OTA 2006 Posters
Scientific Poster #94 Basic Science
Pilot Study Evaluating the Efficacy of Reamer/Irrigator/Aspirator (RIA)
for Attenuating Polymorphonuclear Priming following Intramedullary Nailing
of Femoral Fractures
Steven J. Morgan, MD; Anand A. Parekh, MRCS (Eng);
Wade R. Smith, MD; Allison E. Williams, ND, PhD; Juan F. Agudelo, MD; Ruth
M. Grosskreuz, MD; Phillip C. Eckels, BA; Ernest E Moore, MD
(all authors: a-AO Research Foundation)
Department of Orthopaedics and Department of General Surgery, Denver Health
Medical Center, University of Colorado School of Medicine,
Denver, Colorado, USA
Purpose: Polymorphonuclear leukocyte (PMN) priming is related to
the postinjury inflammatory response in trauma. Intramedullary (IM) reaming
causes systemic release of IM contents, a cause of PMN priming. The RIA
(Synthes, Paoli, PA) is a flexible, single-pass reamer irrigator and aspirator
system designed to reduce the amount of embolic debris. Our purpose was
to investigate whether the RIA attenuates postoperative PMN priming compared
to a standard reamer following reamed IM nailing of isolated femoral fractures.
Methods: A prospective, randomized protocol was implemented. Inclusion
criteria were: unilateral femur fracture requiring intramedullary nailing,
age >18, and Injury Severity Score (ISS) <25. Patients were randomized
to a standard reamer or the RIA. Blood was obtained and processed at 4 time
points: 0 (prior to reaming), 6, 12, and 24 hours. Neutrophil activation
markers (CD11b, CD62L and CD66b) were analyzed using flow cytometry and
a repeated measures analysis of variance was performed. SPSS 11.5 was used
for statistical analysis.
Results: 21 patients were enrolled in the study. Only 16 patients
had valid antibody data. The mean age was 33 years. The average ISS was
12 (range, 9-25). There were no statistically significant differences in
the antibody levels between the reamer groups (P >0.05). Statistically
significant differences were found across time for CD11b between the mean
0 and 12 hour measurements (4.295, 3.936, P <0.01), and the mean
0 and 24-hour measurements (4.295, 5.467, P <0.01). No statistically
significant differences were found across time points in the CD62L or CD66b
levels (P >0.05). There was a statistically significant interaction
between time and reamer group for the CD62L marker. The CD62L levels in
the RIA group were higher than the standard reamer group at the 0 and 6-hour
measurements, and lower at the 12- and 24-hour measurements. Systemic complications
included one case of acute respiratory distress syndrome in the RIA group.
Conclusions/Significance: No differences were found in PMN priming
markers between the reamer groups. Our preliminary results suggest that
the RIA system does not attenuate PMN priming in a unilateral femur fracture
model, but that time may be a critical factor. Further research is needed
to determine the effect of time on neutrophil priming in trauma patients,
and whether the effect of reamer type may be more pronounced in polytrauma
patients.
If noted, the author indicates something of value received.
The codes are identified as a-research or institutional support; b-miscellaneous
funding; c-royalties; d-stock options; e-consultant or employee; n-no conflicts
disclosed, and *disclosure not available at time of printing.
·
The FDA has not cleared this drug and/or medical device for the use
described in this presentation (i.e., the drug or medical device is being
discussed for an "off label" use). · · FDA
information not available at time of printing.