4 Discussion
After coronary bypass (CABG) operations became routine procedures in
many centers, various scientific studies were conducted on each phase of
CABG operations. We now know that postoperative bleeding is a serious
cause of mortality and morbidity19,20,21. Bleeding may
cause end organ damage due to low perfusion, which may lead to increased
intensive care stay and hospital costs, cerebrovascular events, renal
failure, mesentery ischemia, liver damage and ultimately, mortality19,20,21. Therefore, postoperative bleeding is one of
the nightmares of surgeons. Blood product transfusion, performed to
avoid these complications caused by hypovolemia and low oxygen supply,
is a risky procedure itself. Studies have shown that febrile reactions,
renal dysfunction, respiratory distress, immunosuppression, infections,
and even low cardiac output can occur after blood product
transfusion22,23. Our aim in this study was not to
re-prove all this information, but by including only diabetic patients
treated with CABG, to predict more clearly the risk of bleeding in the
early period in a limited patient population. The progression of massive
bleeding is clear. The reason we included only diabetic patients in our
study is that diabetes is one of the biggest vascular damage
predictors 24, its association with atherosclerotic
heart disease is high25, and cardiovascular disease is
the cause of mortality in approximately 75% of diabetic
patients 26.
The mean BMI values of patients in the E-CABG Group 2-3 is lower than
those in Group 1-2. In PAPWORTH risk scoring, low BMI is a risk factor
for postoperative bleeding 11. Frankly, we could not
find the mechanism explaining the relationship between BMI and bleeding
in our literature review. However, BMI is calculated
as kg/m2 ORS’ as a risk parameter.
1,3. It can be suggested that patients with normal
preoperative hemogram (or hematocrit) values will need less transfusion
in the postoperative period. The number of platelets, which are the
basic elements of the coagulation system, and their functional capacity,
are also effective on postoperative bleeding 27,28,29
Our study included on-pump CABG patients. It is a known fact that the
heart-lung machine causes end organ damage 30 due to
changes in microcirculation and blood pressure, as well as microthrombi31,3233 RS list. Among the bleeding scores, only
Will-Bleed and Trust scores examine kidney functions. We believe this to
be deficiency of Papworth and Track.
There may be differences between genders in terms of clinical course and
diseases. In the evaluation of postoperative bleeding, the female gender
was at higher risk 34,35
In our study, age, hypertension, pulmonary hypertension, COPD, and
peripheral vascular diseases were not associated with postoperative
bleeding. Interestingly, no significant results were obtained in terms
of the tendency to bleed postoperatively in patients who were taken to
emergency surgery. Antiplatelet agents are one of the main therapeutic
agents in coronary artery diseases 36. While
discontinuation of acetylsalicylic acid (ASA) before the operation is
not recommended, clopidogrel and the less frequently used ticagrelor
should be discontinued at least 5 days before the
operation 36. Patients receiving ticagrelor were not
included in the study. However, those using clopidogrel and ASA were not
evaluated in separate groups. This can be considered the biggest
limitation of our study. We can attribute the lack of statistically
significant bleeding in patients undergoing emergency surgery to two
reasons: The fact that the number of patients using clopidogrel and
undergoing emergency operation is lower than those using ASA, and
patients undergoing emergency surgery have recently been diagnosed with
CAD and therefore have not received antiplatelet therapy before the
operation. Ultimately, as clearly shown in the guidelines, the amount of
postoperative bleeding may vary depending on the type of antiplatelet
agent, and this is a proven fact that cannot be ignored for the timing
of the operation 36. Therefore, preoperative use of
antiplatelets will be included in our ORS, which we plan to present with
larger case numbers in the future.