Nicotine addiction management following surgery: a quality improvement approach in the post anesthesia care unit.

QUALITY PROBLEM: For smokers, hospital admission is accompanied by forced involuntary nicotine abstinence due to smoke-free site/grounds policies. An audit of patients admitted to our surgical wards revealed that identification of smoking status was inadequate and that nicotine addiction management (NAM) was infrequently offered. The project aimed to enhance both these metrics by initiating NAM in the post anesthesia care unit (PACU). INITIAL ASSESSMENT: Out of 744 patients admitted to our PACU in August 2015, 54% had their smoking status documented. The 200 patients (27%) out of the 744 were smokers and only 50% were offered NAM before discharge. CHOICE OF SOLUTION: PACU unit staff to determine the smoking status of every patient before discharge from the PACU (later changed to OR nursing staff) and, if a patient was identified as a smoker, to offer NRT (patch and mouth spray only) and initiate therapy prior to transfer of the patient to the ward. IMPLEMENTATION: Data about number of patients admitted, presence of documented smoking status, number of identified smokers, and number offered/accepted nicotine replacement therapy (NRT) were collected at baseline and thereafter quarterly. Engaging video education sessions addressed the education gaps highlighted in a needs assessment. Identification of smoking status was made part of preoperative checklist and NRT was made available in post-operative recovery room. RESULTS: These interventions resulted in an increase in screening for tobacco use from 54% at baseline to 95% and the offer of NRT to smokers from 50 to 89%.

Assessing the accuracy of algorithm-derived cardiorespiratory fitness in surgical patients: a prospective cohort study.

PURPOSE: To determine if a non-exercise algorithm-derived assessment of cardiorespiratory fitness (CRFA) accurately predicted estimated values obtained using a six-minute walk test (CRF6MWD) and the Duke Activity Status Index (CRFDASI). METHODS: Following research ethics board approval, an observational cohort study was conducted in selected, consenting patients undergoing elective surgery. Participants completed questionnaires assessing their self-reported exercise capacity. Their height, weight, waist circumference, and vital signs were measured. A six-minute walk test was performed twice with a 45-min rest interval between tests. The correlation between CRFA and both CRF6MWD and CRFDASI was determined. RESULTS: Two hundred forty-two participants were included. Mean age was 62 (range 45-88 yr); 150 (62%) were male, 87 (36%) self-reported walking or jogging > 16 km per week, and 49 (20%) were current smokers. The CRFA and CRF6MWD were highly correlated (Pearson r = 0.878; P < 0.001). CRFA and CRFDASI were less strongly correlated (Pearson r = 0.252; P < 0.001). Among patients capable of walking > 427 m in the six-minute walk test, CRFA, CRF6MWD, and CRFDASI were equivalent. CONCLUSION: A non-exercise algorithm can estimate cardiorespiratory fitness in patients presenting for elective surgery. The variables required to compute CRFA can be obtained in a clinic setting without the need to engage in formal exercise testing. Further evaluation of CRFA as a predictor of long-term outcome in patients is warranted.

Waterpipe (Hookah) Smoking Among Youth and Women in Canada is New, not Traditional.

INTRODUCTION: When asserting the right of individuals to be free to smoke a hookah (waterpipe [WP]) in public places, the "cultural" importance of the practice is often cited. The purpose of this study was to explore the cultural significance of WP smoking. METHODS: Qualitative methods were used to elicit the views of groups of WP smokers from different cultural backgrounds. RESULTS: Sixteen group discussion sessions with a total of 75 WP smokers aged between 18 and 30 were conducted. A few participants saw culture as a factor supporting WP smoking initiation and maintenance. The vast majority indicated that WPs being perceived as "healthier" than cigarettes, and the availability of flavored shisha as important factors in their initiation and ongoing use. Most started smoking before the age of 18 calling it a "high school thing" and admitted that they had easy access to WP cafés. Many indicated that they did not know if they were smoking tobacco or a "herbal" substance. CONCLUSION: Peer influence, availability of flavored products and facile access to WP cafés are major factors in WP initiation. Ethno-cultural traditions play only a minor role. The assertion that cultural traditions and practice are inherent in WP smoking as implied by media and marketing was not supported by our findings. Contemporary use of WP is spreading among new non-traditional users. Lack of knowledge about the harms of WP smoking indicates a need for education and regulation to require packaging and health warning labels and restrictions on access, especially to minors.

