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Article in Korean | WPRIM | ID: wpr-716389


This paper presents a case report of tension pneumoperitoneum that occurred in a 4-month-old girl with intussusception during pneumatic reduction. Tension pneumoperitoneum is a rare but life threatening complication in air pressure enema that is commonly used to turn the intussuscepted bowel to its original position. The incidence of a simple pneumoperitoneum due to a bowel perforation associated with attempted pneumatic reduction for intussusception is as high as 4%. The simple pneumoperitoneum changed rapidly to tension pneumoperitoneum and immediate needle decompression was life-saving in this case. Similar to a tension pneumothorax, the diagnosis is clinical and management should not be delayed awaiting other confirmatory tests. The emergency physician must recognize this rare complication of pneumatic reduction and promptly treat the ensuing tension pneumoperitoneum after bowel perforation with immediate needle decompression as a part of the initial resuscitation.

Air Pressure , Decompression , Diagnosis , Emergencies , Enema , Female , Humans , Incidence , Infant , Intussusception , Needles , Pneumoperitoneum , Pneumothorax , Resuscitation
Article in English | WPRIM | ID: wpr-41398


OBJECTIVES: Patients with bilateral vocal fold paralysis (BVFP) theoretically have difficulty producing voiceless consonants. However, perceptual studies have revealed clear production of voiceless consonants with good articulation scores in nontracheostomized patients. The purpose of this study was to clarify the production of voiceless stops during articulation in patients with BVFP compared to normal speakers. METHODS: The perceptual, acoustic, and aerodynamic characteristics of patients with BVFP and those with normal speech were investigated with special reference to voiceless stop consonants. Test words were prepared to place the stop consonants in different phonological environments, and were all nonsense words. RESULTS: The patients with BVFP perceptually produced the three types of stops successfully. However, they acoustically varied voice onset time to produce phonetically representative stops but decreased voice onset time of /ph/ and /p/ compared to those of normal speakers. These patients may properly control air pressure to produce the three types of stop consonants similar to normal speakers. CONCLUSION: The patients with BVFP realized the distinctions between the three types of stops similar to the normal speakers. Although vocal mobility was absent in the patients with BVFP, voice onset time, vowel duration, closure duration, and air pressure were similar to those of normal speakers.

Acoustics , Air Pressure , Humans , Paralysis , Tracheotomy , Vocal Cords , Voice
Rev. latinoam. enferm. (Online) ; 24: e2781, 2016. graf
Article in English | LILACS, BDENF | ID: biblio-960910


ABSTRACT Objective: to analyze the scientific evidence on aerosols generated during cleaning activities of health products in the Central Service Department (CSD) and the impact of the negative pressure of the ambient air in the cleaning area to control the dispersion of aerosols to adjacent areas. Method: for this literature systematic review the following searches were done: search guidelines, manuals or national and international technical standards given by experts; search in the portal and databases PubMed, Scopus, CINAHL and Web of Science; and a manual search of scientific articles. Results: the five technical documents reviewed recommend that the CSD cleaning area should have a negative differential ambient air pressure, but scientific articles on the impact of this intervention were not found. The four articles included talked about aerosols formed after the use of a ultrasonic cleaner (an increased in the contamination especially during use) and pressurized water jet (formation of smaller aerosols 5μm). In a study, the aerosols formed from contaminated the hot tap water with Legionella pneumophila were evaluated. Conclusions: there is evidence of aerosol formation during cleanup activities in CSD. Studies on occupational diseases of respiratory origin of workers who work in CSD should be performed.

RESUMO Objetivo: analisar as evidências científicas sobre aerossóis gerados durante atividades de limpeza dos produtos para saúde no Centro de Material e Esterilização (CME) e o impacto da pressão negativa do ar ambiente na área de limpeza para controle da dispersão de aerossóis para áreas adjacentes. Método: para essa revisão sistemática de literatura foram realizadas: busca de diretrizes, manuais ou normas técnicas nacionais e internacionais indicadas por especialistas; busca no portal e bases de dados PUBMED, SCOPUS, Cinahl e Web of Science; e busca manual de artigos científicos. Resultados: Os cinco documentos técnicos analisados preconizam que na área de limpeza do CME haja diferencial negativo de pressão do ar ambiente, porém não foram encontrados artigos científicos sobre o impacto dessa intervenção. Os quatro artigos incluídos trataram dos aerossóis formados após uso de lavadora ultrassônica (aumento da contaminação principalmente durante o uso) e do jato de água pressurizado (formação de aerossóis menores que 5µm). Em um estudo foram avaliados aerossóis formados a partir de torneira de água quente contaminada com Legionella pneumophila. Conclusões: há evidências sobre formação de aerossóis durante atividades de limpeza em CME. Estudos sobre doenças ocupacionais de origem respiratória dos trabalhadores que atuam em CME devem ser realizados.

