Factors Influencing Outcome after Open Surgical Repair of Juxtarenal Abdominal Aortic Aneurysms

Francesco Speziale; Massimo Ruggiero; Enrico Sbarigia; Mario Marino; Danilo Menna

Disclosures

Vascular. 2010;18(3):141-146. 

In This Article

Methods

From June 2000 to May 2009, at our academic referral center for vascular surgery, 733 consecutive patients underwent elective repair of an AAA: of these, 192 patients (26.2%) underwent EVAR and 541 underwent open repair (73.8%), 92 (12.5%) who had JR-AAAs had conventional open repair. Patients were excluded if they had suprarenal AAAs, ruptured JR-AAAs treated in emergency, anastomotic pseudoaneurysms, or type IV thoracoabdominal aortic aneurysms (TA-AAs). Patients' clinical and surgical records were retrieved from an electronic database and reviewed. JR-AAAs were diagnosed from preoperative imaging, including color Doppler ultrasonography, computed tomographic (CT) angiography, or magnetic resonance angiography (MRA), and confirmed intraoperatively.

Preoperative Variables

Among the risk factors and morbidity, we defined ischemic cardiopathy as signs of myocardial ischemia on the electrocardiographic (ECG) tracing or echocardiographic evidence of altered myocardial kinesis in patients with or without a history of previous myocardial revascularization procedures. Chronic respiratory insufficiency was defined as a reduction of > 30% in the predicted forced expiratory volume in 1 second (FEV1), associated with an obstructive or restrictive deficit or both in gas exchange. Renal insufficiency was defined as reduced glomerular filtration with a serum creatinine clearance value of < 40 mL/min.

Operative Techniques

With the patient under general anesthesia, in most cases, after a standard xiphoid-to-pubis midline abdominal laparotomy, the aorta was exposed through a transperitoneal approach. In grossly obese patients or those with severe respiratory insufficiency, surgery consisted of a bilateral subcostal laparotomy and a transperitoneal approach to the aorta. In patients with a hostile abdomen owing to multiple previous abdominal laparotomies or patients with CT angiography or MRA findings suggesting inflammatory aneurysms, we used a left lumbotomy with a retroperitoneal approach to the aortic vessels through the left anterior renal fascia. Immediately before clamping, to protect the renal parenchyma, fenoldopam (0.006 γ/kg/min)was infused intravenously and the infusion was continued for 12 hours after surgery. After intravenous infusion of heparin sodium (5,000 IU), the aorta was clamped above one or both renal arteries. The proximal aortic aneurysm neck was exposed by mobilizing the left renal veins and then dissecting the ipsilateral gonadal and subrenal veins. As a routine procedure to make proximal clamping easier to handle, we dissected some of the tendon fibers in the diaphragmatic pillars. After clamping, the renal arteries were perfused with an initial bolus of cold crystalloid solution (lactated Ringer solution) at 4°C, containing methylprednisolone (125 mg/L) and 18% mannitol (12.5 g/L), followed by continuous intrarenal infusion of 20 mL/min of the same solution through selective renal artery cannulation with Fogarty irrigation catheters numbers 6 and 7 (Edwards Lifesciences, Nyon, Switzerland).

Operative Morbidity and Mortality

Postoperative ischemic cardiopathy was defined as signs of ischemia on the postoperative ECG tracing accompanied by increased titers for myocardial necrosis enzyme (troponin ≥ 0.05 ng/mL). We defined postoperative respiratory insufficiency as abnormal lung function tests and blood-gas exchange analyses necessitating prolonged intubation, reintubation, or minimally invasive assisted ventilation, or all three procedures during the immediate postoperative course. Postoperative renal insufficiency was defined as a glomerular filtration rate of < 40 mL/min. Operative mortality was defined as any death, regardless of cause, occurring within 30 days after surgery in or out of the hospital.

Statistical Analysis

All data are expressed as mean ± SD. The possible effects of the major single independent predictive variables on the dependent outcomes cardiac, respiratory, and renal insufficiency in the postoperative period were tested in a univariate analysis and their significance was evaluated with the chi-square test; p values ≥ .05 were considered statistically significant. The probability of overall survival at 1, 3, and 5 years was estimated with the Kaplan-Meier method.

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