Exploring Attitudes of Children 12-17 Years of Age Toward Electronic Cigarettes.

The purpose of this study is to explore electronic cigarettes (EC) use among youth. Focus group sessions with youth (aged 12-17) were held to explore their knowledge and attitudes about EC use. Content analysis techniques were used. There has been an increase in the visibility and accessibility of EC in the past few years among youth. Compared with conventional cigarettes (CC), youth indicated that they would be more willing to use EC under their peer influence. This was motivated by the perception that EC were less harmful. Among youth EC are perceived as less harmful, easier to access and use than CC. Youth do not appear to have received much education about EC. However, they were not convinced that EC were risk free. Clear and unambiguous education about the risk of engaging in any form of smoking/vaping and enforcement of access restrictions appear to be required.

Knowledge About the Waterpipe (Hookah), a Qualitative Assessment Among Community Workers in a Major Urban Center in Canada.

Waterpipe (WP) use has surged in popularity since the introduction of flavoured shisha. It is now an increasingly popular form of smoking among youth in North America. Health professionals/educators knowledge about the WP may well be inadequate. This study, using qualitative methods, sought to explore the knowledge and attitude of leaders in the community toward the WP. Family physicians, pharmacists, tobacco counsellors, social workers and educators were invited to participate in a one-one interview using open-ended questions. A total of 27 interviews were conducted. Individuals from Eastern Mediterranean backgrounds raised doubt about the overemphasised cultural significance of the WP and perceived this as a marketing strategy by industry. Most felt that WP smokers believed the WP to be less harmful than cigarettes and that the use of flavoured tobacco was motivating people to smoke. Participants believed that education should be directed at the general public and healthcare professionals, suggesting school programs and the use of social media to inform young smokers. Most thought that the current practices regarding packaging and second hand smoke exposure are confusing. They identified the lack of knowledge, poor enforcement procedures, "so called cultural aspects" and the economic impact of banning the WP on small businesses as barriers to change. Despite the awareness of an increase in WP use, our participants recognized that little has been done to curb this problem. Our findings emphasize the need for further education and better legislation to regulate WP use and availability.

'Herbal' but potentially hazardous: an analysis of the constituents and smoke emissions of tobacco-free waterpipe products and the air quality in the cafés where they are served.

BACKGROUND: There are limited data on the composition and smoke emissions of 'herbal' shisha products and the air quality of establishments where they are smoked. METHODS: Three studies of 'herbal' shisha were conducted: (1) samples of 'herbal' shisha products were chemically analysed; (2) 'herbal' and tobacco shisha were burned in a waterpipe smoking machine and main and sidestream smoke analysed by standard methods and (3) the air quality of six waterpipe cafés was assessed by measurement of CO, particulate and nicotine vapour content. RESULTS: We found considerable variation in heavy metal content between the three products sampled, one being particularly high in lead, chromium, nickel and arsenic. A similar pattern emerged for polycyclic aromatic hydrocarbons. Smoke emission analyses indicated that toxic byproducts produced by the combustion of 'herbal' shisha were equivalent or greater than those produced by tobacco shisha. The results of our air quality assessment demonstrated that mean PM2.5 levels and CO content were significantly higher in waterpipe establishments compared to a casino where cigarette smoking was permitted. Nicotine vapour was detected in one of the waterpipe cafés. CONCLUSIONS: 'Herbal' shisha products tested contained toxic trace metals and PAHs levels equivalent to, or in excess of, that found in cigarettes. Their mainstream and sidestream smoke emissions contained carcinogens equivalent to, or in excess of, those of tobacco products. The content of the air in the waterpipe cafés tested was potentially hazardous. These data, in aggregate, suggest that smoking 'herbal' shisha may well be dangerous to health.

