An Examination of Concurrent and Incremental Validity of Four Mindfulness Scales

General consensus among psychologists supports the beneficial effects of mindfulness in the treatment of a wide range of clinical conditions such as personality, mood, and anxiety disorders. Several scales used to assess this psychological construct, mainly rooted in Eastern traditions, are currently available to researchers and clinicians. However, the conceptualization and measurement of mindfulness has been considerably diverse. The present study examines the concurrent and incremental validity of four scales: the Philadelphia Mindfulness Scale (PHLMS), the Toronto Mindfulness Scale (TMS), the Five-Facet Mindfulness Questionnaire (FFMQ), and the Langer Mindfulness Scale (LMS). Two independent samples of 176 adults and 397 students, respectively, were recruited. With few exceptions, results were consistent across the two samples and indicated that measures based on an Eastern conceptualization of mindfulness (TMS, PHLMS, and FFMQ) show a different pattern of association with the chosen outcomes compared to the LMS, which is based on a Western conceptualization. Overall, the PHLMS showed the strongest predictive effects and the LMS the weakest in terms of both number of predicted criteria and average effect size. Implications for research and practice are discussed

Personalized Ventilation to Multiple Patients Using a Single Ventilator : Description and Proof of Concept

Objectives: To design and test a ventilator circuit that can be used for ventilation of two or more patients with a single ventilator, while allowing individualization of tidal volume, fractional concentration of oxygen, and positive end-expiratory pressure to each patient, irrespective of the other patient’s respiratory system mechanics. Design: Description and proof of concept studies. Settings: Respiratory therapy laboratory. Subjects: Ventilation of mechanical test lungs. Interventions: Following a previously advocated design, we used components readily available in our hospital to assemble two “bag-ina- box” breathing circuits. Each patient circuit consisted of a flexible bag in a rigid container connected via one-way valve to a test lung, along with an inline positive end-expiratory pressure valve, connected to the ventilator’s expiratory limb. Compressed gas fills the bags during “patient” exhalation. During inspiration, gas from the ventilator, in pressure control mode, enters the containers and displaces gas from the bags to the test lungs. We varied tidal volume, “respiratory system” compliance, and positive end-expiratory pressure in one lung and observed the effect on the tidal volume of the other. Measurements and Main Results: We were able to obtain different tidal volume, dynamic driving pressure, and positive end-expiratory pressure in the two lungs under widely different compliances in both lungs. Complete obstruction, or disconnection at the circuit connection to one test lung, had minimal effect (< 5% on average) on the ventilation to the co-ventilated lung. Conclusions: A secondary circuit “bag-in-the-box” system enables individualized ventilation of two lungs overcoming many of the concerns of ventilating more than one patient with a single ventilator.Medicine, Faculty ofNon UBCAnesthesiology, Pharmacology and Therapeutics, Department ofReviewedFacultyResearcherPostdoctora

Differences in the control of breathing between Andean highlanders and lowlanders after 10 days acclimatization at 3850 m

We used Duffin's isoxic hyperoxic ( mmHg) and hypoxic ( mmHg) rebreathing tests to compare the control of breathing in eight (7 male) Andean highlanders and six (4 male) acclimatizing Caucasian lowlanders after 10 days at 3850 m. Compared to lowlanders, highlanders had an increased non-chemoreflex drive to breathe, characterized by higher basal ventilation at both hyperoxia (10.5 ± 0.7 vs. 4.9 ± 0.5 l min−1, P= 0.002) and hypoxia (13.8 ± 1.4 vs. 5.7 ± 0.9 l min−1, P < 0.001). Highlanders had a single ventilatory sensitivity to CO2 that was lower than that of the lowlanders (P < 0.001), whose response was characterized by two ventilatory sensitivities (VeS1 and VeS2) separated by a patterning threshold. There was no difference in ventilatory recruitment thresholds (VRTs) between populations (P= 0.209). Hypoxia decreased VRT within both populations (highlanders: 36.4 ± 1.3 to 31.7 ± 0.7 mmHg, P < 0.001; lowlanders: 35.3 ± 1.3 to 28.8 ± 0.9 mmHg, P < 0.001), but it had no effect on basal ventilation (P= 0.12) or on ventilatory sensitivities in either population (P= 0.684). Within lowlanders, VeS2 was substantially greater than VeS1 at both isoxic tensions (hyperoxic: 9.9 ± 1.7 vs. 2.8 ± 0.2, P= 0.005; hypoxic: 13.2 ± 1.9 vs. 2.8 ± 0.5, P < 0.001), although hypoxia had no effect on either of the sensitivities (P= 0.192). We conclude that the control of breathing in Andean highlanders is different from that in acclimatizing lowlanders, although there are some similarities. Specifically, acclimatizing lowlanders have relatively lower non-chemoreflex drives to breathe, increased ventilatory sensitivities to CO2, and an altered pattern of ventilatory response to CO2 with two ventilatory sensitivities separated by a patterning threshold. Similar to highlanders and unlike lowlanders at sea-level, acclimatizing lowlanders respond to hypobaric hypoxia by decreasing their VRT instead of changing their ventilatory sensitivity to CO2