Impact of Acute Kidney Injury on Early to Long-Term Outcomes in Patients Who Underwent Surgery for Type A Acute Aortic Dissection

Long-term outcomes of treatment with different stent grafts in acute DeBakey type I aortic dissection

BACKGROUND

We developed an integrated triple-branched stent to treat acute DeBakey type I aortic dissection (AD) and modified it to enhance its adaptability. However, whether the patients treated by the modified stent would achieve better long-term prognosis is unknown.

METHODS

This study enrolled 147 patients with acute DeBakey type I AD. The original integrated triple-branched stents were used in 57 patients (Group A) between July 2012 and August 2013, and the modified stents in 90 patients (Group B) between September 2013 and March 2015. Clinical characteristics, surgical data, postoperative complications, mortality, and follow-up data of the two groups were analyzed.

RESULTS

The two groups presented comparable early death rates (Group A = 7.0%, Group B = 5.9%; p = .719). The incidence of postoperative acute kidney injury (AKI) was lower in Group B (10.0%) versus Group A (24.6%) (p = .018). Compared with the original integrated triple-branched stent graft, the modified stent could reduce the risk of early postoperative AKI (OR [95% CI] = 0.36 [0.14, 0.94]). Early endoleak rates were significantly lower in Group B (1.0%) compared to Group A (9.4%) (p = .004). During follow-up, there were five deaths in Group A (9.4%) and six deaths in Group B (7.2%) (p = .646). Chronic kidney injury (7.5% vs. 3.6%; p = .311), delayed endoleak (11.3% vs. 4.8%; p = .157), and late reinterventions (7.5% vs. 2.4%; p = .155) in the two groups were similar.

CONCLUSIONS

In patients with acute DeBakey type I AD, the modified stent showed feasible and safe treatment outcomes and reduced early endoleak rates. However, the long-term effects were similar to the original treatment.

Acute Kidney Injury After Acute Repair of Type A Aortic Dissection

BACKGROUND

The aim of this study was to examine the incidence, risk factors, and outcomes of patients with acute kidney injury (AKI) after surgery for acute type A aortic dissection (ATAAD) using the Nordic Consortium for Acute Type A Aortic Dissection registry.

METHODS

Patients who underwent ATAAD surgery at 8 Nordic centers from 2005 to 2014 were analyzed for AKI according to the RIFLE criteria. Patients who died intraoperatively, those who had missing baseline or postoperative serum creatinine, and patients on preoperative renal replacement therapy were excluded.

RESULTS

AKI occurred in 382 of 941 patients (40.6%), and postoperative dialysis was required for 105 patients (11.0%). Renal malperfusion was present preoperatively in 42 patients (5.1%), of whom 69.0% developed postoperative AKI. In multivariable analysis patient-related predictors of AKI included age (per 10 years; odds ratio [OR], 1.30; 95% confidence interval [CI], 1.15-1.48), body mass index >30 kg/m² (OR, 2.16; 95% CI, 1.51-3.09), renal malperfusion (OR, 4.39; 95% CI, 2.23-9.07), and other malperfusion (OR, 2.10; 95% CI, 1.55-2.86). Perioperative predictors were cardiopulmonary bypass time (per 10 minutes; OR, 1.04; 95% CI, 1.02-1.07) and red blood cell transfusion (OR per transfused unit, 1.08; 95% CI, 1.06-1.10). Rates of 30-day mortality were 17.0% in the AKI group compared with 6.6% in the non-AKI group (P < .001). In 30-day survivors AKI was an independent predictor of long-term mortality (hazard ratio, 1.86; 95% CI; 1.24-2.79).

CONCLUSIONS

AKI is a common complication after surgery for ATAAD and independently predicts adverse long-term outcome. Of note one-third of patients presenting with renal malperfusion did not develop postoperative AKI, possibly because of restoration of renal blood flow with surgical repair. Mortality risk persists beyond the perioperative period, indicating that close clinical follow-up of these patients is required.

Acute Kidney Injury in Asia: Disease Burden

Acute kidney injury (AKI) is a common and critical clinical disorder with non-negligible morbidity and mortality and remains a large public health problem. Asia, as the world's largest and most populous continent, is crucial in eliminating unsatisfactory outcomes of AKI. The diversities in climate, customs, and economic status lead to various clinical features of AKI across Asia. In this review, we focus on the epidemiologic data and clinical features of AKI in different Asian countries and clinical settings, and we show the huge medical and economic burden of AKI in Asian countries. Drugs and sepsis are the most common etiologies for AKI, however, an adequate surveillance system has not been well established. There is significant undertreatment of AKI in many regions, and medical resources for renal replacement therapy are not universally available. Although substantial improvement has been achieved, health care for AKI still needs improvement, especially in developing regions.

Risk factors analysis of acute kidney injury following open thoracic aortic surgery in the patients with or without acute aortic syndrome: a retrospective study

Background

The acute kidney injury (AKI) remains a frequent complication following open thoracic aortic surgery (OTAS) and worsens the postoperative prognosis. It remains unclear that whether the predictors of AKI following OTAS are different in the patients with or without acute aortic syndrome (AAS).

Methods

Preoperative and intraoperative variables were compared between the patients with or without AKI, and were further analyzed for identifying the potential predictors of postoperative AKI. Subgroup analysis was conducted in the patients with or without AAS, respectively.

Results

AKI after OTAS occurred in 57.6% of the overall cohort, 70.1% of the patients with AAS and 46.7% of the patients without AAS. In the multivariate analysis, history of hypertension (OR 1.011, 95% CI: [1.001–1.022], p = 0.04), preoperative platelet (OR 0.995, 95% CI: [0.991–0.999], p = 0.006) and operation time (OR 1.572, 95% CI: [1.355–1.823], p < 0.001) were identified as independent predictors of postoperative AKI for the overall cohort; CPB time (OR 1.020, 95% CI: [1.009–1.031], p < 0.001) and preoperative LMR (OR 0.823, 95% CI: [0.701–0.966], p = 0.02) as independent predictors for the patients with AAS; age (OR 1.045, 95% CI: [1.015–1.076], p = 0.003), preoperative platelet (OR 0.993, 95% CI: [0.988–0.998], p = 0.04) and operation time (OR 1.496, 95% CI: [1.166–1.918], p = 0.002) as independent predictors for the patients without AAS.