Smoking status and survival: impact on mortality of continuing to smoke one year after the angiographic diagnosis of coronary artery disease, a prospective cohort study.

BACKGROUND: Smoking is an undertreated risk factor for coronary artery disease (CAD) and is associated with adverse outcomes after myocardial infarction. Aims of our study were to determine if management of CAD by medical therapy (MT) alone or with coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI) influence smoking status at one year following angiography and if a change in smoking status at one year influences long term survival. METHODS: Prospective cohort study using the APPROACH registry. Two cohorts were examined: (1) 11,334 patients who returned a one year follow-up questionnaire; (2) 4,246 patients propensity-matched based on their post-angiography treatment - MT or revascularization (RV). Multivariate modeling and survival analysis were used. RESULTS: In the propensity-matched cohort, quit rates at one year were greater among CABG patients (68%) than PCI (37%) or MT patients (47%). Smokers in the RV group, who self-reported quitting at one year, had a significantly reduced mortality compared to those who continued to smoke. CONCLUSIONS: CABG patients were more likely to quit smoking than those treated with MT alone or PCI. Quitting smoking was associated with improved long-term survival; smoking remains a key risk factor for mortality in patients with CAD. These data underscore the importance of nicotine addiction management in patients with CAD and the need to emphasize cessation particularly in those patients undergoing MT or PCI.

Data-driven lossy tube-load modeling of arterial tree: in-human study.

In this paper, we present and validate a data-driven method to lossy tube-load modeling of arterial tree in humans. In the proposed method, the lossy tube-load model is fitted to central aortic and peripheral blood pressure (BP) waves in the time domain. For this purpose, we employ a time-domain lossy tube-load model in which the wave propagation constant is formulated to two terms: one responsible for the alteration of wave amplitude and the other for the transport delay. Using the experimental BP data collected from 17 cardiac surgery patients, we showed that the time-domain lossy tube-load model is able to accurately represent the relation between central aortic versus upper-limb and lower-limb BP waves. In addition, the comparison of lossy versus lossless tube-load models revealed that (1) the former outperformed the latter in general with the root-mean-squared errors (RMSE) of 3.1 mm Hg versus 3.5 mm Hg, respectively (p-value < 0.05), and (2) the efficacy of the former over the latter was more clearly observed in case the normalized difference in the mean central aortic versus peripheral BP was large; when the difference was >5% of the underlying mean BP, lossy and lossless models showed the RMSE of 2.7 mm Hg and 3.7 mm Hg, respectively (p-value < 0.05).

Doxycycline reduces cardiac matrix metalloproteinase-2 activity but does not ameliorate myocardial dysfunction during reperfusion in coronary artery bypass patients undergoing cardiopulmonary bypass.

