Effect of the Physical Properties of Isoflurane, Sevoflurane, and Desflurane on Pulmonary Resistance in a Laboratory Lung Model

2006 ◽  
Vol 104 (6) ◽  
pp. 1202-1207 ◽  
Author(s):  
Vasilia G. Nyktari ◽  
Alexandra A. Papaioannou ◽  
George Prinianakis ◽  
Eytichis G. Mamidakis ◽  
Dimitris Georgopoulos ◽  
...  
Keyword(s):  
Repeated Measures ◽  
Airway Resistance ◽  
Anesthesia Machine ◽  
Lung Model ◽  
Control Mode ◽  
Volume Control ◽  
Pulmonary Resistance ◽  
Test Lung ◽  
Significant Difference ◽  
Volatile Agents

Background Airway resistance depends not only on an airway's geometry but also on flow rate, and gas density and viscosity. A recent study showed that at clinically relevant concentrations, the mixtures of volatile agents with air and oxygen and oxygen-nitrogen affected the density of the mixture. The goal of the current study was to investigate the effect of different minimum alveolar concentrations (MACs) of three commonly used volatile agents, isoflurane, sevoflurane, and desflurane, on the measurements of airway resistance. Methods A two-chamber fixed-resistance test lung was connected to an anesthesia machine using the volume control mode of ventilation. Pulmonary resistance was calculated at baseline (25% oxygen in air); at 1.0, 1.5, and 2.0 MAC; and also at the same concentrations, 1.2% and 4%, of isoflurane, sevoflurane, and desflurane mixtures with 25% oxygen in air. The analysis of variance test for repeated measures and probabilities for post hoc Tukey and least significant difference tests were used. Results Isoflurane affected pulmonary resistance only at 2 MAC. Sevoflurane caused a significant increase of pulmonary resistance at 1.5 and 2 MAC, whereas desflurane caused the greatest increase in pulmonary resistance at all MAC values used. At 1.2% concentration, no difference from the baseline resistance was observed, whereas at 4%, the three agents produced similar increases of pulmonary resistance. Conclusion High concentrations of volatile agents in 25% oxygen in air increased the density of the gas mixture and the calculated resistance of a test lung model with fixed resistance.

scholarly journals 47. Comparison of Devices Used While Ventilating a Non-Intubated Mannikin Model

1996 ◽  
Vol 11 (S2) ◽  
pp. S43-S43
Author(s):  
Glenn Updike ◽  
Vince Mosesso ◽  
Tom Auble
Keyword(s):  
Repeated Measures ◽  
Mechanical Test ◽  
Calculated Data ◽  
Minute Volume ◽  
Lung Model ◽  
Emergency Medical Technicians ◽  
Test Lung ◽  
Convenience Sample ◽  
Multiple Comparison Test

Purpose: The purpose of this study was to determine if there were differences in tidal volume (Vt), minute volume (MV), average mask leak per breath (ML), gastric insufflation (GI), and peak airway pressure (PAP) when ventilating a non-intubated mannikin with a bag-valve (BV), manually triggered ventilator (MTV) and automated ventilator (AV). Our hypothesis was that there would be no differences among devices for any of these variables.Methods: This was a prospective in vitro experimental model. A convenience sample of 19 emergency medical technicians (EMTs) ventilated a non-intubated mannikin-mechanical test lung model with BV, MTV (flow rate 40 L/min; pressure relief 55 cm H2O), and AV (800 ml/breath; rate 12). Each subject, blinded to volume and pressure gauges, used each device for two minutes at both normal (0.1 cm H2O) and poor (0.04 cm H2O) compliances. Vt, MV, GI, and PAP were measured directly and ML was calculated. Data were analyzed with repeated measures ANOVA and Bonferoni-Dunn multiple comparison test with alpha set at 0.05.

Protective Effects of Volatile Agents against Methacholine-induced Bronchoconstriction in Rats

2001 ◽  
Vol 94 (2) ◽  
pp. 348-353 ◽  
Author(s):  
Walid Habre ◽  
Ferenc Peták ◽  
Peter D. Sly ◽  
Zoltán Hantos ◽  
Denis R. Morel
Keyword(s):  
Airway Resistance ◽  
Model Fitting ◽  
Low Frequency ◽  
Tissue Mechanics ◽  
Control Group ◽  
Protective Effects ◽  
Airway Constriction ◽  
Impedance Data ◽  
Significant Difference ◽  
Volatile Agents

