Study of Repeated Cefoxitin Administration in Major Abdominal Surgery Using a Microdialysis Technique

Study Overview
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Brief Summary
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The surgical site infection is one of the most important causes of postoperative morbidity. The appropriate antibiotic prophylaxis is one of the most effective ways to prevent surgical site infections. The recommendations of the French Society of Anesthesia Resuscitation on antibiotic prophylaxis in long surgeries are based on low documentation, including frequency and dosage of reinjection. The main objective of the study is to describe the tissue and plasma pharmacokinetics of cefoxitin after repeated injections. This is an open monocentric study (phase 4) including adults aged 18 to 80 years in need of major abdominal surgery whose foreseeable time exceeds 4 hours and justifying an antibiotic prophylaxis by cefoxitin. They receive 2 g cefoxitin parenterally at least 30 minutes before the incision and then every 2 hours until closing. The primary endpoints are: Total and plasma free concentrations of cefoxitin 0, 10, 30, 60, 90, 120 minutes after start of each infusion cefoxitin Tissue free concentrations of cefoxitin every 20 minutes after the start of the first infusion cefoxitin until skin closure Urinary concentrations of cefoxitin

Conditions
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Antibiotic Prophylaxis Surgery

Intervention / Treatment
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* Drug: cefoxitin


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients who underwent major abdominal surgery whose forseeable time exceeds 4 hours and requires an antibiotic prophylaxis by cefoxitin Exclusion Criteria: morbid obesity (BMI > 35 kg/m²) severe renal impairment (clearance creatinine < 30ml/min) beta lactam hypersensitivity pregnancy

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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: Other
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Intervention/Treatment |
| --- |
|Drug: cefoxitin|Parenteral administration of 2g of cefoxitin at least 30 minutes before incision and then every 2 hours until closing|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Total and free plasma of cefoxitin after repeated injections |  | 48 hours | 
| Free tissue concentration of cefoxitin every 20 minutes after the beginning of injections |  | 48 hours | 
| Concentration of cefoxitin in urine after every injection |  | 48 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of time when tissue concentration of cefoxitin is higher than the minimal inhibitory concentration of target organisms |  | 48 hours | 
| Concentrations of antibiotic in peritoneal fluid |  | 48 hours | 
| Clearance of distribution of cefoxitin |  | 48 hours | 
| Clearance of elimination of cefoxitin |  | 48 hours | 
| Cmax of Cefoxitin |  | 48 hours | 
| Vd of distribution o cefoxitin |  | 48 hours | 
| Area under the curve of plasma and tissue concentration of cefoxitin |  | 48 hours |