scholarly journals Therapeutic Drug Monitoring of Vancomycin: The Relationship Between Trough Plasma Concentration and Creatinine Clearance

2020 ◽  
Vol 1 (2) ◽  
pp. 47-53
Author(s):  
Mohammad Ali Salahshoor ◽  
Masoumeh Kurd ◽  
Abbas Taher ◽  
Sara Ataei ◽  
Omid Heidary Shayesteh ◽  
...  

Background: In this study which was conducted in Besat hospital (Hamadan, Iran), the therapeutic drug monitoring (TDM) of vancomycin (VAN) was carried out based on the quantification of VAN trough in intensive care unit (ICU) patients. Methods: The study population was selected from ICU patients treated by intravenous VAN. To determine VAN trough, blood samples were taken from patients before the fourth dose. Then, trough concentrations were determined by newly developed high-performance liquid chromatography (HPLC) and compared with the conventional method of immunoassay. Twenty patients were included based on the aim of the study. Results: The mean value of the trough for the studied patients was 26.31±18.05 μg/mL. For 16 (80%) patients, trough levels were found to be less than 10 μg/mL. For 12 (60%) patients, creatinine clearance was less than 90 mL/min and more than 120 mL/min. The mean value of creatinine clearance for the studied patients was 95.49± 25.74 mL/min. Based on the results, there was a significant relationship between VAN trough concentration and creatinine clearance (P=0.045). Conclusion: In general, the HPLC method is more sensitive than immunoassay for the determination of VAN in plasma samples. However, VAN dosing based on creatinine clearance is not enough for achieving the goal trough level but measuring the creatinine clearance and trough concentration are considered as vital aspects for the TDM of VAN.

2017 ◽  
Vol 61 (6) ◽  
Author(s):  
Catherine J. Byrne ◽  
Jason A. Roberts ◽  
Brett McWhinney ◽  
Jerome P. Fennell ◽  
Philomena O'Byrne ◽  
...  

ABSTRACT The objective of this study was to explore the following aspects of teicoplanin use in patients with hematological malignancy: early attainment of target trough concentrations with current high-dose teicoplanin regimens, variability in unbound teicoplanin fractions, factors associated with observed total and unbound trough concentrations, efficacy and toxicity, and renal function estimation. This was a single-center, prospective study. Samples for determination of trough concentrations were taken on days 3, 4, 7, and 10. Total and unbound teicoplanin concentrations were determined using validated high-performance liquid chromatography methods. Regression analyses were used to identify the factors associated with the trough concentration. Thirty teicoplanin-treated adults with hematological malignancy were recruited. Despite the use of dosages higher than the conventional dosages, the proportions of patients with a trough concentration of ≥20 mg/liter at 48 h and at 72 h were 16.7% and 37.9%, respectively. Renal function was significantly negatively associated with total trough concentrations at 48 h and 72 h (P < 0.05). For an average hematological malignancy patient (creatinine clearance = 70 ml/min), sequential loading doses of at least 12 mg/kg of body weight may be needed to achieve early adequate exposure. In the absence of measured creatinine clearance, estimates obtained using the Cockcroft-Gault (total body weight) equation could prove to be an acceptable surrogate. The unbound fractions of teicoplanin were highly variable (3.4 to 18.8%). Higher unbound fractions were observed in patients with low serum albumin concentrations. Teicoplanin was well tolerated. Teicoplanin loading doses higher than those in current use appear to be necessary. Increased dosing is needed in patients with increased renal function. The high variability in protein binding supports the contention for therapeutic drug monitoring of unbound teicoplanin concentrations. (This study has been registered with EudraCT under registration no. 2013-004535-72.)


2021 ◽  
Vol 14 (2) ◽  
pp. 119
Author(s):  
Ruben A. G. van Eerden ◽  
Esther Oomen-de Hoop ◽  
Aad Noordam ◽  
Ron H. J. Mathijssen ◽  
Stijn L. W. Koolen

Small molecule kinase inhibitors (SMKIs) are widely used in oncology. Therapeutic drug monitoring (TDM) for SMKIs could reduce underexposure or overexposure. However, logistical issues such as timing of blood withdrawals hamper its implementation into clinical practice. Extrapolating a random concentration to a trough concentration using the elimination half-life could be a simple and easy way to overcome this problem. In our study plasma concentrations observed during 24 h blood sampling were used for extrapolation to trough levels. The objective was to demonstrate that extrapolation of randomly taken blood samples will lead to equivalent estimated trough samples compared to measured Cmin values. In total 2241 blood samples were analyzed. The estimated Ctrough levels of afatinib and sunitinib fulfilled the equivalence criteria if the samples were drawn after Tmax. The calculated Ctrough levels of erlotinib, imatinib and sorafenib met the equivalence criteria if they were taken, respectively, 12 h, 3 h and 10 h after drug intake. For regorafenib extrapolation was not feasible. In conclusion, extrapolation of randomly taken drug concentrations to a trough concentration using the mean elimination half-life is feasible for multiple SMKIs. Therefore, this simple method could positively contribute to the implementation of TDM in oncology.