Background The protective properties of common volatile agents against generalized lung constriction have previously been addressed only via estimations of parameters that combine airway and tissue mechanics. Their effectiveness in preventing airway constriction have not been compared systematically. Therefore, the authors investigated the abilities of halothane, isoflurane, sevoflurane, and desflurane to provide protection against airway constriction induced by methacholine. Methods Low-frequency pulmonary impedance data were collected in open-chest rats under baseline conditions and during three consecutive intravenous infusions of methacholine (32 microg x kg(-1) x min(-1)) while the animals were anesthetized with intravenous pentobarbital (control group). Methacholine challenges were performed in four other groups of rats, first during intravenous anesthesia and then repeated during the inhalation of halothane, isoflurane, sevoflurane, or desflurane at concentrations of 1 and 2 minimum alveolar concentration (MAC). Airway resistance and inertance, parenchymal damping, and elastance were estimated from the impedance data by model fitting. Results The methacholine-induced increases in airway resistance during intravenous pentobarbital anesthesia (204 +/- 53%) were markedly and significantly (P < 0.005) reduced by 1-MAC doses of halothane (80 +/- 48%), isoflurane (112 +/- 59%), sevoflurane (68 +/- 34%), and desflurane (96 +/- 34%), with no significant difference between the gases applied. Increasing the concentration to 2 MAC did not lead to any significant further protection against the increase in airway resistance. Conclusions These data demonstrate that isoflurane, sevoflurane, and desflurane are as effective as the widely accepted halothane in protecting against methacholine-induced airway constriction.

Investigating the Effect of Cognitive-behavioral Stress Management on Occupational Performance among Women with Breast Cancer

2020 ◽  
Vol 16 (2) ◽  
pp. 152-159
Author(s):  
Arezoo Shayan ◽  
Mansoureh Refaei ◽  
Farkhondeh Jamshidi
Keyword(s):  
Breast Cancer ◽  
Stress Management ◽  
Repeated Measures ◽  
Intervention Group ◽  
Performance Measure ◽  
Cognitive Behavioral ◽  
Occupational Performance ◽  
Cognitive Behavioral Stress Management ◽  
Behavioral Stress ◽  
Significant Difference

Background: Treatment of breast cancer can be accompanied by long-term consequences affecting women’s participation in many tasks. Objective: This study aimed to assess the effect of cognitive behavioral stress management (CBSM) program on occupational performance of women with breast cancer. Methods: In this randomized clinical trial, conducted between Feb 3 and Oct 26, 2016, 104 women with breast cancer who had referred to Imam Khomeini clinic in Hamadan, and who fulfilled the inclusion criteria (20-60 years old, married, suffering from grade 1-3 breast cancer with a history of recent surgery) were enrolled. They were randomly divided into two groups of 52 using a permuted block size of four. The intervention group took part in four 60-minute sessions of CBSM over four weeks. The study data were collected using a demographic information form and the Canadian Occupational Performance Measure. The statistical analyst was masked to intervention allocation. The data were analyzed using descriptive statistics, paired t-test, and repeated measures ANOVA. Results: A significant difference was observed between the two groups regarding the mean scores of occupational performance (p=0.02) and satisfaction (p=0.005) after the intervention. Each variable was measured at three time points (before the intervention, immediately and 2 weeks after intervention). A significant difference was observed in the two groups’ mean scores of performance (p=0.026) and satisfaction (p=0.01), irrespective of the time of assessment. Conclusion: The CBSM program promoted the occupational performance immediately and two weeks after the intervention in women with breast cancer. This technique can be used as a complementary method alongside medical therapies in oncology centers.

scholarly journals Cytotoxicity assessment of different doses of ozonated water on dental pulp cells

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Ferdiye Küçük ◽  
Sibel Yıldırım ◽  
Serap Çetiner
Keyword(s):  
Cell Viability ◽  
Repeated Measures ◽  
Dental Pulp ◽  
Control Group ◽  
Dental Pulp Cells ◽  
Time Points ◽  
Significant Difference ◽  
Pulp Cells ◽  
Time Point ◽  
Ozonated Water

