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Aortic valvular stenosis remains the most common debilitating valvular heart lesion. Despite the benefit of aortic valve (AV) replacement, many high-risk patients cannot tolerate surgery. AV implantation treats aortic stenosis without subjecting patients to sternotomy, cardiopulmonary bypass (CPB), and aorta cross-clamping. This transcatheter procedure is performed via puncture of the left ventricular (LV) apex or percutaneously, via the femoral artery or vein. Patients undergo general anesthesia, intense hemodynamic manipulation, and transesophageal echocardiography (TEE). To elucidate the role of the anesthesiologist in the management of transcatheter AV implantation, we review the literature and provide our experience, focusing on anesthetic care, intraoperative events, TEE, and perioperative complications. Two approaches to the aortic annulus are performed today: transfemoral retrograde and transapical antegrade. Iliac artery size and tortuosity, aortic arch atheroma, and pathology in the area of the (LV) apex help determine the preferred approach in each patient. A general anesthetic is tailored to achieve extubation after procedure completion, whereas IV access and pharmacological support allow for emergent sternotomy and initiation of CPB. Rapid ventricular pacing and cessation of mechanical ventilation interrupts cardiac ejection and minimizes heart translocation during valvuloplasty and prosthesis implantation. Although these maneuvers facilitate exact prosthesis positioning within the native annulus, they promote hypotension and arrhythmia. Vasopressor administration before pacing and cardioversion may restore adequate hemodynamics. TEE determines annulus size, aortic pathology, ventricular function, and mitral regurgitation. TEE and fluoroscopy are used for positioning the introducer catheter within the aortic annulus. The prosthesis, crimped on a valvuloplasty balloon catheter, is implanted by inflation. TEE immediately measures aortic regurgitation and assesses for aortic dissection. After repair of femoral vessels or LV apex, patients are allowed to emerge and assessed for extubation. Observed and published complications include aortic regurgitation, prosthesis embolization, mitral valve disruption, hemorrhage, aortic dissection, CPB, stroke, and death. Transcatheter AV implantation relies on intraoperative hemodynamic manipulation for success. Transfemoral and transapical approaches pose unique management challenges, but both require rapid ventricular pacing, the management of hypotension and arrhythmias during beating-heart valve implantation, and TEE. Anesthesiologists will care for debilitated patients with aortic stenosis receiving transcatheter AV implantation.
Small bowel obstruction after intra-abdominal surgery is a common cause of morbidity necessitating reoperation. The aim of this study was to determine the feasibility of and indications for laparoscopic surgery for acute adhesive small bowel obstruction (AASBO). We conducted a retrospective review of all patients with AASBO who underwent laparoscopic adhesiolysis at a major university medical center. Laparoscopic treatment was performed successfully in 16 patients, and conventional treatment was performed in 13 patients. The rate of conversion from laparoscopic to open was 16.7 per cent. In 15 of 16 total patients who underwent laparoscopic surgery, laparoscopic bandlysis was performed and one patient underwent laparoscopic adhesiolysis. Laparoscopic surgery was performed successfully in nine who had a single adhesive band demonstrated on an abdominal CT, and conventional surgery was performed in all 10 patients without a single adhesive band identified radiographically. Abdominal CT scans facilitate the selection of operative approach for AASBO based on preoperative identification of the obstruction site. Laparoscopic adhesiolysis is a safe and effective treatment modality for patients with AASBO with a single band or single transition zone identified by preoperative imaging.
Treatment of primary and secondary hepatic malignancies with transarterial chemoembolization represents an essential component of interventional oncology. This article discusses patient selection, procedure technique, results, and complications associated with transarterial chemoembolization.
BACKGROUND - This study describes a thoracoscopic technique to reliably locate and excise lung nodules that were not thought to be thoracoscopically visible or instrumentally palpable.
METHODS - Initial laboratory studies succeeded in selecting a technetium 99m gamma-emitting solution, technetium 99m macro-aggregated albumin, that remained localized in lung parenchyma after percutaneous placement. Subsequently, 84 patients with solitary small nodules underwent computed tomography (CT)-guided percutaneous placement of this technetium solution in or near the nodule. Thoracoscopic localization with a radioprobe and excisional biopsy followed.
RESULTS - In 3 patients, the previous lesion was not present on the CT scan done on the day of surgery. The 81 remaining patients underwent radiotracer placement and operation. No tracer activity was present in the lung in 4 patients, and open thoracotomy was necessary to locate the lesion. The lesion was successfully localized and excised in 77 patients (95.1%), and 71 underwent thoracoscopic excisional biopsy. Four underwent intentional thoracotomy for deep small nodules in which the tracer was used to guide the open biopsy. Two required conversion from thoracoscopy to thoracotomy because the anatomic location of the lesion prevented a thoracoscopic staple excision. Fifty percent of the lesions were benign, 39% were primary lung cancers, and additional 11% were either solitary metastatic lesions or lymphoma. No patients died, and morbidity rate was 16% (arrhythmias or pneumothoraces).
