Comparison of ventilation during exercise in horses wearing half- and full-face masks

2006 ◽  
Vol 3 (3) ◽  
pp. 131-136 ◽  
Author(s):  
D.J. Marlin ◽  
V. Adams ◽  
A. Greenwood ◽  
E. Case ◽  
M. Roberts ◽  
...  
Keyword(s):  
Minute Ventilation ◽  
Face Mask ◽  
Crossover Design ◽  
Mean Difference ◽  
Inspiratory Time ◽  
Flow Rates ◽  
Thoroughbred Horses ◽  
History Of ◽  
End Tidal ◽  
Full Face

AbstractSeveral studies have shown that the placement of a face mask on a horse can have effects on ventilation, gas exchange and the cardiovascular system during exercise. The aim of the present study was to determine if airflow and ventilation measured with the same ultrasonic flowmeters were different during exercise between horses wearing half- (HM) and full-face (FM) masks. Five clinically healthy Thoroughbred horses with no history of respiratory disease were studied in an unbalanced crossover design. They were exercised on a treadmill at speeds between 1.7 and 11ms−1 on a 3° incline wearing both masks. The following variables were recorded: peak inspired (PIF) and peak expired flow rates (PEF), inspiratory tidal volume (VT), respiratory rate (fR ), inspiratory minute ventilation (VE), inspiratory time, (TI), expiratory time (TE ), total breath time (TT), end tidal oxygen (ETO2), end tidal carbon dioxide (ETCO2) and heart rate (HR). A mask by speed of exercise interaction term was not significant for any of the models. The PEF (mean difference 12.91s−1; lower and upper 95% CI 7.6 and 18.21s−1, respectively; P<0.0001) and ETO2 (mean difference 0.77%; lower and upper 95% CI 0.48 and 1.00%, respectively; P<0.0001) were significantly greater and ETCO2 was significantly lower (mean difference −1.3%; lower and upper 95% CI −2.0 and 0.7%, respectively; P<0.0001) with the FM compared with the HM. There was also a trend for inspired VE to be higher with the FM compared with the HM (mean difference 1021min−1; lower and upper 95% CI 26 and 1781 min−1, respectively; non-significant). We conclude that the HM may impair ventilation in the horse during exercise compared with the FM, despite the latter having a greater deadspace.

Effects of Varied Vocal Intensity on Ventilation and Energy Expenditure in Women and Men

1998 ◽  
Vol 41 (2) ◽  
pp. 239-248 ◽  
Author(s):  
Bridget A. Russell ◽  
Frank J. Cerny ◽  
Elaine T. Stathopoulos
Keyword(s):  
Carbon Dioxide ◽  
Steady State ◽  
Energy Expenditure ◽  
Minute Ventilation ◽  
Face Mask ◽  
Carbon Dioxide Production ◽  
Quiet Breathing ◽  
Energy Expenditures ◽  
Ventilatory Responses ◽  
End Tidal

This study was completed to determine how ventilatory responses change by means of speech reading at three different sound pressure levels (SPL) as compared to quiet breathing prior to each task. The energy required to alter SPL was also studied and compared to energy expenditures during a quiet breathing condition. Twenty-four adults (12 women, 12 men) were studied while reading a standard passage at low, comfortable, and high SPLs for 7 minutes with quiet breathing periods between each task to achieve respiratory steady state and serve as a control to which the reading tasks were compared. The last 2 minutes of exhaled air for all speaking and quiet breathing tasks were collected using a Hans Rudolph mouth breathing face mask. A Sensor Medics V max 29 TM series diagnostic instrument system measured all ventilatory responses and energy expenditures. Volume and timing alterations in ventilation were characterized by measuring tidal volume (V T ), inspiratory time (T I ), inspiratory flow rate (V T /T I ), and expiratory time (T E ). Average ventilation, energy expenditure, and adequacy of ventilation were measured using minute ventilation (V W E ), oxygen consumption V W O 2 ), carbon dioxide production (V W CO 2 ), and partial pressure of end-tidal carbon dioxide (end-tidal PET CO2 ). Results indicated volume, timing, ventilation, and energy expenditure values remained closest to quiet breathing values for the comfortable SPL. Volume, ventilation, and energy expenditure were significantly greater for the high SPL and lower for the low SPL, compared to the baseline steady state, indicating that the low SPL causes a ventilatory deficit that was found to be paid back at the end of the speech task during the quiet breathing period. These results demonstrate that an individual's comfortable SPL is the least energyrequiring way to speech breathe. As SPL rises above or below comfortable SPL, speech breathing requires more energy.