RESUMEN Objetivo: examinar la evidencia científica sobre los aerosoles generados durante las actividades de limpieza de productos de salud en el Centro de Materiales y Esterilización (CME) y el impacto de la presión negativa del aire ambiente en la zona de limpieza para controlar la dispersión de aerosoles a las zonas adyacentes. Método: para esta revisión sistemática de literatura se llevaron a cabo: búsqueda de directrices, manuales o normas técnicas nacionales e internacionales impartidas por expertos; búsqueda en las bases de datos PUBMED, SCOPUS, Cinahl y Web of Science; y búsqueda manual de artículos científicos. Resultados: Los cinco documentos técnicos analizados recomiendan que el área de limpieza del CME tenga un diferencial negativo de presión en el aire ambiente, aunque no se han encontrado artículos científicos sobre el impacto de esta intervención. Los cuatro artículos incluidos fueron sobre los aerosoles formados después del uso de la lavadora ultrasónica (aumento de la contaminación, especialmente durante el uso) y chorro de agua a presión (formación de aerosoles menores a 5µm). De esta forma, en un solo estudio se evaluaron los aerosoles formados a partir de un grifo de agua caliente contaminada con Legionella pneumophila. Conclusiones: hay evidencia de formación de aerosoles durante las actividades de limpieza en CME. Sin embargo, es necesario realizar estudios sobre las enfermedades profesionales de origen respiratorio de los trabajadores que trabajan en CME.

Ventilation , Sterilization/methods , Air Pressure , Aerosols
Article in English | WPRIM | ID: wpr-257633


<p><b>OBJECTIVE</b>To evaluate the effectiveness of two training methods for avoiding excessive inflation of laryngeal mask airway(LMA)Supreme.</p><p><b>METHODS</b>Totally 41 anesthesiologists were randomly divided into hand touch group(H group,n=20)and short-term pressure gauge training group(G group,n=21). Before training,subjects were asked to inflate the cuff of LMA Supreme to two target pressures,30 cmH(2)O and 60 cmH(2)O, according to their own experiences. The actual cuff pressures were recorded as baseline pressures. Subjects in H group then received the training of hand touch:touch the vermilion of the lip and apex nasi with the left ring finger and feel the hardness. A cuff pressure with hardness similar to the vermilion of the lip was defined as 30 cmH(2)O, and similar to the apex nasi as 60 cmH(2)O. Subjects in G group were asked to inflate the cuff with a pressure gauge and feel the hardness of the cuff when the pressure reached 30 cmH(2)O and 60 cmH(2)O. After one-week training,two groups of subjects repeated the cuff inflation test. Actual cuff pressures after training were also recorded and compared with the baseline pressures. Results Actual cuff pressures after training[Group H:(39.7±15.7) cmH(2)O(P=0.00);Group G:(26.2±13.2) cmH(2)O(P=0.03)]were significantly lower than baseline pressures in both groups when the target cuff pressure was 30 cmH(2)O, and the differences were not statistically significant between these two groups(P=0.06). When the target pressure was 60 cmH(2)O,the actual cuff pressure of H group [(91.1±24.3)cmH(2)O] was significantly higher than that of G group [(58.1±15.4) cmH(2)O (P=0.01)]. However,the actual cuff pressure of G group was similar to the target pressure.</p><p><b>CONCLUSION</b>The two training methods are equally effective when the target pressure is 30 cmH(2)O, while short-term pressure gauge training method is superior when the target pressure is 60 cmH(2)O.</p>

Air Pressure , Humans , Laryngeal Masks , Pressure
Article in Korean | WPRIM | ID: wpr-167648


PURPOSE: To compare the accuracy and reliability of intraocular pressure (IOP) measurements in enucleated porcine eyes using the Icare PRO in the upright and horizontal positions. METHODS: We designed an enucleated porcine eye model whose anterior chamber was cannulated with a 30-gauge needle, connected in parallel to a pneumatic pressure device. The reference pressure was manipulated by changing the air pressure from 70 to 10 mm Hg at 10 mm Hg intervals, and the IOP of porcine eyes was measured with the Icare PRO at each pressure. Correlation analysis, comparison using the Bland-Altman plot and Wilcoxon signed rank test, was performed to assess the accuracy of IOP measurements. Intraclass correlation coefficients were calculated to assess the intra-observer variability in the upright and horizontal positions, respectively. RESULTS: The IOP value in both upright and horizontal positions was well correlated with the reference pressure (r = 0.992 and 0.985, respectively). The Bland-Altman plot showed good agreement between the two positions. However, all IOP values in both positions were lower than the reference pressures. The IOP values in the horizontal position were significantly lower than those in the upright position at the a reference pressure of 50 mm Hg or greater. Values of intraclass correlation coefficient ranged from 0.911 to 0.984 when measured in the upright position and from 0.707 to 0.914 in the horizontal position. CONCLUSIONS: IOP measurements of Icare PRO in porcine eyes were remarkably lower than reference pressures controlled by the pneumatic method even though they showed a good correlation with reference values. The higher was the reference pressure, the greater was the degree of underestimation of IOP measurement in both positions. This trend was more pronounced in the horizontal position, and the reliability of IOP measurements was also lower than that in the upright position.

Air Pressure , Anterior Chamber , Intraocular Pressure , Iron-Dextran Complex , Needles , Observer Variation , Reference Values
Article in Korean | WPRIM | ID: wpr-157120


PURPOSE: The aim of this study was to determine whether there are monthly and seasonal variations of incidence of subarachnoid hemorrhage (SAH) in Seoul. METHODS: We conducted a cross-sectional, retrospective study on the incidence of SAH using the National Emergency Department Information System (NEDIS) of Korea, a nationwide electronic emergency medical care database. Meteorological data (daily and monthly mean sea level air pressure, daily and monthly mean air temperature, daily temperature range) between January 2010 and December 2010 in Seoul were acquired from the Korea Meteorological Administration. The incidence of SAH in patients visiting the ED was defined as those assigned the following codes of the Korea Standard Classification of Disease, 6th Revision (KCD-6codes): I600-I609. RESULTS: The diurnal variation of the onset of SAH showed two broad peak times from 10 a.m. to 2 p.m. and from 4 p.m. to 7 p.m. There was a clear seasonal variation in the occurrence rate of SAH, which was higher in winter than in any other season. Daily temperature (mean, maximum, and minimum) and mean sea-level barometric pressure were not associated with the occurrence rates of SAH. Univariate analysis showed no significant difference between bleeding days and non-bleeding days for the number of SAH patients. In multivariate analysis, the monthly mean temperature showed significant correlation with the occurrence of SAH. CONCLUSION: This study showed seasonal variation in the onset of SAH. Conduct of further population-based study would be required in order to obtain more precise and valuable information.