OBJECTIVES: Matrix metalloproteinase-2 proteolyzes intracellular proteins in the heart and induces acute myocardial contractile dysfunction in ischemia-reperfusion injury. Doxycycline, a matrix metalloproteinase inhibitor, prevented matrix metalloproteinase-2-induced troponin I cleavage in rat hearts and improved contractile function following ischemia-reperfusion. In patients undergoing coronary artery bypass graft surgery with cardiopulmonary bypass, increased atrial matrix metalloproteinase-2 activity was inversely correlated with cardiac mechanical function at 3 hours reperfusion. We performed a study in patients with coronary artery disease undergoing primary elective coronary artery bypass graft surgery with cardiopulmonary bypass to determine whether doxycycline reduces cardiac mechanical dysfunction, matrix metalloproteinase activity, and troponin I degradation after reperfusion. DESIGN: Randomized, double-blinded, placebo-controlled study. SETTING: University of Alberta Hospital. PATIENTS: Forty-two patients with coronary artery disease undergoing coronary artery bypass graft surgery with cardiopulmonary bypass. INTERVENTIONS: Patients were randomized to receive either oral administration of 20 mg of doxycycline or matching placebo pill twice a day at least 2 days prior to surgery, on the day of surgery, and for the first 3 postoperative days. MEASUREMENTS AND MAIN RESULTS: Left ventricular stroke work index was examined prior to cardiopulmonary bypass and at 24 hours reperfusion. Right atrial biopsies were collected before cardiopulmonary bypass and 10 minutes after aortic cross-clamp release to determine matrix metalloproteinase-2 activity and troponin I level. Blood was collected to determine matrix metalloproteinase activity and interleukin-6, C-reactive protein, and troponin I levels. Cardiac 72-kDa matrix metalloproteinase-2 activity was lower upon reperfusion in biopsies from the doxycycline group (p = 0.01), and the increase of matrix metalloproteinase-2 activity in the placebo group due to reperfusion did not appear in the doxycycline group (p = 0.05). Doxycycline, however, did not ameliorate cardiac mechanical dysfunction following reperfusion or the cardiopulmonary bypass-coronary artery bypass graft-induced increased plasma matrix metalloproteinase-9, interleukin-6, and C-reactive protein levels. Cardiopulmonary bypass-coronary artery bypass graft or doxycycline did not change tissue or plasma troponin I levels at 10 minutes reperfusion. CONCLUSIONS: Although doxycycline did not improve myocardial stunning following coronary artery bypass graft surgery with cardiopulmonary bypass, it reduced cardiac matrix metalloproteinase-2 activity in these patients. A larger trial and/or higher dose of doxycycline may yet be warranted.

Comparative study on tube-load modeling of arterial hemodynamics in humans.

In this paper, we assess the validity of two alternative tube-load models for describing the relationship between central aortic and peripheral arterial blood pressure (BP) waveforms in humans. In particular, a single-tube (1-TL) model and a serially connected two-tube (2-TL) model, both terminated with a Windkessel load, are considered as candidate representations of central aortic-peripheral arterial path. Using the central aortic, radial and femoral BP waveform data collected from eight human subjects undergoing coronary artery bypass graft with cardiopulmonary bypass procedure, the fidelity of the tube-load models was quantified and compared with each other. Both models could fit the central aortic-radial and central aortic-femoral BP waveform pairs effectively. Specifically, the models could estimate pulse travel time (PTT) accurately, and the model-derived frequency response was also close to the empirical transfer function estimate obtained directly from the central aortic and peripheral BP waveform data. However, 2-TL model was consistently superior to 1-TL model with statistical significance as far as the accuracy of the central aortic BP waveform was concerned. Indeed, the average waveform RMSE was 2.52 mmHg versus 3.24 mmHg for 2-TL and 1-TL models, respectively (p < 0.05); the r² value between measured and estimated central aortic BP waveforms was 0.96 and 0.93 for 2-TL and 1-TL models, respectively (p < 0.05). We concluded that the tube-load models considered in this paper are valid representations that can accurately reproduce central aortic-radial/femoral BP waveform relationships in humans, although the 2-TL model is preferred if an accurate central aortic BP waveform is highly desired.

Remote ischemic preconditioning applied during isoflurane inhalation provides no benefit to the myocardium of patients undergoing on-pump coronary artery bypass graft surgery: lack of synergy or evidence of antagonism in cardioprotection?

