Prevention of Venous Thromboembolism in the ICU

Incidence and Risk Factors for Deep Venous Thrombosis and Its Impact on Outcome in Patients Admitted to Medical Critical Care

Objectives

This study evaluated the incidence and risk factors for deep venous thrombosis (DVT) while on thromboprophylaxis, in patients admitted to the medical intensive care unit (MICU), and to assess its impact on outcomes.

Methods

Consecutive patients admitted to the MICU underwent compression ultrasound of the jugular, axillary, femoral, and popliteal veins at admission, day 3 and 7 to screen for DVT. All patients were on pharmacological and/or mechanical thromboprophylaxis as per protocol. The primary outcome was the incidence of DVT (defined as occurrence on day 3 or 7). Secondary outcomes were death and duration of hospitalization. Risk factors for DVT were explored using bivariate and multivariable logistic regression analysis and expressed as risk ratio (RR) with 95% confidence intervals (CIs).

Results

The incidence of DVT was 17.2% (95% CI 12.0, 22.3) (n = 35/203); two-thirds were catheter associated (23/35). There was no difference in mortality between those with and without incident DVT (9/35 vs 40/168, p = 0.81). The mean (SD) duration of hospitalization was longer in the DVT group (20.1 (17) vs 12.9 (8.5) days, p = 0.007). Although day 3 INR (RR 2.1, 95% CI 0.9-5.3), age >40 years (2.1, 0.8-5.3), vasopressor use (1.0, 0.4-2.9) and SOFA score (0.9, 0.85-1.1) were associated with the development of DVT on bivariate analysis, only central venous catheters (15.97, 1.9-135.8) was independently associated with DVT on multivariable analysis.

Conclusions

Despite thromboprophylaxis, 17% of ICU patients develop DVT. The central venous catheter is the main risk factor. DVT is not associated with increased mortality in the setting of prophylaxis.

How to cite this article

Krishnamoorthy A, Hansdak SG, Peter JV, Pichamuthu K, Rajan SJ, Sudarsan TI, et al. Incidence and Risk Factors for Deep Venous Thrombosis and Its Impact on Outcome in Patients Admitted to Medical Critical Care. Indian J Crit Care Med 2024;28(6):607-613.

Enhanced renal clearance impacts levetiracetam concentrations in patients with traumatic brain injury with and without augmented renal clearance

BACKGROUND

The purpose of this study was to examine the impact of ARC on levetiracetam concentrations during the first week following acute TBI. The hypothesis was levetiracetam concentrations are significantly lower in TBI patients with augmented renal clearance (ARC) compared to those with normal renal clearance.

METHODS

This is a prospective cohort pharmacokinetic study of adults with moderate to severe TBI treated with levetiracetam during the first week after injury. Serial blood collections were performed daily for analysis of levetiracetam, cystatin C, and 12-hr creatinine clearance (CrCl) determinations. Patients were divided into two cohorts: with (CrCl ≥130 ml/min/1.73 m2) and without ARC.

RESULTS

Twenty-two patients with moderate to severe TBI were included. The population consisted primarily of young male patients with severe TBI (mean age 40 years old, 68% male, median admission GCS 4). Each received levetiracetam 1000 mg IV every 12 h for the study period. ARC was present in 77.3% of patients, with significantly lower levetiracetam concentrations in ARC patients and below the conservative therapeutic range (< 6mcg/mL) for all study days. In patients without ARC, the serum concentrations were also below the expected range on all but two study days (Days 4 and 5). Four of the 22 (18.2%) patients exhibited seizure activity during the study period (two of these patients exhibited ARC). Cystatin C concentrations were significantly lower in patients with ARC, though the mean for all patients was within the typical normal range.

CONCLUSIONS

ARC has a high prevalence in patients with moderate to severe TBI. Levetiracetam concentrations after standard dosing were low in all TBI patients, but significantly lower in patients with ARC. This study highlights the need to consider personalized drug dosing in TBI patients irrespective of the presence of ARC.

CLINICAL TRIAL REGISTRATION

This study was registered at cliicaltrials.gov (NCT02437838) Registered on 08/05/2015, https://clinicaltrials.gov/ct2/show/NCT02437838 .

SARS-CoV-2 Positivity in Ambulatory Symptomatic Patients Is Not Associated With Increased Venous or Arterial Thrombotic Events in the Subsequent 30 Days

BACKGROUND

COVID-19 has been associated with increased risk of thromboembolism in critically ill patients.

OBJECTIVE

We sought to examine the association of SARS-CoV-2 test positivity and subsequent acute vascular thrombosis, including venous thromboembolism (VTE) or arterial thrombosis (AT), in a large nationwide registry of emergency department (ED) patients tested with a nucleic acid test for suspected SARS-CoV-2.

METHODS

The RECOVER (Registry of Potential COVID-19 in Emergency Care) registry includes 155 EDs across the United States. We performed a retrospective cohort study to produce odds ratios (ORs) for COVID-19-positive vs. COVID-19-negative status as a predictor of 30-day VTE or AT, adjusting for age, sex, active cancer, intubation, hospital length of stay, and intensive care unit (ICU) care.

RESULTS

Comparing 14,056 COVID-19-positive patients with 12,995 COVID-19-negative patients, the overall 30-day prevalence of VTE events was 1.4% vs. 1.3%, respectively (p = 0.44, χ²). Multivariable analysis identified that testing positive for SARS-CoV-2 status was negatively associated with both VTE (OR 0.76; 95% confidence interval [CI] 0.61-0.94) and AT (OR 0.51; 95% CI 0.32-0.80), whereas intubation, ICU care, and age 50 years or older were positively associated with both VTE and AT.

CONCLUSIONS

In contrast to other reports, results from this large, hetereogenous national sample of ED patients tested for SARS-CoV-2, showed no association between vascular thrombosis and COVID-19 test positivity.

Coagulopathy and Fibrinolytic Pathophysiology in COVID-19 and SARS-CoV-2 Vaccination

Coronavirus Disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and is frequently complicated by thrombosis. In some cases of severe COVID-19, fibrinolysis may be markedly enhanced within a few days, resulting in fatal bleeding. In the treatment of COVID-19, attention should be paid to both coagulation activation and fibrinolytic activation. Various thromboses are known to occur after vaccination with SARS-CoV-2 vaccines. Vaccine-induced immune thrombotic thrombocytopenia (VITT) can occur after adenovirus-vectored vaccination, and is characterized by the detection of anti-platelet factor 4 antibodies by enzyme-linked immunosorbent assay and thrombosis in unusual locations such as cerebral venous sinuses and visceral veins. Treatment comprises high-dose immunoglobulin, argatroban, and fondaparinux. Some VITT cases show marked decreases in fibrinogen and platelets and marked increases in D-dimer, suggesting the presence of enhanced-fibrinolytic-type disseminated intravascular coagulation with a high risk of bleeding. In the treatment of VITT, evaluation of both coagulation activation and fibrinolytic activation is important, adjusting treatments accordingly to improve outcomes.

