Letter:
Dear Editor,
We have read the article “What are the factors affecting the
progression of kidney failure, mortality and morbidity after cardiac
surgery in patients with chronic kidney disease” by Bedih Balkan MD et
al.1 The author’s efforts regarding this sensitive
topic are highly appreciated and need to be acknowledged by readers.
We agree with the conclusion of the article that Age, Complications,
Euro score, Cross clamp time, Pulmonary artery pressure, Postoperative
BUN, Creatinine, and CKD-EPI GFR were found to be effective in
predicting 30 days mortality of patients. However, few concerns arise
regarding the validity of the study.
Firstly, the single-centered study and unavailability of particular
socioeconomic status were not mentioned. For example, a study by Colleen
Gorman Koch et al.2 has explained that Lower
socioeconomic status is associated with lower risk-adjusted quality of
life for patients undergoing cardiac surgery. Therefore, further
characterization of risk factors for the poor quality of life offers an
opportunity for intervention. Secondly, the small sample size may have
an impact on the rationale for the findings. A study by Charles E Hobson
et al.3 included 2973 patient cases that increased the
power of their study, and the findings seemed legitimate. Third, the
author should have specified the ethnic origin of the patients in the
study because it could further specify the type of diversity of the
population. For instance, a 2021 study by Micheal Heung MD et
al.4 has explained the role of race on Acute kidney
injury after cardiac surgery. The author has concluded that Black
patients had a 50% increased odds of having moderate to severe
postoperative AKI compared with White patients. Fourth, the author has
excluded the pediatric population (people under age 18) from the study
even though this population has a major contribution to cardiac
surgeries with AKI. A 2022 study by Jef Van den Eydne et
al.5 has evaluated a variety of biomarkers as
predictors of cardiac surgery-associated AKI in children (under 18
years), which were the most prominent with excellent diagnostic
qualities. Fifth, the author has not mentioned preoperative protective
strategies to prevent postoperative AKI. A study by Isabell A . just MD
et al.6 has mentioned preoperative fluid management as
a preventive strategy for AKI after cardiac surgery to validate this
point. Finally, the author should have mentioned long-term mortality
instead of 30 days mortality in patients with CKD after cardiac surgery.
For example, a study by Alas klavek et al.7 has
explained a 5-year experience with cardiac surgery procedures in
dialysis-dependent patients. He has suggested the predictors of
increased late mortality as Heart failure, Urgent/emergent surgery, the
complexity of surgical procedures, and postoperative low cardiac output
syndrome.