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The pharmacokinetics of Simplex-tobramycin bone cement
G J Sterling1, S Crawford, J H Potter
1Department of Orthopaedic Surgery, Prince Charles Hospital, Chermside, Queensland, Australia.
The Journal of Bone and Joint Surgery. British Volume
|August 2, 2003
Summary
Simplex-tobramycin bone cement provides excellent local antibiotic delivery after total hip replacement (THR). This study found high tobramycin levels in drainage fluid with minimal systemic absorption, confirming its safety and efficiency.
Area of Science:
- Orthopedic Surgery
- Pharmacology
- Biomaterials Science
Background:
- Total hip replacement (THR) is a common procedure for osteoarthritis.
- Antibiotic-loaded bone cement is used to prevent infection.
- Understanding antibiotic elution is crucial for optimizing treatment.
Purpose of the Study:
- To determine the elution characteristics of Simplex-tobramycin bone cement.
- To assess tobramycin concentrations in drainage fluid, serum, and urine post-THR.
- To evaluate the safety and efficacy of this antibiotic delivery method.
Main Methods:
- Prospective investigation of ten patients undergoing cemented primary THR.
- Collection of blood, urine, and drainage fluid specimens for 72 hours postoperatively.
- Quantification of tobramycin concentrations using specified analytical methods.
Main Results:
- High tobramycin concentrations were observed in drainage fluid, peaking at 103 mg/l at 1 hour.
- Mean serum tobramycin levels peaked at 0.94 mg/l at 3 hours, declining rapidly.
- Urinary tobramycin levels peaked at 57.8 mg/l at 12 hours.
- A direct correlation was found between implanted cement amount and systemic absorption.
- Excellent local delivery with minimal systemic concentrations was achieved.
Conclusions:
- Simplex-tobramycin bone cement demonstrates efficient local antibiotic delivery.
- The cement is a safe method for antibiotic administration following total hip replacement.
- Minimal systemic absorption suggests a favorable safety profile.
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