Conclusions

The patients with AAS carry a higher risk for postoperative AKI compared with those without AAS. The predictive factors for postoperative AKI after OTAS are different for AAS- and non-AAS subgroups and operation time, CPB time and preoperative platelet are modifiable predictors of AKI.

Characteristics and outcomes of Stanford type A aortic dissection patients with severe post-operation hyperbilirubinemia: a retrospective cohort study

BACKGROUND

Hyperbilirubinemia is one of the common complications after cardiac surgery and is associated with increased mortality. However, to the best of our knowledge, the reports on clinical significance of postoperative severe hyperbilirubinemia in Stanford type A aortic dissection (AAD) patients were limited.

METHODS

Patients who underwent surgical treatment for AAD in our center between January 2015 and December 2018 were retrospectively screened. In-hospital mortality, long-term mortality, acute kidney injury (AKI), and the requirement of continuous renal replacement therapy (CRRT) were assessed as endpoints. Univariate and multivariate regression models were employed to identify the risk factors of these endpoints.

RESULTS

After screening, 271 patients were included in our present study. Of the included patients, 222 (81.9%) experienced postoperative AKI, and 50 (18.5%) received CRRT. The in-hospital mortality was 30.3%. The 1-year, 2-year, and 3-year cumulative mortality were 32.9, 33.9, and 35.3%, respectively. Multivariate Logistic regression analysis indicated that age (P < 0.033), AKI stage 3 (P < 0.001), the amount of blood transfusion after surgery (P = 0.019), mean arterial pressure (MAP) in the first postoperative day (P = 0.012), the use of extracorporeal membrane oxygenation (ECMO) (P = 0.02), and the peak total bilirubin (TB) concentration (P = 0.023) were independent risk factors of in-hospital mortality. The optimal cut-off value of peak TB on predicting in-hospital mortality was 121.2 μmol/L. Patients with post-operation TB ≥ 121 μmol/L was associated with worse long-term survival as well.

CONCLUSIONS

Severe post-operation hyperbilirubinemia is a common clinical situation in patients had AAD repair. In AAD patients with severe post-operation hyperbilirubinemia, older age, lower MAP, increased blood transfusion, stage 3 AKI, the use of ECMO, and the increased peak TB lead to increase in-hospital mortality.

Independent risk factors and the long-term outcomes for postoperative continuous renal replacement treatment in patients who underwent emergency surgery for type a acute aortic dissection

Objective

The study objective was to investigate the incidence and risk factors of continuous renal replacement therapy (CRRT) in patients undergoing emergency surgery for type A acute aortic dissection (TA-AAD) and evaluate the perioperative and long-term outcomes.

Methods

From January 2014 to December 2018, 712 consecutive patients were enrolled in the study. These patients were divided into two groups according to whether or not needed postoperative CRRT: the CRRT group vs the control group. Univariate analysis and binary logistic regression analysis were used to analyze the risk factors of CRRT. To avoid the selection bias and confounders, baseline characteristics were matched for propensity scores. Kaplan-Meier curves were generated to provide survival estimates at postoperative points in time.

Results

Before propensity score matching, univariate analysis showed that there were significant differences in age, preoperative hypertension, pericardial effusion, preoperative serum creatinine (sCr), intraoperative need for combined coronary artery bypass grafting (CABG) or mitral valve or tricuspid valve surgery, cardiopulmonary bypass (CPB) time, extracorporeal circulation assistant time, aortic cross-clamp time, drainage volume 24 h after surgery and ventilator time between two groups. All were higher in the CRRT group (P < 0.05). These risk factors were included in binary logistic regression. It showed that preoperative sCr and CPB time were independent risk factors for CRRT patients undergoing surgery for TA-AAD. And there were significant differences regarding 30-day mortality (P < 0.001) and long-term overall cumulative survival (P < 0.001) with up to a 6-year follow-up. After propensity scoring, 29 pairs (58 patients) were successfully matched. Among these patients, the analysis showed that CPB time was still significantly longer in the CRRT group (P = 0.004), and the 30-day mortality rate was also higher in this group (44.8% vs 10.3%; P = 0.003).

Conclusion

CRRT after TA-AAD is common and worsened short- and long- term mortality. The preoperative sCr and CPB time are independent risk factors for postoperative CRRT patients. Shorten the CPB time as much as possible is recommended to reduce the risk of CRRT after the operation.

Inflammatory biomarkers to predict adverse outcomes in postoperative patients with acute type A aortic dissection

Objectives. The present study aimed to evaluate prognostic value of inflammatory markers for in-hospital mortality and renal complication in patients undergoing surgery for acute type A aortic dissection (ATAAD). Design. Serum concentration of C-reactive protein, leukocyte counts, procalcitonin (PCT), tumor necrosis factor (TNF)-α, interleukin-2 receptor (IL-2R), IL-6 and IL-8 were measured on the day of admission to the hospital (T0) and on 1st (T1), 2nd (T2), and 7th (T3) day after surgery. Results. 328 patients were included. There were significant differences between survivor group and non-survivor group in PCT, IL-2R, and IL-6 (p = .001, p = .015, and p = .005). There were significant differences between patients with different AKI stage in PCT and IL-2R (p = .001, p < .001). The area under receiver operating characteristics (ROC) curve on 30-day death was 0.686 for PCT, 0.718 for IL-2R, 0.694 for IL-6 and 0.627 for IL-8. The area under ROC curve on stage III AKI was 0.852 for PCT, 0.749 for IL-2R, 0.626 for IL-8, and 0.636 for TNF-α. IL-2 > 1438 U/ml and IL-6 > 45.5 pg/ml were independently associated with 30-day mortality (p = .014 and p < .001). The area under ROC curve was 0.849 on score 2 (using 1 point for PCT > 4.58 ng/ml, 1 point for IL-2R > 1438 U/ml, 1 point for APACHE II score >15.5, and 1 point for IL-6 > 45.5 pg/ml). Conclusions. PCT and cytokines may be considered as predictors for adverse renal outcomes and mortality in patients with ATAAD patients after surgery. They are earlier than traditional biomarkers and combination of these biomarkers will improve the accuracy.

