title: No influence of large volume blood loss on serum vancomycin concentrations during orthopedic procedures.
abstract: We prospectively studied orthopedic patients with either large or small blood loss who also received vancomycin prophylaxis to determine the effect of intraoperative volume shifts on serum vancomycin concentrations. There were 6 index patients in the large blood loss group (greater than 2 L), and 7 in the control group (less than 2 L). Mean estimated blood loss for index and controls was 4.4 L and 1.0 L, respectively. Mean intraoperative fluid resuscitation, excluding blood products, was 12.4 L and 5.1 L, respectively. There was a modest inverse correlation between blood loss and intraoperative serum half-life of vancomycin. Although controls maintained slightly higher intraoperative vancomycin concentrations at each time-point, there was no statistically significant difference between the groups with regard to absolute concentrations or rate of decline. After 8 hours, the serum vancomycin concentration exceeded the MIC-90 for Staphylococcus aureus by approximately eightfold in all but one case patient. This was a morbidly obese patient with massive blood loss. Thus, blood loss during orthopedic procedures has minimal effects on intraoperative kinetics of vancomycin. Redosing is rarely indicated, although a preoperative 1.5 gram-dose should be considered for patients weighing more than 90 kg.
authors: Department of Orthopaedics, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
authors: J W
authors: JW
authors: Klekamp
authors: D
authors: D
authors: DiPersio
authors: D W
authors: DW
authors: Haas
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000097:blood* / Q000493:pharmacokinetics / Q000627:therapeutic use; D019072:Antibiotic Prophylaxis; D016063:Blood Loss, Surgical / Q000706:statistics & numerical data*; D001810:Blood Volume; D001835:Body Weight; D016903:Drug Monitoring; D005440:Fluid Therapy / Q000379:methods; D006801:Humans; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D019637:Orthopedic Procedures / Q000009:adverse effects; D011446:Prospective Studies; D012151:Resuscitation / Q000379:methods; D013997:Time Factors; D014640:Vancomycin / Q000097:blood* / Q000493:pharmacokinetics / Q000627:therapeutic use
chemical_list: D000900:Anti-Bacterial Agents; D014640:Vancomycin