Effect of goal-directed therapy bundle based on PiCCO parameters to the prevention and treatment of acute kidney injury in patients after cardiopulmonary bypass cardiac operation: a prospective observational study

Abstract

To explore the effect of goal-directed therapy bundle based on pulse-indicated continuous cardiac output (PiCCO) parameters to the prevention and treatment of acute kidney injury (AKI) in patients after cardiopulmonary bypass cardiac operation. A prospective observational study was conducted. The adult patients with selective cardiopulmonary bypass cardiac operation admitted to the Third People's Hospital of Chengdu from December 2015 to January 2018 were enrolled. All patients were divided into two groups based on informed consent for PiCCO monitor at the time of admission to the intensive care unit (ICU): regular monitoring and treatment group (group A) and goal-directed therapy group based on PiCCO parameters (group B). In group A, the restrictive capacity management strategy was implemented to maintain the mean arterial pressure (MAP) > 65 mmHg (1 mmHg = 0.133 kPa) and the central venous pressure (CVP) between 8 mmHg and 10 mmHg. In group B, volume and hemodynamic status were optimized depending on PiCCO parameters to a goal of cardiac index (CI) > 41.68 mL×s-1×m-2, global end diastolic volume index (GEDVI) > 700 mL/m2 or intrathoracic blood volume index (ITBVI) > 850 mL/m2, extravascular lung water index (EVLWI) < 10 mL/kg, and MAP > 65 mmHg. Then the changes in hemodynamics and different prognosis of the patients in two groups were observed. Risk factors affecting the AKI were analyzed by Logistic regression. 171 cases were included, with 68 in group A and 103 in group B. There were no significant differences in gender, age, pre-operative scores by European system for cardiac operative risk evaluation (EuroScore), operation ways, operation time, cardiopulmonary bypass time, intraoperative dominant liquid equilibrium quantity, the use of intra-aortic balloon counterpulsation (IABP) during operation, and serum creatinine (SCr) level at the time of admission to ICU between the two groups. There were no significant differences in CVP within 24 hours after admission to ICU between the two groups. MAP in group B was significantly higher than that in group A at 8 hours and 16 hours after ICU admission (mmHg: 68.9±6.3 vs. 66.7±5.1, 69.0±4.9 vs. 67.0±5.3, both P < 0.05). Sequential organ failure assessment (SOFA) score in group B was significantly lower than that in group A at 24 hours after ICU admission (5.7±2.2 vs. 6.9±2.8, P < 0.05). Dominant liquid equilibrium quantity in group B was significant higher than that in group A at 24 hours after ICU admission (mL/kg: 7.1±6.2 vs. -0.1±8.2, P < 0.01), but there was no significant difference of that between groups at 48 hours and 72 hours after ICU admission. Compared with group A, incidence of combination with AKI during 72 hours after ICU admission was significantly decreased in group B [48.5% vs. 69.1%; odds ratio (OR) = 0.422, 95% confidence interval (95%CI) = 0.222-0.802, P < 0.05], and incidence of moderate to severe AKI was also significantly decreased in group B (19.4% vs. 35.3%; OR = 0.442, 95%CI = 0.220-0.887, P < 0.05). There was no significant difference in usage of continuous renal replacement therapy (CRRT) after ICU admission between both groups (group A was 4.4%, group B was 4.9%, P > 0.05). It was shown by correlation analysis that only MAP and CI at 8 hours after ICU admission were significantly negatively correlated with AKI (MAP and AKI: r = -0.697, P = 0.000; CI and AKI: r = -0.664, P = 0.000). It was shown by Logistic regressive analysis that the MAP and CI at 8 hours after ICU admission were independent risk factors that influence the incidence of AKI at 72 hours after ICU admission (MAP: OR = 0.736, 95%CI = 0.636-0.851, P = 0.000; CI: OR = 0.006, 95%CI = 0.001-0.063, P = 0.000). There were no significant differences in the duration of mechanical ventilation, the length of ICU stay, the post-operation complications (except AKI), 7-day and 28-day mortality between the two groups. Goal-directed therapy bundle based on PiCCO parameters reduced the incidence of AKI in patients after cardiopulmonary bypass cardiac operation and improved the severity of systemic disease. However, it did not reduce the duration of mechanical ventilation, length of ICU stay, the incidence of complications (except AKI), short-term mortality. The MAP and CI at 8 hours after ICU admission were independent risk factors that influence the incidence of AKI in patients after cardiopulmonary bypass cardiac operation.