Management of acute atrial fibrillation in the intensive care unit: An international survey

BACKGROUND

Atrial fibrillation (AF) is common in intensive care unit (ICU) patients and is associated with poor outcomes. Different management strategies exist, but the evidence is limited and derived from non-ICU patients. This international survey of ICU doctors evaluated the preferred management of acute AF in ICU patients.

METHOD

We conducted an international online survey of ICU doctors with 27 questions about the preferred management of acute AF in the ICU, including antiarrhythmic therapy in hemodynamically stable and unstable patients and use of anticoagulant therapy.

RESULTS

A total of 910 respondents from 70 ICUs in 14 countries participated in the survey with 24%-100% of doctors from sites responding. Most ICUs (80%) did not have a local guideline for the management of acute AF. The preferred first-line strategy for the management of hemodynamically stable patients with acute AF was observation (95% of respondents), rhythm control (3%), or rate control (2%). For hemodynamically unstable patients, the preferred strategy was observation (48%), rhythm control (48%), or rate control (4%). Overall, preferred antiarrhythmic interventions included amiodarone, direct current cardioversion, beta-blockers other than sotalol, and magnesium in that order. A total of 67% preferred using anticoagulant therapy in ICU patients with AF, among whom 61% preferred therapeutic dose anticoagulants and 39% prophylactic dose anticoagulants.

CONCLUSION

This international survey indicated considerable practice variation among ICU doctors in the clinical management of acute AF, including the overall management strategies and the use of antiarrhythmic interventions and anticoagulants.

Development and validation of a prediction model for deep vein thrombosis in older non-mild acute pancreatitis patients

BACKGROUND

Deep vein thrombosis (DVT) may cause pulmonary embolus, leading to late deaths. The systemic inflammatory and hypercoagulable state of moderate and severe acute pancreatitis (non-mild acute pancreatitis, NMAP) patients may contribute to the development of venous thromboembolism. Accurate prediction of DVT is conducive to clinical decisions.

AIM

To develop and validate a potential new prediction nomogram model for the occurrence of DVT in NMAP.

METHODS

NMAP patient admission between 2013.1.1 and 2018.12.31 at the West China Hospital of Sichuan University was collected. A total of 220 patients formed the training set for nomogram development, and a validation set was constructed using bootstrapping with 100 resamplings. Univariate and multivariate logistic regression analyses were used to estimate independent risk factors associated with DVT. The independent risk factors were included in the nomogram. The accuracy and utility of the nomogram were evaluated by calibration curve and decision curve analysis, respectively.

RESULTS

A total of 220 NMAP patients over 60 years old were enrolled for this analysis. DVT was detected in 80 (36.4%) patients. The final nomogram included age, sex, surgery times, D-dimer, neutrophils, any organ failure, blood culture, and classification. This model achieved good concordance indexes of 0.827 (95%CI: 0.769-0.885) and 0.803 (95%CI: 0.743-0.860) in the training and validation sets, respectively.

CONCLUSION

We developed and validated a prediction nomogram model for DVT in older patients with NMAP. This may help guide doctors in making sound decisions regarding the administration of DVT prophylaxis.

Sulfated poly-amido-saccharides (sulPASs) are anticoagulants in vitro and in vivo

Anticoagulant therapeutics are a mainstay of modern surgery and of clotting disorder management such as venous thrombosis, yet performance and supply limitations exist for the most widely used agent - heparin. Herein we report the first synthesis, characterization, and performance of sulfated poly-amido-saccharides (sulPASs) as heparin mimetics. sulPASs inhibit the intrinsic pathway of coagulation, specifically FXa and FXIa, as revealed by ex vivo human plasma clotting assays and serine protease inhibition assays. sulPASs activity positively correlates with molecular weight and degree of sulfation. Importantly, sulPASs are not degraded by heparanases and are non-hemolytic. In addition, their activity is reversed by protamine sulfate, unlike small molecule anticoagulants. In an in vivo murine model, sulPASs extend clotting time in a dose dependent manner with bleeding risk comparable to heparin. These findings support continued development of synthetic anticoagulants to address the clinical risks and shortages associated with heparin.

Venous Thromboembolism Prophylaxis in Critically Ill Adults: A Systematic Review and Network Meta-analysis

BACKGROUND

Critically ill adults are at increased risk of VTE, including DVT, and pulmonary embolism. Various agents exist for venous thromboprophylaxis in this population.

RESEARCH QUESTION

What is the comparative efficacy and safety of prophylaxis agents for prevention of VTE in critically ill adults?

STUDY DESIGN AND METHODS

Systematic review and network meta-analysis of randomized clinical trials (RCTs) evaluating efficacy of thromboprophylaxis agents among critically ill patients. We searched six databases (including PubMed, EMBASE, and Medline) from inception through January 2021 for RCTs of patients in the ICU receiving pharmacologic, mechanical, or combination therapy (pharmacologic agents and mechanical devices) for thromboprophylaxis. Two reviewers performed screening, full-text review, and extraction. We used the Grading of Recommendations Assessment, Development, and Evaluation to rate certainty of effect estimates.

RESULTS

We included 13 RCTs (9,619 patients). Compared with control treatment (a composite of no prophylaxis, placebo, or compression stockings only), low-molecular-weight heparin (LMWH) reduced the incidence of DVT (OR, 0.59 [95% credible interval [CrI], 0.33-0.90]; high certainty) and unfractionated heparin (UFH) may reduce the incidence of DVT (OR, 0.82 [95% CrI, 0.47-1.37]; low certainty). LMWH probably reduces DVT compared with UFH (OR, 0.72 [95% CrI, 0.46-0.98]; moderate certainty). Compressive devices may reduce risk of DVT compared with control treatments; however, this is based on low-certainty evidence (OR, 0.85 [95% CrI, 0.50-1.50]). Combination therapy showed unclear effect on DVT compared with either therapy alone (very low certainty).

INTERPRETATION

Among critically ill adults, compared with control treatment, LMWH reduces incidence of DVT, whereas UFH and mechanical compressive devices may reduce the risk of DVT. LMWH is probably more effective than UFH in reducing incidence of DVT and should be considered the primary pharmacologic agent for thromboprophylaxis. The efficacy and safety of combination pharmacologic therapy and mechanical compressive devices were unclear.

TRIAL REGISTRY

Open Science Framework; URL: https://osf.io/694aj.

