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P J Jewesson

Publications and source records attributed to P J Jewesson.

At least 37 records · Page 2Linked to original sources
PubMed1990

Application of a modified bioassay for monitoring serum teicoplanin and vancomycin in febrile neutropenic patients.

Teicoplanin is a glycopeptide antibiotic with a mode of action and spectrum of activity similar to those of vancomycin. Its efficacy and tolerability as empiric therapy and its pharmacokinetic properties in neutropenic patients are being studied in a double-blinded, randomized trial in comparison with those of vancomycin. We report here a modified agar diffusion bioassay which is suitable for monitoring levels of either teicoplanin or vancomycin in serum during combination therapy with beta-lactams, aminoglycosides, and amphotericin B. Serum samples spiked with either teicoplanin or vancomycin gave reproducible results (mean coefficient of variation, 8.8%) regardless of the presence of tobramycin, amikacin, piperacillin, ceftazidime, amphotericin B, or their combinations. Among 25 patients who received teicoplanin at a dosing schedule of 6 mg/kg every 24 h intravenously, steady state was reached after 14.2 +/- 4.0 days, and 1-h peak and trough concentrations of teicoplanin in serum at steady state were 40.8 +/- 15.0 and 12.5 +/- 3.2 mg/liter, respectively. In contrast, among 25 patients who received vancomycin at a dosing schedule of 15 mg/kg every 12 h intravenously, steady state was reached by 24 h, and the 1-h peak and trough concentrations in serum were 37.5 +/- 15.6 and 8.3 +/- 3.8 mg/liter, respectively. The elimination half-lives for teicoplanin estimated by two separate approaches agreed closely with each other: 80.5 +/- 21.5 h by an accumulation model (M. Gilbaldi and D. Perrier, Pharmacokinetics, 2nd ed., p. 121, 1982) and 87.3 +/- 19.3 h as predicted from the degree of renal function (M. Rowland, Clin. Pharmacokinetic 18:184-209, 1990). These values were 14- to 15-fold higher than that for vancomycin (5.6 +/- 1.8 h). Since considerable variability was noted in the pharmacokinetic parameters for both teicoplanin and vancomycin among the individual patients, our data further emphasized the need for frequent monitoring of these drugs during empiric therapy of the febrile neutropenic patient.

Adult↗
PubMed1989

Adverse reactions in a dose-ranging study with a new long-acting fluoroquinolone, fleroxacin.

New fluoroquinolones have generally been well tolerated. In a double-blind evaluation of oral fleroxacin, using 400, 600, or 800 mg once daily for 7 days in an ambulatory setting for treatment of uncomplicated genital infections, we encountered unexpectedly high rates of adverse reactions. The objective of this analysis was to determine whether any factors in addition to dose could be found to account for our observations. Adverse reactions developed in 66 (84%) of 79 individuals, and severe reactions arose in 38 (48%). Most frequent were central nervous system reactions (70%), with insomnia being especially frequent (49%); gastrointestinal reactions (39%) and photosensitivity reactions (10%) were also common. Development of any reaction (central nervous system reactions, insomnia, and severe intestinal reactions) was dose related. Development of photosensitivity reactions correlated with an outdoor occupation. No other factors, including usual daily caffeine use, correlated with the development of adverse reactions. In our study, fleroxacin taken as a single daily 600- or 800-mg dose was associated with an unacceptably high rate of adverse reactions. Other studies are required to determine whether this problem is unique to fleroxacin or will occur with higher doses of other fluoroquinolones possessing similar chemical modifications and/or good tissue penetration and very long half-lives.

Adolescent↗
PubMed1989

Impact of a two-stage intervention program on cefazolin usage at a major teaching hospital.

To reduce antimicrobial drug costs associated with the administration of cefazolin, a two-stage therapeutic intervention--employing persuasive (informational) and power (therapeutic interchange) strategies--was initiated at this 1,000-bed major Canadian teaching hospital. The target of the intervention was to extend the dosage interval of cefazolin to q8h. During a 12-week preimplementation period, 32% of orders specified 8-hour dosage intervals. This percentage increased to 58% after the 3-week, initial informational stage of the intervention. When therapeutic interchange was employed, the percentage of orders for extended intervals rose to an average of 97% over a 32-week postimplementation period. An estimated annual cost savings of $58,000 resulted from this intervention. Manpower requirements to implement and maintain this program were minimal and prescriber antagonism was not encountered.

