Background: Procalcitonin (PCT) has been used as marker of infection, a guide to antibiotic therapy and a measure of response to antibiotic treatment. Since PCT is elevated by the inflammatory response, levels are also elevated following significant surgical or traumatic stress, making its use as a surrogate for infection problematic in these populations. We hypothesized that interval surgical stress following trauma would result in elevations PCT, confounding its use as a marker of infection.

Our aim is too characterize PCT levels in multiple injured trauma patients undergoing orthopedic procedures and assess its value in predicting infection.

Methods: A random selection of patients admitted to the Trauma intensive care unit underwent orthopedic procedures including intramedullary (IM) nailing of long bones and open reduction internal fixation (ORIF) of various fractures. In addition to daily WBC and CRP, daily PCT levels were obtained over a seven day period. PCT was measured on the Brahms Kryptor. Daily maximal temperature (Tmax), and heart rate (HRmax) were also collected. These markers of inflammation were retrospectively correlated with the diagnosis of infection, and the performance of surgical procedures.

Non-normally distributed variables were reported by calculating the median and IQR for each patient and then for the population (infected vs. non-infected) and analysis was conducted using Wilcoxon-rank sum test. Normally distributed variables were reported by mean and standard deviation and differences in the populations analyzed with two sample t-test.

Results: Eighteen patients underwent orthopedic procedures during the seven day course. Seven patients developed infections during the study period: 5 pneumonias, 1 pelvic infection, and 1 gastrostomy tube leak.

Out of all the variables compared in this trauma population, only median PCT was statistically significantly different between these two populations (p=0.0098). Markers usually accepted as denoting signs of infection or inflammation: Tmax (p=0.2198), WBC (p=0.6180), CRP (p=0.1573), and HRmax (p=0.6011) did not show a statistically significant difference between the two populations.

Conclusion: In this small population of Trauma patients undergoing orthopedic procedures, preliminary results suggest that PCT may be useful in distinguishing between infected and non-infected patients, while frequently used markers for infection and inflammation such as WBC, CRP, and Tmax were not. A larger, prospective study is needed to confirm these findings.