CONCLUSIONS - Radiotracer-guided thoracoscopic biopsy was 95% reliable for subsequent surgical successful localization and excision of small nodules. This technique can be expanded to localize deep lesions for open thoracotomy and be used to prevent thoracotomy in 50% of patients with benign disease.
The field of interventional oncology includes tumor ablation as well as the use of transcatheter therapies such as embolization, chemoembolization, and radioembolization. Terminology and reporting standards for tumor ablation have been developed. The development of standardization of terminology and reporting criteria for transcatheter therapies should provide a similar framework to facilitate the clearest communication among investigators and provide the greatest flexibility in comparing established and emerging technologies. An appropriate vehicle for reporting the various aspects of catheter directed therapy is outlined, including classification of therapies and procedure terms, appropriate descriptors of imaging guidance, and terminology to define imaging and pathologic findings. Methods for standardizing the reporting of outcomes toxicities, complications, and other important aspects that require attention when reporting clinical results are addressed. It is the intention of the group that adherence to the recommendations will facilitate achievement of the group's main objective: improved precision and communication for reporting the various aspects of transcatheter management of hepatic malignancy that will translate to more accurate comparison of technologies and results and, ultimately, to improved patient outcomes.
OBJECTIVE - A single institution's experience with CT-guided percutaneous radiofrequency ablation of biopsy-proven renal cell carcinomas (RCCs) was studied to determine the disease-free survival and complication rate.
MATERIALS AND METHODS - Data from 125 RCCs in 104 patients treated with curative intent was reviewed. Radiofrequency ablation treatments were performed using conscious sedation and local anesthesia. Patients were followed with contrast-enhanced CT or MRI. Tumor control was defined as the absence of contrast enhancement in the tumor on CT or MRI.
RESULTS - Tumor size ranged from 0.6 to 8.8 cm (mean, 2.7 cm; SD, 1.5 cm). Of the 125 treated tumors, 116 (93%) were completely ablated (109 in a single ablation session, seven after a second ablation session) with a mean follow-up interval of 13.8 months. All 95 RCCs smaller than 3.7 cm were completely ablated, and 21 (70%) of 30 larger tumors were completely ablated, with nine showing evidence of residual viable tumor on follow-up scans. Tumor size smaller than 3.7 cm was significantly associated with achieving complete tumor eradication (p < 0.001). With each 1-cm increase in tumor diameter over 3.6 cm, the likelihood of tumor-free survival decreased by a factor of 2.19 (p < 0.001). There were 8 (8%) complications, none of which resulted in long-term morbidity.
CONCLUSION - CT-guided percutaneous radiofrequency ablation is a safe method to treat small RCCs. This study indicates that radiofrequency ablation can reliably eradicate RCCs smaller than 3.7 cm. Treatment of larger RCCs will result in an increased risk of residual RCC.
Interventional Oncology is an exciting area of Interventional Radiology that represents one of the most rapidly expanding areas in the specialty. These vascular and nonvascular procedures are similar to or identical to other procedures performed by Interventional Radiologists, making practice development feasible in both the academic and private sectors. In this article, practical methods to target and expand individual practices are addressed along with ways to use physician extenders to maximize efficiency in practice.
PURPOSE - The optimal embolic agent for transhepatic arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) has not been identified. This study reports outcomes of TACE for HCC with Gelfoam powder and polyvinyl alcohol (PVA).
MATERIALS AND METHODS - Eighty-one patients underwent 152 TACE sessions with Gelfoam powder (n = 41) or polyvinyl alcohol (PVA) and Ethiodol (n = 40) as the embolic agent. Chemotherapeutic drugs were the same for all patients (50 mg cisplatin, 20 mg doxorubicin, 10 mg mitomycin-c). The groups were compared based on number of TACE sessions, maximum tumor size, bilirubin level, aspartate and alanine aminotransferase levels, Child-Pugh score, Model for End-stage Liver Disease score, and hepatitis B or C virus positivity. The number of cases of each Child class in each group was also evaluated. Survival starting from the first TACE session was calculated according to Kaplan-Meier analysis. Forty-eight patients died during the study period, 19 received transplants, and 14 were alive at the end of the study period.
RESULTS - The groups were statistically similar in all categories regarding liver function, Child-Pugh score, tumor size, hepatitis status, and percentage of patients with Child class A, B, and C disease. The number of TACE sessions was significantly greater for the Gelfoam powder group (mean, 2.2) versus the PVA group (mean, 1.6; P = .01). Overall survival was similar between groups whether patients who received transplants were included in the analysis (mean, 659 days +/- 83 with Gelfoam powder vs 565 days +/- 71 with PVA; P = .42) or were excluded (mean, 519 days +/- 80 with Gelfoam powder vs 511 days +/- 75 with PVA; P = .93).
CONCLUSION - In similar patient groups, survival after treatment of HCC with TACE with Gelfoam powder or PVA and Ethiodol was similar.