Critical Care ◽  
2020 ◽  
Vol 24 (1) ◽  
Author(s):  
Dennis Kühn ◽  
Carlos Metz ◽  
Frederik Seiler ◽  
Holger Wehrfritz ◽  
Sophie Roth ◽  
...  

Abstract Background Effective antimicrobial treatment is key to reduce mortality associated with bacterial sepsis in patients on intensive care units (ICUs). Dose adjustments are often necessary to account for pathophysiological changes or renal replacement therapy. Extracorporeal membrane oxygenation (ECMO) is increasingly being used for the treatment of respiratory and/or cardiac failure. However, it remains unclear whether dose adjustments are necessary to avoid subtherapeutic drug levels in septic patients on ECMO support. Here, we aimed to evaluate and comparatively assess serum concentrations of continuously applied antibiotics in intensive care patients being treated with and without ECMO. Methods Between October 2018 and December 2019, we prospectively enrolled patients on a pneumological ICU in southwest Germany who received antibiotic treatment with piperacillin/tazobactam, ceftazidime, meropenem, or linezolid. All antibiotics were applied using continuous infusion, and therapeutic drug monitoring of serum concentrations (expressed as mg/L) was carried out using high-performance liquid chromatography. Target concentrations were defined as fourfold above the minimal inhibitory concentration (MIC) of susceptible bacterial isolates, according to EUCAST breakpoints. Results The final cohort comprised 105 ICU patients, of whom 30 were treated with ECMO. ECMO patients were significantly younger (mean age: 47.7 vs. 61.2 years; p < 0.001), required renal replacement therapy more frequently (53.3% vs. 32.0%; p = 0.048) and had an elevated ICU mortality (60.0% vs. 22.7%; p < 0.001). Data on antibiotic serum concentrations derived from 112 measurements among ECMO and 186 measurements from non-ECMO patients showed significantly lower median serum concentrations for piperacillin (32.3 vs. 52.9; p = 0.029) and standard-dose meropenem (15.0 vs. 17.8; p = 0.020) in the ECMO group. We found high rates of insufficient antibiotic serum concentrations below the pre-specified MIC target among ECMO patients (piperacillin: 48% vs. 13% in non-ECMO; linezolid: 35% vs. 15% in non-ECMO), whereas no such difference was observed for ceftazidime and meropenem. Conclusions ECMO treatment was associated with significantly reduced serum concentrations of specific antibiotics. Future studies are needed to assess the pharmacokinetic characteristics of antibiotics in ICU patients on ECMO support.


2020 ◽  
Vol 14 (Supplement_1) ◽  
pp. S667-S668
Author(s):  
S Gleeson ◽  
K Sugrue ◽  
M Buckley ◽  
J McCarthy

Abstract Background Therapeutic drug monitoring (TDM) is the clinical practice of measuring serum drug concentrations to guide clinical decision making. Achieving therapeutic drug concentrations has been associated with clinical, endoscopic and histological outcomes in IBD. The use of TDM offers a more personalised treatment approach and is associated with sustained clinical remission. Proactive TDM was introduced to the Mercy University Hospital in 2014 for all patients on biologics. Methods One hundred patients receiving biologic infusion (Infliximab) were evaluated post induction (week 12) for therapeutic drug trough concentration and for clinical response. Serum samples were taken from all IBD patients at week 12. Biologic response assessment forms were complete for all patients to assess symptom improvement. Results Thirty-five per cent of patients had sub therapeutic trough levels at week 12. They subsequently received 3 increased doses of 10mgs/kg and levels were rechecked. Of these 90% achieved therapeutic levels after the dose escalation. 65% of patients had therapeutic levels at week 12. There was a correlation between therapeutic trough levels and patient reported improvement of clinical symptoms in 85% of respondents. Conclusion TDM in our unit facilitates appropriate dose 100 patients receiving biologic infusion (Infliximab) were evaluated post induction (week 12) for therapeutic drug trough concentration and for clinical response. Serum samples were taken from all IBD patients at week 12. Biologic response assessment forms were complete for all patients to assess symptom improvement.


Sign in / Sign up

Export Citation Format

Share Document