title: Antibiotic concentrations in serum and wound fluid after local gentamicin or intravenous dicloxacillin prophylaxis in cardiac surgery.
abstract: One important aim of antibiotic prophylaxis in cardiac surgery is preventing mediastinitis and thus it would appear to be relevant to study the antibiotic concentrations in pericardial/mediastinal fluid. Local administration of gentamicin in the wound before sternal closure is a novel way of antibiotic prophylaxis and could be effective against bacteria resistant to intravenous antibiotics. This study measured dicloxacillin concentrations in 101 patients in serum and wound fluid following intravenous administration of dicloxacillin. Similarly, concentrations of gentamicin in serum and wound fluid were determined in 30 patients after administration of 260 mg gentamicin in the wound at sternal closure. Median dicloxacillin concentrations in serum and wound fluid at sternal closure were 59.4 and 55.35 mg/l, respectively. Gentamicin levels in the wound were very high (median 304 mg/l), whereas serum concentrations were low (peak median 2.05 mg/l). Dicloxacillin, 1 g given intravenously, according to the clinical protocol, resulted in levels in serum and wound fluid at sternal closure likely to prevent Staphylococcus aureus infections. Locally administered gentamicin resulted in high local concentrations, potentially effective against agents normally considered resistant.
authors.affiliation: Department of Cardiothoracic Surgery, Orebro University Hospital, Orebro, Sweden. orjan.friberg@orebroll.se
authors.forename: Orjan
authors.initials: O
authors.lastname: Friberg
authors.forename: Ian
authors.initials: I
authors.lastname: Jones
authors.forename: Lennart
authors.initials: L
authors.lastname: Sjöberg
authors.forename: Bo
authors.initials: B
authors.lastname: Söderquist
authors.forename: Thomas
authors.initials: T
authors.lastname: Vikerfors
authors.forename: Jan
authors.initials: J
authors.lastname: Källman
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019072:Antibiotic Prophylaxis; D001682:Biological Availability; D006348:Cardiac Surgical Procedures / Q000009:adverse effects* / Q000379:methods; D004009:Dicloxacillin / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D005260:Female; D005500:Follow-Up Studies; D005839:Gentamicins / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D006801:Humans; D007262:Infusions, Intravenous; D015552:Injections, Intralesional; D008297:Male; D008480:Mediastinitis / Q000188:drug therapy* / Q000517:prevention & control; D008875:Middle Aged; D011446:Prospective Studies; D018570:Risk Assessment; D013530:Surgical Wound Infection / Q000188:drug therapy* / Q000517:prevention & control; D016896:Treatment Outcome
chemical_list: D005839:Gentamicins; D004009:Dicloxacillin