep venous thrombosis (DVT) and pulmonary embolism (PE), which fall under the broader disease category of venous thromboembolism (VTE). In addition to the hypercoagulable state induced by trauma, massive injuries to the extremities, prolonged immobility, and long fixed wing transport times to higher echelons of care are unique risk factors for venous thromboembolism in the combat-injured patient. These risk factors mandate aggressive prophylaxis for DVT and PE that can effectively be achieved by the use of lower extremity sequential compression devices and low dose unfractionated heparin or low molecular weight heparin. In addition, inferior vena cava filters are often used for PE prophylaxis when chemical DVT prophylaxis fails or is contraindicated. The following Department of Defense (DoD) Joint Trauma System (JTS) Clinical Practice Guideline (CPG) discusses the current recommendations for the prevention of DVT and PE including the use of inferior vena cava filters (IVCFs).

Risk factors for venous thromboembolic events in pediatric surgical patients: Defining indications for prophylaxis

BACKGROUND

Venous thromboembolism (VTE) in pediatric surgical patients is a rare event. The risk factors for VTE in pediatric general surgery patients undergoing abdominopelvic procedures are unknown.

STUDY DESIGN

The American College of Surgeon's National Surgical Quality Improvement Program-Pediatric (NSQIP-P) database (2012-2015) was queried for patients with VTE after abdominopelvic general surgery procedures. Patient and operative variables were assessed to identify risk factors associated with VTE and develop a pediatric risk score.

RESULTS

From 2012-2015, 68 of 34,813 (0.20%) patients who underwent abdominopelvic general surgery procedures were diagnosed with VTE. On multivariate analysis, there was no increased risk of VTE based on concomitant malignancy, chemotherapy, inflammatory bowel disease, or laparoscopic surgical approach, while a higher rate of VTE was identified among female patients. The odds of experiencing VTE were increased on stepwise regression for patients older than 15 years and those with preexisting renal failure or a diagnosis of septic shock, patients with American Society of Anesthesia (ASA) classification ≥ 2, and for anesthesia time longer than 2 h. The combination of age > 15 years, ASA classification ≥ 2, anesthesia time > 2 h, renal failure, and septic shock was included in a model for predicting risk of VTE (AUC = 0.907, sensitivity 84.4%, specificity 88.2%).

CONCLUSION

VTE is rare in pediatric patients, but prediction modeling may help identify those patients at heightened risk. Additional studies are needed to validate the factors identified in this study in a risk assessment model as well as to assess the efficacy and cost-effectiveness of prophylaxis methods.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Factor VIIa administration in orthotopic heart transplant recipients and its impact on thromboembolic events and post-transplant outcomes

Recombinant, activated factor VIIa (rFVIIa) is used during cardiac surgeries to mitigate refractory coagulopathic bleeding. The purpose of this study was to examine whether rFVIIa use in orthotopic heart transplant (OHT) recipients was associated with a higher incidence of thromboembolic (TE) events compared to patients who did not. A single-center, retrospective, cohort study was performed on OHT recipients who received rFVIIa for refractory coagulopathic bleeding from January 2013 to December 2015. Patients were evaluated for up to 6 months after transplantation and assessed for TE events, rejection, readmissions, graft survival, and patient survival. Categorical variables were analyzed using the Chi square test while student's t or ANOVA testing was utilized for continuous variables. Of the 62 patients who met inclusion criteria, 27 patients received rFVIIa, and 35 patients were selected for the control group. The overall incidence of TE events was not significantly different between patients who received rFVIIa compared to patients in the control group (14.8% vs 11.4%) (p = 0.69). Within 14 days, 14.81% of rFVIIa patients suffered a TE event compared to 5.7% of the control group (p = 0.23). Rejection, readmissions, graft survival, and patient survival were not significantly different at any time points. Use of rFVIIa in heart transplantation showed no difference in the overall rate of TE events, however, there was a nonsignificant trend toward higher risk of early TE development in the rFVIIa group compared to the control group.

Risk factors for deep vein thrombosis and pulmonary embolism after traumatic injury: A competing risks analysis

BACKGROUND

Venous thromboembolism, including deep vein thrombosis (DVT) and pulmonary embolism (PE), is typically reported as a composite measure of the quality of trauma center care. Given that recent data suggesting postinjury DVT and PE are distinct clinical processes, a better understanding may result from analyzing them as independent, competing events. Using competing risks analysis, we evaluated our hypothesis that the risk factors and timing of postinjury DVT and PE are different.

METHODS

We examined all adult trauma patients admitted to our Level I trauma center from July 2006 to December 2011 who received at least one surveillance duplex ultrasound of the lower extremities and who were at high risk or greater for DVT. Outcomes included DVT and PE events, and time-to-event from admission. We used competing risks analysis to evaluate risk factors for DVT while accounting for PE as a competing event, and vice versa.