COVID-19 Sepsis: Pathogenesis and Endothelial Molecular Mechanisms Based on "Two-Path Unifying Theory" of Hemostasis and Endotheliopathy-Associated Vascular Microthrombotic Disease, and Proposed Therapeutic Approach with Antimicrothrombotic Therapy

COVID-19 sepsis is characterized by acute respiratory distress syndrome (ARDS) as a consequence of pulmonary tropism of the virus and endothelial heterogeneity of the host. ARDS is a phenotype among patients with multiorgan dysfunction syndrome (MODS) due to disseminated vascular microthrombotic disease (VMTD). In response to the viral septicemia, the host activates the complement system which produces terminal complement complex C5b-9 to neutralize pathogen. C5b-9 causes pore formation on the membrane of host endothelial cells (ECs) if CD59 is underexpressed. Also, viral S protein attraction to endothelial ACE2 receptor damages ECs. Both affect ECs and provoke endotheliopathy. Disseminated endotheliopathy activates two molecular pathways: inflammatory and microthrombotic. The former releases inflammatory cytokines from ECs, which lead to inflammation. The latter initiates endothelial exocytosis of unusually large von Willebrand factor (ULVWF) multimers and FVIII from Weibel-Palade bodies. If ADAMTS13 is insufficient, ULVWF multimers activate intravascular hemostasis of ULVWF path. In activated ULVWF path, ULVWF multimers anchored to damaged endothelial cells recruit circulating platelets and trigger microthrombogenesis. This process produces "microthrombi strings" composed of platelet-ULVWF complexes, leading to endotheliopathy-associated VMTD (EA-VMTD). In COVID-19, microthrombosis initially affects the lungs per tropism causing ARDS, but EA-VMTD may orchestrate more complex clinical phenotypes, including thrombotic thrombocytopenic purpura (TTP)-like syndrome, hepatic coagulopathy, MODS and combined micro-macrothrombotic syndrome. In this pandemic, ARDS and pulmonary thromboembolism (PTE) have often coexisted. The analysis based on two hemostatic theories supports ARDS caused by activated ULVWF path is EA-VMTD and PTE caused by activated ULVWF and TF paths is macrothrombosis. The thrombotic disorder of COVID-19 sepsis is consistent with the notion that ARDS is virus-induced disseminated EA-VMTD and PTE is in-hospital vascular injury-related macrothrombosis which is not directly  related to viral pathogenesis. The pathogenesis-based therapeutic approach is discussed for the treatment of EA-VMTD with antimicrothrombotic regimen and the potential need of anticoagulation therapy for coinciding macrothrombosis in comprehensive COVID-19 care.

Prevention, diagnosis, and management of venous thromboembolism in the critically ill surgical and trauma patient

PURPOSE OF REVIEW

Venous thromboembolism (VTE), which encompasses deep vein thrombosis and pulmonary embolism, is common among trauma patients and critically ill surgical patients admitted to the ICU. Critical care surgical patients are at an extremely high risk for VTE and the related morbidity and mortality associated with it. The present review aims to provide an overview of the importance of identifying risk factors, prescribing effective prohylaxis, accurate diagnosis, and timely appropriate treatment for trauma and critically ill surgical patients with VTE in the ICU.

RECENT FINDINGS

VTE is a healthcare burden among critically ill surgical patients that is mostly preventable through adherence to prophylactic protocols that aim to recognize VTE risk factors while simultaneously providing guidance to appropriate timing and administration prophylaxis regimens. Newer pharmacologic therapies for prophylaxis and treatment, diagnostic modalities, and indications for therapy of VTE have continued to evolve.

SUMMARY

Critical care surgical and trauma patients represent a population that are at a heightened risk for VTE and associated complications. Appropriate screening, prevention strategies, accurate diagnosis, and timely administration of appropriate treatment must be utilized to reduce morbidity and mortality.

Prognostic nomogram for 30-day mortality of deep vein thrombosis patients in intensive care unit

Background

We aimed to use the Medical Information Mart for Intensive Care III database to build a nomogram to identify 30-day mortality risk of deep vein thrombosis (DVT) patients in intensive care unit (ICU).

Methods

Stepwise logistic regression and logistic regression with least absolute shrinkage and selection operator (LASSO) were used to fit two prediction models. Bootstrap method was used to perform internal validation.

Results

We obtained baseline data of 535 DVT patients, 91 (17%) of whom died within 30 days. The discriminations of two new models were better than traditional scores. Compared with simplified acute physiology score II (SAPSII), the predictive abilities of two new models were improved (Net reclassification improvement [NRI] > 0; Integrated discrimination improvement [IDI] > 0; P < 0.05). The Brier scores of two new models in training set were 0.091 and 0.108. After internal validation, corrected area under the curves for two models were 0.850 and 0.830, while corrected Brier scores were 0.108 and 0.114. The more concise model was chosen to make the nomogram.

Conclusions

The nomogram developed by logistic regression with LASSO model can provide an accurate prognosis for DVT patients in ICU.

Thromboprophylaxis with enoxaparin is associated with a lower death rate in patients hospitalized with SARS-CoV-2 infection. A cohort study

BACKGROUND

Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS-CoV-2) infection is associated with hypercoagulability caused by direct invasion of endothelial cells and\or proinflammatory cytokine release. Thromboprophylaxis with enoxaparin is recommended by current guidelines, but evidence is still weak. The aim of this study was to assess the impact of thromboprophylaxis with enoxaparin on hospital mortality in patients admitted for Coronavirus disease 2019 (COVID-19). The effects of enoxaparin on intensive care admission and hospital length-of-stay were evaluated as secondary outcomes.

METHODS

Observational cohort study, with data collected from patients admitted to Poliambulanza Foundation with positive real time reverse transcription polymerase chain reaction (RT-PCR) for SARS-CoV-2 from 20th February to 10th May 2020. Multivariate logistic regression with overlap weight propensity score was used to model hospital mortality and intensive care admission, hospital length-of-stay was analyzed with a multivariate Poisson regression. Seven hundred and ninety nine (57%) patients who received enoxaparin at least once during the hospitalization were included in the enoxaparin cohort, 604 (43%) patients who did not were included in the control cohort.

FINDINGS

At the adjusted analysis enoxaparin was associated with lower in-hospital mortality (Odds Ratio 0·53, 95% C.I. 0·40-0·70) compared with no enoxaparin treatment. Hospital length-of-stay was longer for patients treated with enoxaparin (Incidence Rate Ratios 1·45, 95% C.I. 1·36-1·54). Enoxaparin treatment was associated with reduced risk of intensive care admission at the adjusted analysis (Odds Ratio 0·48, 95% C.I. 0·32-0·69).

INTERPRETATION

This study shows that treatment with enoxaparin during hospital stay is associated with a lower death rate and, while results from randomized clinical trials are still pending, this study supports the use of thromboprophylaxis with enoxaparin in all patients admitted for COVID-19. Moreover, when enoxaparin is used on the wards, it reduces the risk of Intensive Care Unit admission.

Emerging patterns of hypercoagulability associated with critical COVID-19: A review

While the COVID-19 pandemic sweeps the world, much evidence is being gathered regarding its novel pathological mechanisms. It is the authors' clinical experience that patients in the intensive care unit suffering from COVID-19 are extremely pro-coagulable, with venous and arterial thromboembolism frequently observed, and losses of vascular access lines and filtration circuits to thrombosis now commonplace. Here, we explore the evidence for hypercoagulability in this group, presenting evidence of both a localised pulmonary hypercoagulability, and a systemic hypercoagulability resulting in thrombosis distant to the pulmonary vasculature. Furthermore, we discuss the possible risk factors exacerbated by, or selected for in COVID-19. We review the available evidence for use of plasma D-dimer as a prognostic marker, exploring the possibility that it acts as a marker of a COVID-19-associated hypercoagulability. We review the evidence for a pro-coagulant subtype of disseminated intravascular coagulation, discussing its clinical significance. Finally, we discuss the current evidence surrounding treatment of COVID-19 hypercoagulability, including prophylactic and treatment-dose heparin, thrombolytic agents, antiplatelet agents, and direct thrombin inhibitors, among others. We suggest areas in which further investigation is urgently needed to reduce the startling incidence of thrombosis in this group, a complication no doubt contributing to morbidity and mortality.

