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At least 451 records · Page 25Linked to original sources
PubMed1982

[Simultaneous monitoring of skin, sublingual, esophageal and rectal temperature of intubated patients in an air conditioned operating room. A comparison of methods].

The body temperature of 36 patients of ages 20-83 years, who were undergoing abdominal and extra-abdominal surgery, was measured oesophageally, sublingually, rectally and on the skin during a period of 2 h. The question behind this was: how far can the changes in deep body temperature (represented by the oesophageal temperature) be assessed by methods other than those applied oesophageally. The body temperature sank statistically distinctly, continually and, depending on the chosen method of measuring, by an average of 1.12 degrees C (oesophageal and rectal), 0.99 degrees C (sublingual) and 0.78 degrees C (skin) respectively. The sublingual temperature proved to be the best assessor of deep body temperature. With its help, 91.6% of the variance of oesophageal temperature in the mean was explainable.

Adult↗
PubMed1999

Buildings operations and ETS exposure.

Mechanical systems are used in buildings to provide conditioned air, dissipate thermal loads, dilute contaminants, and maintain pressure differences. The characteristics of these systems and their operations h implications for the exposures of workers to environmental tobacco smoke (ETS) and for the control of these exposures. This review describes the general features of building ventilation systems and the efficacy of ventilation for controlling contaminant concentrations. Ventilation can reduce the concentration of ETS through dilution, but central heating, ventilating, and air conditioning (HVAC) can also move air throughout a building that has been contaminated by ETS. An understanding of HVAC systems is needed to develop models for exposures of workers to ETS.

Air Conditioning↗
PubMed2003

Shutting down operating theater ventilation when the theater is not in use: infection control and environmental aspects.

OBJECTIVE: In hospital operating rooms (ORs), specially conditioned air is supplied to protect patients from airborne agents that may cause infections. This study investigated whether it is hygienically safe to shut down the air supply at night if measures are taken to ensure a timely restart before surgery is performed. DESIGN: Experimental study. SETTING: Neurosurgical OR of a German university hospital. METHODS: The ventilation system was switched off and restarted after 10 hours. Particles suspended in the air near the operating table were counted, OR temperature was measured, and settle plates were exposed and incubated. RESULTS: In 13 investigations, a median of 1.3 x 10(4) particles 0.5 microm/m3 or greater (range, 5.8 x 10(3) to 1.1 x 10(5)) were documented immediately after restart in the morning. After 10 minutes and subsequently, no test showed a particle count exceeding the threshold limit of 1.0 x 10(4) particles 0.5 microm/m3 or greater recommended by the German Society of Hygiene and Microbiology. Only a few colony-forming units (CFU) were detected per settle plate (median, 0 CFU/60 cm2; range, 0 to 8) and OR temperatures quickly reached normal levels. CONCLUSIONS: Shutting down OR ventilation during off-duty periods does not appear to result in an unacceptably high particle count or microbial contamination of the OR air shortly after the system is restarted. Because substantial energy and cost savings are likely, this should be considered in hygienically safe heating, ventilation, and air conditioning systems. However, normal ventilation should be established at least 30 minutes before surgical activity.

Academic Medical Centers↗
PubMed1984

Nasal physiology.

Because injudicious surgery may adversely alter nasal function, those who treat problems of the nose should be aware of nasal physiology. The nose has seven functions: airway, air conditioning, air cleaning, olfaction, phonation, reflex, and secondary sex organ. These are reviewed in detail and their significance to the planning and performance of an aesthetic rhinoplasty, septal surgery, and turbinate surgery appropriately noted. Form and function are related.

Cilia↗
PubMed2002

Characterization of Pseudomonas spp. associated with spoilage of gilt-head sea bream stored under various conditions.