BACKGROUND: Two preconditioning stimuli should induce a more consistent overall cell protection. We hypothesized that remote ischemic preconditioning (RIPC, second preconditioning stimulus) applied during isoflurane inhalation (first preconditioning stimulus) would provide more protection to the myocardium of patients undergoing on-pump coronary artery bypass grafting. METHODS: In this placebo-controlled randomized controlled study, patients in the RIPC group received four 5-min cycles of 300 mmHg cuff inflation/deflation of the leg before aortic cross-clamping. Anesthesia consisted of opioids and propofol for induction and isoflurane for maintenance. The primary outcome was high-sensitivity cardiac troponin T release. Secondary endpoints were plasma levels of N-terminal pro-brain natriuretic peptide, high-sensitivity C-reactive protein, S100 protein, and short- and long-term clinical outcomes. Gene expression profiles were obtained from atrial tissue using microarrays. RESULTS: RIPC (n = 27) did not reduce high-sensitivity cardiac troponin T release when compared with placebo (n = 28). Likewise, N-terminal pro-brain natriuretic peptide, a marker of myocardial dysfunction; high-sensitivity C-reactive protein, a marker of perioperative inflammatory response; and S100, a marker of cerebral injury, were not different between the groups. The incidence for the perioperative composite endpoint combining new arrhythmias and myocardial infarctions was higher in the RIPC group than the placebo group (14/27 vs. 6/28, P = 0.036). However, there was no difference in the 6-month cardiovascular outcome. N-terminal pro-brain natriuretic peptide release correlated with isoflurane-induced transcriptional changes in fatty-acid metabolism (P = 0.001) and DNA-damage signaling (P < 0.001), but not with RIPC-induced changes in gene expression. CONCLUSIONS: RIPC applied during isoflurane inhalation provides no benefit to the myocardium of patients undergoing on-pump coronary artery bypass grafting.

Smoking cessation interventions in the pre-admission clinic: assessing two approaches.

PURPOSE: Brief intervention (BI) to encourage patients who smoke to quit is effective and should occur at every patient interaction. If smokers receive a motivational interview in addition to BI and are offered pharmacotherapy to treat nicotine withdrawal, cessation rates may be improved. We compared the uptake, implementation, and effectiveness of these two approaches in the delivery of a smoking cessation intervention during assessments in a pre-admission clinic (PAC). METHODS: The study was performed in the PAC at two tertiary care hospitals. At both hospitals, PAC patients were screened for smoking status, and current smokers were offered the opportunity to participate in a cessation program. Those who agreed were asked to consent to participate in an evaluation of program effectiveness that included a telephone interview about smoking status six months after hospital discharge. A cohort design was used to compare cessation outcomes across PACs during a one-year period of patient recruitment. The primary outcome measure was a self-reported continuous quit rate six months following hospitalization. Secondary outcomes included the number of patients willing to participate and the completeness of the delivery of program components. INTERVENTIONS: A BI delivered at one PAC consisted of brief advice and self-help materials, including handing the patient a business card with an available 1-800 Quit line (a telephone smoking cessation help line). The other PAC offered an intensive intervention (II) that included augmenting the BI with an in-hospital and post-discharge motivational interview and access to nicotine replacement therapy (NRT) during admission. RESULTS: At follow-up, we were able to contact 147 of the 288 smokers who agreed to participate in the evaluation of the program, and the self-reported quit rates for the BI and II interventions were 11.4% and 19.5%, respectively. More than 1,200 current smokers were identified and approached at both PACs during the 12-month patient recruitment period, and 60% of those were willing to accept the offered smoking cessation intervention (either BI or II). Implementation of II was uneven, particularly the delivery of the in-hospital motivational interview and prescription of NRT. Uptake of the 1-800 Quit service after discharge was inadequate. CONCLUSION: The PAC is a feasible location to identify smokers and offer a cessation intervention. There are considerable logistical barriers to the development of an II intervention program as described. A program that incorporates elements of BI and II could offer a practical approach to the implementation of a hospital-wide smoking cessation intervention.

Synergy of isoflurane preconditioning and propofol postconditioning reduces myocardial reperfusion injury in patients.

