effect of lenght of surgery on cefoxitine concentration

effect of type of surgery on cefoxitine concentration

These parameters will be calculated according to the initial concentration (C0) and the final concentration (C2) measured at t0 and t2 respectively. A corrective factor will be applied according to the halfway surgery serum concentration of Cefoxitin.

o Clearance: Cl=k x Vd

This parameter will be calculated according to the initial concentration (C0) and the final concentration (C2) measured at t0 and t2 respectively. A corrective factor will be applied according to the halfway surgery serum concentration of Cefoxitin.

o Volume of distribution: D0/C0

This parameter will be calculated according to the initial concentration (C0) and the final concentration (C2) measured at t0 and t2 respectively. A corrective factor will be applied according to the halfway surgery serum concentration of Cefoxitin.

o Half-life: t1/2=ln2/k

This parameter will be calculated according to the initial concentration (C0) and the final concentration (C2) measured at t0 and t2 respectively. A corrective factor will be applied according to the halfway surgery serum concentration of Cefoxitin.

o Area under curve: AUC=C0/k

This parameter will be calculated according to the initial concentration (C0) and the final concentration (C2) measured at t0 and t2 respectively. A corrective factor will be applied according to the halfway surgery serum concentration of Cefoxitin.

o Elimination rate: k=(LnC0-LnC2)/(t2-t0)

o Superficial incisional SSI: at 30 days defined by:

Date of event for infection occurs within 30 days after any operative procedure AND involves only skin and subcutaneous tissue of the incision AND the patient has at least one of the following:

1. purulent drainage from the superficial incision,
2. organisms identified from an aseptically-obtained specimen,
3. from the superficial incision or subcutaneous tissue by a culture or non-culture based microbiologic testing method which is performed for purposes of clinical diagnosis or treatment (e.g., not Active Surveillance Culture/Testing (ASC/AST),
4. superficial incision that is deliberately opened by a surgeon, attending physician or other designee and culture or non-culture based testing is not performed AND patient has at least one of the following signs or symptoms: pain or tenderness;localized swelling; erythema; or heat,
5. diagnosis of a superficial incisional SSI by the surgeon or attending physician or other designee.

Deep incisional SSI at 30 days defined by:

date of event for infection occurs within 30 days after the operative procedure AND involves deep soft tissues of the incision (e.g., fascial and muscle layers) AND patient has at least one of the following:

1. purulent drainage from the deep incision,
2. a deep incision that spontaneously dehisces, or is deliberately opened or aspirated by a surgeon, attending physician or other designee and organism is identified by a culture or non-culture based microbiologic testing method which is performed for purposes of clinical diagnosis or treatment (e.g., not Active Surveillance Culture/Testing (ASC/AST) or culture or non-culture based microbiologic testing method is not performed AND patient has at least one of the following signs or symptoms: fever (>38°C); localized pain or tenderness.
3. an abscess or other evidence of infection involving the deep incision that is detected on gross anatomical or histopathologic exam, or imaging test.

Organ/Space SSI at 30 days defined by:

Date of event for infection occurs within 30 after the operative procedure AND infection involves any part of the body deeper than the fascial/muscle layers, that is opened or manipulated during the operative procedure AND patient has at least one of the following:

1. purulent drainage from a drain that is placed into the organ/space
2. organisms are identified from an fluid or tissue in the organ/space by a culture or non-culture based microbiologic testing method
3. an abscess or other evidence of infection involving the organ/space that is detected on gross anatomical or histopathologic exam, or imaging test evidence suggestive of infection AND meets at least one criterion for a specific organ/space infection site listed: intraabdominal infection, not specified elsewhere including gallbladder, bile ducts, liver, spleen, pancreas, peritoneum, subphrenic or subdiaphragmatic space