Abstract Background The purpose of this study was to assess the cytotoxicity of various concentrations of ozonated water (OW) on human primary dental pulp cells. Methods Human primary dental pulp cells were isolated from exfoliated primary canine teeth of an 11-year-old patient with good systemic and oral health. Afterwards, cells were divided into 6 experimental groups; four groups of OW in concentrations of 2 mg/L, 4 mg/L, 8 mg/L, and 16 mg/L, untreated control group, and cell culture without cells. Cytotoxicity was evaluated after exposure for 5-min exposure using Mosmann’s Tetrazolium Toxicity (MTT) assay at 0 h and 48 h time points. Data were analyzed using a repeated measures analysis of variance and Post-hoc tests were performed using Bonferroni correction for multiple comparisons. Results All experimental groups showed proliferation at 0 h time point. However, all groups also experienced a decrease in overtime at 48 h time point (p < 0.05). At both time points 2 mg/L OW showed the highest cell viability as well as proliferation. At 0 h time point, the increase in cell viability for all experimental groups was found statistically significant when compared to positive control group (p < 0.05). At 48 h time point, although 8 mg/L and 16 mg/L OW showed statistically significant reduction in compare to 0 h time point, 2 mg/L and 4 mg/L OW groups didn’t experience any statistically significant difference (p < 0.05). Conclusion Considering our findings, due to ozonated water's induced a higher proliferation rate of dental pulp cells, indicating their biocompatibility and a possible adjuvant on irrigating agent in regenerative endodontic procedures.

Combining Microfractures, Autologous Bone Graft, and Autologous Matrix-Induced Chondrogenesis for the Treatment of Juvenile Osteochondral Talar Lesions

2017 ◽  
Vol 38 (5) ◽  
pp. 485-495 ◽  
Author(s):  
Riccardo D’Ambrosi ◽  
Camilla Maccario ◽  
Chiara Ursino ◽  
Nicola Serra ◽  
Federico Giuseppe Usuelli
Keyword(s):  
Bone Graft ◽  
Repeated Measures ◽  
Osteochondral Lesion ◽  
Young Patients ◽  
Case Series ◽  
Autologous Bone Graft ◽  
Lesion Size ◽  
Level Of Evidence ◽  
Significant Difference ◽  
Autologous Bone

Background: The purpose of this study was to evaluate the clinical and radiologic outcomes of patients younger than 20 years, treated with the arthroscopic-talus autologous matrix-induced chondrogenesis (AT-AMIC) technique and autologous bone graft for osteochondral lesion of the talus (OLT). Methods: Eleven patients under 20 years (range 13.3-20.0) underwent the AT-AMIC procedure and autologous bone graft for OLTs. Patients were evaluated preoperatively (T0) and at 6 (T1), 12 (T2), and 24 (T3) months postoperatively, using the American Orthopaedic Foot & Ankle Society Ankle and Hindfoot (AOFAS) score, the visual analog scale and the SF-12 respectively in its Mental and Physical Component Scores. Radiologic assessment included computed tomographic (CT) scan, magnetic resonance imaging (MRI) and intraoperative measurement of the lesion. A multivariate statistical analysis was performed. Results: Mean lesion size measured during surgery was 1.1 cm3 ± 0.5 cm3. We found a significant difference in clinical and radiologic parameters with analysis of variance for repeated measures ( P < .001). All clinical scores significantly improved ( P < .05) from T0 to T3. Lesion area significantly reduced from 119.1 ± 29.1 mm2 preoperatively to 77.9 ± 15.8 mm2 ( P < .05) at final follow-up as assessed by CT, and from 132.2 ± 31.3 mm2 to 85.3 ± 14.5 mm2 ( P < .05) as assessed by MRI. Moreover, we noted an important correlation between intraoperative size of the lesion and body mass index (BMI) ( P = .011). Conclusions: The technique can be considered safe and effective with early good results in young patients. Moreover, we demonstrated a significant correlation between BMI and lesion size and a significant impact of OLTs on quality of life. Level of Evidence: Level IV, retrospective case series.

“Going Backward”: Effects of age and fatigue on posterior-directed falls in Parkinson disease

2021 ◽  
pp. 1-9
Author(s):  
Evan V. Papa ◽  
Rita M. Patterson ◽  
Nicoleta Bugnariu
Keyword(s):  
Postural Control ◽  
Parkinson Disease ◽  
Repeated Measures ◽  
Center Of Pressure ◽  
Angular Displacement ◽  
Reaction Times ◽  
Older Individuals ◽  
Peak Knee ◽  
Significant Difference ◽  
Fatiguing Exercise

