Do stop orders for indwelling urinary catheters reduce the duration of inappropriate urinary catheterization and incidence of urinary tract infection?
Background: About 25% of hospitalized patients have an indwelling urinary catheter inserted, and in 30% to 50% of these patients, urinary catheters are not indicated. Approximately 50% of patients with a catheter inserted for five days or more will develop bacteriuria with about 80% of hospital-acquired urinary tract infections occurring in patients with a urinary catheter.
Study design: A randomized controlled study.
Setting: Three tertiary care hospitals in Ontario, Canada.
Synopsis: 692 patients with indwelling urinary catheters admitted to seven general medical units in three tertiary care hospitals from January 2004 to June 2006 were randomized into two groups: 269 in the stop-order group, and 252 in the usual care group. Patients in the stop-order group had fewer days of inappropriate and total urinary catheter used (2.20 days) compared with the usual care group (3.89 days). There was no difference in the incidence of urinary tract infection between both groups.
Study results were limited by several factors, including a lack of control for exposure of participants to antimicrobials, missing urine cultures, and lack of evaluation of the effect of reducing urinary catheter use on mobility and quality of life. The 1.34-day reduction in the duration of catheterization may not be sufficient to significantly reduce bacteriuria.
Bottom line: Consider using stop orders in all patients with indwelling urinary catheters.
Citation: Loeb M, Hunt D, O’Halloran K, et. al. Stop orders to reduce inappropriate urinary catheterization in hospitalized patients: a randomized control trial. J Gen Intern Med 2008;23(6):816-820.
Does interrupting anticoagulation in patients with atrial fibrillation undergoing surgery cause an increased rate of thromboembolism?
Background: There is a known risk of thromboembolism (between 0.5% and 20% annually) in patients with atrial fibrillation. Studies are limited regarding the risk of thromboembolism with holding anticoagulation in the perioperative period for nonvalvular atrial fibrillation. This study attempted to answer this question.
Study design: Prospective cohort.
Setting: Thromboembolism clinic of the Mayo Clinic.
Synopsis: 345 patients with nonvalvular atrial fibrillation whose anticoagulation was perioperatively held were monitored for three months after surgery for thromboembolic events. Warfarin therapy was held for 5.3 days +/- three days before surgery and restarted 1.3 days +/- 3.4 days after surgery. Bridging heparin therapy was used for 204/386 procedures.
Four patients suffered six thromboembolic events; two patients while receiving bridging heparin therapy and two without heparin. The total incidence of thromboembolic events was 1.1%. This is compared with an expected incidence of 0.09% to 2.07% for patients with atrial fibrillation on warfarin. Bleeding complications rates were also low.
The authors recognized a possible selection bias and the fact patients who received bridging heparin therapy were not randomized. Despite these potential flaws, there seems to be minimal risk of holding anticoagulation in the perioperative period. Bridging heparin therapy added no additional benefit.
Bottom line: There is no increased risk of thromboembolism if anticoagulation is interrupted without bridging therapy in nonvalvular atrial fibrillation patients undergoing surgery.
Citation: Wysokinski WE, McBane RD, Daniels PR, et al. Periprocedural anticoagulation management of patients with nonvalvular atrial fibrillation. Mayo Clinic Proceedings 2008;83(6):639-645.
Are obese patients under-dosed when prescribed intravenous vancomycin?
Background: Weight-based vancomycin dosing has been recommended by the Infectious Diseases Society of America, yet flat dosing is still commonly employed. Flat dosing has the potential of increasing resistance and having adverse clinical effects.
Study design: Retrospective cohort.
Setting: Two tertiary care medical centers without pharmacy-guided vancomycin dosing programs.