Clinical Update for Physical Therapists: Coagulopathy and COVID-19

Physical therapists have a unique role in both prevention of venous thromboembolism (VTE) through the promotion of early mobility and physical activity and diagnosis through discovery of signs and symptoms of VTE. This Perspective updates clinicians on the latest information regarding pathophysiology of coagulopathy associated with COVID-19 and applies VTE clinical practice guidelines to COVID-19 in order to provide guidance on physical therapist management.

Prophylactic unfractionated heparin and hemorrhage in neurocritically ill underweight patients: A case series and review of the literature

PURPOSE

Three cases of major bleeding associated with thromboprophylactic unfractionated heparin (UFH) therapy in underweight neurocritically ill patients are reported.

SUMMARY

Three underweight patients (body mass index of <18.5 kg/m2) were treated in the intensive care unit with major bleeds associated with UFH thromboprophylaxis. Two of the patients, a 76-year-old female and a 56-year-old female, had hemorrhages on presentation; the third patient, a 29-year-old male, developed bleeding during his admission. All 3 patients had past medical histories consisting of acute neurologic conditions within 6 weeks of presentation, including subdural hematoma, subarachnoid hemorrhage, and obstructive hydrocephalus secondary to a brain mass. All hemorrhages developed following the receipt of prophylactic UFH at doses of 5,000 units every 8 to 12 hours, which translated to high weight-based dosages (>300 units/kg/d). Additionally, hemorrhages were associated with prolonged activated partial thromboplastin time, which declined following heparin discontinuation. The major bleeds following UFH administration included an acute on chronic subdural hematoma, acute rectus sheath hematoma, and cerebellar hematoma. Stabilization of the subdural hematoma was achieved without the use of protamine and the patient was discharged in stable condition. The other 2 patients expired secondary to their hemorrhagic events. Naranjo nomogram scores for the patients indicated that heparin was the probable cause of bleed in 2 cases and a possible cause in 1 case.

CONCLUSION

Three major hemorrhages developed following the administration of UFH. Underweight patients with neurologic injury may require increased clinical vigilance, reduced doses, and pharmacodynamic monitoring to improve safety outcomes associated with thromboprophylaxis.

COVID-19 and Thrombotic or Thromboembolic Disease: Implications for Prevention, Antithrombotic Therapy, and Follow-Up: JACC State-of-the-Art Review

Coronavirus disease-2019 (COVID-19), a viral respiratory illness caused by the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2), may predispose patients to thrombotic disease, both in the venous and arterial circulations, because of excessive inflammation, platelet activation, endothelial dysfunction, and stasis. In addition, many patients receiving antithrombotic therapy for thrombotic disease may develop COVID-19, which can have implications for choice, dosing, and laboratory monitoring of antithrombotic therapy. Moreover, during a time with much focus on COVID-19, it is critical to consider how to optimize the available technology to care for patients without COVID-19 who have thrombotic disease. Herein, the authors review the current understanding of the pathogenesis, epidemiology, management, and outcomes of patients with COVID-19 who develop venous or arterial thrombosis, of those with pre-existing thrombotic disease who develop COVID-19, or those who need prevention or care for their thrombotic disease during the COVID-19 pandemic.

Practice Patterns of Venous Thromboembolism Prophylaxis in Underweight, Critically Ill Patients with Neurologic Injury

PURPOSE

Venous thromboembolism (VTE) prophylaxis in underweight patients with neurologic injury remains unaddressed by guidelines and primary literature. This study aimed to describe VTE prophylaxis strategies employed in this population and compare the impact of underweight and non-obese patients on thrombotic and bleeding events.

METHODS

A retrospective review of adults admitted with a diagnosis of neurologic injury to a neurology/neurosurgery intensive care unit (ICU) over 6 years. Patients admitted ≥72 h with an order for VTE prophylaxis during admission, and a body mass index (BMI) <30 kg/m² were included. Patients were stratified to underweight (BMI ≤18.5 kg/m² or weight ≤50.0 kg) or non-obese (BMI 18.6-29.9 kg/m²) groups and matched, 2:1, on age, diagnosis, and disease severity.

RESULTS

The most common regimen in the underweight (n = 107) and non-obese (n = 214) group was unfractionated heparin (UFH) 5000 units subcutaneously Q12 h (69.1 vs. 83.6%; p = 0.003). Only underweight patients received UFH 2500 units subcutaneously Q12 h (17.8 vs. 0.0%; p < 0.0001). The proportion of overall bleeding and thrombotic events while receiving VTE prophylaxis was not significantly different. The proportion of underweight patients developing intracranial hematoma expansion while receiving prophylaxis versus non-obese patients (45.5 vs. 8.3%; p = 0.017) was significant. Patients receiving >150 units/kg/day of UFH displayed a trend toward increased risk of bleeding (9.7 vs. 4.2%; p = 0.064).

CONCLUSIONS

Current practice does not reflect dose reductions for neurologically injured, underweight patients. Caution should be considered when using increased doses of UFH in neurologically injured patients that are underweight and/or may be exposed to >150 units/kg/day of UFH. Continued assessment of VTE prophylaxis is needed to confirm these findings.

Clinical Experience With Pharmacological Venous Thromboembolism Prophylaxis in the Underweight and Critically Ill

BACKGROUND

The optimal regimen for pharmacological prophylaxis of venous thromboembolism (VTE) in underweight, critically ill patients is unknown.

OBJECTIVE

To describe prescribing patterns for VTE prophylaxis in underweight (≤50 kg or body mass index ≤18.5 kg/m(2)), critically ill patients and identify the prevalence of VTE and bleeding.

METHODS

This was a retrospective cohort study that included patients who received standard- or reduced-dose VTE prophylaxis for ≥48 hours.

RESULTS

A total of 295 individuals were included in the study. The majority of underweight patients in this study (79.7%) received unfractionated heparin, 5000 units 3 times daily. No statistically significant difference in the prevalence of clinically relevant VTEs between the reduced- and standard-dose groups was observed (4.4% vs 5.6%, P = 1.00), but a higher proportion of bleeding events was identified within the standard-dose group (6.7% vs 11.2%, P = 0.4).

CONCLUSIONS

Empirical dose reductions of VTE prophylaxis are infrequently used in underweight, critically ill patients. Further studies need to be conducted that assess the safety and efficacy of reduced-dose VTE prophylactic regimens in this population to determine if acceptable efficacy can be achieved, with lower risks of bleeding.

Preventing Venous Thromboembolism in the Critically Ill — Can We do More?

Pulmonary embolism is the most common preventable cause of hospital death; and of all the different patient groups, the critically ill are particularly at risk of venous thromboembolism. Most critically ill patients have multiple risk factors. Clinical trials have shown that the use of low molecular weight heparin (LMWH) is safer than unfractionated heparin in this population. Further trials are required to look at the risks and benefits of dose adjusting LMWH at the extremes of weight, in patients with renal failure and those on antiplatelet agents. Heparin-induced thrombocytopenia is still a risk with LMWHs so a safer anticoagulant such as fondaparinux and even the new oral anticoagulants merit trials. Further evidence is also needed for the use of graduated compression stockings and pneumatic devices.