Air Pressure , Classification , Climate , Emergencies , Emergency Service, Hospital , Epidemiology , Hemorrhage , Humans , Incidence , Information Systems , Korea , Multivariate Analysis , Retrospective Studies , Seasons , Seoul , Subarachnoid Hemorrhage
Article in English | WPRIM | ID: wpr-329773


<p><b>OBJECTIVE</b>To investigate the impact of cuff pressure on airway leak pressure in laryngeal mask airway(LMA)Supreme and Flexible.</p><p><b>METHODS</b>Patients about to have elective breast surgery were divided into Supreme group(35 cases)and Flexible group(33 cases). After general induction of anesthesia,LMA Supreme or Flexible was inserted by one anesthesiologist. We confirmed the LMA location,adjusted the cuff pressure,and recorded the peak airway leak pressures under different cuff pressures(10,20,30,40,and 50 cmH2O).</p><p><b>RESULTS</b>In Supreme group,peak airway leak pressures [(24.46±5.43),(25.11±5.51),(25.86±5.57),(26.17±5.72)cmH2O] under 20,30,40,and 50 cmH2O cuff pressure showed no significant difference(P>0.05)between each other,but significantly higher than that under 10 cmH2O cuff pressure(20.80±4.63)cmH2O(P<0.05). And in the Flexible group,peak airway leak pressures [(20.09±2.98),(20.70±3.08),(21.21±3.15)cmH2O] under 30,40,50 cmH2O cuff pressure also showed no significant difference(P>0.05)between each other,but significantly higher than those under 10 or 20 cmH2O cuff pressure [(17.52±2.39),(18.61±2.42)cmH2O]. Mean peak airway leak pressure [(25.40±5.52) cmH2O] of LMA Supreme was significantly higher than that of LMA Flexible(20.67±3.06)cmH2O(P<0.05).</p><p><b>CONCLUSIONS</b>Mean airway leak pressure of LMA Supreme is higher than LMA Flexible. The lowest cuff pressure to meet the tightness requirement with LMA Supreme is 20 cmH2O,which is lower than Flexible(30 cmH2O).</p>

Air Pressure , Anesthesia , Methods , Humans , Laryngeal Masks , Materials Testing
Article in Chinese | WPRIM | ID: wpr-341815


In this study, solvent evaporation method was used to preparing baicalin ethylcellulose microspheres for intranasal administration. The prepared microspheres were round with certain rough surface. The average drug loading and entrapment efficiency was (33. 31 ± 0. 045)% , (63. 34 ± 0. 11)% , respectively. As the characteristic crystalline peaks of baicalin were observed in the microspheres sample, the result of X-ray diffractometric analysis indicated that the baicalin was present in crystalline form after its entrapment in ethylcellulose matrix. By investigating the thermogram of microspheres sample, it was found that endothermic peak of baicalin was shifted from 211. 8 °C to 244. 2 °C and associated with the first broad endothermic peak of ethylcellulose. This could confirm that baicalin was loaded into ethylcellulose, nor simply physical mixture. The powder flowability test exhibited that the specific energy of microspheres was 3. 57 mJ . g-1 and the pressure drop was 2. 22 mBar when air kept the speed of 2 mm . s-1 through the powder bed with the force was 15 kPa. The consequence of the baicalin in vitro released from microspheres showed that the pure baicalin sample displayed faster (90%) release than microspheres sample (75%) in 7 h. Fitting model for release curve before 7 h, the results showed that the pure baicalin sample and the microsphere sample accorded with first order model (R2 = 0. 990 4) and Riger-Peppas model(R2 = 0. 961 2), respectively. Ex vivo rabbit nasal mucosa permeability experiment revealed that the value of cumulative release rate per unit area of the microsphere sample was 1. 56 times that of the pure baicalin sample. This provided the foundation for the in vivo pharmacokinetic study.

Administration, Intranasal , Air Pressure , Animals , Cellulose , Chemistry , Drug Compounding , Methods , Flavonoids , Chemistry , Pharmacokinetics , Male , Microspheres , Mucous Membrane , Metabolism , Particle Size , Powders , Rabbits , Solvents , X-Ray Diffraction
Arq. bras. oftalmol ; 76(5): 278-281, set.-out. 2013. ilus, tab
Article in English | LILACS | ID: lil-690604