The Association Between Obesity and Risk of Acute Kidney Injury After Cardiac Surgery

OBJECTIVE

To determine the relationship between obesity and the risk of AKI after cardiac surgery (CS-AKI) in a cohort study.

METHODS

A total of 1,601 patients undergoing cardiac surgery were collected and their incidence of CS-AKI was recorded. They were divided into underweight, normal weight, overweight, and obese groups. Logistic regression was used to estimate the association between BMI (body mass index) and CS-AKI risk. Then, a meta-analysis of published cohort studies was conducted to confirm this result using PubMed and Embase databases.

RESULTS

A significant association was observed in this independent cohort after adjusting age, gender, hypertension and New York Heart Association classification (NYHA) class. Compared with normal BMI group (18.5 ≤ BMI < 24.0), the individuals with aberrant BMI level had an increased AKI risk (OR: 1.68, 95% CI: 1.01-2.78) for BMI < 18.5 group and (OR: 1.43, 95% CI: 0.96-2.15) for BMI ≥ 28.0. Interestingly, the U-shape curve showed the CS-AKI risk reduced with the increasing of BMI when BMI ≤ 24.0. As BMI increases with BMI > 24.0, the risk of developing CS-AKI increased significantly. In the confirmed meta-analysis, compared with normal weight, overweight group with cardiac surgery had higher AKI risk (OR: 1.28, 95% CI: 1.16-1.41, P_{heterogeneity} = 0.49). The similar association was found in obesity subgroup (OR: 1.79, 95% CI: 1.57-2.03, P_{heterogeneity} = 0.42).

CONCLUSION

In conclusion, the results suggested that abnormal BMI was a risk factor for CS-AKI independently.

Lower body ischaemic time is a risk factor for acute kidney injury after surgery for type A acute aortic dissection

OBJECTIVES

Postoperative acute kidney injury (AKI) is known as a risk factor for death after surgery for Stanford type A acute aortic dissection under hypothermic circulatory arrest. It may also adversely affect long-term survival. We searched for modifiable risk factors for postoperative AKI, focusing on lower body ischaemic time.

METHODS

We reviewed 191 patients undergoing surgical repair for Stanford type A acute aortic dissection. The distal anastomosis depended on excluding the primary tear location, resulting in ascending/hemiarch (n = 119), partial arch (n = 18) and total arch replacement (n = 54). We defined an increase in the serum creatinine level to ≧2 times the baseline level as AKI. The incidence of AKI was investigated with multivariate analysis of its risk factors.

RESULTS

Postoperative AKI was observed in 49 patients (26%), 31% of whom required renal replacement therapy. The overall hospital mortality rate was 8.5%. Postoperative AKI, preoperative shock and organ malperfusion were predictors of hospital death. Multivariate stepwise logistic regression analysis identified age, body mass index, preoperative chronic kidney disease and lower body ischaemic time as risk factors for postoperative AKI.

CONCLUSIONS

Although surgical repair for Stanford type A acute aortic dissection showed favourable results, the incidence of postoperative AKI is still high, closely associated with hospital death. Lower body ischaemic time should be recognized specifically as a modifiable surgical risk factor for postoperative AKI.

Prediction Efficiency of Postoperative Acute Kidney Injury in Acute Stanford Type A Aortic Dissection Patients with Renal Resistive Index and Semiquantitative Color Doppler

Objectives

This study is aimed to evaluate the efficiency in early prediction of postoperative persistent acute kidney injury (PAKI) after surgery in acute Stanford type A aortic dissection (AAAD) patients by using Doppler renal resistive index (RRI) and semiquantitative color (SQC) Doppler grade, respectively.

Methods

84 AAAD patients received Sun's surgical management, and 67 patients were enrolled. RRI and SQC Doppler grade were evaluated by ultrasonography, respectively, at 6 hours after surgery. Serum creatinine (sCr) was recorded before operation and at 24 hours, 48 hours, and 72 hours after operation. AKI grade was evaluated according to the classifications of the Acute Kidney Injury Network (AKIN). PAKI is defined as persistent oliguria and/or sCr elevation after 3 days. RRI and SQC Doppler grade were compared, respectively, between the PAKI and non-PAKI groups. Potential predictors were first tested by univariate logistic regression analysis, and a multivariate model was identified to determine the independent predictive ability of RRI and SQC Doppler grade for the PAKI. Receiver operating characteristic (ROC) analysis was performed to compare the diagnostic accuracy between RRI and SQC Doppler grade in early prediction of PAKI by using AKIN classifications as the reference standard.

Results

Of a total of 67 patients enrolled during the study period, 21 (31.3%) patients suffered from PAKI and 8 (11.9%) patients required dialysis. There are significant differences in RRI (0.80 ± 0.09 vs. 0.70 ± 0.05, P=0.002) and SQC Doppler grade (x²=12.193, P=0.007) between the 2 groups with and without PAKI. Univariate analysis showed that RRI, SQC Doppler grade, length of stay in ICU, time of CPB, and length of stay in hospital were significant predictors of PAKI. RRI and the SQC Doppler grade remained independent predictors of PAKI. Area under the curve (AUC) of RRI was 0.855 (95% CI, 0.74–0.96) with cutoff value 0.725 (sensitivity 90.9% and specificity 71.1%), AUC of SQC Doppler grade was 0.642 (95% CI, 0.49–0.79) with cutoff value grade 2 (sensitivity 50% and specificity 73.3%).

Conclusion

Both postoperative RRI and SQC Doppler grade are independent predictors for PAKI after surgery in AAAD patients. Both postoperative RRI and SQC Doppler grade can be obtained rapidly by bedside ultrasound, which is a good tool for early prediction for postoperative PAKI.