Clinical factors associated with inappropriate prophylaxis of venous thromboembolic disease in critically ill patients. A single day cross-sectional study

PURPOSE

A poor implementation of VTE prophylactic measures recommended for critically ill patients has been observed in several epidemiological studies. The clinical factors associated with this have not been clearly established. The objective of our study was to identify which factors could be related to the inappropriate use of VTE prophylaxis.

METHODS

Analytic epidemiological study based on different aspects of VTE prophylaxis performed on Spanish ICU patients. A multiple logistic regression analysis was conducted to identify the risk factors associated with inappropriate prophylaxis, according to the American College of Chest Physicians 2012 guidelines.

RESULTS

We enrolled 777 patients. On admission, 62% presented medical, 30% surgical and 8% major trauma pathology. Of all patients, 41% were receiving an inappropriate prophylaxis, including 19% which did not receive any prophylaxis. The presence of a contraindication for pharmacological prophylaxis (OR 3.91, 95% CI 2.50-6.10) and non-medical pathology at ICU admission (OR 11.09; 95% CI 7.63-16.12) were associated with inappropriate prophylaxis. In contrast, mechanical ventilation (OR 0.70, 95% CI 0.45-0.98), bed rest>48h (OR 0.61, 95% CI 0.49-0.98), the use of a protocol for VTE prophylaxis (OR 0.66, 95% CI 0.45-0.98) and a VTE risk scoring system (OR 0.49, 95% CI 0.24-0.98) were associated with adequate prophylaxis.

CONCLUSIONS

Our study highlighted a poor compliance with the VTE prophylaxis recommendations proposed for critical patients. The implementation of specific protocols for prophylaxis that include a correct evaluation according to VTE and haemorrhage risk, would allow for optimisation of mechanical and combined prophylaxis, improving adherence to the clinical practice guidelines.

Comparing effects of different routes of heparin administration on the serum biomarkers of thrombosis

BACKGROUND

Association between thrombosis pathogenesis and inflammatory conditions has been reported. Also inflammatory biomarkers have been proposed for prediction of thrombosis events.

OBJECTIVES

Effects of different methods of heparin administration (subcutaneous vs continuous infusion) as thromboprophylaxis on the biomarkers of thrombosis have been evaluated.

METHODS

Serum levels of hsCRP, IL-10 and P-selectin as the biomarkers of thrombosis were measured at baseline, days 3 and 7 during the patients' hospitalization period.

RESULTS

Changes in the serum levels of thrombosis biomarkers (hsCRP, IL-10 and P-selectin) were comparable between the subcutaneous and continuous infusion groups.

CONCLUSION

Both subcutaneous injection and continuous infusion of heparin as thromboprophylaxis showed same effects on the thrombosis biomarkers.

Thrombotic events as incidental finding on computed tomography in intensive care unit patients

INTRODUCTION

Intensive care unit (ICU) patients are a risk group to develop thrombosis and/or thromboembolism. The purpose of this study was to analyze the frequency and localization of clinically silent thrombotic events (TE) detected on CT.

MATERIALS AND METHODS

From 2006 to 2013 a total of 370 patients from the ICU of our university clinic were investigated by postcontrast CT. In all cases CT was performed for detecting septic foci. There were 135 women and 235 men. CT scans included cervical, thoracic, abdominal, and pelvic regions. CT images of all patients were re-interpreted by 2 radiologists by consensus. Only thromboses detected for the first time on CT were included into the analysis. Collected data were evaluated by means of descriptive statistics. Frequencies and localizations of TE in surgical and non surgical patients were analyzed by Chi-square test. Significance level was p<0.05.

RESULTS

In 31.9% several TE were diagnosed. There were venous thrombosis (89.8%), cardiac thrombus (2.6%), and pulmonary embolism (7.6%). More often jugular veins were affected followed by brachiocephalic veins, and iliac veins. The frequency of TE in surgical patients was 31.1%, and 32.1% in non surgical patients. Patients after surgery had more often thrombosis of extremities veins in comparison to non surgical patients. In 61.9% of all TE the identified thrombotic complications were not diagnosed at the time of CT investigations.

CONCLUSION

TE can be identified in 31.9% of ICU patients as incidental finding on CT. There were venous thromboses, pulmonary embolism, and cardiac thrombus. Most frequently neck and thoracic veins were affected. 61.9% of all TE were not diagnosed at the time of CT investigations. Radiologists should check carefully CT scans for presence of different TE.

Improvement of the safety of a clinical process using failure mode and effects analysis: Prevention of venous thromboembolic disease in critical patients

OBJECTIVE

To improve critical patient safety in the prevention of venous thromboembolic disease, using failure mode and effects analysis as safety tool.

DESIGN

A contemporaneous cohort study covering the period January 2014-March 2015 was made in 4 phases: phase 1) prior to failure mode and effects analysis; phase 2) conduction of mode analysis and implementation of the detected improvements; phase 3) evaluation of outcomes, and phase 4) (post-checklist introduction impact.

SETTING

Patients admitted to the adult polyvalent ICU of a third-level hospital center.

PATIENTS

A total of 196 patients, older than 18 years, without thromboembolic disease upon admission to the ICU and with no prior anticoagulant treatment.

INTERVENTIONS

A series of interventions were implemented following mode analysis: training, and introduction of a protocol and checklist to increase preventive measures in relation to thromboembolic disease.

VARIABLES OF INTEREST

Indication and prescription of venous thrombosis prevention measures before and after introduction of the measures derived from the failure mode and effects analysis.

RESULTS

A total of 59, 97 and 40 patients were included in phase 1, 3 and 4, respectively, with an analysis of the percentage of subjects who received thromboprophylaxis. The failure mode and effects analysis was used to detect potential errors associated to a lack of training and protocols referred to thromboembolic disease. An awareness-enhancing campaign was developed, with staff training and the adoption of a protocol for the prevention of venous thromboembolic disease. The prescription of preventive measures increased in the phase 3 group (91.7 vs. 71.2%, P=.001). In the post-checklist group, prophylaxis was prescribed in 97.5% of the patients, with an increase in the indication of dual prophylactic measures (4.7, 6.7 and 41%; P<.05). There were no differences in complications rate associated to the increase in prophylactic measures.

CONCLUSIONS

The failure mode and effects analysis allowed us to identify improvements in the prevention of thromboembolic disease in critical patients. We therefore consider that it may be a useful tool for improving patient safety in different processes.

Comparing safety of heparin as continuous intravenous infusion and multiple subcutaneous injections

AIM

In this study, safety of two methods of unfractionated heparin administration for venous thromboembolism prophylaxis was compared in critically ill surgical patients.

METHODS

A total of 50 surgical critically ill patients randomly assigned to either subcutaneous unfractionated heparin 5000 units three-times a day or continuous intravenous infusion; 625 IU/h. During the intensive care unit (ICU) stay, patients' hemodynamic parameters, laboratory tests, symptoms and signs of thrombosis and bleeding were monitored closely.

