Abstract
Background
Medical grade Calcium Sulphate can be used as a delivery vehicle for antibiotics. We use these for treating patients with established osteomyelitis, but also use it prophylactic for contaminated war injuries, to fill voids in bone with osteo conductve filler that delivers local antibiotics, and can integrate with bone. Although antibiotic loaded calcium sulphate is increasingly used, there is little data to demonstrate that systemic levels generated by local release of antibiotics are safe. For this reason, we routinely assay systemic levels of antibiotics.
Objectives
To determine if systemic toxicity occurs after the use of antibiotic loaded calcium sulphate in the treatment of bone and soft tissue infection
Material and Method
Bone cavities and soft tissue dead spaces were aggressively debrided, lavaged and packed with Calcium Sulphate (10–40 cc) loaded with Vancomycin (1–4 g) and Gentamicin (240–960 mg). Post-operatively serial assays of Vancomycin and Gentamicin levels 1 hour after surgery then daily for three days. Renal function was also measured
Results
In patients with normal renal function: The systemic levels were either un-measurable at the first assay, or below the acceptable trough level (Mean 2.4 and 1.8 for Vancomycin and Gentamycin respectively). They had measurable systemic levels at the third assay In patients with renal dysfunction: Systemic levels were in the therapeutic range determined for systemically administered antibiotics, but these levels remained high and did not decrease until patients had undergone their routine dialysis.
Conclusions
In patients treated with antibiotic loaded Calcium Sulphate: Antibiotic assays are not necessary in patients who have normal renal function. Patients with impaired renal function should have:
-
Use lower doses of antibiotics
-
Should undergo assays routinely
-
Ensure dialysis after surgery
-
If they remain high, the antibiotic loaded calcium sulphate could be removed
