Coronary–aortic interaction during ventricular isovolumic contraction

In earlier work, we suggested that the start of the isovolumic contraction period could be detected in arterial pressure waveforms as the start of a temporary pre-systolic pressure perturbation (AICstart, start of the Arterially detected Isovolumic Contraction), and proposed the retrograde coronary blood volume flow in combination with a backwards traveling pressure wave as its most likely origin. In this study, we tested this hypothesis by means of a coronary artery occlusion protocol. In six Yorkshire × Landrace swine, we simultaneously occluded the left anterior descending (LAD) and left circumflex (LCx) artery for 5 s followed by a 20-s reperfusion period and repeated this sequence at least two more times. A similar procedure was used to occlude only the right coronary artery (RCA) and finally all three main coronary arteries simultaneously. None of the occlusion protocols caused a decrease in the arterial pressure perturbation in the aorta during occlusion (P > 0.20) nor an increase during reactive hyperemia (P > 0.22), despite a higher deceleration of coronary blood volume flow (P = 0.03) or increased coronary conductance (P = 0.04) during hyperemia. These results show that the pre-systolic aortic pressure perturbation does not originate from the coronary arteries

Laser spectroscopy for breath analysis : towards clinical implementation

Detection and analysis of volatile compounds in exhaled breath represents an attractive tool for monitoring the metabolic status of a patient and disease diagnosis, since it is non-invasive and fast. Numerous studies have already demonstrated the benefit of breath analysis in clinical settings/applications and encouraged multidisciplinary research to reveal new insights regarding the origins, pathways, and pathophysiological roles of breath components. Many breath analysis methods are currently available to help explore these directions, ranging from mass spectrometry to laser-based spectroscopy and sensor arrays. This review presents an update of the current status of optical methods, using near and mid-infrared sources, for clinical breath gas analysis over the last decade and describes recent technological developments and their applications. The review includes: tunable diode laser absorption spectroscopy, cavity ring-down spectroscopy, integrated cavity output spectroscopy, cavity-enhanced absorption spectroscopy, photoacoustic spectroscopy, quartz-enhanced photoacoustic spectroscopy, and optical frequency comb spectroscopy. A SWOT analysis (strengths, weaknesses, opportunities, and threats) is presented that describes the laser-based techniques within the clinical framework of breath research and their appealing features for clinical use.Peer reviewe

Physician Burnout and Patient Satisfaction with Consultation in Primary Health Care Settings: Evidence of Relationships from a one-with-many Design

Physician burnout, as a prolonged response to chronic emotional and interpersonal stressors on the job, has been associated with suboptimal patient care and deterioration in the patient-provider relationship. Although prior studies have identified a range of factors associated with decreased patient satisfaction, most have been conducted in tertiary care settings, while staff burnout has been examined at the hospital unit-level. To examine the impact of physician burnout on patient satisfaction from consultation in the primary care setting, a cross-sectional survey was conducted in Western Greece. Using a one-with-many design, 30 physicians and 300 of their patients, randomly selected, responded to the survey. Results showed that patient satisfaction correlated significantly with physician emotional exhaustion (r = -.636, p<.01) and physician depersonalization (r = -.541, p<.01). Mixed-effects multi-level models indicated that 34.4% of total variation in patients' satisfaction occurred at the physician level, after adjustment for patients' characteristics. Moreover, physician emotional exhaustion and depersonalisation remained significant factors associated with patient satisfaction with consultation, after controlling for patient and physician characteristics. Patients of physicians with high-exhaustion and high depersonalisation had significantly lower satisfaction scores, compared with patients of physicians with low-exhaustion and low depersonalisation, respectively. Future studies need to explore the mechanisms by which physician burnout affects patient satisfaction