Prospective Trial of a Novel Nomogram to Achieve Updated Vancomycin Trough Concentrations

Abstract

Purpose. To determine if the use of a novel vancomycin nomogram predicts dosing regimens that achieve target trough concentrations equal to or more accurate than dosing regimens calculated using traditional pharmacokinetic calculations, evaluate the incidence of subtherapeutic and supratherapeutic troughs, and assess pharmacist's impressions of the nomogram. Methods. Prospective, open-label study in 473 patients who had a new order for vancomycin and were >18 years of age and ≤120 kg. Patients were randomized to the active group, dosed using the nomogram, or to the control group, dosed using traditional pharmacokinetic calculations already in place at our institution. Results. Patients dosed via nomogram were within the appropriate trough range in 44% of cases compared to 33% in the control group (P = 0.014). Vancomycin troughs less than 10 mcg/mL were significantly decreased with the use of nomogram (P = 0.032). Incidence of supratherapeutic troughs, greater than 20 mcg/mL, was not significantly different between groups (P = 0.706), and pharmacists agreed that the nomogram was easy to use and saved their time. Conclusions. A novel vancomycin nomogram was prospectively validated and found to be more effective than traditional pharmacokinetic dosing. The nomogram is being implemented as the standard dosing protocol at our institution.

Problemos Gydant Vankomicinu Kritinių Būklių Pacientus

“…Autoriai aiškina, kad skiriant vankomiciną injekcijomis ir sekant jo koncentraciją, reikalinga didesnė vaisto dozė, norint pasiekti terapinę koncentraciją plazmoje, nei taikant nepertraukiamą infuzinę terapiją [22]. Nors ir atlikta nemažai tyrimų, siekiant nustatyti, kaip tinkamai dozuoti vankomiciną, vieningų rekomendacijų nėra iki šiol [8,23] …”

Evaluation of the Effectiveness of a Vancomycin Nomogram at Predicting Trough Levels within a Therapeutic Range

“…Trough Levels within a Therapeutic Range 714 mg/L to avoid development of resistance, and ideally between 15 mg/L and 20 mg/L for complicated infections such as osteomyelitis, endocarditis, meningitis, bacteremia, and hospital-acquired pneumonia caused by S. aureus to improve penetration, increase probability of obtaining optimal target serum concentrations, decrease the incidence of nephrotoxicity, and improve clinical outcomes [8,9] 1.2g q12h 1g q8h 1g q8h 1.2g q8h 1.2g q8h 1g q6h 100 1.2g q24h 1.2g q18h 1g q12h 1g q12h 1.2g q12h 1g q8h 1g q8h 1.2g q8h 1g q6h 1g q6h 105 1g q18h…”

“…More recently, several studies have discerned worse clinical outcomes for patients infected by MRSA isolates with a vancomycin MIC ≥ 1 mg/L [5][6][7][8][9]. The pharmacokinetic parameter that best predicts the efficacy of vancomycin is the area under the curve (AUC) to MIC ratio (AUC:MIC) [6,8,9]. Specifically, studies have shown that an AUC:MIC ≥ 400 is associated with clinical success of vancomycin therapy [6,8,9].…”

“…The pharmacokinetic parameter that best predicts the efficacy of vancomycin is the area under the curve (AUC) to MIC ratio (AUC:MIC) [6,8,9]. Specifically, studies have shown that an AUC:MIC ≥ 400 is associated with clinical success of vancomycin therapy [6,8,9].…”

“…Therefore, vancomycin serum trough concentrations are used as the conventional method for monitoring vancomycin effectiveness [5,8,9]. To obtain the most accurate results, trough concentrations should be drawn just prior to the next dose once the patient has reached steady-state [8].…”