Preoperative platelet count, preoperative hemoglobin concentration and deep hypothermic circulatory arrest duration are risk factors for acute kidney injury after pulmonary endarterectomy: a retrospective cohort study

Background

Acute kidney injury (AKI) is a major postoperative morbidity of patients undergoing cardiac surgery and has a negative effect on prognosis. The kidney outcomes after pulmonary endarterectomy (PEA) have not yet been reported; However, several perioperative characteristics of PEA may induce postoperative AKI. The objective of our study was to identify the incidence and risk factors for postoperative AKI and its association with short-term outcomes.

Methods

This was a single-center, retrospective, observational, cohort study. Assessments of AKI diagnosis was executed based on the Kidney Disease Improving Global Outcomes (KDIGO) criteria.

Results

A total of 123 consecutive patients who underwent PEA between 2014 and 2018 were included.

The incidence of postoperative AKI was 45% in the study population. Stage 3 AKI was associated with worse short-term outcomes and 90-day mortality (p < 0.001, p = 0.002, respectively). The independent predictors of postoperative AKI were the preoperative platelet count (OR 0.992; 95%CI 0.984–0.999; P = 0.022), preoperative hemoglobin concentration (OR 0.969; 95%CI 0.946–0.993; P = 0.01) and deep hypothermic circulatory arrest (DHCA) time (OR 1.197; 95%CI 1.052–1.362; P = 0.006) in the multivariate analysis.

Conclusion

The incidence of postoperative AKI was relatively high after PEA compared with other types of cardiothoracic surgeries. The preoperative platelet count, preoperative hemoglobin concentration and DHCA duration were modifiable predictors of AKI, and patients may benefit from some low-risk, low-cost perioperative measures.

Moderate and deep hypothermic circulatory arrest has a comparable effect on acute kidney injury after total arch replacement with frozen elephant trunk procedure in type A aortic dissection

OBJECTIVES

The goal was to investigate the prevalence of acute kidney injury (AKI) after total arch replacement with frozen elephant trunk procedure, which was achieved by antegrade cerebral perfusion and moderate hypothermic circulatory arrest (MHCA) or deep hypothermic circulatory arrest (DHCA) among patients with type A aortic dissection.

METHODS

Overall, 627 adult type A aortic dissection patients who underwent total arch replacement with frozen elephant trunk from January 2013 until December 2016 at Fuwai Hospital were divided into the DHCA (14.1-20.0°C) and MHCA (20.1-28.0°C) groups. Postoperative AKI as the primary outcome was compared using propensity-matched scoring.

RESULTS

Overall, 340 (54.2%) and 287 (45.8%) patients underwent DHCA and MHCA, respectively. The overall incidence of AKI was 75.4%. Age [odds ratio (OR) 1.02, 95% confidence interval (CI) 1.00-1.04; P = 0.022], body mass index (OR 1.06, 95% CI 1.01-1.12; P = 0.016), cardiopulmonary bypass duration (OR 1.01, 95% CI 1.00-1.01; P = 0.003) and hypertension history (OR 1.76, 95% CI 1.14-2.70; P = 0.010) were identified as independent risk factors for AKI onset with multivariable analysis. Postoperative AKI was not significantly different between the DHCA and MHCA groups regardless of the overall or propensity-matched cohort (overall data: P = 0.17; propensity score data: P = 0.88). Patients with MHCA experienced higher rates of postoperative stroke after propensity score analysis (DHCA 0.9% vs MHCA 3.7%; P = 0.034).

CONCLUSIONS

MHCA was not superior to DHCA in decreasing postoperative AKI. Thus, MHCA should not definitively replace DHCA.

Contrast-Induced Kidney Nephropathy in Thoracic Endovascular Aortic Repair: A 2-Year Retrospective Study in 470 Patients

We identified changes in renal function in patients who underwent thoracic endovascular aortic repair (TEVAR) and the factors that may influence renal function. Information on 470 consecutive patients was collected. Kidney function and contrast volume were recorded. Unpaired t test, Spearman correlation, and logistic regression were used for statistical analysis. A Kaplan-Meier curve helped clarify our follow-up findings. Mean contrast volume was 90.5 ± 21.2 mL. The change in serum creatinine was significantly correlated with (1) preexisting renal pathology (P = .033) and (2) aortic dissection (AD) involving the renal arteries (P = .019). The change in serum urea nitrogen (ΔBUN) was only significantly correlated with AD involving the renal arteries (P = .0348). Contrast volume (P = .036, odds ratio = 1.010, 95% confidence interval: 1.001-1.019) was a risk factor for contrast-induced nephropathy (CIN) after TEVAR. Survival rates and renal failure rates among no CIN, CIN, and CIN-acute kidney injury groups at longest 27 months follow-up were significantly different. Creatinine and BUN were generally elevated post-TEVAR. Contrast-induced nephropathy post-TEVAR may correlate with renal comorbidities and renal artery involvement. Contrast volume is risk factor for CIN after TEVAR. More attention needs to be paid to patient renal function during follow-up.

Acute type A aortic dissection - a review

Acute type A aortic dissection (ATAAD) is still one of the most challenging diseases that cardiac surgeons encounter. This review is based on the current literature and includes the results from the Nordic Consortium for Acute Type-A Aortic Dissection (NORCAAD) database. It covers different aspects of ATAAD and concentrates on the outcome of surgical repair. The diagnosis is occasionally delayed, and ATAAD is usually lethal if prompt repair is not performed. The dynamic nature of the disease, the variation in presentation and clinical course, and the urgency of treatment require significant attentiveness. Many surgical techniques and perfusion strategies of varying complexity have been described, ranging from simple interposition graft to total arch replacement with frozen elephant trunk and valve-sparing root reconstruction. Although more complex techniques may provide long-term benefit in selected patients, they require significant surgical expertise and experience. Short-term survival is first priority so an expedited operation that fits in with the surgeon's level of expertise is in most cases appropriate.

Prognostic Role of Admission C-Reactive Protein Level as a Predictor of In-Hospital Mortality in Type-A Acute Aortic Dissection: A Meta-Analysis

BACKGROUND

Acute aortic dissection (AD) is a lethal vascular disease, accounting for over 90% cases of acute aortic syndrome. Despite advances in understanding associated risk factors, the long-term prognosis for AD patients is still poor. Several prognostic biomarkers have been used for AD as per the IRAD, such as older age (>70 years), onset of chest pain and hypotension, but they are not effective in all patients. Instead, C-reactive protein (CRP) is a consistent inflammatory marker. CRP levels are abnormally increased in AD. However, the prognostic value of serum CRP level in AD remains unclear.

