Pharmacokinetics of topical and intravenous cefazolin in patients with clean surgical wounds.

BACKGROUND: Surgical-site infection is a common postoperative nosocomial infection. Surgeons frequently treat operative patients with protective antibiotics and often choose cefazolin as the drug. Treatment schemes include both preoperative intravenous dosing and intraoperative dosing by irrigation. This study was designed to measure cefazolin concentrations both in serum and in wound drain fluid after intravenous dosing and after irrigation. METHODS: The authors conducted an institutional review board-approved study involving randomized allocation of breast reduction patients to group 1 (preoperative intravenous dosing) or group 2 (intraoperative dosing by irrigation). Each patient had serum and wound drainage specimens measured over time for cefazolin concentrations. Cefazolin dosing was based on preparations commonly used in the authors' hospital. Results from 24 patients are reported. RESULTS: Patients treated by conventional preoperative intravenous dosing displayed the expected serum degradation curve. These patients also demonstrated wound drainage concentrations (peak, 22.49 microg/ml) for approximately 4 to 5 hours. Measured concentrations were above the minimum therapeutic concentration (8 microg/ml) for Staphylococcus aureus. Patients treated by wound irrigation also demonstrated serum concentrations above minimum therapeutic concentration. In addition, these patients' wound drain fluid demonstrated very high cefazolin concentrations (peak, 4185.93 microg/ml), which remained high for 24 hours. CONCLUSIONS: Protective cefazolin concentrations in the wound can be achieved by both intravenous and irrigation delivery. Wound irrigation produces higher concentrations for longer periods of time.

Vacuum-assisted closure for defects of the abdominal wall.

BACKGROUND: Reconstruction of the abdominal wall poses a problem common to many surgical specialties. Abdominal wall defects may be caused by trauma and/or prior surgery, with dehiscence or infection. Several options to repair the structural integrity of the abdominal wall exist, including primary closure, flaps, mesh, and skin grafts. Complications of these procedures include recurrent infection of the abdominal wall, infection of mesh, dehiscence, flap death, and poor skin graft take. Risk factors predisposing to these complications include tissue edema, preoperative tissue infection, and patient debilitation, with poor wound healing potential. Ideally, reconstruction should be performed on a nonedematous, clean tissue bed with bacterial levels less than 10 bacteria/cm in a well-nourished patient. METHODS: Vacuum-assisted closure was used in a series of patients in an attempt to prepare the abdominal wall for reconstruction and reduce the risk of complications. Charts were reviewed for 100 patients who underwent abdominal wall reconstruction after vacuum-assisted closure therapy. Their wound cause, reconstruction technique, complications, and number of days on the vacuum-assisted closure device are reported. RESULTS: The ability of vacuum-assisted closure to reduce edema, increase blood flow, potentially decrease bacterial colonization, and reduce wound size greatly facilitated abdominal wall reconstruction. The vacuum-assisted closure device served as a temporary dressing with which to control dehiscence and to maintain abdominal wall integrity when bowel wall edema prevented abdominal closure. CONCLUSION: Vacuum-assisted closure therapy frequently shortened time to abdominal wall reconstruction and simplified the method of reconstruction.