RESULTS

During the patients' follow-up, no episode of bleeding or venous thromboembolism event was recorded. The differences in ICU and hospital stays were not significantly different between the groups.

CONCLUSION

There are limited evidences regarding safety and efficacy of continuous intravenous infusion of unfractionated heparin for thromboprophylaxis.

Venous Thromboembolism in Critically Ill Medical Patients Receiving Chemoprophylaxis

Purpose:

To compare the incidence of 90-day venous thromboembolism (VTE) in obese critically ill medical patients receiving VTE chemoprophylaxis with nonobese patients of similar illness severity. We also identified other VTE risk factors.

Methods:

Eligible patients spent ≥24 hours in an intensive care unit between November 2007 and November 2013 and received VTE chemoprophylaxis within 48 hours of admission. The primary outcome was 90-day VTE.

Results:

A total of 11 111 patients were evaluated, of which 1732 obese and 1831 nonobese patients were enrolled with mean BMIs of 38.9 ± 9.2 kg/m2 and 24.5 ± 3.1 kg/m2 and mean Acute Physiology and Chronic Health Evaluation II scores of 28.4 ± 11.8 and 26.6 ± 11.7, respectively. The rate of 90-day VTE for the total cohort, obese, and nonobese patients was 6.5%, 7.5%, and 5.5%, respectively. Obese patients were more likely to develop VTE compared with nonobese patients (odds ratio [OR]: 1.41; 95% confidence interval [CI]: 1.03 -1.93). Other risk factors significantly associated with 90-day VTE included prior VTE (OR: 3.93; 95% CI: 1.83-8.48), trauma with surgery in the previous 30 days (OR: 3.70; 95% CI: 1.39-9.86), central venous catheters (OR: 2.64; 95% CI: 1.87-3.72), surgery within 90 days (OR: 2.40; 95% CI: 1.61-3.58), mechanical ventilation (OR: 1.94; 95% CI: 1.39-2.71), male sex (OR: 1.55; 95% CI: 1.13-2.14), and increasing age using 1-year increments (OR: 1.02; 95% CI: 1.01 -1.03).

Conclusions:

The rate of VTE in critically ill medical patients remains high despite standard chemoprophylaxis. Obesity is among 8 risk factors independently associated with 90-day VTE.

Competing Risk Analysis for Evaluation of Dalteparin Versus Unfractionated Heparin for Venous Thromboembolism in Medical-Surgical Critically Ill Patients

Failure to recognize the presence of competing risk or to account for it may result in misleading conclusions. We aimed to perform a competing risk analysis to assess the efficacy of the low molecular weight heparin dalteparin versus unfractionated heparin (UFH) in venous thromboembolism (VTE) in medical-surgical critically ill patients, taking death as a competing risk.This was a secondary analysis of a prospective randomized study of the Prophylaxis for Thromboembolism in Critical Care Trial (PROTECT) database. A total of 3746 medical-surgical critically ill patients from 67 intensive care units (ICUs) in 6 countries receiving either subcutaneous UFH 5000 IU twice daily (n = 1873) or dalteparin 5000 IU once daily plus once-daily placebo (n = 1873) were included for analysis.A total of 205 incident proximal leg deep vein thromboses (PLDVT) were reported during follow-up, among which 96 were in the dalteparin group and 109 were in the UFH group. No significant treatment effect of dalteparin on PLDVT compared with UFH was observed in either the competing risk analysis or standard survival analysis (also known as cause-specific analysis) using multivariable models adjusted for APACHE II score, history of VTE, need for vasopressors, and end-stage renal disease: sub-hazard ratio (SHR) = 0.92, 95% confidence interval (CI): 0.70-1.21, P-value = 0.56 for the competing risk analysis; hazard ratio (HR) = 0.92, 95% CI: 0.68-1.23, P-value = 0.57 for cause-specific analysis. Dalteparin was associated with a significant reduction in risk of pulmonary embolism (PE): SHR = 0.54, 95% CI: 0.31-0.94, P-value = 0.02 for the competing risk analysis; HR = 0.51, 95% CI: 0.30-0.88, P-value = 0.01 for the cause-specific analysis. Two additional sensitivity analyses using the treatment variable as a time-dependent covariate and using as-treated and per-protocol approaches demonstrated similar findings.This competing risk analysis yields no significant treatment effect on PLDVT but a superior effect of dalteparin on PE compared with UFH in medical-surgical critically ill patients. The findings from the competing risk method are in accordance with results from the cause-specific analysis.clinicaltrials.gov Identifier: NCT00182143.

Pharmacokinetic considerations for drugs administered in the critically ill

Significant physiological changes are common among critically ill patients. This case-based review describes the consequences of these changes on the selection and dosing of medications.

Economic evaluation of the prophylaxis for thromboembolism in critical care trial (E-PROTECT): study protocol for a randomized controlled trial

Background

Venous thromboembolism (VTE) is a common complication of critical illness with important clinical consequences. The Prophylaxis for ThromboEmbolism in Critical Care Trial (PROTECT) is a multicenter, blinded, randomized controlled trial comparing the effectiveness of the two most common pharmocoprevention strategies, unfractionated heparin (UFH) and low molecular weight heparin (LMWH) dalteparin, in medical-surgical patients in the intensive care unit (ICU). E-PROTECT is a prospective and concurrent economic evaluation of the PROTECT trial.

Methods/Design

The primary objective of E-PROTECT is to identify and quantify the total (direct and indirect, variable and fixed) costs associated with the management of critically ill patients participating in the PROTECT trial, and, to combine costs and outcome results to determine the incremental cost-effectiveness of LMWH versus UFH, from the acute healthcare system perspective, over a data-rich time horizon of ICU admission and hospital admission. We derive baseline characteristics and probabilities of in-ICU and in-hospital events from all enrolled patients. Total costs are derived from centers, proportional to the numbers of patients enrolled in each country. Direct costs include medication, physician and other personnel costs, diagnostic radiology and laboratory testing, operative and non-operative procedures, costs associated with bleeding, transfusions and treatment-related complications. Indirect costs include ICU and hospital ward overhead costs. Outcomes are the ratio of incremental costs per incremental effects of LMWH versus UFH during hospitalization; incremental cost to prevent a thrombosis at any site (primary outcome); incremental cost to prevent a pulmonary embolism, deep vein thrombosis, major bleeding event or episode of heparin-induced thrombocytopenia (secondary outcomes) and incremental cost per life-year gained (tertiary outcome). Pre-specified subgroups and sensitivity analyses will be performed and confidence intervals for the estimates of incremental cost-effectiveness will be obtained using bootstrapping.

Discussion

This economic evaluation employs a prospective costing methodology concurrent with a randomized controlled blinded clinical trial, with a pre-specified analytic plan, outcome measures, subgroup and sensitivity analyses. This economic evaluation has received only peer-reviewed funding and funders will not play a role in the generation, analysis or decision to submit the manuscripts for publication.

Trial registration

Clinicaltrials.gov Identifier: NCT00182143. Date of registration: 10 September 2005.

Electronic supplementary material

The online version of this article (doi:10.1186/1745-6215-15-502) contains supplementary material, which is available to authorized users.