OBJECTIVE

To perform a systematic review and meta-analysis (registration no CRD42017056205) to evaluate whether CRP is a biomarker associated with in-hospital mortality in type-A AD.

METHODS

PubMed, Web of Science, CNKI, SciELO, and EMBASE were searched for papers published from January 2000 to October 2017 for studies on the prognostic role of CRP at admission in type-A AD patients. Outcome data were extracted and pooled hazard ratios (HRs) were calculated.

RESULTS

18 (N = 2875 patients) studies met the inclusion criteria. Elevated CRP level was associated with a significantly increased risk of in-hospital mortality in patients with type-A AD (HR = 1.15, 95% CI: 1.06-1.25, p = 0.001). The pooled sensitivity of CRP in type-A AD patients was 77% (95% CI 69%-84%, p < 0.001), and the specificity was 72% (95% CI 66%-78%, p < 0.001).

CONCLUSION

Elevated CRP level is significantly associated with increased risks of in-hospital mortality in patients with type-A AD. CRP is a convenient prognostic factor in type-A AD patients.

Acute Kidney Injury after Cardiac Surgery: Risk Factors and Novel Biomarkers

Acute kidney injury (AKI) is a common and severe complication after cardiac surgery. Currently, a series of novel biomarkers have favored the assessment of AKI after cardiac surgery in addition to the conventional indicators. The biomartkers, such as urinary liver fatty acid binding protein (L-FABP), urinary neutrophil gelatinase-associated lipocalin (NGAL), serum L-FABP, heart-type FABP, kidney injury molecule 1 (KIM-1), and interleukin-18 were found to be significantly higher in patients who developed AKI after cardiac surgery than those who did not. Apart from urinary interleukin-18, the novel biomarkers have been recognized as reliable indicators for predicting the diagnosis, adverse outcome, and even mortality of AKI after cardiac surgery. The timing of the renal replacement therapy is a significant predictor relating to patients’ prognoses. In patients with AKI after cardiac surgery, renal replacement therapy should be performed as early as possible in order to achieve promising outcomes. In children, AKI after cardiac surgery can be managed with peritoneal dialysis. AKI after cardiac surgery has received extensive attention as it may increase early mortality and impact long-term survival of patients as well. The purpose of this article was to analyze the changes of the pertinent biomarkers, to explore the related risk factors leading to the occurrence of AKI after cardiac surgery, and to provide a basis for the clinical prevention and reduction of AKI.

Cardiopulmonary bypass time is an independent risk factor for acute kidney injury in emergent thoracic aortic surgery: a retrospective cohort study

BACKGROUND

Thoracic aortic surgery and cardiopulmonary bypass are both associated with development of postoperative acute kidney injury. In this study, we undertook to investigate the relationship between cardiopulmonary bypass time and postoperative acute kidney injury in patients undergoing thoracic aortic surgery for acute DeBakey Type I aortic dissection.

METHODS

All patients receiving thoracic aortic surgery for acute DeBakey Type I aortic dissection in Beijing Anzhen hospital from December 2015 to April 2017 were included. Cardiopulmonary bypass time was recorded during surgery. Acute kidney injury was defined based on the Kidney Disease Improving Global Outcomes criteria. A total of 115 consecutive patients were eventually analyzed.

RESULTS

The overall incidence of acute kidney injury was 53.0% (n = 61). The average age was 47.8 ± 10.7 years; 74.8% were male. Mean cardiopulmonary bypass time was 211 ± 56 min. In-hospital mortality was 7.8%. Multivariate logistic regression revealed that cardiopulmonary bypass time was independently associated with the occurrence of postoperative acute kidney injury after adjust confounding factors (odds ratio = 1.171; 95% confidence interval: 1.002-1.368; P = 0.047).

CONCLUSIONS

Cardiopulmonary bypass time is independently associated with an increased hazard of acute kidney injury after thoracic aortic surgery for acute DeBakey Type I aortic dissection. Further understanding of the mechanism of this association is crucial to the design of preventative strategies.

Duplex Ultrasound Assessment and Outcomes of Renal Malperfusion Syndromes after Acute Aortic Dissection

BACKGROUND

We investigated the feasibility of renal duplex ultrasound in the identification of renal malperfusion in acute aortic dissection and evaluated whether intervention for renal malperfusion improved outcomes over best medical management alone.

METHODS

All patients with acute aortic dissections involving the renovisceral aorta who underwent a duplex ultrasound were included (2004-2016). We assessed duplex findings among patients who developed acute kidney injury (AKI; 50% increase in serum creatinine) and compared AKI, 30-day mortality, and overall survival among patients who underwent a procedure to treat malperfusion versus those who did not.

RESULTS

Of 37 patients with acute dissection involving the renovisceral aorta (73% were male, 59% had type B dissection, mean follow-up 4.6 ± 0.6 years), 70% developed AKI, 11% required dialysis, and 5% developed permanent dialysis dependence. AKI was correlated with higher peak creatinine levels (4.2 vs. 2.2 mg/dL, P < 0.001), although 30-day mortality and overall survival were similar (both, P ≥ 0.24). Progression to AKI was associated with significantly lower end-diastolic velocity (EDV) measurements on renal duplex (17 vs. 27 cm/sec, P = 0.03); an EDV threshold of 23 cm/sec had a positive predictive value of 85% for AKI. Operative intervention (n = 10) was associated with lower follow-up creatinine (0.9 vs. 2.1 mg/dL, P = 0.002), although there was no difference in progression to dialysis dependence, 30-day mortality, or overall survival (all, P ≥ 0.34).

CONCLUSIONS

Patients who developed AKI demonstrated characteristic renal duplex ultrasound findings with lower EDV measurements in the distal renal arteries bilaterally. Performing a renal malperfusion procedure was associated with normalization of postoperative creatinine without affecting 30-day mortality or overall survival.