BACKGROUND: Nearly half of persons with Parkinson disease (PD) report fatigue as a factor in their fall history. However, it is unknown whether these self-reported falls are caused by a sensation of fatigue or performance fatigue. OBJECTIVE: We sought to investigate the influences of performance fatigue and age on postural control in persons with PD. METHODS: Individuals with PD (n = 14) underwent postural control assessments before (T0) and immediately after (T1) fatiguing exercise. Biomechanical data were gathered on participants completing a treadmill-induced, posterior-directed fall. Performance fatigue was produced using lower extremity resistance exercise on an isokinetic ergometer. Repeated measures ANCOVAs were used with age as a covariate to determine the effects of performance fatigue on biomechanical variables. RESULTS: After adjustment for age, there was a statistically significant difference in peak center of pressure (COP) latency during the support phase of recovery. Pairwise comparisons demonstrated a decrease in peak ankle displacement from T0 to T1. Age was also found to be significantly related to reaction time and peak knee displacement while participants were fatigued. CONCLUSIONS: The decreased peak COP latency, along with decreased ankle angular displacement, suggest that persons with PD adopt a stiffening strategy in response to backward directed falls. Postural stiffening is not uncommon in persons with PD and could be a risk factor for falls. Older individuals with PD demonstrate slower mobility scores and decreased reaction times in the setting of fatigue, suggesting a combined effect of the aging and fatigue processes.

Objective assessment of nasal resistance among electronic cigarette users

2021 ◽  
pp. 1-4
Author(s):  
S W Lim ◽  
AB Zulkiflee
Keyword(s):  
Tobacco Smoking ◽  
Repeated Measures ◽  
Airway Resistance ◽  
Electronic Cigarettes ◽  
Objective Assessment ◽  
Control Group ◽  
Nasal Airway ◽  
Nasal Resistance ◽  
Short Term ◽  
Nasal Airway Resistance

Abstract Background Electronic cigarettes have been a popular alternative to tobacco smoking. The effect of tobacco smoking on nasal airway resistance has been investigated before; however, the effect of the aerosol generated by electronic cigarettes is still unknown. This study aimed to evaluate the short-term effects of e-cigarettes on nasal airway resistance. Methods Sixty-one participants were recruited into a vapers group and a control group. The vapers group was instructed to smoke for 5 minutes, and their nasal resistance was measured pre-procedure and at 1 and 5 minutes post-procedure. The results were compared between both groups. Results Repeated measures analysis of variance demonstrated that vaping has no statistically significant effect on total nasal airway resistance. Conclusion Although the differences between both groups were not statistically significant overall, the vapers group showed a reduction in nasal airway resistance in the short term.

scholarly journals Acute Comparative Effect of Foam Rolling and Static Stretching on Range of Motion in Rowers

2021 ◽  
Vol 13 (7) ◽  
pp. 3631
Author(s):  
Alfonso Penichet-Tomas ◽  
Basilio Pueo ◽  
Marta Abad-Lopez ◽  
Jose M. Jimenez-Olmedo
Keyword(s):  
Range Of Motion ◽  
Repeated Measures ◽  
Static Stretching ◽  
Foam Rolling ◽  
Significant Difference ◽  
Post Test ◽  
Alternating Treatment Design ◽  
Stroke Amplitude ◽  
Treatment Design ◽  
Over Time

Rowers’ anthropometric characteristics and flexibility are fundamental to increase stroke amplitude and optimize power transfer. The aim of the present study was to analyze the effect of foam rolling and static stretching on the range of motion over time. Eight university rowers (24.8 ± 3.4 yrs., height 182.3 ± 6.5 cm, body mass 79.3 ± 4.6 kg) participated in an alternating treatment design study with two-way repeated measures ANOVA. The sit and reach test was used to measure the range of motion. Both in the foam rolling and in the static stretching method, a pre-test (T0), a post-test (T1), and a post-15-min test (T2) were performed. A significant effect was observed on the range of motion over time (p < 0.001), but not for time x method interaction (p = 0.680). Significant differences were found between T0 and T1 with foam rolling and static stretching (p < 0.001, d = 0.4); p < 0.001, d = 0.6). The differences between T0 and T2 were also significant with both methods (p = 0.001, d = 0.4; p < 0.001, d = 0.4). However, no significant difference was observed between T1 and T2 (p = 1.000, d = 0.1; p = 0.089, d = 0.2). Foam roller and static stretching seem to be effective methods to improve the range of motion but there seems to be no differences between them.