Prevention of venous thromboembolism in medical intensive care unit: a multicenter observational study in Korea

Patients admitted to medical intensive care unit (MICU) are at increased risk for venous thromboembolism (VTE); and prophylaxis is recommended. However, the actual range and frequency of VTE prophylaxis administered to MICU patients are not well defined. Patients over 40 yr of age and expected MICU stay of more than 48 hr were eligible for this observational cohort study of 23 MICUs in Korea. Patients already on anticoagulation therapy or those requiring anticoagulation for reasons other than VTE were excluded. Among 830 patients, VTE prophylaxis was given to 560 (67.5%) patients. Among 560 patients, 323 (38.9%) received pharmacoprophylaxis, 318 (38.4%) received mechanical prophylaxis and 81 (9.8%) received both forms of prophylaxis. About 74% of patients in the pharmacoprophylaxis group received low molecular weight heparin and 53% of the patients in the mechanical prophylaxis group used intermittent pneumatic compression. Most of the patients (90%) had more than one risk factor for VTE and the most common risk factor was old age, followed by heart and respiratory failure. In this observational cohort study of 23 MICUs in Korea, 67.5% of patients received thromboprophylaxis. Further studies are needed to clarify the role and efficacy of VTE prophylaxis in Korean critically ill patients.

Venous thromboembolism risk assessment, prophylaxis practices and interventions for its improvement (AVAIL-ME Extension Project, Iran)

BACKGROUND

Venous thromboembolism (VTE) is a major health issue worldwide. Data about VTE prophylaxis practices in developing countries are scarce.

OBJECTIVES

The primary objectives of this survey were to define the VTE risk factors in hospitalized patients, to determine the rates of VTE prophylaxis administration and guideline compliance and to assess the effects of an educational program on VTE prophylaxis practices in Iran.

PATIENTS AND METHODS

Data on 1219 patients from twenty hospitals in Iran were extracted from the AVAIL-ME Extension project main databank. VTE risks were categorized according to the Caprini Risk Assessment Model. Logistic regression analysis was carried out to assess factors influencing VTE prophylaxis. We also examined the impact of an educational program which consisted of awareness, risk assessment, internal protocol implementation and re-assessment, on VTE prophylaxis practices.

RESULTS

Of 1219 patients, 789 (65%) and 430 (35%) were surgical and medical, respectively. VTE risks, categorized in low, moderate, high and very high were detected in 14%, 17%, 26% and 43% of patients respectively with a total of 1042(85%) patients being at risk for VTE. Of 882 (85%) eligible patients for VTE prophylaxis, 737 (83.5%) received any drug prophylaxis of whom 265 (62%) were medical and 472 (60%) were surgical. ACCP guidelines compliance was 60% and 33% in surgical and medical patients respectively. Any VTE prevention, drug prophylaxis, mechanical prophylaxis and guideline adherence were, 48% vs. 64%, 45% vs. 60%, 6% vs. 9% and 34% vs. 45% respectively (p<00.1) before and after implementation of the VTE educational program.

CONCLUSIONS

Despite an overall improvement in VTE prevention, areas such as inappropriate use of VTE prophylaxis in a large number of patients, significant under-use of mechanical devices and guideline adherence require closer attention. VTE awareness education is beneficial in improving VTE prophylaxis in Iran.

[Prevention of venous thromboembolic disease in the critical patient: an assessment of clinical practice in the Community of Madrid]

OBJECTIVE

To analyze measures referred to venous thromboembolic prophylaxis in critically ill patients.

DESIGN

An epidemiological, cross-sectional (prevalence cut), multicenter study was performed using an electronic survey. Comparison of results with quality indexes of the Spanish Society of Intensive Care Medicine, the American College of Chest Physician guidelines and international studies.

SETTING

Intensive Care Units (ICUs) in the Community of Madrid (Spain).

PATIENTS

All patients admitted to the ICU on the day of the survey.

VARIABLES OF INTEREST

General aspects of venous thromboembolic prophylaxis and protocols used (risk stratification and ultrasound screening). A descriptive analysis was performed, continuous data being expressed as the mean or median, and categorical data as percentages.

RESULTS

A total of 234 patients in 18 ICUs were included. Eighteen percent (42/234) received no prophylaxis, and 55% had no contraindication to pharmacological prophylaxis. Of the 192 patients receiving prophylaxis, 84% received pharmacological prophylaxis, 14% mechanical prophylaxis and 2% combined prophylaxis. Low molecular weight heparin was the only pharmacological prophylaxis used, with a majority use of enoxaparin (17 of 18 ICUs). In patients with mechanical prophylaxis (31/192), antiembolic stockings were the most commonly used option (58%). Pharmacological prophylaxis contraindications were reported in 20% of the patients (46/234), the most frequent cause being thrombocytopenia (28% of the cases). Fifty percent of the ICUs used no specific venous thromboembolic prophylaxis protocol.

CONCLUSIONS

Pharmacological prophylaxis with low molecular weight heparin was the most frequently used venous thromboembolic prophylactic measure. In patients with contraindications to pharmacological prophylaxis, mechanical measures were little used. The use of combined prophylaxis was anecdotal. Many of our ICUs lack specific prophylaxis protocols.

Frequency of hypoxic events in patients on a mechanical ventilator

Background:

Mechanical ventilation is an important tool in the management of respiratory failure in the critically ill patient. Although mechanical ventilation can be a life-saving intervention, it is also known to carry several side-effects and risks. Adequate oxygenation is one of the primary goals of mechanical ventilation. However, while on mechanical ventilation, patients frequently experience hypoxic events resulting from various causes, which need to be properly evaluated and treated.

Materials and Methods:

Data were obtained by prospectively reviewing all intensive care admissions during the period from March 2009 to March 2010 at a 651-bed urban medical center. Patients who developed hypoxemia (oxygen saturation ≤88% and a PaO₂≤60 torrs) while on mechanical ventilation were investigated for the cause of hypoxic event.

Results:

During the study period, 955 patients required mechanical ventilation from which 79 developed acute hypoxia. The causes of acute hypoxia in decreasing order of occurrences were pulmonary edema, atelectasis, pneumothorax, pneumonia, ARDS, endotracheal tube malfunction, airway bleeding, and pulmonary embolism.

Conclusions:

Appropriate evaluation of all hypoxic events must begin at the bedside. A step-by-step approach must include a thorough physical examination. Evaluation of the endotracheal tube can immediately reveal dislodgement, bleeding, and secretions. Correlation of physical examination findings with those on chest radiograph is essential. Each hypoxic event requires a different intervention depending on its etiology. Instead of simply increasing the fraction of oxygen in the inspired air to overcome hypoxia, a concerted effort in appropriate problem solving can reduce the likelihood of an incorrect diagnosis and management response.

Pulmonary Embolism in the Mechanically-Ventilated Critically Ill Patient: Is it Different?

