Fig: Mechanism of action of Midazolam
It was searched for studies published up to May 2014 in the Cochrane
Central Register of Controlled Trials, MEDLINE, EMBASE, and the
Institute for Scientific Information (ISI), Web of Science, and
reference lists of publications published up to May 2014. To look for
unpublished research, we contacted pharmaceutical companies and examined
databases such as the Science Citation Index, ClinicalTrials.gov, and
the Current Controlled Trials for relevant information. The linguistic
requirements for our participants were not specified ahead of time. In
May 2015, we re-ran the search and uncovered nine new papers that we
believe should be investigated in greater depth. When we amend the
review, we will take new research into consideration.
In order to be considered for the study, the researchers had to compare
Dexmeditomidine to a placebo or another medication commonly used during
abdominal surgery in adults. Participants who required ”rescue”
analgesia, postoperative sedation, PONV, time to first flatus and stool
passage, and time to first out-of-bed mobilization were also evaluated
in the trials.
Following the screening of the titles and abstracts for eligibility, the
data was individually assessed for relevance by two review authors, who
worked in parallel. Using a data collecting form, all relevant
information from the studies included was retrieved, and the risk of
bias was assessed. We were able to work out our differences with the
third reviewer. As part of the risk of bias assessment and data
extraction process, we contacted research authors or, where applicable,
co-authors from current or previous studies to obtain additional
information relevant to their work.
The following are the most important findings: There were a total of 492
participants in the seven studies that were included in our systematic
review. The total number of participants in our study is 422 people.
Over a dozen queries are still being treated as classified. With the
exception of one study (80 participants) that discovered an increase in
postoperative pain, six studies involving 402 participants compared
Dexmeditomidine to placebo and discovered a reduction in ”rescue” opioid
consumption in the first 24 hours after surgery, but no clinically
significant differences in postoperative pain (as measured by a VAS
ranging from 0 to 100 mm, with 100 being the worst possible pain).
Because of the high heterogeneity that results from pooling data,
statistical meta-analyses were deemed inappropriate in this case.
Because of a lack of precision and the risk of bias, the evidence for
our major outcomes was of extremely low quality, as was the evidence for
our minor outcomes. A scarcity of evidence, as well as estimations that
were either erroneous or of poor methodological quality, undermined our
secondary aims.
The data on the comparison of Dexmeditomidine and fentanyl were
insufficient to draw any definitive conclusions (one study, 20
participants).
The following are the authors’ main conclusions: It appeared to have
some opioid sparing effects when Dexmeditomidine was given
preoperatively to treat acute pain following abdominal surgery in
adults, but it had no detectable effect on postoperative pain when
compared to a placebo. Several factors contributed to the poor quality
of the evidence, including typographical errors, methodological
limitations, and a high degree of heterogeneity across the seven studies
that were included. In part due to the fact that the effect of
Dexmeditomidine on crucial patient outcomes such as gastrointestinal
function, mobilization, and side effects could not be fully evaluated,
the drug’s clinical utility for patients is currently unknown. Because
all of the included studies were too small to be taken into account,
there was no way to rule out publication bias completely. The data was
confined to middle-aged individuals who were in good health and were
receiving elective abdominal surgery at the time of the study. Although
a considerable quantity of data from trials containing combination
surgery was not available, it is possible that this contributed to a
potential bias in the results. A higher number of studies with longer
follow-up periods are required in order to uncover and evaluate
patient-important outcomes.