Knowledge and perceptions about perioperative stroke: a cross-sectional survey of patients scheduled for non-neurologic and non-cardiac surgery.

PURPOSE: Perioperative stroke is associated with significant morbidity and mortality yet patients may not be aware of their risk or receive appropriate counselling. Our objectives were to 1) compare patient's perceived vs calculated risk of stroke; 2) determine level of worry; and 3) assess prior discussion about perioperative stroke risk amongst elective patients undergoing non-cardiac, non-neurologic surgery. METHODS: Over a consecutive four-week period, surveys were distributed at two pre-anesthetic clinics to adult patients scheduled for non-cardiac, non-neurologic surgery. The survey included questions about demographics, perioperative stroke risk factors, patient perception of their quantitative and qualitative stroke risk, level of worry about stroke, and risk discussions. We identified independent predictors of risk underestimation amongst medium- and high-risk patients. RESULTS: Six hundred patients completed the survey (response rate 78%). Of these, 479, 104, and 15 patients were classified as low-, medium-, and high-risk, respectively (with two patients missing this data point). Most medium- (86%) and high-risk (80%) patients did not identify their elevated risk. Amongst medium- and high-risk patients, independent predictors of risk underestimation were lower education and absence of kidney disease. Medium- and high-risk patients were more worried than low-risk patients about perioperative stroke (median [interquartile range] visual analogue scale score 2 [0.5-4] vs 1 [0-2], P = 0.001). Fewer than half of patients had discussed perioperative stroke previously (40%, 23%, and 12% of high-, medium-, and low-risk patients, respectively). CONCLUSIONS: Patients at higher risk of stroke frequently underestimate their risk of perioperative stroke. The majority of patients had not discussed perioperative stroke prior to anesthetic consultation.

Frailty and sarcopenia do not predict adverse events in an elderly population undergoing non-complex primary elective surgery for degenerative conditions of the lumbar spine.

BACKGROUND CONTEXT: Sarcopenia measured by normalized total psoas area (NTPA) has been shown to predict mortality and adverse events (AEs) in numerous surgical populations. The relationship between sarcopenia and postoperative outcomes after surgery for degenerative spine disease (DSD) has not been investigated. PURPOSE: This study aimed to determine the relationships between sarcopenia, frailty, and postoperative AEs in the elderly DSD population. Secondary objectives were to describe the distribution and predictors of NTPA and to determine the relationship between sarcopenia, frailty, and length of stay, discharge to a facility, and in-hospital mortality. STUDY DESIGN: This is an ambispective study from a quaternary care academic center. PATIENT SAMPLE: A total of 102 patients over 65 years old who underwent elective thoracolumbar surgery for DSD between 2009 and 2013 were included in this study. OUTCOME MEASURES: The primary outcome was a composite of perioperative AEs; the secondary outcomes were length of stay, discharge disposition, and in-hospital mortality. METHODS: Total psoas area (TPA) at mid-L3 level on preoperative computed tomography scan adjusted for height (NTPA) defined sarcopenia. The modified frailty index (mFI) of 11 clinical variables defined frailty. The distribution and predictors of sarcopenia (NTPA) were determined. The association of NTPA with AEs, length of stay, discharge disposition to care facility, and mortality was analyzed, including adjusting for known and suspected confounders using multivariate regression. RESULTS: Median Spine Surgical Invasiveness Index was 8 (interquartile range 2-10), and mean NTPA was 674 mm2/m2 (293.21-1636.25). Using the mFI, 20.6% were pre-frail and 19.6% were frail. Inter- and intraobserver reliability for determining NTPA were near perfect with kappa 0.95-0.97 and 0.94-1.00, respectively. The NTPA was independently associated with patient gender and body mass index (BMI) but not frailty (mFI). Age, BMI, mFI, and American Anesthesiologists' Society score were not associated with incidence of postoperative AEs. The NTPA did not predict the occurrence of AE (odds ratio [OR] 1.06 per 100 mm2/m2, 95% confidence interval [CI] 0.91-1.23, p=.45). Similarly, NTPA was not predictive of length of stay (rho=-0.04, p=.67), discharge home (OR 0.95 (95% CI 0.76-1.20) per 100 mm2/m2, p=.70), or death (OR 1.12 (95% CI 0.83-1.53) per 100 mm2/m2, p=.47). In contrast, increasing mFI was associated with increased risk of mortality (OR 3.12 (95% CI 1.21-8.03) per 0.1 increase in frailty score, p=.006). CONCLUSIONS: In contrast to other surgical groups, sarcopenia (NTPA) or frailty (mFI) did not predict acute care complications in a selected population of elderly patients undergoing simple lumbar spine surgery for DSD. Although NTPA can be reliably measured in this population, it may be an inappropriate surrogate for sarcopenia given its anatomical relationship to spinal function.