Phenylephrine-induced hypertension acutely decreases genioglossus EMG activity in awake humans

1992 ◽  
Vol 72 (1) ◽  
pp. 110-115 ◽  
Author(s):  
E. Garpestad ◽  
R. C. Basner ◽  
J. Ringler ◽  
J. Lilly ◽  
R. Schwartzstein ◽  
...  
Keyword(s):  
Minute Ventilation ◽  
Upper Airway ◽  
Face Mask ◽  
Systemic Blood Pressure ◽  
Emg Activity ◽  
Healthy Humans ◽  
Baseline Activity ◽  
Acute Changes ◽  
End Tidal ◽  
Airway Tone

To investigate the relationship between systemic blood pressure (BP) and upper airway dilator muscle activity, we recorded genioglossus electromyograms (EMGgg) during pharmacologically induced acute increases in BP in five healthy humans (ages 27–40 yr). EMGgg was measured with perorally placed fine-wire electrodes; phasic EMGgg was expressed as percentage of baseline activity. Subjects were studied supine, awake, and breathing through a face mask with their mouths taped. End-tidal PCO2 was monitored with a mass spectrometer; minute ventilation was measured with a pneumotachograph. Digital BP was monitored continuously with the Penaz method (Finapres, Ohmeda). Mean arterial pressure (MAP) at baseline was 89 +/- 6 (SD) mmHg. Phenylephrine was infused until MAP reached 15–25 mmHg above baseline (107 +/- 7 mmHg). Recording was continued until MAP returned to baseline (90 +/- 7 mmHg). Elevated BP was associated with a significantly decreased phasic EMGgg (P less than 0.005). With return of MAP to baseline, phasic EMGgg returned toward normal (P less than 0.01). Minute ventilation and end-tidal PCO2 did not differ among conditions. Genioglossus activity appears to be influenced by acute changes in systemic BP. We speculate that BP elevations accompanying obstructive apneas during sleep may decrease upper airway tone and facilitate subsequent apneas.

Respiratory instability during sleep onset

1992 ◽  
Vol 73 (6) ◽  
pp. 2462-2469 ◽  
Author(s):  
J. Trinder ◽  
F. Whitworth ◽  
A. Kay ◽  
P. Wilkin
Keyword(s):  
Minute Ventilation ◽  
Body Movement ◽  
Sleep Onset ◽  
Positive Function ◽  
Face Mask ◽  
Regulatory Control ◽  
Arousal State ◽  
State Effect ◽  
End Tidal ◽  
Respiratory Instability

It has been hypothesized that regulatory control in the respiratory system is state dependent. According to this view respiratory instability during sleep onset is a consequence of repeated fluctuations in arousal state. However, these speculations are based primarily on measurements during stable sleep, not during sleep onset itself. The aim of the present study was to assess changes in ventilation and gas tensions during sleep onset as a function of arousal state. Twenty-one subjects (12 males and 9 females, mean age 20 yr) were assessed over an average of 11.3 sleep onsets. The subject's state was classified as alpha, theta, body movement, or stage 2 sleep, and expiratory tidal volume, minute ventilation, respiratory rate, and end-tidal CO2 and O2 were measured by means of a face mask, valve, and pneumotachograph on a breath-by-breath basis. Respiratory instability during sleep onset was found to be a result of two factors. The first factor was a between-state effect in which transitions from alpha to theta were associated with falls, and from theta to alpha with increases, in ventilation. The magnitude of the change was a positive function of metabolic drive at the time of the state change (as indicated by alveolar PCO2 and PO2 levels). The second was a within-state effect in which ventilation fell during consecutive alpha breaths and increased during consecutive theta breaths. These changes were due to the influence of the relative hyperventilation of the alpha state and the relative hypoventilation of the theta state on metabolic drive.