PURPOSE: To study the deformation response of three distinct contact lenses with known structures, which served as corneal models, under different chamber pressures using ultra-high-speed (UHS) Scheimpflug imaging. METHODS: Three hydrophilic contact lenses were mounted on a sealed water chamber with precisely adjustable pressure: TAN-G5X (41% hydroxyethylmethacrylate/glycolmethacrylate, 550 µm thick), TAN-40 (62% hydroxyethylmethacrylate, 525 µm thick) and TAN-58 (42% methylmethacrylate, 258 µm thick). Each model was tested five times under different pressures (5, 15, 25, 35 and 45 mmHg), using ultra-high-speed Scheimpflug imaging during non-contact tonometry. 140 Scheimpflug images were taken with the UHS camera in each measurement. The deformation amplitude during non-contact tonometry was determined as the highest displacement of the apex at the highest concavity (HC) moment. RESULTS: At each pressure level, the deformation amplitude was statistically different for each lens tested (p<0.001, ANOVA). Each lens had different deformation amplitudes under different pressure levels (p<0.001; Bonferroni post-hoc test). The thicker lens with less polymer (TAN-G5X) had a higher deformation (less stiff behavior) than the one that was thinner but with more polymer (TAN-40), when measured at the same internal pressure. The thinnest lens with less polymers (TAN-58) had a lower deformation amplitude (stiffer behavior) at higher pressures than the thicker ones with more polymer (TAN-40 and TAN-G5X) at lower pressures. CONCLUSIONS: UHS Scheimpflug imaging allowed for biomechanical assessment through deformation characterization of corneal models. Biomechanical behavior was more influenced by material composition than by thickness. Chamber pressure had a significant impact on deformation response of each lens.

OBJETIVO: Estudar a resposta de deformação de três lentes de contato com estruturas conhecidas, que serviram como modelos de córnea, recorrendo à imagem de Scheimpflug de alta velocidade. MÉTODOS: Três lentes de contato hidrófilas foram montadas em uma câmara de água selada com pressão ajustável: TAN-G5X (41% hidroxietilmetacrilato/glycolmethacrylate, 550µm de espessura), TAN-40 (hidroxietilmetacrilato 62%, 525 µm de espessura) e TAN-58 (42% metilmetacrilato, 258 µm de espessura). Cada modelo foi testado cinco vezes sob pressões diferentes (5, 15, 25, 35 e 45 mmHg), recorrendo a um tonómetro de não-contato acoplado a uma câmara de Scheimpflug de alta velocidade. Cento e quarenta imagens de Scheimpflug foram capturadas em cada medição. A amplitude de deformação foi determinada como o maior deslocamento do ápice no momento de maior concavidade do modelo testado. RESULTADOS: Em cada nível de pressão, a amplitude de deformação foi estatisticamente diferente para cada lente testada (p<0,001, ANOVA). Cada lente teve amplitude de deformação diferente sob distintos níveis de pressão (p<0,001; Bonferroni teste post-hoc). A lente mais espessa e com menos polímero (TAN-G5X) apresentou maior deformação (comportamento menos rígido) do que aquela que era mais fina mas com mais polímero (TAN-40), quando testadas sob a mesma pressão. A lente mais fina e com menos polímero (TAN-58) apresentou uma menor amplitude de deformação (comportamento mais rígido) sob pressões mais elevadas, em comparação com as lentes mais grossas e com mais polímero (TAN-40 e TAN-G5X) em pressões mais baixas. CONCLUSÕES: A imagem de Scheimpflug de alta velocidade permite uma avaliação biomecânica através da medição da amplitude de deformação dos modelos de córnea. O comportamento biomecânico foi mais influenciado pela composição do que pela espessura da lente. A pressão da câmara apresentou um impacto significativo sobre a amplitude de deformação de cada lente.

Air Pressure , Contact Lenses/standards , Cornea/physiology , Image Processing, Computer-Assisted/methods , Models, Biological , Analysis of Variance , Biomechanical Phenomena , Cornea/surgery , Corneal Pachymetry/methods , Manometry/methods
Article in Chinese | WPRIM | ID: wpr-322356


<p><b>OBJECTIVE</b>To introduce a modified model for quantitative testing of glucose microleakage by constant air pressure and evaluate the sealing ability of four root canal sealers including AU Plus, Roeko Seal, Cortisomol and RC Sealer.</p><p><b>METHODS</b>Fifty-six straight maxillary anterior teetb were randomly divided into four experimental groups with 12 samples in each group, group A: AH Plus, group B: Roeko Seal, group C: Cortisomol, group D: RC Sealer, and positive and negative control group with 4 samples in each. After regular root preparation, samples in experimental groups were obturated by cold gutta-percha lateral compaction technique with sealers according to group description. Control groups were obturated with cold gutta-percha only. Through the model above, the value of glucose microleakage from crown to root was measured at 1, 3, 5, 7, 10, 15, 20, 25, 30 days with the glucose oxidase-peroxidase method (GOD-POD).</p><p><b>RESULTS</b>At day 1, 3, 5, no significant difference of microleakage was found between group A and B (P > 0.05). The same result was also seen between group C and D. From 7 days, microleakage value in each experimental group gradually increased, and statistical difference was found between groups (P < 0.05).</p><p><b>CONCLUSION</b>This new model using constant air pressure is easy to establish, sensitive and practical. Among all the sealers evaluated, polydimethylsiloxane based root canal sealer, Roeko Seal has the greatest sealing ability, while epoxy-amine resin based AH Plus is second and Zinc Oxide based Cortisomol and RC Sealer have the least sealing ability.</p>

Air Pressure , Dental Cements , Dental Leakage , Dental Pulp Cavity , Epoxy Resins , Glucose , Gutta-Percha , Humans , Root Canal Filling Materials , Zinc Oxide-Eugenol Cement
Article in Chinese | WPRIM | ID: wpr-246545


Oxygen enrichment of room air is an effective way to resist hypoxia at high altitude, but it may introduce a potential fire hazard. In common, the burning rate of light and thin homogeneous solid in oxygen enriched atmosphere was used to assess the fire hazard. For the purpose of measuring the burning rate of light and thin homogeneous solid in oxygen enriched atmosphere, we used the methods of laser contact ignition and direct calculation of burning rate, and invented a device that includes mixing gas system, ignition equipment, system of measuring the burning rate and self-made specimen frame. By using the homemade device, we studied the burning rate of filter paper under low pressure and in oxygen-enriched atmosphere and in that of the oxygen concentration of reached stationary burning rate. The results showed that this device was simple, and could obtain the burning rate of light and thin homogeneous solid quantitatively.

