cefamandole and Aortic-Aneurysm

The pharmacokinetics of prophylactic antibodies may differ in cardiac and aortic aneurysm surgery for at least two reasons: aortic aneurysm surgery generally entails a greater blood volume loss and replacement, and aortic aneurysm surgery usually does not require extracorporeal cardiopulmonary bypass. We prospectively studied two different cefamandole dosing regimens in patients undergoing aortic aneurysm surgery (phase 1, 1 gm intravenously at the induction of anesthesia; phase 2, 2 gm intravenously at the induction of anesthesia followed by 1 gm intravenously every 2 hours during surgery). In phase 1 and 2 plasma levels were measured at the time of skin incision, aortic cross-clamping, aortic unclamping, and skin closure. In phase 2 cefamandole elimination in urine and cell-saver effluent was also determined. An adequate plasma level of 10 micrograms/ml was maintained in only 4 of 14 patients in phase 1, but in 10 of 10 patients in phase 2. Cefamandole loss in cell-saver effluent was 136 +/- 100 mg, which was 13% of the measured renally excreted amount. As has been previously shown in cardiac surgery, a cefamandole prophylactic antibiotic regimen of 2 gm intravenously at the induction of anesthesia followed by 1 gm every 2 hours during surgery provides a dependable and practical dosing regimen in patients undergoing aortic aneurysm surgery.

Topics: Aged; Aorta, Abdominal; Aorta, Thoracic; Aortic Aneurysm; Cefamandole; Drug Administration Schedule; Female; Humans; Male; Middle Aged; Premedication; Prospective Studies; Reproducibility of Results

Prophylactic antibiotics significantly decrease the incidence of infection in various surgical procedures. Although antibiotics must be administered preoperatively to be effective, it is unknown whether therapeutic concentrations are necessary throughout the operation to prevent infection. Furthermore, the pharmacokinetics of antibiotics during surgical procedures is not well understood. Several factors, including blood loss, fluid redistribution, and changes in renal blood flow may alter the pharmacokinetic disposition of the antibiotic. In a controlled investigation of intraoperative antibiotic pharmacokinetics, cefamandole was studied in eight patients undergoing elective surgery of the abdominal aorta and peripheral vasculature. Both elimination half-life (67 +/- 19 minutes versus 93 +/- 23 minutes) and the volume of distribution (16.8 +/- 5.3 liters versus 25.2 +/- 11.9 liters) increased when compared with the preoperative state. The increased volume may be due, in part, to redistribution of fluid. Plasma concentrations of antibiotic were low at the time of graft placement in those patients with normal renal function. Additional antibiotic dosing may be warranted prior to prosthesis insertion in these patients.

Topics: Aorta, Abdominal; Aortic Aneurysm; Blood Vessel Prosthesis; Cefamandole; Female; Femoral Artery; Half-Life; Humans; Intraoperative Period; Male; Middle Aged; Premedication; Vascular Surgical Procedures

Topics: Adult; Aged; Anti-Bacterial Agents; Aortic Aneurysm; Arterial Occlusive Diseases; Cefamandole; Drug Therapy, Combination; Female; Floxacillin; Humans; Leg; Male; Middle Aged; Premedication; Surgical Wound Infection