A. Cipriano1, U. MacBean1, B. Wernick1, R. N. Mubang1, T. R. Wojda1, S. Liu1, S. Bezner-Serres3, D. C. Evans2, B. A. Hoey1, S. Odom3, P. Thomas1, C. H. Cook3, S. P. Stawicki1 1St Luke’s University Health Network,Department Of Surgery,Bethlehem, PA, USA 2Ohio State University,Department Of Surgery,Columbus, OH, USA 3Beth Israel Deaconess Medical Center,Department Of Surgery,Boston, MA, USA
Introduction: Spleen is one of the most commonly injured abdominal organs in blunt trauma. Still, our knowledge of post-injury hematologic parameters is incomplete. This study compares fluctuations of platelet and red blood cell (RBC) indices in patients with splenic injuries who underwent clinical observation (O), embolization (E), or splenectomy (S) during the first 45 post-injury days. We hypothesized that patterns of thrombocytosis, RBC and/or RBC indices (RBCI) vary across the three treatment approaches.
Methods: Following IRB approval at three institutions, a retrospective study of platelet/RBC and RBCI (red blood cell distribution volume – RDW / mean corpuscular volume – MCV) was conducted (Mar 2000 – Dec 2014). We studied patients with admission lengths of >96 hours giving representative samples for each sub-group (O, E, and S). Demographics and injury severity data were abstracted. Composite 7-period moving average graphs of platelet counts and RBC/RBCI from the time of admission to the latest available lab draw (or 45 days maximum) were constructed. Non-parametric statistical testing for any corresponding differences was then performed.
Results: Multiple data points (n=1,110) from 75 patients (25 S, 29 E, 32 O) were analyzed for each study parameter. Median age was 41 years with median ISS 22 (21 for S, 19 for E, 22 for O, p=n/s), median GCS 15, 67% male. Median splenic injury grade followed interventional modality (grade 4 for S, 3 for E, 2 for O). There were no differences in RBC count for the three groups (p=n/s). In aggregate, RDW was greater following S (14.9%) than E (14.3%) or O (13.5%, p<0.01) with the three converging by day 45. Despite temporal variability, MCV was highest for the "observation" group (92.3 vs 91.1 in E and 90.6 in S, p<0.01). For platelets, there were no differences between composite values for S (mean, 378.8) and E (350.1), with both being greater than the O group (272.3, p<0.01) between 15-41 days. Prior to day 15, all groups had similar platelet counts; after day 41, the O and E groups converged at levels approximating 50% of the S group.
Conclusion: This study describes important trends and patterns in RBC, RBCI, and platelets following splenic injuries managed with S, E, or O. Although no differences were noted in RBC counts between therapies, RDW was significantly greater following S than either E or O. MCV displayed significant temporal variability. Finally, platelet counts were similar for both S and E during peak elevations (days 15-41), followed by convergence of E & O groups at normal levels around day 45. Our results provide a foundation for further research in this still poorly explored area, with focus on clinical relevance of observed patterns.