RESULTS

Of 2,370 patients, 265 (11.2%) had at least one venous thromboembolism event, 235 DVT only, 19 PE only, 11 DVT and PE. Within 2 days of admission, 38% of DVT cases had occurred compared with 26% of PE. Competing risks modeling of DVT as primary event identified older age, severe injury (Injury Severity Score, ≥ 15), mechanical ventilation longer than 4 days, active cancer, history of DVT or PE, major venous repair, male sex, and prophylactic enoxaparin and prophylactic heparin as associated risk factors. Modeling of PE as the primary event showed younger age, nonsevere injury (Injury Severity Score, < 15), central line placement, and prophylactic heparin as relevant factors.

CONCLUSION

The risk factors for PE and DVT after injury were different, suggesting that they are clinically distinct events that merit independent consideration. Many DVT events occurred early despite prophylaxis, bringing into question the preventability of postinjury DVT. We recommend trauma center quality reporting program measures be revised to account for DVT and PE as unique events.

LEVEL OF EVIDENCE

Epidemiologic, level III.

Should Prophylactic Anticoagulation Be Considered with Large Uterine Leiomyoma? A Case Series and Literature Review

Introduction. Uterine leiomyomas, also called uterine fibroids or myomas, are the most common pelvic tumors in women. They are very rarely the cause of acute complications. However, when complications occur they cause significant morbidity and mortality. Thromboembolic disease has been described as a rare complication of uterine leiomyomas. DVT is a serious illness, sometimes causing death due to acute PE. Cases. We report a case series of 3 patients with thromboembolic disease associated with uterine leiomyoma at Hurley Medical Center, Flint, Michigan, during 2015 and conduct a literature review on the topic. A literature search was conducted using Medline, PubMed, and PMC databases from 1966 to 2015. Conclusion. The uterine leiomyoma is a very rare cause of PE and only few cases have been reported. DVT secondary to uterine leiomyoma should be considered in a female presenting with abdominal mass and pelvic pressure, if there is no clear common cause for her symptoms. Thromboembolic disease secondary to large uterine leiomyoma should be treated with acute stabilization and then hysterectomy. Prophylactic anticoagulation would be beneficial for lowering the risk of VTE in patients with large uterine leiomyoma.

Tactical damage control resuscitation in austere military environments

BACKGROUND

Despite the early uses of tourniquets and haemostatic dressings, blood loss still accounts for the vast majority of preventable deaths on the battlefield. Over the last few years, progress has been made in the management of such injuries, especially with the use of damage control resuscitation concepts. The early application of these procedures, on the field, may constitute the best opportunity to improve survival from combat injury during remote operations.

DATA SOURCES

Currently available literature relating to trauma-induced coagulopathy treatment and far-forward transfusion was identified by searches of electronic databases. The level of evidence and methodology of the research were reviewed for each article. The appropriateness for field utilisation of each medication was then discussed to take into account the characteristics of remote military operations.

CONCLUSIONS

In tactical situations, in association with haemostatic procedures (tourniquet, suture, etc), tranexamic acid should be the first medication used according to the current guidelines. The use of fibrinogen concentrate should also be considered for patients in haemorrhagic shock, especially if point-of-care (POC) testing of haemostasis or shock severity is available. If POC evaluation is not available, it seems reasonable to still administer this treatment after clinical assessment, particularly if the evacuation is delayed. In this situation, lyophilised plasma may also be given as a resuscitation fluid while respecting permissive hypotension. Whole blood transfusion in the field deserves special attention. In addition to the aforementioned treatments, if the field care is prolonged, whole blood transfusion must be considered if it does not delay the evacuation.

Platelet-derived microparticles trigger THP-1 monocytic cell aggregation and release of pro-coagulant tissue factor-expressing microparticles in vitro

Microparticles (MPs) released by blood or endothelial cells are present in plasma for transfusion. They originate from the collected donor blood or are triggered by the variable steps taking place during collection and production/storage processes of blood components. While MPs may contribute to hemostasis, their presence in transfused plasma may lead to uncontrolled thrombin generation when transfused to susceptible cancer or hypercoagulable patients. Understanding the biochemical and cellular triggers of MP-mediated thrombogenesis is therefore crucial. We isolated platelet MPs (PMPs) present in platelet concentrate supernatant plasma (N-PMPs) or prepared by activation of isolated platelets using 0.1 IU/mL thrombin (T-PMPs). N-PMPs and T-PMPs were characterized by dynamic light scattering and counted by tunable resistive pulse sensing to determine population size and number. T-MPMs, but not N-PMPs, induced immediate, long-lasting, strong aggregation of THP-1 monocytic cells in vitro. In addition, co-cultures of THP-1 cells with both N-PMPs and T-PMPs triggered the generation of pro-coagulant tissue factor (TF)-bearing MPs from THP-1 cells. Therefore, some PMPs may induce THP-1 monocytic cell aggregation in vitro and trigger immune cell-mediated thrombogenicity linked to the release of pro-coagulant tissue factor-bearing MPs. Controlling the impact of the presence of PMPs in transfused blood components in certain patient population or critically ill patients deserves in-depth consideration.