Pharmacy

Permanent URI for this collectionhttps://uwspace.uwaterloo.ca/handle/10012/9947

This is the collection for the University of Waterloo's School of Pharmacy, which includes papers submitted at the conclusion of pharmacy residencies administrated by the School of Pharmacy.

Research outputs are organized by type (eg. Master Thesis, Article, Conference Paper).

Waterloo faculty, students, and staff can contact us or visit the UWSpace guide to learn more about depositing their research.

Browse

Browsing Pharmacy by Author "Hussein, Abdulkadir A."

Filter results by typing the first few letters
Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Determination of the relationship between vancomycin trough concentrations and the AUC/MIC Dosing
    (University of Waterloo, 2020-07-15) Ing, Nathan; McQueen, Joe; Nadeau, Lynn; Hussein, Abdulkadir A.
    Rationale: The recently revised guidelines for the therapeutic monitoring of vancomycin recommend targeting an AUC/MIC of 400-600 for serious methicillin-resistant Staphylococcus aureus (MRSA) infections. The feasibility of transitioning from trough-based dosing to dosing by AUC/MIC warrants further study as the latter method has been shown to require additional pharmacist training and increased costs secondary to laboratory monitoring and specialty software. Methods: This was a prospective, non-randomized, single-centre trial conducted over eight months. Adult inpatients receiving vancomycin for greater than three days for the treatment of serious MRSA infections were included in the study. The AUC/MIC was calculated using two-point pharmacokinetic equations from peak and trough concentrations. The primary outcome was to determine the relationship between vancomycin trough concentrations and the AUC/MIC. Secondary objectives were to assess the difference in vancomycin doses and rates of acute kidney injury (AKI) between traditional trough-based dosing and AUC/MIC dosing. Results: 234 patients received vancomycin over the study period and 32 patients met the inclusion criteria; 36 sets of vancomycin levels were obtained. Sites of infection included skin and soft tissue (31.2%), bacteremia (21.9%), pneumonia (18.8%), osteomyelitis (15.6%) and miscellaneous (12.5%). Vancomycin trough concentrations of 10.8-16.1 mg/L correlated to an AUC/MIC of 400-600 with 95% probability (r2=0.75). The average total daily doses for trough-based and AUC/MIC dosing were 1590.28 mg and 1281.25 mg, respectively. The mean difference in dose between the two dosing strategies was 309 mg (p=0.179). There were no significant differences in the rates of AKI between trough-based dosing and dosing by AUC/MIC [OR=1.791; 95% CI (0.119,48.048)]. Conclusion: On average, vancomycin trough concentrations of approximately 11-16 mg/L correlated strongly with an AUC/MIC of 400-600, suggesting that adopting the cumbersome and costly strategy of AUC/MIC targeted dosing may be unnecessary, but further study is required. This correlation also suggests that aggressively targeting vancomycin troughs of 15-20 mg/L, as previously recommended, is unwarranted. Average daily doses and rates of AKI did not significantly differ between trough-based dosing and dosing by AUC/MIC.
  • Thumbnail Image
    Item
    Risk and Benefit of Warfarin for Primary Prevention in Atrial Fibrillation Patients on Hemodialysis: A Retrospective Pilot Study
    (University of Waterloo, 2019-07) Andrei, Alexandra; Hussein, Abdulkadir A.; Zagar, Joseph; Soong, Derrick
    Rationale: Although warfarin is an established anticoagulation therapy for prevention of ischemic strokes in patients with atrial fibrillation, studies reporting INR values with correlation to warfarin efficacy and safety outcomes in patients on hemodialysis with atrial fibrillation are scarce. The purpose of this study was provide additional information to aid in optimizing future clinical anticoagulation decisions for patients with atrial fibrillation on hemodialysis. Methods: A retrospective cohort study was conducted from April 2011 to January 2019 at a regional kidney dialysis centre in southwestern Ontario, Canada. The primary objective of this study was to correlate achieved INR measurements with the efficacy and safety of warfarin anticoagulation. Results: A total of 286 patients were reviewed and 25 patients were included. No ischemic strokes were reported and six bleeding episodes occurred. The mean INR of the 25 patients was 2.4 (SD±0.47) with an average follow up of 336 days. Using a Cox Proportional Hazards Model, univariate correlations between risk of bleeding and baseline characteristics were examined and no statistically significant correlations were found. Conclusion: Patients on hemodialysis with atrial fibrillation may have a higher bleeding rate while on warfarin despite having therapeutic IN Rs. This may be attributed to the small sample size, duration of observation and factors such as intra-dialysis heparin use and uremic platelet dysfunction. Therefore, initiating warfarin for primary prevention in this patient population requires a careful assessment of bleeding risk factors. Further studies are warranted.