British Columbia↗
PubMed1988

Drug usage review of cefamandole at a teaching hospital.

A drug usage audit of cefamandole was conducted at a 900-bed teaching hospital. Health records of all in-patients receiving cefamandole during a three-month period (November 1, 1985 to January 31, 1986) were retrospectively reviewed. Treatment of lower respiratory tract infections accounted for 35 (44%) of the 79 treatment courses examined. Surgical antimicrobial prophylaxis for cardiovascular procedures involved 26 (33%) courses of therapy and 15 (19%) courses were associated with biliary tract procedures. The three remaining treatment courses (4%) included therapy for septicemia, orthopedic surgery prophylaxis, and a leg ulcer. Twenty-eight percent of all treatment courses were deemed to be appropriate. Thirty-two percent were considered controversial, and 40 percent inappropriate. The majority of the suboptimal use identified involved prescribing cefamandole for cardiovascular surgery prophylaxis. The role of cefamandole in the acute hospital setting is reviewed with reference to other available first, second and third-generation cephalosporins. General recommendations for its use are outlined.

Anti-Bacterial Agents↗
PubMed1985

Quality of use of parenteral metronidazole therapy in a teaching hospital.

The recent release, relatively high cost and potential adverse effects of parenterally administered metronidazole prompted a quality-of-use audit at a 1000-bed teaching hospital. Ninety-two courses of treatment in 81 inpatients during a 6-week period were studied. Appropriateness of therapy was assessed on the basis of published indications. Parenterally administered metronidazole was prescribed primarily in anaerobic and anaerobic-aerobic infections. It was used as frequently for prophylaxis as for therapy. Surgical services accounted for 95% of the treatment courses. Inappropriate use was noted in 27 (29%) of the courses: agents other than parenterally administered metronidazole were indicated in 12 (13%), while the dose, dosing interval or duration of treatment was suboptimal in 15 (16%). Substantial savings would be achieved if oral or rectal metronidazole therapy were substituted for intravenous therapy for perioperative prophylaxis in elective colorectal surgery. Written justification for use and automatic stop orders are recommended to improve the cost effectiveness of both prophylactic and therapeutic use of selected antimicrobial agents.

Bacterial Infections↗
PubMed1985

Influence of body fat on the volume of distribution of theophylline.

Twenty-six acutely bronchospastic patients admitted to the emergency room of an acute care hospital were studied to determine the influence of body fat on the volume of distribution (Vd) of theophylline. Total body weight (TBW), height, skinfold thickness (at three sites), and theophylline levels around an intravenous aminophylline dose were measured. Ideal body weight (IBW), percentage of body fat, and absolute and relative Vd of theophylline were calculated. Vd of theophylline correlated better with IBW than TBW. No relationship was identified between Vd normalized to IBW and either percentage of body fat or the ratio of TBW to IBW. This indicates that in our sample (0.8 IBW less than TBW less than 1.4 IBW), distribution of theophylline into adipose tissue was not an important determinant of Vd. Theophylline's Vd was best estimated by the formula Vd (L) = 0.419(L/kg) X IBW(kg).

Adipose Tissue↗
PubMed1985

The influence of a hospital pharmacy residency program on career advancement and satisfaction.

A mail survey of practicing hospital pharmacists in British Columbia who graduated since the introduction of hospital residency programs was conducted to determine the influence of a hospital pharmacy residency program on career advancement and satisfaction. Respondents included 33 past residents and 38 non residents. Career advancement was measured by union grade level. Professional and employment satisfaction were assessed using a five-level satisfaction scale. Percentage time allocated to each of administrative, clinical, distributional and research activities was determined for each group. Past residents were also requested to estimate residency program time allocation devoted to these activities which would best prepare them for their present employment. The results of this study indicate that in the ten years the program has been in operation, no difference can be demonstrated between past residents and non residents with respect to career advancement, professional satisfaction or employment satisfaction. Past residents recommend that a hospital residency should consist of approximately 40% clinical activities, 30% distributional activities and the remainder time allocated equally to administrative and research activities. Further research is recommended to evaluate the impact of a hospital pharmacy residency program in a location independent of union grade restrictions and later in the career of past residents to determine the influence of these factors on career advancement and satisfaction.

British Columbia↗
PubMed1983

Auditing antibiotic use in a teaching hospital: focus on cefoxitin.

