Contemporary Experience with Paravisceral Aortic Aneurysm (PVAAA) Repair in a Tertiary Center

A Systematic Review of Renal Perfusion in Complex Abdominal Aortic Aneurysm Open Repair

INTRODUCTION

This systematic review aims to analyze the current literature regarding 30-day mortality and postoperative acute kidney disease (AKI) in complex abdominal aortic aneurysms (cAAAs), which included juxtarenal aortic aneurysm (JAA), suprarenal aortic aneurysm (SRAA), and type IV thoracoabdominal aortic aneurysm (TAAA) open surgery (OS), to evaluate the impact of renal perfusion on AKI and to try to define which is the best way to perform it.

METHODS

A literature search in PubMed and Cochrane Library was performed, and articles published from January 1986 to January 2024 reporting on JAA, SRAA, and TAAA type IV open surgery management were identified. Multicenter studies, single-center series, and case series with ≥10 patients were considered eligible. Comparisons of outcomes of patients who underwent OS for complex abdominal aortic aneurysms (cAAAs) with or without perfusion of the renal arteries were analyzed when available. The titles, abstracts, and full texts were evaluated by two authors independently. The primary outcomes included AKI and 30-day mortality rates. The new-onset dialysis rate was considered a secondary outcome.

RESULTS

A total of 295 articles were evaluated, and 21 were included, totaling 5708 patients treated for cAAAs with OS. The male patients totaled 4094 (71.7%), with a mean age of 70.35 ± 8.01 and a mean renal ischemia time of 32.14 ± 12.89 min. Data were collected and analyzed, at first in the entire cohort and then divided into two groups (no perfusion of the renal arteries-group A vs. selective perfusion-group B), with 2516 patients (44.08%) who underwent cAAAs OS without perfusion of the renal arteries and 3192 patients (55.92%) with perfusion. In group B, four types of renal perfusion were reported. Among the 21 studies included, 10 reported on selective renal perfusion in cAAA OS, with several types of fluids described: (1) "enriched" Ringer's solution, (2) "Custodiol" (Istidine-tryptophan-ketoglutarate or Custodiol HTKsolution), (3) other cold (4 °C) solutions (i.e., several combinations of 4 °C isotonic heparinized balanced salt solution containing mannitol, sodium bicarbonate, and methylprednisolone), and (4) warm blood. Thirty-day mortality for patients in group A was 4.25% (107/2516) vs. 4.29% (137/3192) in group B. The reported incidence of AKI and new onset of dialysis was, respectively, 22.14% (557/2516) and 5.45% (137/2516) for group A and 22.49% (718/3192) and 4.32% (138/3192) for group B. A total of 579 patients presented with chronic kidney disease (CKD) at admission across all studies, which included 350 (13.91%) in group A vs. 229 (7.17%) in group B. Acute kidney injury, 30-day mortality, and new-onset dialysis rate were reported in four subgroups: (1) In the "Ringer" group, 30-day mortality was 2.52% (3/113), AKI affected 27.73% (33/119) of patients, and the new-onset dialysis rate was 2.52% (3/113). (2) In the "Custodiol" group, 30-day mortality was 3.70% (3/81), AKI affected 20.17% (24/81) of patients, and the new-onset dialysis rate was 2.46% (2/81). (3) In the "cold solutions" group (i.e., NaCl and mannitol), 30-day mortality was 4.38% (130/2966), AKI affected 21.81% (647/2966) of patients, and the new-onset dialysis rate was 4.48% (133/2966). (4) In the "Warm blood" group, 30-day mortality was 3.85% (1/26), AKI affected 53.84% (14/26) of patients, and the new-onset dialysis rate was 0% (0/26).

CONCLUSIONS

This systematic review highlights the lack of standard definitions for AKI, CKD, and the type of renal perfusion. Despite similar results in terms of AKI and 30-day mortality, renal perfusion seems to be protective of the new-onset hemodialysis rate. Moreover, Custodiol appears to have lower rates of AKI and hemodialysis than the other perfusion types. A prospective randomized controlled trial to perform further subgroup analysis and research the various types of renal perfusion may be necessary to identify possible benefits.

