[The comparison of in vivo and in vitro elution of gentamycin from bone cement].
BACKGROUND
The authors report their in vivo and in vitro results of the elution characteristics of gentamycin sulfate from bone cement, which is the most commonly used way of local antibiotic prophylaxis in Europe in the field of orthopedic surgery.


OBJECTIVE
The aim of this study was to investigate the elution of the gentamycin sulfate from bone cement, describe the dynamics of the emission in time and evaluate the relationship between the minimal inhibitory concentration (MIC) and the eluted concentration of the antibiotic.


METHODS
The in vivo investigation samples were taken from 9 patient from drain fluids to evaluate the eluted antibiotic concentration by fluorescent polarisation immunoassay method (FPI). The in vitro emission-dynamics of two different bone cement-Gentamycin sulphate complex were analysed by plate diffusion method during one-year period after mixing.


RESULTS
Their results showed that 24 hours after the operation the gentamycin concentrations in the drain fluid taken from around the endoprosthesis implanted with Palacos-R bone cement diminished, yet remained above the MIC level. High but rapidly decreasing antibiotic level was detected by the in vitro method within the first week, reading an almost steadily low concentration by the end of the first month. Surprisingly, after one year it was still possible to demonstrate the inhibitory effect of the drug from both tested types of cements.


CONCLUSIONS
It is concluded that the gentamycin is able to elute from the bone cement in useful concentration after the implantation of endoprosthesis. However, this in vitro method is a useful and reproducible technique for the measurement of the efficacy of antibiotic emission from bone cement, the conversation of the results to the in vivo remains to be obscured. Nevertheless, the usage of local antibiotic prophylaxis seems to be useful during orthopaedic major intervention.
Bálint
Lehel
L
Pécsi Tudományegyetem, Orvos- és Egészségtudományi Centrum, Altalános Orvostudományi Kar, Ortopédiai Klinika, Pécs.
Koós
Zoltán
Z
Liszt
Ferenc
F
Kocsis
Béla
B
Farkas
Boglárka
B
Szabó
György
G
D000368:Aged; D000900:Anti-Bacterial Agents / Q000097:blood / Q000378:metabolism* / Q000627:therapeutic use; D019072:Antibiotic Prophylaxis / Q000379:methods; D019644:Arthroplasty, Replacement, Hip / Q000379:methods*; D001843:Bone Cements / Q000378:metabolism*; D004322:Drainage; D005122:Exudates and Transudates / Q000378:metabolism*; D005260:Female; D005839:Gentamicins / Q000097:blood / Q000378:metabolism* / Q000627:therapeutic use; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D008875:Middle Aged; D013997:Time Factors
D000900:Anti-Bacterial Agents; D001843:Bone Cements; D005839:Gentamicins
Gentamicin csontcementbol történo in vivo és in vitro emissziójának összehasonlítása.