Either isoflurane preconditioning or high-dose propofol treatment has been shown to attenuate myocardial IRI (ischaemia/reperfusion injury) in patients undergoing CABG (coronary artery bypass graft) surgery. It is unknown whether isoflurane and propofol may synergistically attenuate myocardial injury in patients. The present study investigated the efficacy of IsoPC (isoflurane preconditioning), propofol treatment (postconditioning) and their synergy in attenuating postischaemic myocardial injury in patients undergoing CABG surgery using CPB (cardiopulmonary bypass). Patients (n = 120) selected for CABG surgery were randomly assigned to one of four groups (n = 30 each). After induction, anaesthesia was maintained either with fentanyl and midazolam (control; group C); with propofol at 100 µg x kg(-1) of body weight x min(-1) before and during CPB followed by propofol at 60 µg x kg(-1) of body weight x min(-1) for 15 min after aortic declamping (group P); with isoflurane 1-1.5% end tidal throughout the surgery (group I) or with isoflurane 1-1.5% end tidal before CPB and switching to propofol at 100 µg x kg(-1) of body weight x min(-1) during CPB followed by propofol at 60 µg x kg(-1) of body weight x min(-1) for 15 min after aortic declamping (group IP, i.e. IsoPC plus propofol postconditioning). A joint isoflurane and propofol anaesthesia regimen synergistically reduced plasma levels of cTnI (cardiac troponin I) and CK-MB (creatine kinase MB) and f-FABP (heart-type fatty acid-binding protein) (all P < 0.05 compared with control, group P or group I) and facilitated postoperative myocardial functional recovery. During reperfusion, myocardial tissue eNOS (endothelial NO synthase) protein expression in group IP was significantly higher, whereas nitrotyrosine protein expression was lower than those in the control group. In conclusion, a joint isoflurane preconditioning and propofol anaesthesia regimen synergistically attenuated myocardial reperfusion injury in patients.

Matrix metalloproteinase-7 and ADAM-12 (a disintegrin and metalloproteinase-12) define a signaling axis in agonist-induced hypertension and cardiac hypertrophy.

BACKGROUND: Excessive stimulation of Gq protein-coupled receptors by cognate vasoconstrictor agonists induces a variety of cardiovascular processes, including hypertension and hypertrophy. Here, we report that matrix metalloproteinase-7 (MMP-7) and a disintegrin and metalloproteinase-12 (ADAM-12) form a novel signaling axis in these processes. METHODS AND RESULTS: In functional studies, we targeted MMP-7 in rodent models of acute, long-term, and spontaneous hypertension by 3 complementary approaches: (1) Pharmacological inhibition of activity, (2) expression knockdown (by antisense oligodeoxynucleotides and RNA interference), and (3) gene knockout. We observed that induction of acute hypertension by vasoconstrictors (ie, catecholamines, angiotensin II, and the nitric oxide synthase inhibitor N(G)-nitro-l-arginine methyl ester) required the posttranscriptional activation of vascular MMP-7. In spontaneously hypertensive rats, knockdown of MMP-7 (by RNA interference) resulted in attenuation of hypertension and stopped development of cardiac hypertrophy. Quantitative reverse-transcription polymerase chain reaction studies in mouse models of MMP-7 knockdown (by RNA interference) and gene knockout revealed that MMP-7 controlled the transcription of ADAM-12, the major metalloproteinase implicated in cardiac hypertrophy. In mice with angiotensin II-induced hypertension and cardiac hypertrophy, myocardial ADAM-12 and downstream hypertrophy marker genes were overexpressed. Knockdown of MMP-7 attenuated hypertension, inhibited ADAM-12 overexpression, and prevented cardiac hypertrophy. CONCLUSIONS: Agonist signaling of both hypertension and hypertrophy depends on posttranscriptional and transcriptional mechanisms that involve MMP-7, which is transcriptionally connected with ADAM-12. Approaches targeting this novel MMP-7/ADAM-12 signaling axis could have generic therapeutic potential in hypertensive disorders caused by multiple or unknown agonists.

Impact of a standardized referral to a community pharmacist-led smoking cessation program before elective joint replacement surgery.