Dentate nucleus signal intensity changes on T1-weighted MRI after repeated administrations of linear and macrocyclic gadolinium-based contrast agents: a pediatric intraindividual case-control study

2021 ◽  
pp. 028418512110188
Author(s):  
Kerem Ozturk ◽  
David Nascene
Keyword(s):  
Repeated Measures ◽  
Signal Intensity ◽  
Dentate Nucleus ◽  
Pearson Correlation ◽  
Gadopentetate Dimeglumine ◽  
Control Groups ◽  
Significant Difference ◽  
Intensity Changes ◽  
Cerebellar Peduncle ◽  
Pediatric Brain

Background An association between consecutive administrations of macrocyclic gadolinium-based contrast agent (mcGBCA) gadobutrol and linear (L)-GBCA gadopentetate dimeglumine and gadolinium retention in the pediatric brain remains incompletely understood. Purpose To compare signal intensity (SI) changes in the dentate nucleus (DN) on unenhanced T1-weighted imaging (T1WI) in children who obtained mcGBCA gadobutrol with those who had previously received L-GBCA gadopentetate dimeglumine. Material and Methods This retrospective study included 27 children who received L-GBCA gadopentetate dimeglumine followed by mcGBCA gadobutrol and two different control groups matched for age and sex for both periods, each involving 27 individuals with no GBCA administration from January 2010 to January 2020. DN-to-middle cerebellar peduncle (MCP) SI ratios on T1WI were determined. A repeated-measures ANOVA was performed to compare the T1WI SI ratio between children exposed to GBCA in each of the two periods and controls. Pearson correlation analysis was conducted to determine any correlation between SI ratios and confounding parameters. Results T1WI SI ratio was significantly higher in those who had only L-GBCA (1.005±0.087) or subsequent mcGBCA gadobutrol (1.002±0.104) than in control groups 1 (0.927±0.041; P<0.001) and 2 (0.930±0.041; P=0.002), respectively, but no significant difference of the T1WI SI ratio was noted between L-GBCA period and subsequent mcGBCA gadobutrol period ( P=0.917). T1WI SI ratios and the L-GBCA administration number revealed a modest but significant correlation (correlation coefficient=0.034; P=0.016). Conclusion Previous administration of gadopentetate dimeglumine is associated with increased T1WI SI in the DN, while subsequent administration of gadobutrol does not demonstrate any additional SI increase in the pediatric brain.

The Effects of Receiver Placement on Probe Microphone, Performance, and Subjective Measures with Open Canal Hearing Instruments

2010 ◽  
Vol 21 (04) ◽  
pp. 249-266 ◽  
Author(s):  
Lynzee N. Alworth ◽  
Patrick N. Plyler ◽  
Monika Bertges Reber ◽  
Patti M. Johnstone
Keyword(s):  
Repeated Measures ◽  
Hearing Aid ◽  
Clinical Importance ◽  
Ease Of Use ◽  
Subjective Measures ◽  
Repeated Measures Design ◽  
Hearing Instruments ◽  
Data Collection And Analysis ◽  
Significant Difference ◽  
Occlusion Effect

Background: Open canal hearing instruments differ in method of sound delivery to the ear canal, distance between the microphone and the receiver, and physical size of the devices. Moreover, RITA (receiver in the aid) and RITE (receiver in the ear) hearing instruments may also differ in terms of retention and comfort as well as ease of use and care for certain individuals. What remains unclear, however, is if any or all of the abovementioned factors contribute to hearing aid outcome. Purpose: To determine the effect of receiver location on performance and/or preference of listeners using open canal hearing instruments. Research Design: An experimental study in which subjects were exposed to a repeated measures design. Study Sample: Twenty-five adult listeners with mild sloping to moderately severe sensorineural hearing loss (mean age 67 yr). Data Collection and Analysis: Participants completed two six-week trial periods for each device type. Probe microphone, objective, and subjective measures (quiet, noise) were conducted unaided and aided at the end of each trial period. Results: Occlusion effect results were not significantly different between the RITA and RITE instruments; however, frequency range was extended in the RITE instruments, resulting in significantly greater maximum gain for the RITE instruments than the RITA instruments at 4000 and 6000 Hz. Objective performance in quiet or in noise was unaffected by receiver location. Subjective measures revealed significantly greater satisfaction ratings for the RITE than for the RITA instruments. Similarly, preference in quiet and overall preference were significantly greater for the RITE than for the RITA instruments. Conclusions: Although no occlusion differences were noted between instruments, the RITE did demonstrate a significant difference in reserve gain before feedback at 4000 and 6000 Hz. Objectively; no positive benefit was noted between unaided and aided conditions on speech recognition tests. These results suggest that such testing may not be sensitive enough to determine aided benefit with open canal instruments. However, the subjective measures (Abbreviated Profile of Hearing Aid Benefit [APHAB] and subjective ratings) did indicate aided benefit for both instruments when compared to unaided. This further suggests the clinical importance of subjective measures as a way to measure aided benefit of open-fit devices.

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