Air Pressure , Altitude , Atmosphere Exposure Chambers , Environment, Controlled , Equipment Design , Fires , Oxygen
J. appl. oral sci ; 19(5): 505-510, Sept.-Oct. 2011. ilus, tab
Article in English | LILACS | ID: lil-600841


OBJECTIVES: The purpose of this study was to investigate the effect of different air-polishing powders on the color stability of different types of composite resin restorative materials. MATERIAL AND METHODS: Thirty cylindrical specimens (15×2 mm) were prepared for each of 7 composite resin restorative materials. All specimens were polished with a series of aluminum oxide polishing discs (Sof-Lex). The prepared specimens of each composite resin were randomly divided into 3 groups of 10 specimens each, for control (Group-C) and two air-powder applications (Group-CP: Cavitron Prophy-Jet; Group-PS: Sirona ProSmile prophylaxis powder). A standard air-polishing unit (ProSmile Handly) was used. All specimens were air-powdered for 10 s at 4-bar pressure. The distance of the spray nosel from the specimens was approximately 10 mm and angulation of the nosel was 90°. Specimens were stored in 100 mL of coffee (Nescafe Classic) for 24 h at 37°C. Color measurement of all specimens was recorded before and after exposure to staining agent with a colorimeter (Minolta CR-300). Color differences (∆E*) between the 2 color measurements (baseline and after 24 h storage) were calculated. The data were analyzed with a 2-way ANOVA test, and mean values were compared by the Tukey HSD test (p<0.05). RESULTS: According to the 2-way ANOVA results, composite resin restorative materials, air-polishing powders, and their interaction were statistically significant (p<0.05) For Aelite Aesthetic Enemal, Filtek Z250, Grandio, CeramX Mono, and Quixfil composite resin restorative materials, no significant difference was observed between Group-PS and Group-CP (p>.05) and these groups demonstrated the highest ∆E* values. For Filtek Silorane and IntenS, the highest ∆E* values were observed in Group-PS. The lowest ∆E* values for all composite resin groups were observed in Group-C. When comparing the 7 composite resin restorative materials, Aelite Aesthetic Enemal demonstrated significantly less ∆E* values than the other composite resins tested. The highest ∆E* values were observed in Quixfil. CONCLUSION: Except for Quixfil, all control groups of composite resins that were polished Sof-Lex exhibited clinically acceptable ∆E values (<3.7). Air-polishing applications increased the color change for all composite resin restorative materials tested. Composite restorations may require re-polishing after air-polishing.

Color , Composite Resins/chemistry , Dental Polishing/methods , Air Pressure , Analysis of Variance , Aluminum Oxide/chemistry , Colorimetry , Materials Testing , Powders , Prosthesis Coloring , Random Allocation , Surface Properties , Time Factors
Article in Korean | WPRIM | ID: wpr-106042


PURPOSE: The purpose of this study was to identify the effects of cuff pressure on postoperative sore throat. METHODS: Data were collected from January 4 through May 15, 2008. Among the 60 patients, 30 patients were randomly assigned to the control group and the rest to the experimental group. Initial cuff pressure of both groups was set at 20 cmH2O. The experimental group was maintained at 20 cmH2O throughout the anesthesia, while the control group was not regulated further. Sore throat was assessed at postoperative 1, 24 and 72 hours. Data were analyzed using Mann-Whitney U test and Spearman's rho coefficients. RESULTS: Cuff pressure in the control group increased from 20 to 43 cmH2O within 3 hours after induction. However, the experimental group showed that there was apparently a reduced rate of sore throat at postoperative 24 hours (p = .048), and 72 hours (p = .002) than in the control group. However, no outstanding differences between both groups at postoperative 1 hour (p = .081) were detected. The correlation between cuff pressure and sore throat was statistically significant (r(s) = .590, p < .001). CONCLUSION: We conclude that maintaining cuff pressure at 20 cmH2O could be an effective means to reduce sore throat in surgical patients with inhalation anesthesia.