Long-term risk of adverse outcomes after acute kidney injury: a systematic review and meta-analysis of cohort studies using consensus definitions of exposure

Reliable estimates of the long-term outcomes of acute kidney injury (AKI) are needed to inform clinical practice and guide allocation of health care resources. This systematic review and meta-analysis aimed to quantify the association between AKI and chronic kidney disease (CKD), end-stage kidney disease (ESKD), and death. Systematic searches were performed through EMBASE, MEDLINE, and grey literature sources to identify cohort studies in hospitalized adults that used standardized definitions for AKI, included a non-exposed comparator, and followed patients for at least 1 year. Risk of bias was assessed by the Newcastle-Ottawa Scale. Random effects meta-analyses were performed to pool risk estimates; subgroup, sensitivity, and meta-regression analyses were used to investigate heterogeneity. Of 4973 citations, 82 studies (comprising 2,017,437 participants) were eligible for inclusion. Common sources of bias included incomplete reporting of outcome data, missing biochemical values, and inadequate adjustment for confounders. Individuals with AKI were at increased risk of new or progressive CKD (HR 2.67, 95% CI 1.99-3.58; 17.76 versus 7.59 cases per 100 person-years), ESKD (HR 4.81, 95% CI 3.04-7.62; 0.47 versus 0.08 cases per 100 person-years), and death (HR 1.80, 95% CI 1.61-2.02; 13.19 versus 7.26 deaths per 100 person-years). A gradient of risk across increasing AKI stages was demonstrated for all outcomes. For mortality, the magnitude of risk was also modified by clinical setting, baseline kidney function, diabetes, and coronary heart disease. These findings establish the poor long-term outcomes of AKI while highlighting the importance of injury severity and clinical setting in the estimation of risk.

Impact of preoperative elevated serum creatinine on long-term outcome of patients undergoing aortic repair with Stanford A dissection: a retrospective matched pair analysis

BACKGROUND

The aim of the present study was to determine whether raised preoperative serum creatinine affected the long-term outcome in patients undergoing surgical aortic repair for Stanford A acute aortic dissection (AAD).

METHODS

A total of 240 patients diagnosed with Stanford A AAD underwent surgical repair from January 2006 to April 2015. A propensity score matching was applied, resulting in 73 pairs consisting of one group with normal and one group with preoperative elevated creatinine levels. The cohorts were well balanced for baseline and preoperative clinical characteristics. Both groups were compared regarding their early postoperative variables, as well as estimated survival with up to 9-year follow up. Also, the impact of acute postoperative kidney injury and its severity on long-term survival was analyzed.

RESULTS

The proportion of patients suffering Stanford A AAD with raised creatinine levels was 31.3% ( n = 75). After propensity matching, there were no statistically significant differences regarding demographics, comorbidities, preoperative baseline and clinical characteristics. Postoperatively matched patients with elevated creatinine had longer intensive care unit ( p < 0.001) and total hospital stay ( p = 0.002), prolonged intubation times ( p = 0.014), higher need for hemofiltration ( p < 0.001), higher incidence of temporary neurological disorders ( p = 0.16), infection ( p = 0.005), and trend toward higher incidence of sepsis ( p = 0.097). However, there were no significant differences regarding 30-day mortality (20.5% versus 20.5%, p = 1.000) and long-term overall survival. Further, neither the incidence nor the different stages of acute kidney injury according to the Acute Kidney Injury Network showed any statistically significant differences in terms of long-term survival for both groups [log rank p = 0.636, Breslow (generalized Wilcoxon) p = 0.470, Tarone-Ware p = 0.558].

CONCLUSIONS

Patients with elevated creatinine levels undergoing surgical repair for Stanford A AAD demonstrate higher rate of early postoperative complications. However, 30-day mortality and long-term survival in this patient cohort is not significantly impaired.

The Relationship Between Renal Artery Involvement in Stanford B-Type Aortic Dissection and the Short-Term Prognosis: A Single-Centre Retrospective Cohort Study

BACKGROUND

Renal artery involvement has not received sufficient attention despite the fact that aortic computed tomography angiography (CTA) examinations of Stanford B-type aortic dissection patients usually show renal artery involvement [3]. To study the influence of renal artery involvement on aortic dissection, we performed a retrospective study on acute Stanford B-type aortic dissection patients with or without renal artery involvement to investigate its effect on the prognosis of aortic dissection.

METHODS

A total of 221 patients with acute Stanford-B type aortic dissection between January 2012 and January 2014 were enrolled. The patients were divided into a renal artery involvement group and a non-renal artery involvement group based on aortic computed tomography angiography (CTA) results. The clinical data of the two groups were compared. Univariate analyses and multiple logistic regression analyses were performed to determine risk factors related to in-hospital mortality. The effect of renal artery involvement on the prognosis of Stanford B-type aortic dissection patients was analysed.

RESULTS

Among the 221 patients with acute Stanford type-B aortic dissection, 100 patients (45.2%) exhibited renal artery involvement. The percentage of patients with a past history of hypertension in the renal artery involvement group was significantly higher than that in the non-renal artery involvement group (84.0% vs. 74.8%, p=0.025). The estimated glomerular filtration rate (eGFR), creatinine level, and urea nitrogen level at admission were not significantly different between the renal artery involvement group and the non-renal artery involvement group. The in-hospital mortality rate in the renal artery involvement group was higher than that in the non-renal artery involvement group; the difference in the percentage of in-hospital mortality between these two groups was statistically significant (12.0% vs. 4.1%, p<0.05). The results of multiple logistic regression analysis showed that renal artery involvement was a risk factor for in-hospital mortality in acute Stanford B-type aortic dissection patients (odds ratio (OR)=3.536 (1.127∼11.095)). In the renal artery involvement group, the in-hospital mortality rate in the conservative treatment group was significantly higher than that in the interventional treatment group (30.8% vs. 5.4%, p=0.001).

CONCLUSIONS

Although renal artery involvement was not associated with short-term renal function damage, it was a risk factor for in-hospital mortality after acute Stanford B-type aortic dissection.