Breathing patterns in infants and children under halothane anesthesia: effect of dose and CO2

1994 ◽  
Vol 76 (1) ◽  
pp. 79-85 ◽  
Author(s):  
O. Reich ◽  
K. Brown ◽  
J. H. Bates
Keyword(s):  
Cycle Time ◽  
Minute Ventilation ◽  
Breathing Patterns ◽  
Inspiratory Time ◽  
Halothane Anesthesia ◽  
Control Value ◽  
Co2 Rebreathing ◽  
Halothane Concentration ◽  
End Tidal ◽  
Spontaneously Breathing

We studied the amplitude, timing, and shape of the airflow waveform at the mouth of spontaneously breathing children under two sets of conditions: 1) in 30 children aged 9 wk-4.5 yr at 2, 1, and 0% inspired halothane concentration and 2) in 22 children aged 5 mo-7 yr during hyperoxic CO2 rebreathing while recovering from anesthesia. Compared with control values, the relative changes in breath parameters at 1 and 2% halothane were, respectively, as follows: total cycle time -19 and -31%, tidal volume (VT) -30 and -44%, minute ventilation -11 and -17%, and VT/inspiratory time (TI) -16 and -20%. Parameters of timing and breath shape did not change except for the significant but small increase in TI/total cycle time (by 6 and 8%, respectively). With CO2 rebreathing, parameters reflecting inspiratory drive increased significantly in all patients as shown by the slopes of the regressions of these parameters against end-tidal PCO2. Mean slopes expressed in %control value per millimeter of mercury CO2 were 12.1 for minute ventilation, 8.3 for VT, and 10.67 for VT/TI. Parameters reflecting the timing and breath shape remained essentially unchanged. Our results suggest that, in children under halothane anesthesia, the amplitude, timing, and shape of the breathing pattern are controlled independently. In particular, the amplitude and timing of the breath may vary widely without any significant change in the shape.

EX 24 Full Face Mask

1993 ◽  
Author(s):  
K. R. Jones ◽  
L. J. Crepeau
Keyword(s):  
Face Mask ◽  
Full Face

Efficacy of galcanezumab in patients with episodic cluster headaches and a history of preventive treatment failure

2021 ◽  
Vol 4 ◽  
pp. 251581632110156
Author(s):  
Brian Plato ◽  
J Scott Andrews ◽  
Mallikarjuna Rettiganti ◽  
Antje Tockhorn-Heidenreich ◽  
Jennifer Bardos ◽  
...  
Keyword(s):  
Cluster Headache ◽  
Treatment Failure ◽  
Preventive Treatment ◽  
Mean Difference ◽  
Least Square ◽  
Double Blind Study ◽  
Double Blind ◽  
Cluster Headache Attack ◽  
Episodic Cluster Headache ◽  
History Of

Objective: The efficacy of galcanezumab was evaluated in patients with episodic cluster headache and history of preventive treatment failure. Methods: In the randomized, 8-week, double-blind study (CGAL), patients with episodic cluster headache received once-monthly subcutaneous injections of galcanezumab 300 mg or placebo. Patients who completed CGAL and enrolled in an open-label study were queried for preventive treatment history. In a subset of patients with a known history of failure of verapamil or any other prior preventive treatment, a post hoc analysis of least square mean change from baseline in weekly cluster headache attack frequency across Weeks 1 to 3 was assessed. Results: Fifteen patients provided data for known history of prior preventive treatment failure (6 placebo, 9 galcanezumab), of whom 11 failed verapamil. The mean reduction in the weekly frequency of cluster headache attacks was greater with galcanezumab compared to placebo among patients with prior preventive treatment failure (8.2 versus 2.4); mean difference 5.8 (95% confidence interval [CI] 2.0, 13.6) and among patients with verapamil failure (10.1 versus 1.6); mean difference 8.5 (95% CI 0.4, 16.7). Conclusion: In this exploratory analysis of patients with a known history of prior preventive treatment failures, treatment with galcanezumab resulted in greater mean reductions in weekly cluster headache attacks compared with placebo. ClinicalTrials.gov: NCT02397473 (I5Q-MC-CGAL) NCT02797951 (I5Q-MC-CGAR)

scholarly journals Tolerability of statin-based management of patients with a history of statin-associated muscle symptoms: protocol for a systematic review

