1. Pre-operative Aspirin Utilization
and the effect on intra-operative
Bleeding in Patients undergoing
Spinal Fusion Surgery
Lucas W. Ashley; Terence Verla, MPH; Jessica
Moreno, RN, BSN; Carlos A Bagley, MD
Duke Spine Center, Duke University, Durham, NC

2. Introduction
• Aspirin (ASA) reduces risk of cardiac, vascular
and cerebral complications in adult patients
• However, it increases the risk of bleeding
• Patients are recommended to temporarily
discontinue ASA use 7-14 days prior to spinal
surgery
• It is not well defined if a history of ASA use
increases intra-operative bleeding or
transfusion requirement

3. Objective
• The purpose of this study was to assess
the effect of pre-operative ASA utilization
on intra-operative blood loss and
transfusion requirement

4. Methods
• Retrospective review of 242 patients that
underwent thoracolumbar surgery
between Jan 1 2008 and December 31
2010.
• Patients were 18 years or older
• Surgery was limited to either degenerative
or idiopathic scoliosis
• Patients were categorized based on pre-
operative ASA utilization

5. Methods (cont.)
• Demographic, clinical and operative data
were obtained form medical records at
Duke University Medical Center
• Estimated blood loss and transfusion
requirement were compared between the
ASA groups

6. Results: Baseline Demographics
Pre-op ASPIRIN No Pre-op ASPIRIN
Total Number 71 171
Age [mean,years] 67.0 years 60.8 years
Gender
Male (%)
Female (%)
31.4%
68.6%
30.8%
69.2%
Race
White (%)
Black (%)
94.3%
4.7%
94.8%
4.2%
Number of Levels Fused
[mean]
5.1 5.82
Hospital Length of stay
[mean, days]
5.25 days 5.31 days

7. Comparison of Operative Blood Loss
P=0.98*
*No significant difference

8. Comparison of Transfusion Requirement
*No significant difference
P=0.99*

9. Conclusion
• The amount of intra-operative blood loss
remains similar, regardless of pre-
operative ASA use
• There was no significant difference in the
transfusion requirement based on ASA
use

10. Future Direction
• Ongoing study by the Duke Spine Center
to evaluate the appropriate time to resume
ASA post-operatively without an increased
risk of bleeding.

11. Works Cited
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Agnelli, Giancarlo, MD, Franco Piovella, MD, Pio Buoncristiani, MD, Paolo Severi,
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12. ACKNOWLEDGEMENT
• Carlos A. Bagley, MD
• Jessica Moreno, RN, BSN
• Terence Verla, MPH
• Duke Spine Center
• Duke University Medical Center
• Dr. Sarah Shoemaker
• NC School of Science and Mathematics
• NCSSM Foundation Board