Introduction: Deep vein thrombosis (DVT) is a major focus of patient safety indicators and a common cause of morbidity and mortality. Many practices, including our own, use screening ultrasonography to reduce poor outcomes. However, its role in reducing pulmonary emboli (PE) and mortality is unclear. A recent hospital policy change provided the opportunity to compare independent groups: patients treated under a prior paradigm of weekly screening ultrasonography versus a post-policy change group where weekly surveillance was no longer performed.
Methods: 1934 consecutive patients were reviewed, with a two-month washout period around the policy change. Criteria for inclusion were admission to the neurosurgical service or consultation for > 72 hours and hospitalization for > 72 hours. Primary outcomes examined were the rate of PE diagnosis, all-cause mortality at discharge and 30 days, DVT diagnosis rate, and IVC filter rate. Power analysis demonstrated a 91% power to detect an absolute difference of 5% in PE rate, with an alpha of 0.05. A p value < 0.05 was considered significant.
Results: Of the 1934 reviewed patients, 520 met criteria for the pre-group and 275 for the post-group. All data are presented as pre versus post. There was no difference in the PE rate (1.9% versus 1.5%; p = 0.63) nor mortality at discharge (6.6% versus 3.6%; p = 0.08) and at 30 days (6.8% versus 4.4%; p = 0.16). There were significant differences in DVT rate (12.3% versus 3.6%; p < 0.01) and IVC filter rate (6.5% versus 2.2%; p = 0.01).
Conclusions: Based on these data, there does not appear to be an identifiable benefit to screening patients. While the pre-group had significantly higher rates of DVT diagnosis and IVC filter placement, the screening, additional diagnosis, and subsequent interventions did not appear to improve patient outcomes. Ultimately, this makes screening difficult to justify.
Patient Care: Deep vein thrombosis (DVT) is a common cause of preventable mortality and morbidity in patients hospitalized for surgery due to their implication in up to 90% of pulmonary emboli. While sequential compression devices (SCDs), early ambulation, and pharmacologic anticoagulation are standard of care for neurosurgery patients, the role of screening ultrasonography is less clear. Determining whether the use of screening ultrasonography is an effective way to decrease morbidity and mortality, or if they simply increase healthcare consumption, would benefit overall patient care.
Learning Objectives: By the conclusion of this session, participants should be able to 1) describe the importance of evaluating the role of screening ultrasonography in reducing the PE rate and mortality in hospitalized neurosurgical patients, 2) discuss, in small groups, prophylactic techniques and protocols used to best prevent and screen for deep vein thrombosis while minimizing cost and maximizing benefit, and 3) identify an effective protocol for DVT screening and/or prophylaxis that works toward reducing PE rates and mortality in hospitalized neurosurgical patients.