BMJ Open ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. e052341
Author(s):  
Fanny Villoz ◽  
Christina Lyko ◽  
Cinzia Del Giovane ◽  
Nicolas Rodondi ◽  
Manuel R Blum
Keyword(s):  
Systematic Review ◽  
Meta Analysis ◽  
Mean Difference ◽  
Control Group ◽  
Cochrane Central Register ◽  
Eligibility Criteria ◽  
Clinical Issue ◽  
Standard Data ◽  
Evaluation Approach ◽  
History Of

IntroductionStatin-associated muscle symptoms (SAMSs) are a major clinical issue in the primary and secondary prevention of cardiovascular events. Current guidelines advise various approaches mainly based on expert opinion. We will lead a systematic review and meta-analysis to explore the tolerability and acceptability and effectiveness of statin-based therapy management of patients with a history of SAMS. We aim to provide evidence on the tolerability and different strategies of statin-based management of patients with a history of SAMS.Methods and analysisWe will conduct a systematic review of randomised controlled trials (RCTs) and non-randomised studies with a control group. We will search in Data sources MEDLINE, EMBASE, Cochrane Central Register of Controlled Clinical Trials, Scopus, Clinicaltrials.gov and Proquest from inception until April 2021. Two independent reviewers will carry out the study selection based on eligibility criteria. We will extract data following a standard data collection form. The reviewers will use the Cochrane Collaboration’s tools and Newcastle-Ottawa Scale to appraise the study risk of bias. Our primary outcome will be tolerability and our secondary outcomes will be acceptability and effectiveness. We will conduct a qualitative analysis of all included studies. In addition, if sufficient and homogeneous data are available, we will conduct quantitative analysis. We will synthesise dichotomous data using OR with 95% CI and continuous outcomes by using mean difference or standardised mean difference (with 95% CI). We will determine heterogeneity visually with forest plots and quantitatively with I2 and Q-test. We will summarise the confidence in the quantitative estimate by using Grading of Recommendations Assessment, Development and Evaluation approach.Ethics and disseminationAs a systematic review of literature without collection of new clinical data, there will be no requirement for ethical approval. We will disseminate findings through peer-reviewed publications.PROSPERO registration numberCRD42020202619.

scholarly journals End-to-End, Pixel-Wise Vessel-Specific Coronary and Aortic Calcium Detection and Scoring Using Deep Learning

Diagnostics ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 215
Author(s):  
Gurpreet Singh ◽  
Subhi Al’Aref ◽  
Benjamin Lee ◽  
Jing Lee ◽  
Swee Tan ◽  
...  
Keyword(s):  
Deep Learning ◽  
Coronary Artery ◽  
Clinical Importance ◽  
Learning Model ◽  
Mean Difference ◽  
Interquartile Range ◽  
History Of ◽  
End To End ◽  
Artery Disease ◽  
Deep Learning Model

Conventional scoring and identification methods for coronary artery calcium (CAC) and aortic calcium (AC) result in information loss from the original image and can be time-consuming. In this study, we sought to demonstrate an end-to-end deep learning model as an alternative to the conventional methods. Scans of 377 patients with no history of coronary artery disease (CAD) were obtained and annotated. A deep learning model was trained, tested and validated in a 60:20:20 split. Within the cohort, mean age was 64.2 ± 9.8 years, and 33% were female. Left anterior descending, right coronary artery, left circumflex, triple vessel, and aortic calcifications were present in 74.87%, 55.82%, 57.41%, 46.03%, and 85.41% of patients respectively. An overall Dice score of 0.952 (interquartile range 0.921, 0.981) was achieved. Stratified by subgroups, there was no difference between male (0.948, interquartile range 0.920, 0.981) and female (0.965, interquartile range 0.933, 0.980) patients (p = 0.350), or, between age <65 (0.950, interquartile range 0.913, 0.981) and age ≥65 (0.957, interquartile range 0.930, 0.9778) (p = 0.742). There was good correlation and agreement for CAC prediction (rho = 0.876, p < 0.001), with a mean difference of 11.2% (p = 0.100). AC correlated well (rho = 0.947, p < 0.001), with a mean difference of 9% (p = 0.070). Automated segmentation took approximately 4 s per patient. Taken together, the deep-end learning model was able to robustly identify vessel-specific CAC and AC with high accuracy, and predict Agatston scores that correlated well with manual annotation, facilitating application into areas of research and clinical importance.

Sign in / Sign up

Export Citation Format

Share Document