Download full PDF - UBC Medical Journal

YEAR 1
Introduction: Initial management of bacterial growth in blood
cultures (BC) usually includes broad-spectrum antibiotics. Once
speciation and an organism’s susceptibility is available, antibiotic
therapy should be adjusted. Physicians may be over-prescribing
drugs active against methicillin-resistant Staphylococcus
aureus (MRSA) such as vancomycin when drugs active against
methicillin-sensitive Staphylococcus aureus (MSSA)-active
would suffice. This practice may contribute to the emergence of
drug-resistant bacterial strains. The objective of this study was to
examine whether an antibiotic stewardship program (ASP) could
change the usage of MRSA-active drugs for patients with grampositive
(GP) bloodstream infections in the ICU.
Methods: Data from patients with BCs drawn from a single
tertiary centre ICU were analyzed. Positive blood cultures were
identified from the laboratory information system (SoftLab, SCC
Soft Computer, Clearwater FL). Patients were identified through
ICU admission books; data was collected retrospectively, using
patient paper files and electronic medical records. The analysis
of antibiotic usage was from January 2008 to July 2009. Data
analysis was performed using Student’s t-test for continuous
variables and chi-squared for dichotomous variables.
Results: A total of 103 and 43 episodes of GP infections were
identified, pre-ASP and post-ASP, respectively. The two groups
were similar in terms of demographics and severity of illness. Both
pre- and post-ASP, 95% of all GP bloodstream isolates were due to
coagulase-negative staphylococci. There was a 41% reduction in
the duration of vancomycin and linezolid following introduction
of the ASP. Overall usage of MRSA-active antibiotics was also
significantly reduced post-ASP while infection rates remained the
same. Central venous catheter dwell time was also reduced by a
mean of 5.3 days.
Conclusions: The proportion of MRSA-positive cultures in
the ICU when compared to other GP blood cultures does not
justify the high use of MRSA-active drugs. Introduction of an
antimicrobial stewardship program resulted in a 40% reduction
in vancomycin and linezolid use. The relationship of central line
dwell times to antibiotic use is unclear at present, but warrants
further investigation.
been shown to significantly reduce the severity and occurrence of
IDH, or its associated morbidity. Midodrine is frequently used at
the hemodialysis unit at this institution for the treatment of IDH
despite its unknown impact.
Objective: To evaluate midodrine use in the management of IDH
at the hemodialysis unit. The primary objectives were to observe
the impact of midodrine on BPs at various intervals during the
HD sessions, and its usage pattern on the unit. The secondary
objectives were to compare the patient characteristics and risk
factors between the midodrine and non-midodrine (control)
groups, while also determining the overall incidence of IDH and
non-midodrine interventions made.
Methods: A prospective observational review was conducted to
assess BPs, dosing and frequency of midodrine administration,
and the number of IDH episodes during hemodialysis sessions in
both midodrine and control groups. Patient characteristics and
risk factors influencing IDH were also compared between the two
groups. Descriptive statistics were used.
Results: Fifty-five midodrine patients and 53 non-midodrine
patients were included. The midodrine patients entered their
hemodialysis sessions with lower mean BPs than the control group
(123/65 vs. 133/70 mm Hg, respectively). This trend continued
during the hemodialysis sessions and may have increased the
susceptibility of these patients to IDH as this group also had
a higher rate of symptomatic IDH (12% vs. 4.8%). A mean
midodrine dose of 7.5 mg was used per hemodialysis session,
although the range was quite large. Patient characteristics were
found to be similar between the two groups.
Conclusions: This study revealed that midodrine was used
commonly for IDH at this hemodialysis unit despite a lack of
well documented clinical benefits. The midodrine users had lower
BP values throughout the hemodialysis sessions and experienced
more symptomatic IDH despite the use of midodrine.
Assessment of Midodrine Use in
the Management of Intradialytic
Hypotension (AMUSINg)
Kris Poinen BScPharm, Joanne Jung BScPharm,
Marianna Leung BScPharm PharmD; Mercedeh Kiaii
MD FRCP(C), Bev Jung MD FRCP(C), Nicole Gorman NP
1
Vancouver Coastal Health Authority (VCH)
2
St. Paul’s Hospital, Department of Pharmacy
3
St. Paul’s Hospital, Department of Nephrology
Background: Intradialytic hypotension (IDH) occurs frequently
in the hemodialysis setting and may increase morbidity and
mortality within this population. With its α-1 receptor agonist
action, midodrine is a potential treatment option for IDH. Although
midodrine may improve blood pressure (BP) values, it has not
UBCMJ | APRIL 2010 1(2) | www.ubcmj.com 4