Surgical aspects and biological considerations of arteriovenous fistula placement.

Since the Fistula First Initiative was formulated in 2003, providers and payers have increasingly emphasized the need to create more arteriovenous fistulae. To maximize the chances of successful fistula maturation, a thorough understanding of the biology and surgical aspects of fistula placement are essential. A functional endothelium in the target vessels is the prerequisite for the adaptive remodeling of the vessel wall, which has to take place after fistula formation. Mechanoreceptors of the endothelium sense the increase in shear stress and, through a variety of activated signaling cascades, induce the necessary changes and vasodilation of the respective vessels. The successful fistula placement starts with a thorough preoperative evaluation, which focuses on protecting the target vessels and avoiding intravenous catheters and devices. Intraoperatively, the risk of endothelial dysfunction and hyperplasia is further minimized through an atraumatic dissection with minimal manipulation of the vein and artery. The surgical technique should also focus on decreasing the vessel compliance mismatch and avoiding an inflammatory response secondary to hematoma formation. Postoperatively, the fistula must be diligently monitored for the complications of thrombosis, postoperative steal syndrome, neuropathy, aneurysm formation, infection, and high-output cardiac failure. Early recognition of a problem is the key to saving an otherwise doomed fistula. An armamentarium of percutaneous techniques is available to the access surgeon to treat the most common causes of failed access formation. However, in some cases a surgical revision of the access site through patch angioplasty, a jump graft, and graft interposition is necessary to create a fistula which can be successfully used for hemodialysis.

Laser-Assisted Indocyanine Green Dye Angiography for Postoperative Fistulas After Salvage Laryngectomy.

Importance: Pharyngocutaneous fistula formation is an unfortunate complication after salvage laryngectomy for head and neck cancer that is difficult to anticipate and related to a variety of factors, including the viability of native pharyngeal mucosa. Objective: To examine whether noninvasive angiography with indocyanine green (ICG) dye can be used to evaluate native pharyngeal vascularity to anticipate pharyngocutaneous fistula development. Design, Setting, and Participants: This cohort study included 37 patients enrolled from June 1, 2013, to June 1, 2016, and follow-up was for at least 1 month postoperatively. The study was performed at the University of Alabama at Birmingham, a tertiary care center. Included patients were those undergoing salvage total laryngectomy who were previously treated with chemoradiotherapy or radiotherapy alone. Exposures: The ICG dye was injected intraoperatively, and laser-assisted vascular imaging was used to evaluate the native pharyngeal mucosa after the ablative procedure. The center of the native pharyngeal mucosa was used as the reference to compare with the peripheral mucosa, and the lowest mean ICG dye percentage of mucosal perfusion was recorded for each patient. Main Outcomes and Measures: The primary outcome was the formation of a postoperative fistula, which was assessed by clinical and radiographic assessment to test the hypothesis formulated before data collection. Results: A total of 37 patients were included (mean [SD] age, 62.3 [8.5] years; 32 [87%] male and 5 [14%] female); 20 had a history of chemoradiotherapy, and 17 had history of radiotherapy alone. Thirty-four patients (92%) had free flap reconstruction, and 3 had primary closure (8%). Ten patients (27%) developed a postoperative fistula. No significant difference was found in fistula rate between patients who underwent neck dissection and those who did not and patients previously treated with chemoradiotherapy and those treated with radiotherapy alone. A receiver operator characteristic curve was generated to determine the diagnostic performance of the lowest mean ICG dye percentage of mucosal perfusion determined by fluorescence imaging, which was found to be a threshold value of 26%. The area under the curve was 0.85 (95% CI, 0.73-0.97), which was significantly greater than the chance diagonal. The overall mean lowest ICG dye percentage of mucosal perfusion was 31.3%. The mean lowest ICG dye percentage of mucosal perfusion was 22.0% in the fistula group vs 34.9% in the nonfistula group (absolute difference, 12.9%; 95% CI, 5.1%-21.7%). Conclusions and Relevance: Patients who developed postoperative fistulas had lower mucosal perfusion as detected by ICG dye angiography when compared with patients who did not develop fistulas.

Smoking Cessation and Electronic Cigarette Use among Head and Neck Cancer Patients.

OBJECTIVES: (1) Investigate electronic cigarette (e-cig) use among head and neck (HN) cancer patients; (2) define quit methods, success, motivations, and barriers to smoking cessation; and (3) determine the impact of e-cig use in smoking cessation. STUDY DESIGN: Cross-sectional study. SETTING: Tertiary care center. METHODS: An in-office survey was administered to HN cancer patients ≥ 19 years of age with past/present tobacco use. Patient demographics were collected. Quit methods, success, and motivations/barriers were surveyed. The Alcohol Use Disorders Identification Test was used to correlate alcohol use and cessation. Independent variables associated with cessation were studied with Fisher's exact test and Student's t test. Subgroup analysis was performed for e-cig users. RESULTS: Of 110 eligible patients, 106 (96%) enrolled (83% male, 82% Caucasian), of whom 69 (65%) successfully quit. Age of first tobacco use did not differ between the smoking and cessation groups (P = .14), nor did hazardous drinking (30% smoking vs 14% cessation; P = .072). "Cold turkey" (ie, stopping abruptly without smoking cessation aids) was the most common method attempted (n = 88, 83%) and most successful (n = 65, 94%). There was no statistical difference in age, sex, race, drinking, or socioeconomic status between e-cig users and nonusers. Nonusers achieved higher quit rates as compared with e-cig users (72% vs 39%; P = .0057). E-cig use did not decrease the number of cigarettes smoked (463 cigarettes/month) versus that of nonusers (341 cigarettes/month; P = .2). Seventy percent of e-cig users wore a nicotine patch. CONCLUSIONS: HN cancer patients desire smoking cessation. E-cig did not decrease tobacco use, and patients who utilize e-cigs are less likely to achieve smoking cessation.

Optimal Management of Proliferative Verrucous Leukoplakia: A Systematic Review of the Literature.

OBJECTIVE: Proliferative verrucous leukoplakia (PVL) is a rare and recalcitrant form of leukoplakia. The purpose of this review is to further characterize the risk factors, clinical course, and optimal treatment for this highly aggressive, premalignant lesion. DATA SOURCES: Twenty-six articles on PVL with a total of 329 PVL cases. REVIEW METHODS: A systematic review of the literature using Ovid, PubMed, Cochrane Database, and gray literature was conducted of all PVL cases reported between 1985 and 2014. Inclusion criteria required reporting of patient follow-up and recurrence rates. Data were analyzed using descriptive statistics. Student t test and Fisher exact test were used to identify factors associated with malignant transformation. RESULTS: The mean patient age was 63.9 years. Most patients were female (66.9%) and nontobacco users (65.22%). Mean follow-up was 7.4 years, with an average of 9.0 biopsies per patient during this period. Proliferative verrucous leukoplakia exhibited histopathologic features along a progressive spectrum, evolving from leukoplakia to verrucous hyperplasia and ultimately invasive carcinoma. Surgery was the most common treatment implemented, but recurrence rates among 222 patients reached 71.2%. Subgroup analysis of 277 patients identified a 63.9% malignant transformation rate, and 39.6% of patients died of their disease. Age, sex, and tobacco use were not identified as risk factors associated with progression to cancer. CONCLUSIONS: Proliferative verrucous leukoplakia is a rare form of leukoplakia with a high rate of malignant transformation. It necessitates high clinical suspicion, to include a lifetime of close follow-up and repeat biopsies by a health care provider well versed in oral carcinoma.