Urine neutrophil gelatinase-associated lipocalin predicts outcome and renal failure in open and endovascular thoracic abdominal aortic aneurysm surgery

The role of Proenkephalin A 119-159 in the detection of acute kidney injury after open thoracoabdominal aortic repair

Background: Acute kidney injury (AKI) after open thoracoabdominal aortic aneurysm repairs (TAAA) is a common postoperative complication, associated with increased mortality and morbidity. Early detection and management of the kidney tissue damage remains of paramount importance. The aim of this prospectively conducted, observational trial was to evaluate the clinical applicability of Proenkephalin A 119-159 (penKid) for the detection of postoperative AKI. Patients and methods: Thirty-six patients, planned for elective open TAAA repairs from January 2019 to December 2022, were recruited in two German centres (University Hospital Aachen and Charité - University Hospital Berlin). Blood samples were collected pre-surgery (baseline), directly postoperatively and at 12, 24 and 48 hours after surgery. The penKid concentration in plasma was measured using the immunoluminometric sphingotest® assay kit and they were statistically tested for association with AKI and other clinical parameters. Results: Twenty-four patients (62%) developed moderate or severe AKI postoperatively (Stage 2 or 3 of the KDIGO classification) and they had a significantly increased risk for the development of acute respiratory distress syndrome (p=.023) or a fatal outcome (p=.035). Starting from the 12th hour after surgery, we found penKid correlating with AKI stage 2/3 (12 hour penKid mean in pmol/L: 93.9 vs. 43.1; c index .776, p=.0037) and renal replacement therapy (12 hour c index .779, p=.0035). Patients with multi-organ dysfunction syndrome had significantly increased penKid levels at all timepoints. Conclusions: We found penKid to be a promising biomarker for the early detection of postoperative AKI and in-hospital mortality after open TAAA repair, which may enable the early initiation of organ-protective strategies and reduction of further complications associated with AKI.

The NephroCheck bedside system for detecting stage 3 acute kidney injury after open thoracoabdominal aortic repair

Acute kidney injury (AKI) is a common complication after complex aortic procedures and it is associated with relevant mortality and morbidity. Biomarkers for early and specific AKI detection are lacking. The aim of this work is to investigate the reliability of the NephroCheck bedside system for diagnosing stage 3 AKI following open aortic surgery. In this prospective, multicenter, observational study,- https://clinicaltrials.gov/ct2/show/NCT04087161 -we included 45 patients undergoing open thoracoabdominal aortic repair. AKI risk (AKIRisk-Index) was calculated from urine samples at 5 timepoints: baseline, immediately postoperatively and at 12, 24, 48, and 72 h post-surgery. AKIs were classified according to the KDIGO criteria. Contributing factors were identified in univariable and multivariable logistic regression. Predictive ability was assessed with the area under the receiver operator curve (ROCAUC). Among 31 patients (68.8%) that developed AKIs, 21 (44.9%) developed stage-3 AKIs, which required dialysis. AKIs were correlated with increased in-hospital mortality (p = .006), respiratory complications (p < .001), sepsis (p < .001), and multi-organ dysfunction syndrome (p < .001). The AKIRisk-Index showed reliable diagnostic accuracy starting at 24 h post-surgery (ROCAUC: .8056, p = .001). In conclusion, starting at 24 h after open aortic repair, the NephroCheck system showed adequate diagnostic accuracy for detecting the patients at risk for stage 3 AKIs.

Machine learning model predicts the occurrence of acute kidney injury after open surgery for abdominal aortic aneurysm repair

OBJECTIVES

Abdominal aortic aneurysm is a pathological condition in which the abdominal aorta is dilated beyond 3.0 cm. The surgical options include open surgical repair (OSR) and endovascular aneurysm repair (EVAR). Prediction of acute kidney injury (AKI) after OSR is helpful for decision-making during the postoperative phase. To find a more efficient method for making a prediction, this study aims to perform tests on the efficacy of different machine learning models.

