Skeletal Muscle and Adipose Tissue Study

Study Overview
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Brief Summary
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The purpose of this research study is to compare the current standard of care for prophylactic Cefazolin administered every 3 hours intravenously with continuous infusion of Cefazolin during pediatric spinal surgery.

Detailed Description
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Determine the skeletal muscle and adipose tissue disposition of prophylactic Cefazolin using microdialysis sampling in a cohort of patients diagnosed with idiopathic scoliosis undergoing posterior spinal fusion (PSF) for administration of Cefazolin by either continuous infusion or intermittent bolus.

Official Title
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Skeletal Muscle and Adipose Tissue Concentrations of Cefazolin Comparing Two Different Dosing Regimens During Pediatric Posterior Spinal Fusion Surgery

Conditions
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Idiopathic Scoliosis

Intervention / Treatment
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* Drug: Bolus dose of Cefazolin
* Drug: Continuous Cefazolin drip
* Device: Paraspinal muscle microdialysis catheters
* Device: Subcutaneous microdialysis catheters


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosis of idiopathic scoliosis Planned posterior spinal fusion surgery (PSFS) Age: 12-20 years old American Society of Anesthesiology status I or II undergoing posterior spinal fusion for at least 6 levels No known allergy to cefazolin Exclusion Criteria: Known allergy to cefazolin Anatomical or other abnormalities that precluded insertion of a microdialysis catheter into the selected paraspinal muscle Known renal or hepatic insufficiency or failure

Ages Eligible for Study
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Minimum Age: 12 Years
Maximum Age: 20 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Simple randomization will be used with each patient has probability 0.5 to be assigned in Group I or Group II. Computer program will generate a uniform random variable between 0 to 1, with subject assigned to Group I if the value is less than 0.5 and assigned to Group II if the value is greater than 0.5.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: First Regimen Group<br>The first regimen will consist of a bolus dose of Cefazolin 30mg/kg up to a maximum of 2000mg IV administered prior to surgical incision. The same pre-operative dose of Cefazolin will be repeated every 3 hours until the completion of surgery. Two will paraspinal muscle microdialysis catheters and two subcutaneous microdialysis catheters will be inserted. | Drug: Bolus dose of Cefazolin<br>* Mode of Cefazolin administration will be a intermittent bolus<br>* Other names: Standard mode of prophylactic cefazolin administration;Device: Paraspinal muscle microdialysis catheters<br>* Two dialysis probes will be inserted into a paraspinal muscle<br>* Other names: Paraspinal muscle dialysate sample;Device: Subcutaneous microdialysis catheters<br>* Two dialysis probes will be inserted into a paraspinal subcutaneous region<br>* Other names: Subcutaneous dialysate sample;|
| Active Comparator: Second Regimen Group<br>The second regimen will consist of an initial bolus dose of 30 mg/kg up to maximum of 2000 mg. Following the initial bolus dose a continuous Cefazolin drip will start until the end of surgery. Cefazolin drip dose will be 10 mg/(kg*h) up to maximum of 667 mg/h.Two microdialysis catheters will be inserted into a paraspinal muscle and two microdialysis catheters will be inserted subcutaneously. | Drug: Continuous Cefazolin drip<br>* Mode of Cefazolin administration will be a continuous drip<br>* Other names: Continuous infusion of prophylactic cefazolin;Device: Paraspinal muscle microdialysis catheters<br>* Two dialysis probes will be inserted into a paraspinal muscle<br>* Other names: Paraspinal muscle dialysate sample;Device: Subcutaneous microdialysis catheters<br>* Two dialysis probes will be inserted into a paraspinal subcutaneous region<br>* Other names: Subcutaneous dialysate sample;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Unbound Cefazolin Concentration in Skeletal Muscle | First regimen and second regimen difference between unbound Cefazolin concentrations in the interstitial fluid of skeletal muscle | Changes from baseline (pre-op) up to end of surgical procedure | 
| Unbound Cefazolin in Adipose Tissue | First regimen and second regimen difference between unbound Cefazolin concentrations in the interstitial fluid of adipose tissue | Changes from baseline (pre-op) up to end of surgical procedure | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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tissue microdialysis, spinal fusion, surgical site infection