The prevalence and nature of antibiotic misuse in a major teaching hospital was assessed by means of a quality-of-use audit. Cefoxitin was chosen for study. The use of cefoxitin increased rapidly during the study period, accounting for 17.7% ($15300) of the pharmacy's costs for cephalosporins during the first year of its availability but 47.7% ($60707) during the second year. Cefoxitin was inappropriately used for 43% of the patients receiving it during the first 2-month audit period and for 25% of those receiving it during the second audit period, 1 year later (p less than 0.01 by chi-square analysis).

Anti-Bacterial Agents↗
PubMedDate not supplied

Pharmacokinetics and safety of antimicrobial agents during pregnancy.

The use of antimicrobial agents during pregnancy poses unique concerns because of both potential toxicity and special pharmacokinetic considerations that have important therapeutic implications for both mother and fetus. Various physiologic adaptations occur with advancing gestation, including marked increases in maternal intravascular volume, glomerular filtration, and hepatic and metabolic activities; thinning and maturation of the fetomaternal membrane; and increases in transplacental diffusion capacity. The net result is that maternal antimicrobial concentrations tend to be 10%-50% lower in late pregnancy and the immediate postpartum period than in the nonpregnant state. Placental transfer of antimicrobial agents and their excretion in amniotic fluid or breast milk are similarly affected by hemodynamic changes, membrane transport characteristics, and maturation or metabolic activity of the specific organs involved. Review of the literature suggests that, although the need for caution in the use of antimicrobial agents during pregnancy has been well emphasized, firm data on the pharmacokinetics, efficacy, and optimal use of these drugs in this situation are extremely sparse and urgently needed. However, recommendations regarding the use of specific antibacterial, antifungal, antiviral, and antiparasitic agents against selected infections during pregnancy can be made.

Anti-Bacterial Agents↗
PubMedDate not supplied

Implementation and evaluation of a standardized herpes simplex virus prophylaxis protocol on a leukemia/bone marrow transplant unit.

OBJECTIVE: To assess the impact of a standardized acyclovir prophylaxis protocol for the prevention of herpes simplex virus (HSV) infection and disease in bone marrow transplant and leukemic patients. DESIGN: Two-phase, open sequential study involving prospective patient monitoring and retrospective health record review. SETTING: Tertiary care teaching hospital. PATIENTS: Fifty-seven patients (35 preprotocol, 22 postprotocol) who received acyclovir for HSV prophylaxis during an 18-month study period. INTERVENTIONS: An acyclovir HSV prophylaxis protocol was developed and implemented. Under this protocol, all HSV immunoglobulin G-seropositive hematology patients received an acyclovir regimen of 125 mg/m2 i.v. q6h or 600 mg p.o. q6h (if tolerated) from day -5 to day 30. Regimens not matching protocol were modified by pharmacists in conjunction with the prescriber. All treatment courses were followed daily by pharmacists to modify dosage according to renal function and assess appropriateness of the i.v. route. Tablets, capsules, or suspensions were promoted if the patient was considered tolerant of the oral route. MAIN OUTCOME PARAMETERS: Outcome parameters included (1) incidence of parenteral, oral, or combined therapy; (2) total prophylactic acyclovir dose per patient; (3) mean prophylactic acyclovir daily dose; (4) mean duration of acyclovir prophylaxis; and (5) HSV reactivation rate. RESULTS: Following implementation of the protocol, the mean total i.v. acyclovir dose per patient decreased from 20.1 g (range 3.6-109.5) to 11.7 g (range 1.0-43.0; p = 0.1162). The mean cumulative oral dose increased from 12.1 g (range 0.4-70.0) to 33.1 g (range 2.4-93.6; p = 0.0007). Mean duration of therapy increased from 27.6 to 33.5 days (p = 0.23). The mean duration of oral therapy increased from 10.5 days (+/- SD 10.9) to 17.2 days (+/- SD 12.1) (p = 0.034). The appropriateness of use of the i.v. dosage form increased from 53 to 88 percent of treatment days (p = 0.013). No difference in HSV reactivation rate was observed when comparing patients prior to and following protocol implementation. A drug acquisition savings of $1112.00 (CDN) per patient was realized. CONCLUSIONS: The implementation of a standardized HSV acyclovir prophylaxis protocol has resulted in significant drug acquisition cost savings without an apparent negative impact on patient outcome.

Acyclovir↗