Pre- and Postoperative Urea Levels in Open Heart Surgery: Assessment as a Risk Factor for Predicting Mortality - A Retrospective Analysis

Urea Levels and Mortality in Open Heart Surgery

Authors

DOI:

https://doi.org/10.37609/srinmed.24

Keywords:

Awareness, treatment

Abstract

Background: Open-heart surgery, while essential for managing severe cardiovascular diseases, carries a high risk of postoperative complications, particularly acute kidney injury (AKI), associated with elevated urea levels. High urea reflects renal impairment and inflammatory stress, both of which impact patient survival, highlighting the need for reliable biomarkers to predict mortality and optimize perioperative care.

Aims: This study evaluated the predictive value of preoperative and postoperative urea levels in estimating mortality risk in open-heart surgery patients. Despite the established clinical importance of urea, its potential as a prognostic tool remains underutilized.

Methods: We conducted a retrospective analysis of patient data, focusing on the relationship between urea levels and mortality outcomes in individuals who had undergone open-heart surgery. Multivariate analyses were performed to assess the independent impact of urea levels on mortality risk.

Results: Findings showed that each unit increase in postoperative urea was linked to a 5% increase in mortality risk, underscoring its value as a prognostic indicator. Higher preoperative urea levels also correlated with decreased survival, particularly among high-risk patients.

Conclusions: Both preoperative and postoperative urea levels are critical indicators of mortality risk following open-heart surgery. Routine monitoring of these biomarkers could improve postoperative outcomes, especially for high-risk groups. This study supports incorporating urea levels into standard perioperative assessments to enhance patient survival rates.

Author Biographies

MD Çise Kanat Toprak, Mersin University Faculty of Medicine Hospital

Department of Child and Adolescent Psychiatry

Op. Dr. Hasan Cihan, Mersin University Faculty of Medicine Hospital

Department of Cardiovascular Surgery

References

Bucerius J, Gummert JF, Borger MA, et al. Stroke after cardiac surgery: a risk factor analysis of 16,184 consecutive adult patients. Ann Thorac Surg. 2003;75(2):472-8. doi:10.1016/s0003-4975(02)04395-9

Martin WR, Hashimoto SA. Stroke in coronary bypass surgery. Can J Neurol Sci. 1982;9(1):21-6.

Coffey CE, Massey EW, Roberts KB, et al. Natural history of cerebral complications of coronary artery bypass graft surgery. Neurology. 1983;33(11):1416-21.

Breuer AC, Furlan AJ, Hanson MR, et al. Central nervous system complications of coronary artery bypass graft surgery: prospective analysis of 421 patients. Stroke. 1983;14(5):682-7. doi:10.1161/01.str.14.5.682

Junod FL, Harlan BJ, Payne J, et al. Preoperative risk assessment in cardiac surgery: comparison of predicted and observed results. Ann Thorac Surg. 1987;43(1):59-64. doi:10.1016/s0003-4975(10)61058-2

Liaño F, Pascual J. Epidemiology of acute renal failure: a prospective, multicenter, community-based study. Kidney Int. 1996;50(3):811-8. doi:10.1038/ki.1996.379

Refaat H, Saad H, Sabry A. The impact of perioperative urea and creatinine levels on the outcomes of cardiac surgery patients. J Cardiovasc Surg. 2016;57(5):716-22.

Wang Z, Jiang Z, Xiong W, et al. The relationship between inflammatory markers and postoperative complications in patients undergoing cardiac surgery. Cardiovasc Surg. 2018;26(3):194-200. doi:10.1177/0967210918762253

Blood urea nitrogen to creatinine ratio in hypovolemia assessment post major surgeries: a cross-sectional study. Egypt J Intern Med. 2021;33(2):410-21. doi:10.1186/s43066-021-00077-2

Shlipak MG, Phillips CO, DiCapua P, et al. Blood urea nitrogen as a risk factor in heart surgery. Front Cardiovasc Med. 2021;8:2041-3.

Urea level as an independent predictor of mortality in severe aortic stenosis patients. PLoS One. 2021;16(6). doi:10.1371/journal.pone.0245563

Blood urea nitrogen for predicting cardiovascular disease risks in the elderly. Front Cardiovasc Med. 2022;9:2318. doi:10.3389/fcvm.2022.1085984

Kidney Disease Improving Global Outcomes (KDIGO) AKI guideline. Kidney Int. 2012;2(Suppl 1):1-138.

Hoste EA, Bagshaw SM, Bellomo R, et al. Epidemiology of AKI in critically ill patients: the AKI-EPI study. Intensive Care Med. 2015;41(8):1411-23. doi:10.1007/s00134-015-3934-7

Ishani A, Xue JL, Himmelfarb J, et al. Acute kidney injury increases risk of ESRD among elderly. J Am Soc Nephrol. 2009;20(1):223-8. doi:10.1681/ASN.2007080837

Zarbock A, Gomez H, Kellum JA. Sepsis-induced AKI revisited: pathophysiology, prevention and future therapies. Curr Opin Crit Care. 2014;20(6):588-95. doi:10.1097/MCC.0000000000000153

Murugan R, Kellum JA. Acute kidney injury: prognosis. Nat Rev Nephrol. 2011;7(4):209-17. doi:10.1038/nrneph.2011.13

Coca SG, Yusuf B, Shlipak MG, Garg AX, Parikh CR. Long-term risk of mortality and other adverse outcomes after AKI: a systematic review. Am J Kidney Dis. 2009;53(6):961-73. doi:10.1053/j.ajkd.2008.11.034

Ostermann M, Joannidis M. AKI 2016: diagnosis and workup. Crit Care. 2016;20(1):299. doi:10.1186/s13054-016-1445-7

Gaudry S, Hajage D, Martin-Lefevre L, et al. Renal-replacement initiation strategies in ICU. N Engl J Med. 2016;375(2):122-33. doi:10.1056/NEJMoa1603017

Kellum JA, Bellomo R, Ronco C. AKI definition and classification. Kidney Int. 2015;89(2):145-53. doi:10.1038/ki.2015.236

Makris K, Spanou L. AKI: definition, pathophysiology and phenotypes. Clin Biochem Rev. 2016;37(2):85-98.

Thakar CV. Perioperative AKI. Adv Chronic Kidney Dis. 2013;20(1):67-75. doi:10.1053/j.ackd.2012.10.008

Ronco C, Bellomo R, Kellum JA. Acute kidney injury. Lancet. 2019;394(10212):1949-64. doi:10.1016/S0140-6736(19)32563-2

Downloads

Published

2025-01-09

How to Cite

Toprak, B., Kanat Toprak, Çise, & Cihan, H. (2025). Pre- and Postoperative Urea Levels in Open Heart Surgery: Assessment as a Risk Factor for Predicting Mortality - A Retrospective Analysis: Urea Levels and Mortality in Open Heart Surgery. Scientific Reports in Medicine, 1(3). https://doi.org/10.37609/srinmed.24

Issue

Section

Research Articles