Due to thelarge number of patients who develop diabetes mellitus type 2 and the tendency
to use radiological methods to avoid invasive procedures, it is becoming
increasingly frequent to find patients undergoing metformin treatments who are
being given intravascular iodinated contrast media. Traditionally, the fear
that this can be linked to lactic acidosis has always existed, despite no
proven evidence to support this theory.
The
prevalence and incidence rate of diabetes mellitus type 2 is currently
increasing; in most patients, the disease’s treatment is still based on the
administering of metformin, along with a change of life style. Also, the number
of patients who undergo radiological examinations, in which some form of
intravascular iodinated contrast media is used, is increasing every day.
Traditionally, metformin was withdrawn from those patients who needed to
undergo studies involving intravascular iodinated contrast media due to the
risk of developing lactic acidosis which, although not very frequent, has a
very high mortality rate (40%). However, the evidence supporting this is based
on isolated cases which have been researched using heterogeneous studies.
Intravascular iodinated contrast media are not a stand-alone
risk factor of lactic acidosis in patients that take metformin, but rather they
become relevant when other underlying kidney disorders are also present. Taking this into account, we can establish a causal link because
the use of intravascular iodinated contrast media does suppose a risk of
developing kidney failure; this risk can be stratified depending on each
patient’s characteristics. According to this there is a possibility of
developing contrast-induced nephropathy. A set of variables were established
and given a value; according to the total sum, the risk of developing a
nephropathy can be calculated. The variables were: systolic blood pressure
below 80mmHg, intra-aortic balloon pump, grade 3-4 heart failure or a history
of acute lung edema, being over 75 years of age, packed cell volume below 39%
in men or below 36% in women, diabetes mellitus, contrast volume and glomerular
filtration (which greatly affects the final assessment).
No comments:
Post a Comment