Pulmonary embolism (PE) confers significant in-hospital morbidity and mortality, and critically ill patients remain at risk for venous thromboembolism despite thromboprophylaxis. Recognition of the clinical manifestations and immediate management of PE are of paramount importance. Despite diagnostic advances, PE is often undiagnosed and untreated in patients receiving mechanical ventilation, as these patients do not exhibit the common clinical features of the condition, making the diagnosis very challenging. Computed tomographic pulmonary angiography is probably the reference standard for the diagnosis of acute PE in the haemodynamically stable, ventilated patient. In the setting of circulatory collapse, bedside echocardiography may be used to risk stratify these patients, based on the presence or absence of right ventricular dysfunction, and guide further management. Treatment options include anticoagulation alone, anticoagulation plus thrombolysis, surgical or catheter embolectomy. Inotropes, vasopressors and pulmonary artery vasodilators may be considered after initial resuscitation of the right ventricle. Few studies have focused on estimating the prevalence of PE among mechanically-ventilated intensive care unit (ICU) patients and there is notable lack of data assessing predictive factors, prevention, diagnostic strategy and management of PE in the ICU setting.

Venous thromboembolism in the Get With The Guidelines-Stroke acute ischemic stroke population: incidence and patterns of prophylaxis

BACKGROUND

Venous thromboembolism (VTE), which includes deep vein thrombosis (DVT) and pulmonary embolus (PE), represents a serious complication in hospitalized ischemic stroke patients. This study examines the incidence of VTE and the patterns of VTE prophylaxis in acute ischemic stroke patients deemed appropriate for VTE prophylaxis (nonambulatory) in the Get With The Guidelines-Stroke (GWTG-S) study.

METHODS

We analyzed data from 149,916 patients who were admitted with acute ischemic stroke and enrolled in GWTG-S from 1259 U.S. hospitals. Patient variables and site characteristics were analyzed in relation to reported administration of VTE prophylaxis.

RESULTS

The overall rate of VTE prophylaxis in the analysis cohort was 93% (139,476/149,916). The median site prophylaxis rate was 95%, and prophylaxis rates ranged from 17% (1 site) to 100% (101 sites). Factors associated with increased likelihood of VTE prophylaxis in the multivariable model included history of atrial fibrillation/flutter, receipt of intravenous or intra-arterial tissue plasminogen activator, and admission to an academic hospital. Increasing age, black race, and a history of peripheral vascular disease, diabetes, or stroke were associated with lower likelihood of prophylaxis. Patients receiving care in the Midwest were less likely to receive prophylaxis compared to other regions.

CONCLUSIONS

Despite a high overall rate of VTE prophylaxis, VTE was found to occur in approximately 3% of GWTG-S patients. Reported rates of VTE prophylaxis differed among hospitals by region and hospital type, and among patients by age, race, and medical comorbidities.

[Risk factors and features of critically ill patients with deep vein thrombosis in lower extremities]

PURPOSE

The purpose of this study was to identify the features, risk scores and risk factors for deep vein thrombosis in critically ill patients who developed deep vein thrombosis in their lower extremities.

METHODS

The participants in this prospective descriptive study were 175 adult patients who did not receive any prophylactic medication or mechanical therapy during their admission in the intensive care unit.

RESULTS

The mean age was 62.24 (±17.28) years. Men made up 54.9% of the participating patients. There were significant differences in age, body mass index, and leg swelling between patients who developed deep vein thrombosis and those who did not have deep vein thrombosis. The mean risk score was 6.71(±2.94) and they had on average 4.01(±1.35) risk factors. In the multiple logistic regression, body mass index (odds ratio=1.14) and leg swelling (odds ratio=6.05) were significant predictors of deep vein thrombosis.

CONCLUSION

Most critically ill patients are in the potentially high risk group for deep vein thrombosis. However, patients who are elderly, obese or have leg edema should be closely assessed and more than one type of active prophylactic intervention should be provided.

Risk factors and incidence of deep vein thrombosis in lower extremities among critically ill patients

AIMS AND OBJECTIVES

To investigate how many critically ill patients developed deep vein thrombosis (DVT) during their admission to intensive care units (ICU) and to compare the characteristics of patients with and without deep vein thrombosis.

BACKGROUND

Critically ill patients are a high-risk group for deep vein thrombosis because they typically have multiple risk factors, such as prolonged immobility, mechanical ventilation and old age.

DESIGN

A prospective observational study was employed.

METHODS

The subjects were 90 patients who were older than 18 years of age, who were admitted to an intensive care unit for more than five days and were not provided any prophylactic measures. Data were collected at a university hospital for five months. A duplex scan was performed on day 2.4 on average and repeated between days 5-7 to diagnose deep vein thrombosis. The iliac, femoral, popliteal and tibial veins were examined by compression and colour Doppler methods of the duplex scan by one technician.

RESULTS

Age, gender and body mass index were significant factors for deep vein thrombosis development (p < 0.05). Ten patients (11.1%) developed deep vein thrombosis during their stay in the intensive care units.

CONCLUSIONS

The incidence was lower than in Western studies in which patients were not provided prophylaxis, but may increase with an extended observation period as in previous studies.

RELEVANCE TO CLINICAL PRACTICE

The results of this study could allow ICU nurses to recognise the DVT incidence in critically ill patients. This result could lead to more active prevention and monitoring of DVT by ICU nurses, especially for high-risk patients, such as older or obese patients.

Total-to-ionized calcium ratio predicts mortality in continuous renal replacement therapy with citrate anticoagulation in critically ill patients

INTRODUCTION

Regional citrate anticoagulation is safe, feasible and increasingly used in critically ill patients on continuous renal replacement therapy (CRRT). However, in patients with hepatic or multi-organ dysfunction, citrate accumulation may lead to an imbalance of calcium homeostasis. The study aimed at evaluating the incidence and prognostic relevance of an increased total to ionized calcium ratio (T/I Ca(2+) ratio) and its association to hepatic dysfunction.

METHODS

We performed a prospective observational study on n = 208 critically ill patients with acute kidney injury (AKI) and necessity for CRRT with regional citrate anticoagulation (CRRT-citrate) between September 2009 and September 2011. Critical illness was estimated by Simplified Acute Physiology Score II; hepatic function was measured with indocyanine green plasma disappearance rate. After achieving a steady state of calcium homeostasis patients were classified into tertiles according to the T/I Ca(2+) ratio (<2.0 versus 2.0 - 2.39 versus ≥ 2.4).

RESULTS

The T/I Ca(2+) ratio was determined as an independent predictor for 28-day mortality in critically ill patients with AKI on CRRT-citrate confirmed by receiver operating characteristics and multivariate analysis (Area under the curve 0.94 ± 0.02; p<0.001). A T/I Ca(2+) ratio ≥ 2.4 independently predicted a 33.5-fold (p<0.001) increase in 28-day mortality-rate. There was a significant correlation between the T/I Ca(2+) ratio and the hepatic clearance (p<0.001) and the severity of critical illness (p<0.001). The efficacy and safety of citrate anticoagulation, determined by blood urea nitrogen, mean filter patency and bleeding episodes, were not significantly different between the tertiles.

CONCLUSIONS

In patients on CRRT-citrate T/I Ca(2+) ratio is closely related to the clinical outcome and emerged as an independent predictor of 28-day mortality. Larger studies are required to define the cut-off and predictive value for the T/I Ca(2+) ratio. This ratio is associated with hepatic and/or multi-organ dysfunction and therefore an important therapeutic target.