Incidence and risk factors of recurrent pain in acute aortic dissection and in-hospital mortality

BACKGROUND

We investigated the prevalence of recurrent pain and its relationship with in-hospital mortality in acute aortic dissection (AAD).

PATIENTS AND METHODS

Between 2011 and 2016, 234 AAD patients were selected. Recurrent pain was defined as a mean of VAS > 3, within 48 hours following hospital admission or before emergency operation. Patients with and without recurrent pain were divided into group I and group II, respectively into type A AAD and type B AAD patients. Our primary outcome was in-hospital mortality.

RESULTS

The incidence of recurrent pain was 24.4 % in AAD patients. Incidence of recurrent pain was higher in type A AAD patients than type B AAD patients (48.9 vs. 9.6 %). Overall in-hospital mortality was 25.6 %. Type A AAD had a higher in-hospital mortality than type B AAD patients (47.7 vs. 12.3 %). Group I had significantly higher in-hospital mortality than group II (type A: 79.1 vs. 17.8 %; type B: 57.1 vs. 7.6 %, all P < 0.001), as was the case with medical managed patients (type A: 72.1 vs. 13.3 %; type B: 35.7 vs. 2.3 %, all P < 0.001). Logistic regression analysis showed that use of one drug alone and waist pain were predictive factors for recurrent pain in type A AAD and type A AAD patients, respectively (OR 3.686, 95 % CI: 1.103~12.316, P = 0.034 and OR 14.010, 95 % CI: 2.481~79.103, P = 0.003). Recurrent pains were the risk factors (type A: OR 11.096, 95 % CI: 3.057~40.280, P < 0.001; type B: OR 14.412, 95 % CI: 3.662~56.723, P < 0.001), while invasive interventions were protective (type A: OR 0.133, 95 % CI: 0.035~0.507, P < 0.001; type B: OR 0.334, 95 % CI: 0.120~0.929, P = 0.036) for in-hospital mortality in AAD patients.

CONCLUSIONS

Approximately one-fourth of AAD patients presented with recurrent pains, which might increase in-hospital mortality. Thus, interventional strategies at early stages are important.

Independent risk factors for postoperative AKI and the impact of the AKI on 30-day postoperative outcomes in patients with type A acute aortic dissection: an updated meta-analysis and meta-regression

Background

This meta-analysis aims to investigate the effects of postoperative acute kidney injury (AKI) on 30-day postoperative outcomes and the independent risk factors for postoperative AKI in patients with type A acute aortic dissection (TAAD).

Methods

Relevant reports published between January 1, 2011 and May 31, 2017 were searched in multiple electronic literature databases. A total of seven eligible articles were included in the meta-analysis.

Results

Postoperative AKI was associated with 249% increase in 30-day postoperative mortality [odds ratio (OR): 3.49; 95% confidence interval (CI): 2.17-5.59; P<0.0001]. Subgroup analysis revealed that patients with stage II/III AKI showed 445% increase in 30-day postoperative mortality compared with the control group (OR: 5.45; 95% CI: 2.87-10.36; P<0.0001). Postoperative AKI was also associated with 143%, 432%, and 126% increase in the incidences of 30-day postoperative stroke, bleeding, and respiratory complications, respectively. Notably, high body mass index (BMI), advanced age, and perioperative sepsis were independent risk factors for postoperative AKI in patients with TAAD.

Conclusions

This meta-analysis firstly provided clinical evidence showing the adverse effects of postoperative AKI on 30-day postoperative outcomes in patients with TAAD and identified high BMI, advanced age, and perioperative sepsis as the independent risk factors for postoperative AKI. These findings suggest that preventive or therapeutic methods to effectively manage postoperative AKI may improve 30-day postoperative outcomes in patients with TAAD.

Early Detection of Postoperative Acute Kidney Injury in Acute Stanford Type A Aortic Dissection With Doppler Renal Resistive Index

OBJECTIVES

This study aimed to evaluate the early efficiency of Doppler renal resistive index (DRRI) in prediction of acute kidney injury (AKI) after surgery in acute Stanford Type A aortic dissection (AAAD) patients.

METHODS

Sixty-one AAAD patients who planned to receive Sun's surgical management were prospectively enrolled. The DRRI was measured by ultrasonography Doppler on the day before surgery (DRRI_pre ), on admission to the intensive care unit (DRRI_T0 ), 6 hours after surgery (DRRI_T6 ), 24 hours after surgery (DRRI_T24 ), and 48 hours after surgery (DRRI_T48 ). The maximum DRRI value (DRRI_max ) was recorded. The AKI was evaluated according to the classifications of the Acute Kidney Injury Network. The DRRI and serum creatinine (sCr) were compared between the pre- and postoperative time stations, as well as between the AKI and no-AKI groups.

RESULTS

Thirty-nine (63.9%) patients suffered from AKI, and 12 (19.6%) patients received dialysis. No significant difference was found in DRRI_pre (0.63 ± 0.04 versus 0.65 ± 0.06, P = .059) and sCr_pre (84.13 ± 23.77 versus 94.29 ± 51.11, P = .383) between the two groups with and without AKI. Both the DRRI and sCr increased significantly after surgery in the AKI groups (P < .001). However, the DRRI reached its maximum 6 hours after surgery, whereas the sCr reached its maximum after 24 hours. Both the DRRI and sCr improved 48 hours after surgery. The area under the receiver operating characteristic curve for DRRI_max (0.864, 95% confidence interval: 0.770-0.957) and DRRI_T6 (0.861, 95% confidence interval: 0.766-0.957) was larger than the other three DRRIs measured at different time points. The cutoff value of DRRI_max was 0.71, a sensitivity of 76.9% and specificity of 95.5%.

CONCLUSIONS

Postoperative DRRI predicts the AKI earlier than sCr after AAAD surgery. The best time to detect DRRI was 6 hours after surgery.

Significance of the thrombo-inflammatory status-based novel prognostic score as a useful predictor for in-hospital mortality of patients with type B acute aortic dissection

Background

Inflammation and thrombosis are associated with development and progression of acute aortic dissection (AAD). The aim of this study was to assess the prognostic significance of Simplified Thrombo-Inflammatory Prognostic Score (sTIPS), in patients with early phase type B AAD.

