Baseline Competency Assessment of Pharmacists Prescribing and Managing Vancomycin Therapy in the Regina Qu'Appelle Health Region

Background

Pharmacists in the Regina Qu'Appelle Health Region (RQHR), Saskatchewan, independently dose, monitor, and adjust vancomycin therapy. No framework exists for ongoing competency assessment of pharmacists.

Objectives

The primary objective was to determine pharmacists' overall level of competency for all components of the vancomycin prescribing procedure. The secondary objectives were to determine competency for individual prescribing phases, to stratify overall competency in relation to pharmacist and patient factors, and to identify the 3 most frequent errors.

Methods

A retrospective chart audit was performed of patients who received a prescription for vancomycin between November 1, 2015, and January 31, 2016. Patients were included if they received pharmacist-prescribed vancomycin as an inpatient or outpatient of an RQHR facility. Patients under the care of a pediatrician, those receiving vancomycin for surgical prophylaxis or via any route other than the IV route, and those whose vancomycin was prescribed by a current pharmacy resident were excluded. A rubric was created that assigned a numeric value for the appropriate completion of various procedure criteria.

Results

A total of 326 patients received vancomycin during the study period, of whom 200 met the inclusion criteria, representing 511 discrete episodes of prescribing by 42 pharmacists. The median overall competency rate, for all phases of prescribing, was 100% (interquartile range [IQR] 90.1%-100%). The median competency rates for the empiric therapy and monitoring phases were 94.4% (IQR 88.9%-100%) and 100% (IQR 87.5%-100%), respectively. No statistically significant differences were found in relation to pharmacists' experience or postbaccalaureate education, patients' level of acuity, or timing of prescribing. The competency score was significantly higher among pharmacists prescribing for patients with normal renal function than among those prescribing for patients with reduced renal function (p = 0.008). The 3 most common errors were failure to document risk factors for nephrotoxicity, failure to document requirement to obtain future trough levels, and failure to document that samples for trough levels had been drawn correctly.

Conclusions

During the study period, pharmacists at RQHR showed competency in all phases of vancomycin prescribing using the approved procedure. Documentation of clinical plans and assessments was identified as an area for improvement.

Effects of vancomycin, daptomycin, and tigecycline on coagulase-negative staphylococcus biofilm and bacterial viability within biofilm: an in vitro biofilm model

Bacteria may hide in a hydrated polysaccharide matrix known as a biofilm. The structure of the bacterial biofilm renders phagocytosis difficult and increases antibiotic resistance. We hypothesized that repeated doses of antibiotics have an effect on bacteria within the biofilm and that it could inhibit or eradicate biofilm formation. Two clinical biofilm-positive coagulase-negative staphylococcus isolates were evaluated. The effects of antibiotics on preformed and nascent biofilm and on bacterial eradication within the biofilm were determined using different doses of vancomycin, daptomycin, and tigecycline for different durations in an in vitro biofilm model. Vancomycin neither penetrated the biofilm nor had any microbicidal effect on bacteria within the biofilm. Daptomycin had a microbicidal effect on bacteria within the biofilm but had no effect on biofilm inhibition and eradication (independent from dose and treatment time). Tigecycline inhibited and eradicated biofilm formation and had a microbicidal effect on bacteria within the biofilm. In conclusion, (i) biofilm formation appeared to be a major barrier to vancomycin activity, (ii) daptomycin had an antimicrobial effect on the bacteria within the biofilm but not on the biofilm burden, and (iii) tigecycline had effects both on bacteria within the biofilm and on biofilm burden. Thus, both tigecycline and daptomycin might be promising candidates for the treatment of biofilm infections.

Effect of pycnogenol and spirulina on vancomycin-induced renal cortical oxidative stress, apoptosis, and autophagy in adult male albino rat

Vancomycin-induced nephrotoxicity has been reported to occur in 5%-25% of patients who were administered with it. Several natural antioxidants were found to be effective against drug-induced toxicity. We evaluated the possible protective effects of spirulina and pycnogenol alone or in combination on vancomycin-induced renal cortical oxidative stress. Forty-nine rats were randomly divided into 7 groups: group I, control; group II, received spirulina 1000 mg/kg per day; group III, received pycnogenol 200 mg/kg per day; group IV, received vancomycin 200 mg/kg per day every 12 h; group V, (spirulina + vancomycin); group VI, (pycnogenol + vancomycin); and group VII, (pycnogenol + spirulina + vancomycin). At the end of the experiment, kidney functions were estimated and then the kidneys were removed, weighed, and sampled for histopathological, immunohistochemistry, and biochemical studies. Administration of spirulina and pycnogenol alone or in combination decreased elevated serum creatinine, blood urea nitrogen, renal malondialdehyde, and immunoexpression of the proapoptotic protein (Bax), autophagic marker protein (LC3/B), and inducible nitric oxide synthase induced by vancomycin. They increased reduced glutathione, glutathione peroxidase, superoxide dismutase, and immunoexpression of the antiapoptotic protein (Bcl2). They also ameliorated the morphological changes induced by vancomycin. The combination therapy of spirulina and pycnogenol showed better protective effects than the corresponding monotherapy.

Specific inhibitors for identifying pathways for methane production from carbon monoxide by a nonadapted anaerobic mixed culture

Specific inhibitors such as 2-bromoethanesulfonate (BES) and vancomycin were employed in activity batch tests to decipher metabolic pathways that are preferentially used by a mixed anaerobic consortium (sludge from an anaerobic digester) to transform carbon monoxide (CO) into methane (CH4). We first evaluated the inhibitory effect of both BES and vancomycin on the microbial community, as well as the efficiency and stability of vancomycin at 35 °C, over time. The activity tests with CO2-H2, CO, glucose, acetate, formate, propionate, butyrate, methanol, and ethanol showed that vancomycin does not inhibit some Gram-negative bacteria, and 50 mmol/L BES effectively blocks CH4 production in the sludge. However, when sludge was incubated with propionate, butyrate, methanol, or ethanol as the sole energy and carbon source, methanogenesis was only partially inhibited by BES. Separate tests showed that 0.07 mmol/L vancomycin is enough to maintain its inhibitory efficiency and stability in the population for at least 32 days at 35 °C. Using the inhibitors above, it was demonstrated that CO conversion to CH4 is an indirect, 2-step process, in which the CO is converted first to acetate and subsequently to CH4.