Procalcitonin-guided algorithm to reduce length of antibiotic therapy in patients with severe sepsis and septic shock

Background: Procalcitonin (PCT)-protocols to guide antibiotic treatment in severe infections are known to be effective. But less is known about the long-term effects of such protocols on antibiotic consumption under real life conditions. This retrospective study analyses the effects on antibiotic use in patients with severe sepsis and septic shock after implementation of a PCT-protocol. Methods: We conducted a retrospective ICU-database search for adult patients between 2005 and 2009 with sepsis and organ dysfunction who where treated accordingly to a PCT-guided algorithm as follows: Daily measurements of PCT (BRAHMS PCT LIA (R); BRAHMS Aktiengesellschaft, Hennigsdorf, Germany). Antibiotic therapy was discontinued if 1) clinical signs and symptoms of infection improved and PCT decreased to <= 1 ng/ml, or 2) if the PCT value was >1 ng/ml, but had dropped to 25-35% of the initial value within three days. The primary outcome parameters were: antibiotic days on ICU, ICU re-infection rate, 28-day mortality rate, length of stay (LOS) in ICU, mean antibiotic costs (per patient) and ventilation hours. Data from 141 patients were included in our study. Primary outcome parameters were analysed using covariance analyses (ANCOVA) to control for effects by gender, age, SAPS II, APACHE II and effective cost weight. Results: From baseline data of 2005, duration of antibiotic therapy was reduced by an average of 1.0 day per year from 14.3 +/- 1.2 to 9.0 +/- 1.7 days in 2009 (p=0.02). ICU re-infection rate was decreased by yearly 35.1% (95% CI -53 to -8.5; p=0.014) just as ventilation hours by 42 hours per year (95% CI -72.6 to -11.4; p=0.008). ICU-LOS was reduced by 2.7 days per year (p<0.001). Trends towards an average yearly reduction of 28-day mortality by -22.4% (95% CI -44.3 to 8.1; p=0.133) and mean cost for antibiotic therapy/patient by -14.3 Euro (95% CI -55.7 to 27.1) did not reach statistical significance. Conclusions: In a real-life clinical setting, implementation of a PCT-protocol was associated with a reduced duration of antibiotic therapy in septic ICU patients without compromising clinical or economical outcomes.