Methods

We retrospectively reviewed 491 patients with type B AAD between November 2012 and September 2015. sTIPS was calculated from the white blood cell count (WBC) and mean platelet volume to platelet count (MPV/PC) ratio, at the time of admission. Patients with both, WBC > 10 (10⁹/L) and MPV/PC ratio > 7.5 (10²fL/10⁹L^-1) were assigned a score of 2, while patients with high levels of either one or none of the above markers, were assigned scores of 1 and 0 respectively. Multivariable Cox regression analyses were used to investigate the associations between the score and hospital survival.

Results

Of the 491 type B AAD patients included in this analysis, 24 patients (4.9%) died during hospitalization. Kaplan-Meier analysis revealed that the cumulative mortality was significantly higher in patients with higher sTIPS (P = 0.001). Multivariable Cox regression analysis further indicated that higher sTIPS was a strong predictor of in-hospital mortality after eliminating all confounding factors (sTIPS 2: hazard ratio 4.704, 95%; confidence interval [CI] 1.184-18.685; P = 0.028; sTIPS 1: hazard ratio 1.918, 95%; CI 1.134-3.537; P = 0.045).

Conclusions

sTIPS at admission was a useful tool for stratifying the risk in type B AAD patients, for outcomes such as in-hospital mortality in the early phase.

Association of preoperative hypoalbuminemia with postoperative acute kidney injury in patients undergoing brain tumor surgery: a retrospective study

OBJECTIVE Hypoalbuminemia is known to be independently associated with postoperative acute kidney injury (AKI). However, little is known about the association between the preoperative serum albumin level and postoperative AKI in patients undergoing brain tumor surgery. The authors investigated the incidence of AKI, impact of preoperative serum albumin level on postoperative AKI, and death in patients undergoing brain tumor surgery. METHODS The authors retrospectively reviewed the electronic medical records and laboratory results of 2363 patients who underwent brain tumor surgery between January 2008 and December 2014. Postoperative AKI was defined according to Kidney Disease: Improving Global Outcomes Definition and Staging (KDIGO). Multivariate logistic regression analysis was used to identify demographic, preoperative laboratory, and intraoperative factors associated with AKI development. Cox proportional hazards models were used to investigate the adjusted odds ratio and hazard ratio for the association between preoperative serum albumin level and outcome variables. RESULTS The incidence of AKI was 1.8% (n = 43) using KDIGO criteria. The incidence of AKI was higher in patients with a preoperative serum albumin level < 3.8 g/dl (3.5%) than in those with a preoperative serum albumin level ≥ 3.8 g/dl (1.2%, p < 0.001). The overall mortality was also higher in the former than in the latter group (5.0% vs 1.8%, p < 0.001). After inverse probability of treatment-weighting adjustment, a preoperative serum albumin level < 3.8 g/dl was also found to be associated with postoperative AKI (OR 1.981, 95% CI 1.022-3.841; p = 0.043) and death (HR 2.726, 95% CI 1.522-4.880; p = 0.001). CONCLUSIONS The authors' results demonstrated that a preoperative serum albumin level of < 3.8 g/dl was independently associated with AKI and mortality in patients undergoing brain tumor surgery.

Long-Term Survival in Patients With Acute Kidney Injury After Acute Type A Aortic Dissection Repair

BACKGROUND

Although acute kidney injury (AKI) is known as a serious complication after operation for acute type A aortic dissection (AAAD), the long-term impact of AKI remains unclear. The aim of the present study is to investigate the long-term survival in patients with AKI after operation for AAAD.

METHODS

This study included 403 patients who underwent operation for AAAD from 1990 to 2011 at Jichi Medical University, Saitama Medical Center. Postoperative AKI was identified according to the Kidney Disease Improving Global Outcomes criteria. Kaplan-Meier survival analysis and Cox proportional hazards regression were modeled to analyze the association between the AKI stage and postoperative long-term survival.

RESULTS

Of 403 patients, 181 (44.9%) experienced postoperative AKI. Kaplan-Meier estimates for long-term survival were significantly different among patients without AKI and patients with stage 1, 2, and 3 AKI (p < 0.001). Hazard ratios of long-term survival for patients with stages 1, 2, and 3 AKI compared with patients without AKI were 1.38 (95% confidence interval [CI]: 0.84 to 2.26), 1.82 (95% CI: 0.95 to 3.51), and 3.79 (95% CI: 1.95 to 7.37), respectively. More patients with AKI died because of cardiovascular disease after discharge than patients without AKI (1.8% versus 6.0%, p = 0.03).

CONCLUSIONS

Stage 3 AKI is significantly associated with lower long-term survival after operation for AAAD. Patient follow-up after discharge that focuses on cardiovascular issues may benefit patients who survive AKI after AAAD operation.

Long-term remote organ consequences following acute kidney injury

Acute kidney injury (AKI) has been a global health epidemic problem with soaring incidence, increased long-term risks for multiple comorbidities and mortality, as well as elevated medical costs. Despite the improvement of patient outcomes following the advancements in preventive and therapeutic strategies, the mortality rates among critically ill patients with AKI remain as high as 40–60 %. The distant organ injury, a direct consequence of deleterious systemic effects, following AKI is an important explanation for this phenomenon. To date, most evidence of remote organ injury in AKI is obtained from animal models. Whereas the observations in humans are from a limited number of participants in a relatively short follow-up period, or just focusing on the cytokine levels rather than clinical solid outcomes. The remote organ injury is caused with four underlying mechanisms: (1) “classical” pattern of acute uremic state; (2) inflammatory nature of the injured kidneys; (3) modulating effect of AKI of the underlying disease process; and (4) healthcare dilemma. While cytokines/chemokines, leukocyte extravasation, oxidative stress, and certain channel dysregulation are the pathways involving in the remote organ damage. In the current review, we summarized the data from experimental studies to clinical outcome studies in the field of organ crosstalk following AKI. Further, the long-term consequences of distant organ-system, including liver, heart, brain, lung, gut, bone, immune system, and malignancy following AKI with temporary dialysis were reviewed and discussed.