METHODS

Perioperative data of 80 OSR patients were retrospectively collected from January 2009 to December 2021 at Xiangya Hospital, Central South University. The vascular surgeon performed the surgical operation. Four commonly used machine learning classification models (logistic regression, linear kernel support vector machine, Gaussian kernel support vector machine, and random forest) were chosen to predict AKI. The efficacy of the models was validated by five-fold cross-validation.

RESULTS

AKI was identified in 33 patients. Five-fold cross-validation showed that among the 4 classification models, random forest was the most precise model for predicting AKI, with an area under the curve of 0.90±0.12.

CONCLUSIONS

Machine learning models can precisely predict AKI during early stages after surgery, which allows vascular surgeons to address complications earlier and may help improve the clinical outcomes of OSR.

Critical care management after open thoracoabdominal aortic aneurysm repair

Thoracoabdominal aortic aneurysm repair is technically demanding for the surgeon and physiologically demanding on the patient. As such, it requires diligent multidisciplinary perioperative care to maximize the likelihood of a successful outcome. In this article, we discuss key principles for managing patients after open thoracoabdominal aortic aneurysm repair, which we have learned over the course of performing more than 3500 of such procedures. These principles address patient handoff between the operating room and Intensive Care Unit, resuscitation, prevention and management of spinal cord deficits, and important neurological, respiratory, cardiovascular, renal, gastrointestinal, and hematological considerations. Understanding the expected postoperative course allows for earlier recognition of deviations from that course and increases the likelihood of successful rescue of patients from adverse outcomes. Achieving positive outcomes after thoracoabdominal aortic aneurysm repair requires attention to detail across the perioperative, intraoperative, and postoperative phases of care.

Increase of urinary TIMP-2 and IGFBP7 as potential predictor of acute kidney injury requiring renal replacement therapy and patients' outcome following complex endovascular and open thoracic abdominal aortic aneurysm surgery - a prospective observational study

Background: Acute kidney injury (AKI) as complication after open and endovascular repair of thoracoabdominal aortic aneurysm (TAAA) is one major predictor of mortality and postoperative complications. We evaluated tissue inhibitor of metalloproteinase 2 (TIMP-2) and insulin-like growth factor-binding protein 7 (IGFBP7) as combined early biomarker for AKI detection and predictor of patients' outcome. Patients and methods: Between 2014 and 2015, 52 patients have been enrolled in this observational study, of whom 29 (55.8%) underwent elective open repair and 23 (44.2%) endovascular repair. TIMP2 × IGFBP7 were measured until 48 hours after admission on intensive-care unit (ICU) and were analyzed regarding their predictive ability for AKI (defined according to the KDIGO criteria) requiring temporary renal replacement therapy (RRT) and 90-day mortality using ROC curves. Results: Mean patient age was 64.5 years (Min: 43, Max: 85), endovascular treated patients were older (p <0.0001). 40.4% (n = 21) developed AKI, and 21.2% (n = 11) required renal replacement therapy. In-hospital and total mortality rates were 7.7% (n = 4) and 9.6% (n = 5), respectively. At no time a significant difference in TIMP2 × IGFB7 levels between patients undergoing open or endovascular surgery was observed. The predictive quality of the TIMP2 × IGFBP7 value on ICU admission was sound regarding AKI requiring temporary renal replacement therapy (sensitivity: 55.56% [38.1-72.1%], specificity: 90.91% [58.7-99.8%] with an area under the curve [AUC]: 0.694 [0.543-0.820]). Mean follow-up was 13.2 months (Min: 2, Max: 20), regarding the 90-day mortality, the predictive property of the TIMP2 × IGFBP7 value was not sufficient (sensitivity: 80% [28.4-99.5%], specificity: 52.38% [36.4-68%], and AUC: 0.607 [0.454-0.746]). Conclusions: TIMP2 × IGFBP7 level measured 6-12 hrs postoperatively may be useful as an early detectable biomarker for AKI requiring temporary renal replacement therapy. It seems not suited to predict patients' outcome following complex thoracoabdominal aortic surgery, regardless if performed by open or endovascular repair.