Internet-Based Resources Frequently Provide Inaccurate and Out-of-Date Recommendations on Preoperative Fasting: A Systematic Review.

Preoperative fasting is important to avoid morbidity and surgery delays, yet recommendations available on the Internet may be inaccurate. Our objectives were to describe the characteristics and recommendations of Internet resources on preoperative fasting and assess the quality and readability of these websites. We searched the Internet for common search terms on preoperative fasting using Google® search engines from 4 English-speaking countries (Canada, the United States, Australia, and the United Kingdom). We screened the first 30 websites from each search and extracted data from unique websites that provided recommendations on preoperative fasting. Website quality was assessed using validated tools (JAMA Benchmark criteria, DISCERN score, and Health on the Net Foundation code [HONcode] certification). Readability was scored using the Flesch Reading Ease score and Flesch-Kincaid Grade Level. A total of 87 websites were included in the analysis. A total of 48 websites (55%) provided at least 1 recommendation that contradicted established guidelines. Websites from health care institutions were most likely to make inaccurate recommendations (61%). Only 17% of websites encouraged preoperative hydration. Quality and readability were poor, with a median JAMA Benchmark score of 1 (interquartile range 0-3), mean DISCERN score 39.8 (SD 12.5), mean reading ease score 49 (SD 15), and mean grade level of 10.6 (SD 2.7). HONcode certification was infrequent (10%). Anesthesia society websites and scientific articles had higher DISCERN scores but worse readability compared with websites from health care institutions. Online fasting recommendations are frequently inconsistent with current guidelines, particularly among health care institution websites. The poor quality and readability of Internet resources on preoperative fasting may confuse patients.

The tumor suppressor folliculin regulates AMPK-dependent metabolic transformation.

The Warburg effect is a tumorigenic metabolic adaptation process characterized by augmented aerobic glycolysis, which enhances cellular bioenergetics. In normal cells, energy homeostasis is controlled by AMPK; however, its role in cancer is not understood, as both AMPK-dependent tumor-promoting and -inhibiting functions were reported. Upon stress, energy levels are maintained by increased mitochondrial biogenesis and glycolysis, controlled by transcriptional coactivator PGC-1α and HIF, respectively. In normoxia, AMPK induces PGC-1α, but how HIF is activated is unclear. Germline mutations in the gene encoding the tumor suppressor folliculin (FLCN) lead to Birt-Hogg-Dubé (BHD) syndrome, which is associated with an increased cancer risk. FLCN was identified as an AMPK binding partner, and we evaluated its role with respect to AMPK-dependent energy functions. We revealed that loss of FLCN constitutively activates AMPK, resulting in PGC-1α-mediated mitochondrial biogenesis and increased ROS production. ROS induced HIF transcriptional activity and drove Warburg metabolic reprogramming, coupling AMPK-dependent mitochondrial biogenesis to HIF-dependent metabolic changes. This reprogramming stimulated cellular bioenergetics and conferred a HIF-dependent tumorigenic advantage in FLCN-negative cancer cells. Moreover, this pathway is conserved in a BHD-derived tumor. These results indicate that FLCN inhibits tumorigenesis by preventing AMPK-dependent HIF activation and the subsequent Warburg metabolic transformation.