Thromboprophylaxis for intensive care patients in Australia and New Zealand: a brief survey report

Current Practice of Pharmacological Thromboprophylaxis for Prevention of Venous Thromboembolism in Hospitalized Children: A Survey of Pediatric Hemostasis and Thrombosis Experts in North America

Pharmacological thromboprophylaxis (pTP) is the most effective intervention to prevent venous thromboembolism (VTE) in hospitalized adults. High-quality studies investigating the role of pTP in children are lacking. The aim of this study is to understand pediatric hematologists' current practices of pTP prescription and to explore their opinion about universal adoption of pTP for high-risk hospitalized children. An electronic survey was sent to members of Hemostasis and Thrombosis Research Society of North America. The response rate was 47.3% (53/112). VTE was perceived as a major hospital acquired complication by all and 96% (51/53) prescribed pTP in select cases. Majority would consider prescribing pTP for personal history of thrombosis, inheritance of severe thrombophilic conditions, and teen age. The majority of respondents (55%, 29/53) were either not in support of or uncertain about the universal adoption of pTP policy for high-risk hospitalized children. In total, 62% of respondents (33/53) did not support the use of pTP for central venous lines. Respondents reported on the presence of pharmacological (32%, 17/53) and mechanical (45%, 24/53) thromboprophylaxis policies at their institutions. Pediatric hematologists considered pTP a useful intervention to prevent VTE and prescribed pTP in select cases. Universal adoption of pTP was not supported. Wide variability in clinical practice was observed.

Physicians declining patient enrollment in a critical care trial: a case study in thromboprophylaxis

PURPOSE

To analyze the frequency, rationale and determinants of attending physicians requesting that their eligible patients not be approached for participation in a thromboprophylaxis trial.

METHODS

Research personnel in 67 centers prospectively documented eligible non-randomized patients due to physicians declining to allow their patients to be approached.

RESULTS

In 67 centers, 3,764 patients were enrolled, but 1,460 eligible patients had no consent encounter. For 218 (14.9 %) of these, attending physicians requested that their patients not be approached. The most common reasons included a high risk of bleeding (31.2 %) related to fear of heparin bioaccumulation in renal failure, the presence of an epidural catheter, peri-operative status or other factors; specific preferences for thromboprophylaxis (12.4 %); morbid obesity (9.6 %); uncertain prognosis (6.4 %); general discomfort with research (3.7 %) and unclear reasons (17.0 %). Physicians were more likely to decline when approached by less experienced research personnel; considering those with[10 years of experience as the reference category, the odds ratios (OR) for physician refusals to personnel without trial experience was 10.47 [95 % confidence interval (CI) 2.19-50.02] and those with less than 10 years experience was 1.72 (95 % CI 0.61-4.84). Physicians in open rather than closed units were more likely to decline (OR 4.26; 95 % CI 1.27-14.34). Refusals decreased each year of enrollment compared to the pilot phase.

CONCLUSIONS

Tracking, analyzing, interpreting and reporting the rates and reasons for physicians declining to allow their patients to be approached for enrollment provides insights into clinicians' concerns and attitudes to trials. This information can encourage physician communication and education, and potentially enhance efficient recruitment.

Newer anticoagulants in critically ill patients

Critically ill patients are at increased risk for development of thrombosis. In addition, thrombosis is often unrecognized in this population. Furthermore, these patients are particularly susceptible to bleeding complications from anticoagulants. Herein the authors review the pharmacology, data from clinical trials, management of bleeding complications, and perioperative use of these agents in the intensive care unit population. Well-designed clinical trials are needed to improve our understanding of the safety and efficacy of these newer agents in critically ill patients.

Survey of pharmacologic thromboprophylaxis in critically ill children

OBJECTIVE

There is lack of evidence to guide thromboprophylaxis in the pediatric intensive care unit. We aimed to assess current prescribing practice for pharmacologic thromboprophylaxis in critically ill children.

SETTING

Pediatric intensive care units in the United States and Canada with at least ten beds.

DESIGN

Cross-sectional self-administered survey of pediatric intensivists using adolescent, child, and infant scenarios.

PARTICIPANTS

Pediatric intensive care unit clinical directors or section heads.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Physician leaders from 97 of 151 (64.2%) pediatric intensive care units or their designees responded to the survey. In mechanically ventilated children, 42.3% of the respondents would usually or always prescribe thromboprophylaxis for the adolescent but only 1.0% would prescribe it for the child and 1.1% for the infant. Considering all pediatric intensive care unit patients, 3.1%, 32.0%, and 44.2% of respondents would never prescribe thromboprophylaxis for the adolescent, child, and infant scenarios, respectively. These findings were significant (p < .001 for the adolescent vs. child and infant; p = .002 for child vs. infant). Other patient factors that increased the likelihood of prescribing prophylaxis to a critically ill child for all three scenarios were the presence of hypercoagulability, prior deep venous thrombosis, or a cavopulmonary anastomosis. Prophylaxis was less likely to be prescribed to patients with major bleeding or an anticipated invasive intervention. Low-molecular-weight heparin was the most commonly prescribed drug.

