Audit of antibiotic duration of therapy, appropriateness and outcome in patients with nosocomial pneumonia following the removal of an automatic stop-date policy.

Automatic stop-orders (ASOs) have been utilized to discourage inappropriately prolonged antibiotic therapy. An ASO policy, which required reordering of antibiotics after 7 days of therapy, had been in place at our institution prior to 2002, but was revoked after instances of compromised patient care due to inadvertent and inappropriate interruption of antimicrobial treatment. The objective of this study was to evaluate the impact of revoking the ASO policy on the duration of antibiotic therapy, infection-related outcome (cure vs failure), relapsing infection, occurrence of resistant bacteria and superinfection in patients with nosocomial pneumonia. A retrospective chart review of adult patients (≥ 18 years old) admitted to Sunnybrook Health Sciences Centre with nosocomial pneumonia requiring antibiotic therapy was conducted. Duration of antibiotic therapy, infection-related outcome (cure vs failure), rate of relapsing infection, resistant organisms and superinfection were determined for each cohort. Forty-six eligible adults with nosocomial pneumonia per cohort were included [corrected]. Duration of antibiotic therapy was not significantly different in the pre- (11.4 ± 3.8 days) compared with the post-ASO revocation cohort (10.8 ± 4.1 days; p=0.43). There were also no significant differences between the cohorts with regard to infection-related outcome (cure vs failure), relapsing infection, or the occurrence of resistant bacteria or superinfection (p>0.5). Revocation of the ASO policy for antibiotics at our institution was not associated with a longer duration of antibiotic therapy, or increased incidence of infection-related mortality, relapsing infection, resistant bacteria or superinfection for patients with nosocomial pneumonia.

Drug therapy in patients undergoing peritoneal dialysis. Clinical pharmacokinetic considerations.

Peritoneal dialysis has become an accepted treatment modality for end-stage renal disease. The introduction of continuous ambulatory peritoneal dialysis (CAPD) has further popularised this technique. The need for adjustment of drug dosage in patients with endstage renal disease and the need for supplemental dosages following haemodialysis are well recognised. Little documentation exists concerning the need for supplemental drug dosage in patients on peritoneal dialysis. Knowledge of the influence of peritoneal dialysis on the elimination of specific drugs is essential to the rational design of dosage regimens in patients undergoing this dialysis technique. This review addresses the clinical pharmacokinetic aspects of drug therapy in patients undergoing peritoneal dialysis and considers: the efficiency of the peritoneal membrane as a dialysing membrane; the effects of peritoneal dialysis on the pharmacokinetics of drugs; the pharmacokinetic models and estimation methods for peritoneal dialysis clearance and the effects of peritoneal dialysis on drug elimination; the influence of the pharmacokinetic parameters of drugs on drug dialysability; and the application of pharmacokinetic principles to the adjustment of drug dosage regimens in peritoneal dialysis patients. Data on drugs which have been studied in peritoneal dialysis are tabulated with inclusion of pharmacokinetic and dialysability information.

Space charge fields: a fringe technique for observing such fields during hologram writing in LiNbO(3).

An interference fringe method is reported that allows rapid monitoring of the large scale (nonsinusoidal) space charge field which develops during hologram writing with nonuniform light intensity in LiNbO(3). This large scale field is distinct from the sinusoidal space charge fields that constitute the hologram. The large scale field has been shown elsewhere to be important in that it affects the efficiency of hologram writing and leads to history effects. Using the fringe method, a dielectric breakdown process associated with the large scale field was observed which may have been responsible for some effects reported by Carlsen in his work on computer applications.