Surveillance Ultrasound in the Neuro Intensive Care Unit: Time to Deep Vein Thrombosis Diagnosis.

Abstract

Deep vein thrombosis (DVT) and pulmonary embolism (PE) are complications of hospitalization leading to increased morbidity and mortality. Routine surveillance ultrasound has become common practice in some intensive care units (ICU) to detect DVT early and initiate anticoagulation, preventing complications. However, initiating anticoagulants for asymptomatic DVT treatment may increase risk of hemorrhage. The objective of this study was to investigate the value of routine surveillance ultrasound in early DVT diagnosis in Neuro ICU patients. This is a retrospective review of patients diagnosed with DVT during admission to the Neuro ICU at University Hospital from January 1, 2012, through December 31, 2017. Patients were identified through International Classification of Diseases 9th and 10th Revision codes for DVT and PE, screened for inclusion criteria, and then classified as surveillance group or symptom-driven group based on intervention received. Primary outcome was time to DVT diagnosis. Secondary outcome included clinically significant hemorrhage identified by anticoagulation treatment discontinuation for suspected hemorrhage or new or expanding hemorrhage on head computerized tomography (CT). A total of 116 patients were identified, with 50 included: 27 were classified as surveillance and 23 as symptom-driven. Seven patients (surveillance = 3 and symptom-driven = 4) were diagnosed with only PE and were excluded from primary outcome. Median time to DVT diagnosis was similar at 148h for surveillance versus 172h for symptom driven (p = 0.2). There was no difference in treatment discontinuation rates (surveillance 21% vs symptom 31%; p = 0.4). Of the 27 patients with follow-up head CT, two in the surveillance group and two in the symptom-driven group showed a new or expanding hemorrhage. Routine surveillance ultrasound did not lead to significantly earlier DVT diagnosis. Hemorrhagic events were not different between groups. Utility of surveillance ultrasound in this population should be evaluated in large, prospective trials before routine use can be recommended.