Methods
A systematic literature review was conducted using the PubMed/MedLine,
CINAHL Plus, Global Health and Embase databases. We sought to retrieve
all studies of reasonable quality which assessed the impact of
antimicrobial cycling strategies on bacterial resistance within clinical
settings. We also recorded
antimicrobial consumption and morbidity and/or mortality rates as
secondary outcomes for a more thorough assessment of the observed
results.
As this study was part of a wider project we designed a broad search
algorithm on the basis of definitions provided by major organizations:
Infectious Diseases Society of America (IDSA), Center for Disease
Prevention and Control (CDC)[11][12]. The search string covered
three concepts, antimicrobial stewardship and its constituent
strategies, antimicrobial resistance, and the hospital setting of the
interventions:
- (antimicrobial stewardship) OR (antibiotic stewardship) OR (audit
“and” feedback) OR (restriction) OR (pre?authorization) OR
(antibiotic combination*) OR (antimicrobial combination*) OR
(antibiotic cycling) OR (antimicrobial cycling) OR (antibiotic
rotation) OR (antimicrobial rotation) OR (antibiotic time?out*) OR
(antimicrobial time?out*) OR (dose adjustment) OR (dose optimi#ation)
OR (antibiotic mixing) OR (antimicrobial mixing) OR (antibiotic
de?escalation) OR (antimicrobial de?escalation) OR (parenteral oral
conversion) OR (intravenous oral conversion) OR (procalcitonin) OR
(electronic alert*) OR (electronic system*) OR (computeri#ed alert*)
OR (computeri#ed system*) OR (automat* stop order*)
- Exp Drug Utilization
- 1 OR 2
- (antibiotic resistan*) OR (antimicrobial resistan*) OR (multi?drug
resistan*) OR (bacterial resistan*) OR (bacterial susceptib*) OR
(susceptib* phenotype*) OR (antibiotic susceptib*) OR (antimicrobial
susceptib*)
- 3 AND 4
- (nosocomial OR hospital* OR in?patient OR intensive care OR ICU*)
- 5 AND 6
8,922 papers covering the period to 1st April 2020 were screened for
relevance. Randomised studies were scarce and for this reason we decided
to broaden inclusion criteria by considering quasi-experimental designs.
However, we excluded simple before-and-after studies which examined
cohorts lasting less than one year, to minimise confounding due to
seasonality and to facilitate comparability of results. We also excluded
studies which combined changes in infection control practices or applied
multidisciplinary interventions due to confounding and constraints on
comparability. Studies which
lacked historical or parallel cohorts for comparison were not included
as interpretation is impossible without some kind of internal control or
comparator. Data provided by grey literature such as congress papers and
reports from governmental and non-governmental organizations were
outside our scope due to lack of peer review. Finally, studies which did
not apply suitable statistical methods to evaluate the significance of
the reported results were also excluded.
A main distinction from prior meta-research on the topic is the fact
that we considered changes in infection control as well as the
application of additional antimicrobial stewardship interventions as
important confounding factors which should not be overlooked; this led
to the exclusion of several papers which other reviews have included.