Postoperatively increased bioactive adrenomedullin is related to adverse outcome after complex aortic surgery

Summary: Background: Open and endovascular thoracoabdominal aortic aneurysm repair is related to major complications and increased mortality rates. Up to now, specific biomarkers for adverse outcome are scarce, although routine usage of such biomarkers could enable an earlier and more appropriate treatment of complications during the postoperative course after complex aortic aneurysm repair. Patients and methods: In a prospective single-center study including 33 patients (48.5 % women, mean age 63.0 ± 16.2 years) undergoing elective complex open and endovascular aortic aneurysm repair, bioactive adrenomedullin (bio-ADM) was measured for 72 h perioperatively and an association with clinical endpoints, namely cardiogenic shock, death and the combined endpoint of the two aforementioned parameters was assessed. Furthermore, the association between bio-ADM and baseline characteristics and perioperative details including sepsis biomarkers score were assessed. Results: 51.5 % (n = 17) of patients developed postoperative acute kidney injury, 21.2 % (n = 7) pneumonia and 18.2 % (n = 6) sepsis. Cardiogenic shock was observed in 12.1 % (n = 4) patients. The in-hospital mortality rate was 18.2 % (n = 6), and 24.2 % (n = 8) of patients developed cardiogenic shock and/or died in hospital. A significant correlation of bio-ADM concentrations from all available time points was observed with leukocytes (r = 0.37, P < 0.0001), C-reactive protein (r = 0.56, P < 0.001) and serum creatinine levels (r = 0.52, P < 0.001). Increased bio-ADM at 12 h, 24 h, 48 h and 72 h after admission to ICU was associated with both, in-hospital death and cardiogenic shock, with an area under the curve for the combined endpoint of 0.598, 0.720, 0.880 and 0.967. Bio-ADM concentrations at 48 h and 72 h after admission to ICU were predictive for in-hospital death and cardiogenic shock (both P < 0.01). Conclusions: Bio-ADM may serve as postoperative biomarker for cardiogenic shock and death after complex open and endovascular aortic aneurysm repair, potentially enabling an earlier and by that more adequate treatment of adverse outcome after major surgery.

SLPI - a Biomarker of Acute Kidney Injury after Open and Endovascular Thoracoabdominal Aortic Aneurysm (TAAA) Repair

Acute kidney injury (AKI) is a relevant complication following thoracoabdominal aortic aneurysm repair (TAAA). Biomarkers, such as secretory leucocyte peptidase inhibitor (SLPI), may enable a more accurate diagnosis. In this study, we tested if SLPI measured in serum is an appropriate biomarker of AKI after TAAA repair. In a prospective observational single-center study including 33 patients (51.5% women, mean age 63.0 ± 16.2 years) undergoing open and endovascular aortic aneurysm repair in 2017, SLPI was measured peri-operatively (until 72 h after surgery). After surgery, the postoperative complications AKI, as defined according to the KDIGO diagnostic criteria, sepsis, death, MACE (major cardiovascular events) and, pneumonia were assessed. In a subgroup analysis, patients with preexisting kidney disease were excluded. Of 33 patients, 51.5% (n = 17) of patients developed AKI. Twelve hours after admission to the intensive care unit (ICU), SLPI serum levels were significantly increased in patients who developed AKI. Multivariable logistic regression revealed a significant association between SLPI 12 hours after admission to ICU and AKI (P = 0.0181, OR = 1.055, 95% CI = 1.009-1.103). The sensitivity of SLPI for AKI prediction was 76.47% (95% CI = 50.1-93.2) and the specificity was 87.5% (95% CI = 61.7-98.4) with an AUC = 0.838 (95% CI = 0.7-0.976) for an optimal cut-off 70.03 ng/ml 12 hours after surgery. In patients without pre-existing impaired renal function, an improved diagnostic quality of SLPI for AKI was observed (Sensitivities of 45.45-91.67%, Specificities of 77.7-100%, AUC = 0.716-0.932). There was no association between perioperative SLPI and the incidence of sepsis, death, MACE (major cardiovascular events), pneumonia. This study suggests that SLPI might be a post-operative biomarker of AKI after TAAA repair, with a superior diagnostic accuracy for patients without preexisting impaired renal function.