INTRODUCTION: Smokers undergoing total joint replacement (TJR) are more likely to develop infections and be re-admitted than non-smokers. The primary purpose of this study was to evaluate the effectiveness of standardized preoperative referral to a community-based pharmacist-led smoking cessation program compared to usual care for patients undergoing TJR. Secondarily, we evaluated the use of the smoking cessation program. METHODS: A pre-post quasi-experimental study was conducted at a central intake clinic that prepares approximately 3000 TJR patients annually. Participants were recruited at a mean of 13±11.1 weeks preoperatively and provided informed consent. Participants in the 'pre' observational phase (OP) received usual care for smoking cessation. For 'post' intervention phase (IP) participants, a referral was sent to a community-based pharmacist-led smoking cessation program. Smoking status was validated on study entry using exhaled carbon monoxide. Participants' smoking status was re-assessed using self-reported point prevalence abstinence at 6 months post-recruitment. RESULTS: We enrolled 120/150 (80%) potential OP candidates and 104/286 (36%) potential IP candidates. The groups were similar on study entry; overall, the mean age of participants was 58.7±9.1 years and 103 (47%) were male. They reported medium nicotine dependence with 37±11.6 mean years smoked. At 6 months post-recruitment, 8 (7%) OP participants self-reported 30-day point prevalence abstinence compared to 21 (20%) IP participants (p=0.003). Only 58 (56%) IP participants complied with the pharmacist referral, with 19 (33%) of those seeing the pharmacist reporting point prevalence abstinence at 6 months compared to only 2 (4%) of the 45 participants who did not see the pharmacist (p<0.001). CONCLUSIONS: Referral to a community smoking cessation program as preoperative standard of care is feasible and can enhance long-term quit rates, but voluntary participation led to low recruitment to the program.

The ankle-to-arm blood pressure index predicts risk of cardiac complications after noncardiac surgery.

BACKGROUND: Peripheral arterial disease, as detected by a reduced ankle-to-arm blood pressure index (AAI), has been shown to predict future cardiac events. However, the utility of measuring the AAI to predict postoperative cardiac complications in patients undergoing noncardiac surgery is unknown. METHODS: We prospectively studied 242 consecutive patients aged 50 yr or older presenting to a university hospital preadmission clinic before elective noncardiac surgery. We performed a standardized clinical evaluation that included calculation of the revised cardiac risk index (rCRI) and measurement of the AAI using both palpation and Doppler techniques. Independent observers, blinded to preoperative assessment and AAI results, ascertained cardiac complications in the first 7 days after surgery. We assessed the ability of an abnormal AAI (

Ballistocardiogram: Mechanism and Potential for Unobtrusive Cardiovascular Health Monitoring.

For more than a century, it has been known that the body recoils each time the heart ejects blood into the arteries. These subtle cardiogenic body movements have been measured with increasingly convenient ballistocardiography (BCG) instruments over the years. A typical BCG measurement shows several waves, most notably the "I", "J", and "K" waves. However, the mechanism for the genesis of these waves has remained elusive. We formulated a simple mathematical model of the BCG waveform. We showed that the model could predict the BCG waves as well as physiologic timings and amplitudes of the major waves. The validated model reveals that the principal mechanism for the genesis of the BCG waves is blood pressure gradients in the ascending and descending aorta. This new mechanistic insight may be exploited to allow BCG to realize its potential for unobtrusive monitoring and diagnosis of cardiovascular health and disease.

Expanding the reach of the Quitline by engaging volunteers to market it in hospitals and shopping venues - a pilot study.

BACKGROUND: In Canada, although there are periodic media campaigns to raise awareness of Quitlines, these services are underused. We sought to determine if a dedicated kiosk, similar to that used in the retail industry but staffed by volunteers trained in smoking cessation techniques, would be effective method to enhance Quitline reach. METHODS: We located a kiosk in the foyer of two hospitals and in two shopping malls in Edmonton, Canada between Feb/2012 and July/2014. The cessation intervention was based on the 5 A's approach. Outcome was assessed by number of visits to the kiosk and referral rates to the Quitline. A cross sectional survey among small sample of visitors was used for evaluation. Descriptive statistics were used to summarize visitors' data. RESULTS: Of 1091 kiosk visitors, 53.3 % were current smokers, of whom 93.3 % indicated a willingness to quit. Of these, 32.1 % requested a Quitline referral at the time of the kiosk visit. Referral requests to the Quitline were greater when the kiosk was located in the non-hospital setting 39.1 % compared to 31.1 % in hospitals (P = 0.2). Referrals from the kiosk represented 6 % of total referrals received by the provincial Quitline during the study period. Following referral the Quitline was able to reach 50 % of those referred, of those, 17 % refused to proceed. At seven month follow up 30 day abstinence rate was 3.8 % of smokers who wished quit. Visitors agreed that the kiosk design was interesting (89.3 %) and increased their knowledge about tobacco and cessation options (88.8 %) and encouraged them to take action to quit (85.7 %). CONCLUSIONS: A "volunteer manned kiosk" can increase awareness of smoking cessation resources in the community and increase referral rates to Quitline services.