Air Pressure , Anesthesia , Anesthesia, Inhalation , Humans , Intubation, Intratracheal , Nitrous Oxide , Pharyngitis
Acta cir. bras ; 22(5): 396-400, Sept.-Oct. 2007. ilus, tab
Article in English | LILACS | ID: lil-463465


PURPOSE: To assess the sterilization effectiveness on uterine tube of rabbit by the cyanoacrylate adhesive. METHODS: Hysteroscopy tubal catheterization was performed randomly in 12 animals (24 uterine tubes) assigned to the sham group (GS) and 15 animals (30 uterine tubes) to the n-butyl-cyanoacrylate (GB). The female rabbits were observed during 30, 90 and 180 days and mated to fertile males. The no pregnant rabbits were submitted to in vitro burst pressure test for patency by air insufflation (40 mmHg). The microscopic assessment was performed to parameters of damages in epithelium caused by the adhesive, the degree of inflammatory process, morphometry data values of tube diameter (UT) (cm), mucosa thickness (MT) and the myosalpinx thickness (MyT) (mm). The mucosa cells densitometry (total optical density) was expressed by the amount of DNA. The significance of the differences in histological scores and in thickness measurements were made by ANOVA test (P value < 0.05). RESULTS: In all animals of GB: the adhesive was attached to the mucosa; there was no pregnancy; no records of significant degree on inflammatory process; the patency test was negative and densitometry of DNA showed similar values to the both groups independently of observation periods. The layers thickness of GB-UT(1.118±0.117), GB-MT(0.447±0.247) and GB-MyT(0.853±0.097) were larger than the GS-UT(0.666±0.409), GS-MT(0.211±0.070) and GS-MyT(0.442±0.143). CONCLUSION: This approach offers a safe and feasible method of uterine tube obstruction.

OBJETIVO: Verificar a eficácia do adesivo de cianoacrilato na esterilização de tubas uterinas de coelhas. MÉTODOS: A cateterização tubária por histeroscopia foi realizada randomicamente em 12 animais (24 tubas uterinas) formando o Grupo Sham (GS) e 15 animais (30 tubas uterinas) para o grupo do n-butil-cianoacrilato (GB). As coelhas foram observadas por 30, 90 e 180 dias e acasaladas com machos férteis. As tubas uterinas das fêmeas que não ficaram grávidas foram submetidas ao teste de pressão de rompimento in vitro, com insuflação de ar (40mmHg). A microscopia óptica estudou os danos causados ao epitélio pelo adesivo, o grau de processo inflamatório, a morfometria do diâmetro tubário (UT) (cm), da mucosa (MT) e do miosalpinge (MyT) (mm). A densitometria das células da mucosa (Densidade Optica Total) foi expressa pela contagem do DNA. As significâncias dos diferentes escores histológicos e das medidas das camadas foram avaliadas pelo Teste de ANOVA (P<0,005). RESULTADOS: Em todos os animais do GB: o adesivo estava aderido na mucosa tubária, não ocorreu prenhez, não houve significância nos graus do processo inflamatório, o teste de perviedade foi negativo e a densitometria do DNA apresentou valores similares em todos os grupos, independente do período de observação. A medida das camadas do GB-UT(1.118±0.117), GB-MT(0.447±0.247) e GB-MyT (0.853±0.097) foi maior que as dos GS-UT(0.666±0.409), GS-MT(0.211±0.070) e GS-MyT(0.442±0.143). CONCLUSÃO: O procedimento proposto foi de fácil execução e eficaz para obstrução da tuba uterina de coelhas.

Animals , Female , Pregnancy , Rabbits , Cyanoacrylates/therapeutic use , Fallopian Tubes , Hysteroscopy , Sterilization, Tubal/methods , Tissue Adhesives/therapeutic use , Air Pressure , Analysis of Variance , Densitometry , Fallopian Tubes/anatomy & histology , Fallopian Tubes/surgery , Models, Animal , Pregnancy Rate , Random Allocation , Sterilization, Tubal/adverse effects
J. bras. pneumol ; 33(3): 255-262, maio-jun. 2007. ilus, tab
Article in Portuguese | LILACS | ID: lil-461987


OBJETIVO: A criação de um modelo mecânico que pudesse ser regulado para simular o condicionamento do ar inspirado e expirado nos mesmos valores normais de temperatura, pressão e umidade relativa do aparelho respiratório de um homem jovem hígido sob ventilação mecânica. MÉTODOS: Utilizando-se diversos tipos de materiais, um aparelho mecânico foi construído e regulado com valores normais de capacidade vital, volume corrente, pressão inspiratória máxima, pressão expiratória final positiva e temperatura do gás dentro do sistema. O aparelho foi submetido a ventilação mecânica por um período de 29,8 min. A cada dois segundos, foram registradas as alterações de temperatura do ar circulado no sistema. RESULTADOS: Mediante análise estatística dos dados coletados observou-se que o aparelho construído foi eficiente no condicionamento do ar aproximadamente nos moldes do aparelho respiratório de um ser humano. CONCLUSÃO: Ao final deste estudo, conseguiu-se desenvolver um aparelho mecânico capaz de simular o condicionamento do ar respirado nas mesmas condições de temperatura, pressão e umidade do aparelho respiratório de um ser humano hígido.

OBJECTIVE: To create a mechanical model that could be regulated to simulate the conditioning of inspired and expired air with the same normal values of temperature, pressure, and relative humidity as those of the respiratory system of a healthy young man on mechanical ventilation. METHODS: Using several types of materials, a mechanical device was built and regulated using normal values of vital capacity, tidal volume, maximal inspiratory pressure, positive end-expiratory pressure, and gas temperature in the system. The device was submitted to mechanical ventilation for a period of 29.8 min. The changes in the temperature of the air circulating in the system were recorded every two seconds. RESULTS: The statistical analysis of the data collected revealed that the device was approximately as efficient in the conditioning of air as is the respiratory system of a human being. CONCLUSION: By the study endpoint, we had developed a mechanical device capable of simulating the conditioning of air in the respiratory tract. The device mimics the conditions of temperature, pressure, and relative humidity seen in the respiratory system of healthy individuals.

