Ak Hiett

Deep vein thrombosis and pulmonary embolism in pregnancy: diagnosis, complications, and management.

Venous thromboembolism is a leading cause for maternal mortality. Because of the increase risk for thromboembolism in pregnancy and the postpartum period, the clinician must be on high alert for the signs and symptoms and use appropriate diagnostics in a timely manner so that prompt anticoagulation therapy can be initiated. A diagnostic and management approach for both deep vein thrombosis and pulmonary embolism and for prophylaxis against thromboembolism in the obstetric patient are crucial to decreasing morbidity, mortality, and long-term sequelae.

Deep venous thrombosis and pulmonary embolism.

TO THE EDITOR: It is with great interest that we have read the clinical article by Rolston et al.10 (Rolston JD, Han SJ, Bloch O, et al: What clinical factors predict the incidence of deep venous thrombosis and pulmonary embolism in neurosurgical patients? J Neurosurg 121:908–918, October 2014). They have investigated risk factors for venous thromboembolisms (VTEs) in neurosurgical patients using a large data set acquired from the American College of Surgeons’ National Surgical Quality Improvement Program database over a 5-year period.10 In 1.7% of the 38,058 neurosurgical cases they observed, VTE became clinically evident within 30 days after surgery. Due to the apparent risks of intracranial hemorrhages, neurosurgeons are overly cautious in their use of perioperative anticoagulant and/ or antithrombotic agents. Nevertheless, the complications of a VTE, such as deep venous thrombosis or pulmonary embolism, have great impact on outcome in terms of morbidity and mortality. In a recent study we observed 90-day overall mortality rates of 5.0% and 23.1% when deep venous thrombosis and pulmonary embolism, respectively, occurred in patients who had undergone cranial meningioma resection.8 Interestingly, the authors established steroid use as a risk factor for VTE. They suggested this might be due to “a variety of increased procoagulant factors.”10 Indeed, there are some reports corroborating these findings and suggesting that steroids produce a hypercoagulable state in patients.4,11,12 Since the landmark report of Galicich et al. in 1961, high-dose corticosteroids are routinely administered to patients undergoing cranial surgery.7,9 More recently, a renewed interest in the use of corticosteroids for both the medical treatment and perioperative medical treatment of chronic subdural hematoma (CSDH) has been sparked.2,5,6 This usage raises some major questions when considering the potential VTE complications. Several comments on the use of glucocorticoids and the risk of VTE should be made, despite the findings of Rolston et al. First, Rolston et al. could not define, and therefore not investigate, steroid use, because the pathology they investigated is subject to significant variation. Moreover, there is no information on dose and duration of treatment. Second, to date, there is only one extensive review of literature by van Zaane et al. that attempts to shed light on this topic.13 However, the findings therein are tempered, as the authors state, by the lack of high-quality randomized trials. Nevertheless, they have shown that glucocorticoids tend both to lower the levels of several procoagulant factors, such as von Willebrand factor and fibrinogen, and simultaneously to give rise to an impaired fibrinolytic activity through increasing the levels of plasminogen activator inhibitor–1 (PAI-1). Thus, the net result of these mechanistic actions of corticosteroids on the coagulation system is not necessarily prothrombotic, or at least not adding to the thrombotic risk imposed by the surgery itself.13 Third, in a previous study,3 we observed that in patients who underwent surgery for CSDH, and who were concomitantly treated with high-dose glucocorticoids, the incidence of VTE was 1.8%, which supports the findings of Rolston et al.10 In these patients, we have found that both VTE and mortality were in fact not related to the duration of high-dose corticosteroid use. On the contrary, in patients operated on for intracranial meningiomas, all treated with perioperative corticosteroids, the occurrence of VTE was 7.2%.8 This difference in VTE occurrence between these two conditions, with the same corticosteroid regimen, probably reflects the patient’s hypercoagulable state in tumor surgery and thus underlines the importance of the pathology at hand rather than corticosteroid administration itself.1,8 Considering the above, we believe that further research is needed to assess the risk-benefit ratio of glucocorticoid use in neurosurgical practice, which requires a well-designed randomized controlled trial and clinical outcome studies. Additionally, we strongly suggest that VTE complications should be assessed as a major outcome, related to mortality and quality of life, in such studies to assess the effects of glucocorticoid treatment in a doseand timedependent manner.