K. Treto1, A. Giancarelli1, K. Safcsak1, B. Hobbs1, M. Cheatham1, I. Bhullar1 1Orlando Regional Medical Center,Department Of Surgical Education,Orlando, FL, USA
Introduction:
~~The current guidelines from the American College of Chest Physicians (ACCP) from 2008 recommend one standard dose of chemical prophylaxis (CP) for all trauma patients regardless of weight and Body Mass Index (BMI). The utility of weight-adjusted CP for obese patients remains controversial. Earlier initiation of CP (within 24 hours of admission) may also decrease pulmonary embolism (PE) rate. The purpose of this study was to evaluate the effect of BMI and timing of CP on PE rate in patients receiving standard chemical and mechanical prophylaxis after traumatic injury.
Methods:
~~The records of adult patients admitted to the trauma team from 2013-2015 were retrospectively reviewed. Regarless of BMI, standard practice at our institution was to provide one dose of enoxaparin 30 mg SQ every 12 hours for all trauma patients without contraindications to anticoagulation. Traumatic brain injury patients received 5000 units of SQ Heparin every 8 hours instead of enoxaparin (neurosurgery preference). The timing of CP initiation, however, was not standard and varied during the above study period. Patients that did not receive any chemical prophylaxis were excluded. Patients were divided into three groups based on admission BMI, Ideal weight [IW] [BMI<25], Over weight [OW] [BMI 25-29.9], and Obese [OB] [BMI>30]. PE rates were compared based on weight (IW vs. OW), and (IW vs. OB) and timing of CP (≤24 hours after admission [Early] vs. >24 hours after admission [Late]). Statistical analysis was performed using mean, Fisher’s exact test, and Student’s t-test.
Results:
~~2178 patients were identified that met the above criteria. There were 899 IW, 730 OW, and 549 OB patients. Compared to the IW the OW and OB groups both had a significantly higher PE rate (IW vs. OW, 0.2% vs 0.8%, p=0.04), (IW vs. OB, 0.2% vs 1.6%, p=0.004). There was also a trend toward significance for patients that had earlier CP initiation (≤24 hours vs. >24 hours, 0.3 vs. 1.0, p=0.07). The PE rate was then evaluated as a function of both BMI and time (Fig 1). As BMI increases the PE rate shifts upward to a higher frequency curve over time. The OB group had the highest PE rate at each time period. The curves show clear separation with no overlap for PE rate with OB>OW>IW. The highest PE rate occurred in the first ten days after admission for all three groups.
Conclusion:
~~After traumatic injuries, despite standard mechanical and CP, OB and OW patients had a significantly higher PE rate than IW patients. Weight adjusted CP may need to be re-evaluated as a possible means of decreasing this complication. Early initiation of CP (<24 hours after admission) may also play a role in decreasing PE.