Quantification of wave reflection using peripheral blood pressure waveforms.

This paper presents a novel minimally invasive method for quantifying blood pressure (BP) wave reflection in the arterial tree. In this method, two peripheral BP waveforms are analyzed to obtain an estimate of central aortic BP waveform, which is used together with a peripheral BP waveform to compute forward and backward pressure waves. These forward and backward waves are then used to quantify the strength of wave reflection in the arterial tree. Two unique strengths of the proposed method are that 1) it replaces highly invasive central aortic BP and flow waveforms required in many existing methods by less invasive peripheral BP waveforms, and 2) it does not require estimation of characteristic impedance. The feasibility of the proposed method was examined in an experimental swine subject under a wide range of physiologic states and in 13 cardiac surgery patients. In the swine subject, the method was comparable to the reference method based on central aortic BP and flow. In cardiac surgery patients, the method was able to estimate forward and backward pressure waves in the absence of any central aortic waveforms: on the average, the root-mean-squared error between actual versus computed forward and backward pressure waves was less than 5 mmHg, and the error between actual versus computed reflection index was less than 0.03.

Effects of inhibition of myocardial extracellular-responsive kinase and P38 mitogen-activated protein kinase on mechanical function of rat hearts after prolonged hypothermic ischemia.

BACKGROUND: Mitogen-activated protein kinases (MAPKs), including extracellular-responsive kinase (ERK) and p38 MAPK, are activated by stresses associated with hypothermia-rewarming and ischemia-reperfusion. Their activation in heart is associated with beneficial (preconditioning) and adverse effects (apoptosis and impaired contractility). This study determined whether ERK and p38 MAPK activities are altered by hypothermic ischemia and normothermic reperfusion and the consequences of their inhibition on recovery of myocardial function. METHODS: Left ventricular work (L x min(-1) x mm Hg) was assessed during normothermic perfusion (30 min) of isolated rat hearts that were either freshly excised or previously subjected to hypothermic storage (8 hr, 3 degrees C) and rewarming (10 min, 37 degrees C) before normothermic reperfusion (30 min). Phospho-specific immunoblot analysis of p38 MAPK was performed in hearts and various cultured cells. RESULTS: Compared with fresh hearts, hearts subjected to hypothermia and rewarming demonstrated impaired left ventricular work (1.96+/-0.53, n=12 vs. 8.37+/-0.46, n=4, <0.05) during reperfusion. The ERK inhibitor, PD98059 (20 microM), present during storage and rewarming, caused modest improvement (3.66+/-0.75, n=9, <0.05). The p38 MAPK inhibitor, SB202190 (10 microM), when present during reperfusion, improved recovery (to 6.12+/-0.75, n=6, <0.05); it was ineffective if present only during rewarming (1.52+/-0.88, n=4). In rat2 fibroblasts, hypothermia and rewarming activated p38 MAPK and its downstream kinase MAPK-activated protein kinase 2, but not c-Jun N-terminal kinase/stress-activated protein kinase. CONCLUSIONS: Myocardial p38 MAPK and MAPK-activated protein kinase 2 are stimulated by hypothermia, ischemia, and rewarming and are detrimental to recovery of mechanical function of hearts subjected to prolonged hypothermic storage. Inhibition of p38 MAPK may be useful in protocols to improve the recovery of mechanical function of cold-stored hearts.