Tabular review of contemporary open surgical repair experiences for treatment of thoracoabdominal aortic aneurysms

Open surgical repair of thoracoabdominal aortic aneurysms (TAAAs) is one of the most challenging operations due to extensive surgical dissection and exposure, risk of complications and need for reconstruction of the aorta and its branches. In the last two decades, endovascular techniques have evolved and now are considered a viable alternative to open surgical repair in patients with suitable anatomy. Regardless of which technique is selected, open or endovascular, reduction of postoperative morbidity and mortality requires large clinical volume, optimal patient selection and a multidisciplinary team that can take care of the surgical, anesthetic, critical care and postoperative issues that occur after these operations. The aim of this article is to summarize the clinical data on open surgical repair of thoracoabdominal aortic aneurysms in a schematic tabular format.

IFABP levels predict visceral malperfusion in the first hours after open thoracoabdominal aortic repair

Introduction

Intestinal ischemia after open thoracoabdominal aortic repairs, is a rare but devastating complication, associated with high mortality. Notoriously challenging to diagnose, visceral malperfusion necessitates immediate surgical attention. Intestinal fatty acid-binding protein (IFABP) has been proposed as a biomarker for the diagnosis of intestinal wall damage. In this prospectively conducted, observational study we evaluated the diagnostic capacity of IFABP levels in patients' serum and their correlation with visceral malperfusion.

Methods

23 patients undergoing open thoracoabdominal aortic repairs were included in this study and 8 of them were diagnosed postoperatively with visceral malperfusion-defined as a partial or complete thrombotic occlusion of the superior mesenteric artery and/or the coeliac trunk. IFABP levels and laboratory parameters often associated with intestinal ischemia (leucocytes, CRP, PCT and lactate) were measured at baseline, directly postoperatively, and at 12, 24 and 48 h after surgery. Postoperative visceral malperfusion-as revealed in CT angiography-was assessed and the predictive ability of IFABP levels to detect visceral malperfusion was evaluated with receiver-operator curve analysis.

Results

Patients with visceral malperfusion had a relevant risk for a fatal outcome (p = .001). IFABP levels were significantly elevated directly postoperatively and at 12 h after surgery in cases of visceral malperfusion. High IFABP concentrations in serum detected visceral malperfusion accurately during the first 12 h after surgery, with the maximum diagnostic ability achieved immediately after surgery (AUC 1, Sensitivity 100%, Specificity 100%, p < .001).

Conclusion

We conclude, that IFABP measurements during the first postoperative hours after open thoracoabdominal aortic surgery can be a valuable tool for reliable and timely detection of visceral malperfusion.

Renal perfusion in complex abdominal aortic aneurysm open repair: a scoping review

INTRODUCTION

To perform a scoping review analyzing the current evidence reporting on acute kidney injury (AKI) after elective open surgery (OS) of complex abdominal aortic aneurysms (c-AAAs) and evaluate the impact of renal perfusion, and the different types of solutions on renal morbidity.

EVIDENCE ACQUISITION

Research questions were defined, and a literature search was performed following the PRISMA guidelines for scoping reviews. Multicenter, single-center observational studies were considered eligible. No abstracts only and unpublished literature were included.

EVIDENCE SYNTHESIS

Two hundred and fifty studies were screened, 20 studies met screening criteria and were included, reporting 1552 patients treated for c-AAAs. The majority did not receive renal perfusion and the others received different types of renal perfusions. Acute kidney injury is a common complication after c-AAAs OS, with an incidence up to 32.5%. Heterogeneity in AKI classifications reduce the ability to compare outcomes after perfusion and nonperfusion strategies. Pre-existing CKD, ischemic injury due to suprarenal aortic clamping are major determinants of AKI after aortic surgery. Most papers reported chronic kidney disease (CKD) at admission. Another debated topic is the indication for renal perfusion during c-AAAs OS. Controversial results for cold renal perfusion have been found.