Adult , Humans , Male , Air , Models, Anatomic , Respiratory System , Respiration, Artificial/instrumentation , Ventilators, Mechanical , Air Pressure , Humidity , Respiration, Artificial/standards , Temperature , Total Lung Capacity
Säo Paulo med. j ; 125(1): 9-14, Jan. 2007. tab, graf
Article in English | LILACS | ID: lil-449882


CONTEXT AND OBJECTIVE: Thoracic epidural anesthesia (TEA) following thoracic surgery presents known analgesic and respiratory benefits. However, intraoperative thoracic sympathetic block may trigger airway hyperreactivity. This study weighed up these beneficial and undesirable effects on intraoperative respiratory mechanics. DESIGN AND SETTING: Randomized, double-blind clinical study at a tertiary public hospital. METHODS: Nineteen patients scheduled for partial lung resection were distributed using a random number table into groups receiving active TEA (15 ml 0.5 percent bupivacaine, n = 9) or placebo (15 ml 0.9 percent saline, n = 10) solutions that also contained 1:200,000 epinephrine and 2 mg morphine. Under general anesthesia, flows and airway and esophageal pressures were recorded. Pressure-volume curves, lower inflection points (LIP), resistance and compliance at 10 ml/kg tidal volume were established for respiratory system, chest wall and lungs. StudentÆs t test was performed, including confidence intervals (CI). RESULTS: Bupivacaine rose 5 ± 1 dermatomes upwards and 6 ± 1 downwards. LIP was higher in the bupivacaine group (6.2 ± 2.3 versus 3.6 ± 0.6 cmH2O, p = 0.016, CI = -3.4 to -1.8). Respiratory system and lung compliance were higher in the placebo group (respectively 73.3 ± 10.6 versus 51.9 ± 15.5, p = 0.003, CI = 19.1 to 23.7; 127.2 ± 31.7 versus 70.2 ± 23.1 ml/cmH2O, p < 0.001, CI = 61 to 53). Resistance and chest wall compliance showed no difference. CONCLUSION: TEA decreased respiratory system compliance by reducing its lung component. Resistance was unaffected. Under TEA, positive end-expiratory pressure and recruitment maneuvers are advisable.

CONTEXTO E OBJETIVO: Os benefícios pós-operatórios da anestesia peridural torácica (APT) na analgesia e respiração após toracotomias são conhecidos. Contudo, bloqueio simpático torácico pode desencadear hiperreatividade das vias aéreas. Este estudo pesou tais efeitos benéficos e indesejáveis na mecânica respiratória intra-operatória. TIPO DE ESTUDO E LOCAL: Estudo clínico, randomizado, duplo-cego realizado em hospital público terciário. MÉTODOS: Uma tabela de números aleatórios dividiu 19 pacientes submetidos a ressecção pulmonar parcial entre duas soluções administradas na APT: ativa (15 ml 0,5 por cento bupivacaína, n = 9) ou placebo (15 ml 0,9 por cento NaCl, n = 10). Ambas continham epinefrina 1:200,000 e morfina 2 mg. Sob anestesia geral, pressões esofágicas e de vias aéreas foram registradas. Curvas de pressão versus volume, pontos de inflexão inferior (PII), resistências e complacências sob volume corrente de 10 foram aferidos para sistema respiratório, parede torácica e pulmões. O teste t de Student foi realizado (p < 0,005), incluindo intervalos de confiança (IC). RESULTADOS: A dispersão cefálica e caudal da bupivacaína foi, respectivamente, de 5 ± 1 e de 6 ± 1 dermátomos. A curva PII foi maior no Grupo Bupivacaína (6,2 ± 2,3 versus 3,6 ± 0,6 cm H2O, p = 0,016, IC = -3,4 a -1,8). Complacências do sistema respiratório e pulmões foram maiores no Grupo Placebo (respectivamente 73.3 ± 10.6 versus 51.9 ± 15.5, p = 0,003, IC = 19,1 a 23,7, e 127,2 ± 31,7 versus 70,2 ± 23,1 H2O-1, p < 0,001, IC = 61 a 53). Resistências e complacências da parede torácica não mostraram diferenças. CONCLUSÃO: APT diminui a complacência do sistema respiratório por reduzir seu componente pulmonar. Resistências não são afetadas. Sob APT, pressão positiva expiratória final e manobras de recrutamento são recomendáveis.

Humans , Male , Female , Adult , Middle Aged , Autonomic Nerve Block/adverse effects , Bupivacaine/adverse effects , Lung Compliance/physiology , Respiratory Mechanics/physiology , Air Pressure , Anesthesia, Epidural , Airway Resistance/drug effects , Airway Resistance/physiology , Bupivacaine/administration & dosage , Double-Blind Method , Esophagus/drug effects , Esophagus/physiology , Forced Expiratory Volume , Lung Compliance/drug effects , Lung/drug effects , Lung/physiology , Lung/surgery , Monitoring, Intraoperative , Positive-Pressure Respiration , Respiratory Mechanics/drug effects , Tidal Volume/drug effects , Tidal Volume/physiology
Article in Chinese | WPRIM | ID: wpr-253408


