Pre-operative stress testing in the evaluation of patients undergoing non-cardiac surgery: A systematic review and meta-analysis.

BACKGROUND: Pre-operative stress testing is widely used to evaluate patients for non-cardiac surgeries. However, its value in predicting peri-operative mortality is uncertain. The objective of this study is to assess the type and quality of available evidence in a comprehensive and statistically rigorous evaluation regarding the effectiveness of pre-operative stress testing in reducing 30-day post -operative mortality following non -cardiac surgery. METHODS: The databases of MEDLINE, EMBASE, and CENTRAL databases (from inception to January 27, 2016) were searched for all studies in English. We included studies with pre-operative stress testing prior to 10 different non-cardiac surgery among adults and excluded studies with sample size<15. The data on study characteristics, methodology and outcomes were extracted independently by two observers and checked by two other observers. The primary outcome was 30-day mortality. We performed random effects meta-analysis to estimate relative risk (RR) and 95% confidence intervals (95% CI) in two-group comparison and pooled the rates for stress test alone. Heterogeneity was assessed using I2 and methodological quality of studies using Newcastle-Ottawa Quality Assessment Scale. The predefined protocol was registered in PROSPERO #CRD42016049212. RESULTS: From 1807 abstracts, 79 studies were eligible (297,534 patients): 40 had information on 30-day mortality, of which 6 studies compared stress test versus no stress test. The risk of 30-day mortality was not significant in the comparison of stress testing versus none (RR: 0.79, 95% CI = 0.35-1.80) along with weak evidence for heterogeneity. For the studies that evaluated stress testing without a comparison group, the pooled rates are 1.98% (95% CI = 1.25-2.85) with a high heterogeneity. There was evidence of potential publication bias and small study effects. CONCLUSIONS: Despite substantial interest and research over the past 40 years to predict 30-day mortality risk among patients undergoing non-cardiac surgery, the current body of evidence is insufficient to derive a definitive conclusion as to whether stress testing leads to reduced peri-operative mortality.

Addressing statin adverse effects in the clinic: the 5 Ms.

With the release of the 2013 American College of Cardiology/American Heart Association (ACC/AHA) Guideline on the Treatment of Blood Cholesterol to Reduce Atherosclerotic Cardiovascular Risk in Adults, emphasis has been placed on using evidence-based intensity of therapy to reduce atherosclerotic cardiovascular disease (ASCVD) risk, rather than focusing on goal cholesterol levels. Before initiating therapy, however, it is critical that physicians and patients discuss 4 key topics: (1) the benefit of ASCVD risk reduction, (2) medication adverse effects, (3) drug-drug interactions, and (4) patient preferences. To facilitate discussion of statin adverse effects, we present here an evidence-based review of the 5 Ms of statin adverse effects: metabolism, muscle, medication interactions, major organ effects, and memory. "Metabolism" represents the small risk of new-onset diabetes that comes with statins, which is highest in those with diabetes risk factors. "Muscle" requires discussion of the wide range of muscle symptoms that occur with statins but emphasizes that these have been no more prevalent than those experienced with placebo in randomized controlled trials (RCTs). "Medication interactions" emphasize that statins interact with numerous medications. Interaction profiles vary widely between statins, and patients should be made aware of the most common interactions with their prescription. "Major organ effects" prompt the physician to review the possibility of a transient transaminitis as well as the recent observation of rare acute kidney injury with statin use. Both are rare and do not require routine monitoring. Finally, "memory" references the recent observational data suggesting statins may contribute to memory loss and confusion, both of which have not been observed in RCTs and resolve with drug cessation. Reviewing these common effects has the possibility to strengthen the doctor-patient relationship and boost both medication adherence and patient satisfaction.

Broadband reflectance spectroscopy for establishing a quantitative metric of vascular leak using the Miles assay.

Monitoring the physiological effects of biological mediators on vascular permeability is important for identifying potential targets for antivascular leak therapy. This therapy is relevant to treatments for pulmonary edema and other disorders. Current methods of quantifying vascular leak are in vitro and do not allow repeated measurement of the same animal. Using an in vivo diffuse reflectance optical method allows pharmacokinetic analysis of candidate antileak molecules. Here, vascular leak is assessed in mice and rats by using the Miles assay and introducing irritation both topically using mustard oil and intradermally using vascular endothelial growth factor (VEGF). The severity of the leak is assessed using broadband diffuse reflectance spectroscopy with a fiber reflectance probe. Postprocessing techniques are applied to extract an artificial quantitative metric of leak from reflectance spectra at vascular leak sites on the skin of the animal. This leak metric is calculated with respect to elapsed time from irritation in both mustard oil and VEGF treatments on mice and VEGF treatments on rats, showing a repeatable increase in leak metric with leak severity. Furthermore, effects of pressure on the leak metric are observed to have minimal effect on the reflectance spectra, while spatial positioning showed spatially nonuniform leak sites.