Role of ankle brachial index measured by simple automatic sphygmomanometers in predicting postoperative kidney function in patients undergoing major cardiac surgery

Introduction: Ankle-brachial pressure index is an objective, noninvasive test for predicting subclinical atherosclerotic diseases. We investigated the role of ankle-brachial pressure index measured with automated sphygmomanometer devices in the prediction of the development of acute kidney injury in patients undergoing major cardiac surgery. Methods: This single-centered, cross-sectional, and observational study was performed on 80 (66 males and 14 females, 58 +/- 10 years) patients undergone cardiac surgery. Complete anamnesis, laboratory tests, intravenous fluids, medications, blood products, and all perioperative procedures were recorded in all patients before the surgery. Two automated sphygmomanometer devices giving equivalent results were used for measuring Ankle-brachial pressure index. The data in the first two days after the surgery were used for analysis. The criteria of AKIN were used in the diagnosis of acute kidney injury. Results: Twenty-one (23%) patients developed acute kidney injury in the postoperative period. None of the patients needed renal replacement therapy or died. There was no significant difference between mean ankle-brachial pressure index levels of patients with and without acute kidney injury (1.04 +/- 0.17 and 1.06 +/- 0.19, respectively, p=0.554). The mean ankle-brachial pressure index was significantly lower in patients with perioperative complications that cause hemodynamic instability (1.07 +/- 0.14, 0.96 +/- 0.13, p=0.016). On the multivariate analysis model, only perioperative hemodynamic complication development was found to be related to postoperative acute kidney injury. Conclusion: Anklebrachial pressure index may have a role in predicting perioperative hemodynamic complications, which may cause acute kidney injury in patients undergoing major surgery. Simple automatic blood pressure devices can be used in daily practice for ankle-brachial pressure index measurement instead of complex and expensive doppler devices.