CONCLUSIONS

In the context of c-AAAs, this review identified the need to standardize the definition of AKI to reduce reporting bias. Besides this, it showed the need to assess the indication for renal perfusion and the type of perfusion solution to be used.

Onset of Adverse Abdominal Events Due to Intestinal Ischemia-Reperfusion Injury after Aortic Cross-Clamping Is Associated with Elevated HSP70 Serum Levels in the Early Postoperative Phase

Tissue injury of the viscera during open thoracoabdominal aortic (TAA) reconstructions has been reported as the aftermath of the ischemia-reperfusion mechanism following supracoeliac aortic cross-clamping. Abdominal complications after open aortic reconstructions, although rare through the intraoperative implementation of selective visceral artery blood perfusion, are associated with high rates of reinterventions and a poor prognosis. Recent animal experiments demonstrated that provoking mesenteric ischemia in rats induces the leukocyte-mediated transcription of heat-shock protein 70 (HSP70), a chaperone belonging to the danger-associated molecular pattern proteins (DAMPs). Translating these findings clinically, we investigated the serum levels of HSP70 in patients undergoing open aortic reconstructions with supracoeliac clamping. We postoperatively observed a relevant induction of HSP70, which remained significantly elevated in cases of postoperative abdominal complications (paralytic ileus, abdominal compartment syndrome, and visceral malperfusion). The receiver-operator curve analysis revealed the reliable prognostic accuracy of HSP70 as a biomarker for these complications as soon as 12 h post-operation (AUC 0.908, sensitivity 88.9%, specificity 83.3%). In conclusion, measuring HSP70 serum levels in the early postoperative phase may serve as a further adjutant in the diagnostic decision making for both the vascular surgeon and intensivist for the timely detection and management of abdominal complications following open TAA surgery.

Capturing the Complexity of Open Abdominal Aortic Surgery in the Endovascular Era

OBJECTIVE

Volume and quality benchmarks for open abdominal aortic surgery and particularly open aortic aneurysm repair (OAR) in the endovascular era are guided by the Society for Vascular Surgery (SVS) guidelines, but the Vascular Quality Initiative (VQI) OAR module fails to capture the full spectrum of complex OAR. We hypothesized that VQI-ineligible complex OAR is the dominant form of open repairs performed at a VQI-participating tertiary center.

METHODS

All OAR cases performed at a single tertiary care center from 2007 to 2020 were reviewed. The VQI OAR criteria were applied with exclusions (non-VQI) defined as concomitant renal bypass, clamping above the superior mesenteric artery (SMA) or celiac artery, repairs performed for trauma, anastomotic aneurysm, isolated iliac aneurysm, or infected aneurysms. Linear regression was used to assess temporal trends.

RESULTS

Among a total of 481 open abdominal aortic operations, 355 (74%) were OAR. The average annual OAR volume remained stable over 14 years (25 ± 6; P = .46). Non-VQI OAR comprised 54% of all cases and persisted over time (R² = .047, P = .46). Supra-celiac clamping (35%) was often necessary. The proportion of endograft explantation cases significantly increased over time from 4% in 2007 to 20% in 2019 (P = .01). Infectious indications represented 20% (n = 70) of cases. Visceral branch grafts were performed in 16% of all cases. OAR for ruptured aneurysm constituted 10% of cases. Thirty-day mortality was significantly higher in non-VQI vs. VQI-eligible OAR cases (10% vs. 4%; P = .04).

CONCLUSIONS

Complex OAR comprises a majority of OAR cases in a contemporary tertiary referral hospital, yet these cases are not accounted for in the VQI. Creation of a "complex OAR" VQI module would capture these cases in a quality-driven national registry and help to better inform benchmarks for volume and outcomes in aortic surgery.