<p><b>AIM</b>To study changes of function of transmitter glycine in nitrogen narcosis.</p><p><b>METHODS</b>Synaptosomes of rat spinal cord were prepared. Glycine uptake of synaptosomes of rat spinal cord in 0.7 MPa (7ATA) hyperbaric air pressure was observed by the methods of isotope.</p><p><b>RESULTS</b>Glycine uptake slowed down and took a longer period of time to reach saturation in 0.7 MPa (7ATA). The maximum glycine uptake was lessened. Vm was diminished, but Km was increased. Vm rose in 0.7 MPa (7ATA) when corticosterone was added.</p><p><b>CONCLUSION</b>When nitrogen narcosis arose in 0.7 MPa (7ATA), the function of transporters of glycine re-uptake was reduced, the affinity of glycine for transporters subsided. Corticosterone was conductive to the recovery of the function of glycine transporters of high affinity.</p>

Air Pressure , Animals , Glycine , Metabolism , Rats , Rats, Sprague-Dawley , Spinal Cord , Metabolism , Synaptosomes , Metabolism
Rev. chil. enferm. respir ; 22(3): 181-188, sep. 2006. tab, graf
Article in Spanish | LILACS | ID: lil-453805


To keep a pressure that allows human life, commercial airplanes need to pressurize their cabins, which mean an equilibration between the fuselage structure, the fuel consumption and the operational costs. In this condition they can only maintain cabin pressures of a simulated altitude of 8,000 feet. The Dalton´s law indicates that the inspired partial pressure of oxygen is severely reduced, meaning a real hypoxic condition for humans. Another physical modifications that take place in this artificial media, such as low air humidity and reduced vital capacity because of abdominal gas decompression. These alterations are well tolerated by normal individuals, but this is not the case for chronic respiratory patients. They suffer a severe deterioration of their oxygenation. There are only limited studies about patients in these conditions. On the other hand, control has not been obligatory and the decision to allow the flight depends on the pulmonary physician´s advice or on the patient´s own decision. In this article we discuss general concepts about this merging problem and describe some rational ways to evaluate these patients based on available information.

La necesidad de que los aviones comerciales presuricen su cabina para mantener presiones compatibles con la vida, requiere equilibrar la estructura del fuselaje, el consumo de combustible y el costo operacional, limitaciones que sólo permiten mantener presiones de cabina correspondientes a 8.000 pies (2.438 m). Según la ley de Dalton, esta altura sobre el nivel del mar implica una acentuada disminución de la presión inspirada de oxígeno, situación de hipoxia real para el ser humano. Otras alteraciones de este medio artificial afectan también la respiración normal, como la humedad ambiental de un 20 por ciento y la disminución de la capacidad vital por descompresión del gas abdominal. Estos cambios, habitualmente bien tolerados por un individuo normal, no lo son para pacientes con patología respiratoria crónica, en quienes se ha demostrado profundo deterioro de la oxigenación. Los estudios al respecto son limitados y basados en restringidas series de casos. Por otro lado, el control de este aspecto no ha sido obligatorio, por lo que la decisión de aconsejar el vuelo en avión en un paciente, depende del criterio de su médico o bien de la propia decisión del paciente. En este artículo presentamos conceptos generales de este problema emergente y planteamos algunas líneas racionales de evaluación.

Humans , Child , Adult , Aerospace Medicine , Pulmonary Disease, Chronic Obstructive/physiopathology , Travel , Air Pressure , Aircraft , Altitude , Hypoxia/physiopathology , Hypoxia/therapy , Oxygen Consumption/physiology , Pulmonary Disease, Chronic Obstructive/therapy , Lung Diseases/physiopathology , Oxygen Inhalation Therapy , Predictive Value of Tests , Blood Pressure/physiology , Respiratory Function Tests/methods
Rev. bras. anestesiol ; 56(3): 287-303, maio-jun. 2006. ilus
Article in Portuguese | LILACS | ID: lil-430830


JUSTIFICATIVA E OBJETIVOS: Para a partição das medidas de mecânica do sistema respiratório em seus componentes pulmão e parede torácica, faz-se necessário o conhecimento da pressão pleural. A finalidade desta revisão foi discutir sobre medidas alternativas à obtenção da pressão pleural para o cálculo da mecânica pulmonar, relatar as peculiaridades do método do balão esofágico para obtenção indireta da pressão pleural, as particularidades da obtenção da medida da pressão esofágica em pacientes sedados ou anestesiados, discorrer sobre a medida direta da pressão pleural e sua correlação com a pressão esofágica, assim como relatar sobre o reflexo da PEEP nas pressões pleural e esofágica. CONTEUDO: A variação da pressão intra-esofágica reflete a variação da pressão intrapleural, podendo ser usada como medida alternativa à pressão pleural direta, no estudo da mecânica dos componentes pulmão e parede do sistema respiratório. A medida da pressão esofágica pode ser realizada por meio de um delicado balão posicionado no interior do esôfago. O método e a técnica foram observados e validados em seres humanos e animais em diferentes condições e posturas corporais. O emprego da PEEP em pacientes sob ventilação controlada mecânica está consolidado; no entanto, existem controvérsias da correlação próxima entre a pressão esofágica e a pressão pleural em pacientes ventilados com PEEP, o que pode resultar em erros de cálculo de mecânica respiratória considerando a pressão esofágica. CONCLUSÕES: O método do balão esofágico é o mais utilizado para a obtenção da medida indireta da pressão pleural. Em pacientes sedados ou anestesiados sem alterações significativas da complacência respiratória, a variação da pressão esofágica corresponde à variação da pressão pleural quando a PEEP é aplicada.

Humans , Air Pressure , Catheterization , Esophagus/physiology , Respiratory Mechanics/physiology , Positive-Pressure Respiration , Pleura/physiology , Respiration, Artificial