An update on prevention of venous thromboembolism in hospitalized acutely ill medical patients

Ultra-Early Venous Thromboembolism (VTE) Prophylaxis in Spontaneous Intracerebral Hemorrhage (sICH)

OBJECTIVE

To determine if ultra-early (<24 h) venous thromboembolism (VTE) prophylaxis was associated with hematoma growth in spontaneous intracerebral hemorrhage (ICH).

BACKGROUND

Patients with ICH have a high risk of VTE. Pharmacological prophylaxis such as unfractionated heparin (UFH) have been demonstrated to reduce VTE. However, published datasets exclude patients with recent ICH out of concern for hematoma enlargement. American Heart/Stroke Association guidelines recommend UFH 1-4 days after hematoma stabilization while the European Stroke Organization has no recommendations on when to begin UFH. Our institutional practice is to obtain stability CT scans at 6 to 24 h and to begin UFH following documented clinical and radiologic stability. We examined the impact of this practice on hematoma expansion.

METHODS

We performed a retrospective cohort analysis of consecutive ICH patients treated at a single tertiary academic referral center in the US. Demographic and clinical characteristics were abstracted. ICH volume was measured via 3D volumetrics for a CT head done on admission, follow-up stability, and prior to discharge. The primary outcome was analyzed as ≥3 mL hematoma enlargement. Secondary outcomes include hematoma expansion of ≥6mL and ≥ 33%, length of stay (LOS), discharge disposition and mortality.

RESULTS

A total of 163 ICH patients were analyzed. There were 58 (35.6%) patients in the ultra-early UFH group and UFH was initiated on average at 13.8 h from initial scan. There were 105 (64.6%) patients in the standard group who initiated UFH at an average of 46.6 h. The primary outcome of hematoma enlargement ≥3 mL was observed in 2/58(3.4%) patients with ultra-early initiation of UFH and in 7/105(6.7%) in the standard group (p=0.49). Secondary outcomes were not significant including hematoma expansion in the ultra-early group ≥ 6 mL 3/58 (5.2%) and ≥33% 7/58 (12.1%) (p=0.91, 0.61, respectively) as well as mortality or LOS.

CONCLUSION

Venous thromboembolism prophylaxis started ultra-early (≤24 h) after ICH was not associated with hematoma expansion.

Venous thromboembolism prophylaxis in hospitalized elderly patients: Time to consider a 'MUST' strategy

Venous thromboembolism (VTE) is the commonest cause of preventable death in hospitalized patients. Elderly patients have higher risk of VTE because of the high prevalence of predisposing co-morbidities and acute illnesses. Clinical diagnosis of VTE in the elderly patient is particularly difficult and, as such, adequate VTE prophylaxis is of pivotal importance in reducing the mortality and morbidities of VTE. Omission of VTE prophylaxis is, however, very common despite continuous education. A simple way to overcome this problem is to implement universal VTE prophylaxis for all hospitalized elderly patients instead of selective prophylaxis for some patients only according to individual's risk of VTE. Although pharmacological VTE prophylaxis is effective for most patients, a high prevalence of renal impairment and drug interactions in the hospitalized elderly patients suggests that a multimodality approach may be more appropriate. Mechanical VTE prophylaxis, including calf and thigh compression devices and/or an inferior vena cava filter, are often underutilized in hospitalized elderly patients who are at high-risk of bleeding and VTE. Because pneumatic compression devices and thigh length stockings are virtually risk free, mechanical VTE prophylaxis may allow early or immediate implementation of VTE prophylaxis for all hospitalized elderly patients, regardless of their bleeding and VTE risk. Although the cost-effectiveness of this Multimodality Universal STat (‘MUST’) VTE prophylaxis approach for hospitalized elderly patients remains uncertain, this strategy appears to offer some advantages over the traditional ‘selective and single-modal’ VTE prophylaxis approach, which often becomes ‘hit or miss’ or not implemented promptly in many hospitalized elderly patients. A large clustered randomized controlled trial is, however, needed to assess whether early, multimodality, universal VTE prophylaxis can improve important clinical outcomes of hospitalized elderly patients.

Low-molecular-weight heparin in patients with advanced cirrhosis

BACKGROUND & AIMS

The use of low-molecular-weight heparins (LMWH) in patients with advanced liver diseases is frequently avoided because of the enhanced risk of bleeding complications. However, many patients with impaired liver function are at a high risk of thrombosis or have an indication for therapeutic anticoagulation. Therefore, the aim of this study was to evaluate the pharmacokinetics of LMWH in patients with cirrhosis.

METHODS

Eighty-four consecutive patients with cirrhosis and a clinical indication for prophylactic or therapeutic anticoagulation were included. The LMWH doses were chosen according to current guidelines. Antifactor Xa activity (anti-Xa) was assessed on two consecutive days, 4 h after drug administration. The severity of liver disease was quantified using Child-Turcotte-Pugh score, the MELD score and clinical features and was correlated with the anti-Xa value and the occurrence of complications.

RESULTS

Antifactor Xa activity was negatively correlated with the severity of the liver disease, and a positive correlation was observed between antithrombin-III (AT) levels and anti-Xa value. AT itself was negatively correlated with the severity of liver disease. Seven patients had an episode of variceal bleeding. No patient died during the observation interval and no thromboembolic events occurred.

CONCLUSION

Prophylactic use of LMWH in patients with cirrhosis appears to be safe. A decreased anti-Xa value in cirrhotic patients and a negative correlation with liver function challenge the unconditional use of anti-Xa assays in LMWH monitoring in cirrhotic patients and reveals a potential limitation of anti-Xa analysis in these patients. Low levels of AT, because of reduced hepatic synthesis, are the most likely cause of this phenomenon.