CONCLUSIONS

In these scenarios, physician leaders in pediatric intensive care units were more likely to prescribe thromboprophylaxis to adolescents compared with children or infants, but they prescribed it less often in adolescents than is recommended by evidence-based guidelines for adults. The heterogeneity in practice we documented underscores the need for rigorous randomized trials to determine the need for thromboprophylaxis in critically ill adolescents and children.

PROphylaxis for ThromboEmbolism in Critical Care Trial protocol and analysis plan

BACKGROUND

This article reports the preparatory studies as well as the design, implementation, and a priori analysis plans of PROphylaxis for ThromboEmbolism in Critical Care Trial (PROTECT) before dissemination of results. PROphylaxis for ThromboEmbolism in Critical Care Trial (NCT00182143) is a randomized, stratified, concealed international trial comparing subcutaneous injection of unfractionated heparin (UFH) 5000 IU or the low-molecular weight heparin (LMWH) dalteparin 5000 IU once daily plus once-daily placebo for the duration of the intensive care unit stay.

METHODS

The objective of PROTECT is to examine, among medical-surgical critically ill patients, the effect of the LMWH vs heparin on the primary outcome of proximal leg deep vein thrombosis (DVT) and the following secondary outcomes: DVT elsewhere, pulmonary embolism, any venous thromboembolism (DVT or pulmonary embolism), the composite of venous thromboembolism or death, bleeding, and heparin-induced thrombocytopenia. Patients are followed up to death or hospital discharge. Venous thromboembolism events were included after intensive care unit discharge. All patients, families, clinicians, research personnel, and the trial biostatistician are blind to allocation.

RESULTS

We describe the pilot work, large trial methodology, implementation methods, and the analytic plan. Patient recruitment is complete, but 2 patients remain in the hospital. The rigorous design of PROTECT suggests that the risk of systematic error will be low. The sample size suggests that the risk of random error will be low. PROTECT will be the largest investigator-initiated peer-review funded thromboprophylaxis trial in critical care in the world.

CONCLUSIONS

If PROTECT shows that LMWH is more effective than UFH, this trial will change practice in that LMWH may be the anticoagulant thromboprophylaxis of choice for this population. If the results show that UFH is as effective or more effective than LMWH, intensivists in many parts of the world may continue to use UFH, whereas those currently using LMWH may reconsider and change to use UFH. Unfavorable consequences such as major bleeding, ease of use, and the costs of complications will also factor into such decisions.

Low-molecular-weight heparin thromboprophylaxis in medical-surgical critically ill patients: a systematic review

PURPOSE

The study aimed to systematically review the effect of low-molecular-weight heparin (LMWH) thromboprophylaxis in medical-surgical critically ill patients in the intensive care unit.

METHODS

In duplicate and independently, we searched for relevant articles using MEDLINE and EMBASE; we also contacted experts and reviewed reference lists. For included studies, we abstracted data on study and patient characteristics, LMWH use, clinical outcomes (venous thromboembolism [VTE], bleeding, and mortality), laboratory outcomes (anti-Xa levels and thrombocytopenia), and methodological quality.

RESULTS

We included 8 prospective cohort studies and 1 randomized trial, with a total of 629 patients. Eight studies (n = 406 patients) reported anti-Xa levels and only 3 studies (n = 240 patients) reported on at least one clinical outcome. Low-molecular-weight heparin does not appear to bioaccumulate based on repeated measurements of trough anti-Xa levels. Thrombocytopenia occurred in 9.3% of patients receiving LMWH; heparin-induced thrombocytopenia was not reported. In studies reporting clinical outcomes, the frequency of VTE in patients receiving LMWH ranged from 5.1% to 15.5%, bleeding complications ranged from 7.2% to 23.1%, and mortality ranged from 1.4% to 7.4%.

CONCLUSIONS

Low-molecular-weight heparin may be effective for thromboprophylaxis in medical-surgical critically ill patients, but no trials have compared LMWH against an alternative active strategy; thus, LMWH cannot be recommended routinely. Trials testing LMWH thromboprophylaxis are required, which examine patient-important end points such as the incidence and clinical consequences of VTE, bleeding, heparin-induced thrombocytopenia, and mortality.

[Prevention of thromboembolism in German intensive care units : Results of a nationwide survey]

BACKGROUND

Intensive care unit (ICU) patients have a high risk of developing venous thromboembolism (VTE) and prophylaxis is recommended. Venous thromboembolism confers considerable morbidity and mortality in hospitalized patients, although few studies have focused on critically ill patients.

METHOD AND OBJECTIVE

A systematic prospective mailed self-administered survey of 645 German ICU directors was performed, representing 652 ICUs throughout the country. The objective of this study was to understand current approaches to the prevention of VTE among patients in ICUs.

RESULTS

Of the 652 ICUs approached, 470 (72.3%) participated. Thromboembolism prophylaxis was prescribed in 98% of the ICUs. For mechanical prophylaxis graded elastic stockings were used in 93% and pneumatic compression devices in 24%. For pharmacologic prophylaxis low molecular weight heparin was the predominant prophylactic strategy in 88%, whereas unfractionated heparin was used less often in 45%.

CONCLUSION

The prescribed prophylaxis for thromboembolism in 98% of the German ICUs is surprisingly high compared to that given in the literature. A combination of mechanical and pharmacologic prophylaxis is the predominant prophylactic strategy.