The population dynamics of pseudomonads in gilt-head sea bream Mediterranean fish (Sparus aurata) stored under different conditions were studied. Phenotypic analysis and sodium dodecyl sulfate-polyacrylamide gel electrophoresis of whole-cell proteins were performed to identify a total of 106 Pseudomonas strains isolated from S. aurata stored under different temperatures (at 0, 10, and 20 degrees C) and packaging conditions (air and a modified atmosphere of 40% CO(2)-30% N(2)-30% O(2)). Pseudomonas lundensis was the predominant species, followed by Pseudomonas fluorescens, while Pseudomonas fragi and Pseudomonas putida were detected less frequently. Fluorescent Pseudomonas strains dominated under air conditions, while proteolytic and less lipolytic strains dominated under modified-atmosphere packaging. Different storage conditions appear to govern the selection of pseudomonads in gilt-head sea bream fish.

Animals↗
PubMed2006

Improving performance of HVAC systems to reduce exposure to aerosolized infectious agents in buildings; recommendations to reduce risks posed by biological attacks.

The prospect of biological attacks is a growing strategic threat. Covert aerosol attacks inside a building are of particular concern. In the summer of 2005, the Center for Biosecurity of the University of Pittsburgh Medical Center convened a Working Group to determine what steps could be taken to reduce the risk of exposure of building occupants after an aerosol release of a biological weapon. The Working Group was composed of subject matter experts in air filtration, building ventilation and pressurization, air conditioning and air distribution, biosecurity, building design and operation, building decontamination and restoration, economics, medicine, public health, and public policy. The group focused on functions of the heating, ventilation, and air conditioning systems in commercial or public buildings that could reduce the risk of exposure to deleterious aerosols following biological attacks. The Working Group's recommendations for building owners are based on the use of currently available, off-the-shelf technologies. These recommendations are modest in expense and could be implemented immediately. It is also the Working Group's judgment that the commitment and stewardship of a lead government agency is essential to secure the necessary financial and human resources and to plan and build a comprehensive, effective program to reduce exposure to aerosolized infectious agents in buildings.

Advisory Committees↗
PubMed2004

Treatment of nasal inflammation decreases the ability of subjects with asthma to condition inspired air.

We previously showed that individuals with seasonal allergy have a reduced ability to condition air, which was improved by nasal inflammation. We also showed that subjects with asthma have a reduced ability to condition air. Because individuals with asthma usually have inflammation in the nose, we hypothesized that treatment with an intranasal steroid would reduce nasal inflammation and further decrease nasal conditioning capacity. We performed a randomized, double blind, placebo-controlled, 2-way crossover study on 20 subjects with asthma comparing the effect of treatment with intranasal budesonide for 2 weeks on nasal conditioning. Treatment with budesonide caused no significant effect on nasal conditioning as compared with placebo. When we evaluated the subgroup of nonsmoking subjects, budesonide caused a significant reduction in nasal conditioning. We speculate that nasal inflammation in nonsmoking individuals with asthma increases the conditioning capacity and reducing it with an intranasal steroid worsens the ability of the nose to condition air. In addition, smoking causes an increase in nasal conditioning capacity by non-steroid-dependent factors. These observations help us understand the pathophysiology of nasal conditioning, but do not negate the positive clinical benefits of budesonide on treating nasal inflammation.

Administration, Intranasal↗
PubMed2005

Determining the frequency of open windows in residences: a pilot study in Durham, North Carolina during varying temperature conditions.

Air pollution exposures in the residential microenvironment can be significantly affected by air exchange rate (AER). A number of studies have shown that AER in residences is significantly affected by the number and location of open windows and doors. A pilot study was conducted in Durham, North Carolina, to determine whether useful data on open windows and doors could be acquired through a visual survey. The study consisted of 72 2-h survey sessions conducted between October 24, 2001 and March 13, 2003. During the first hour of each session, a technician selected a set of corner residences in one of 48 census tracts and completed a survey form and meteorological measurements for each residence. During the second hour, the technician revisited each residence surveyed during the first hour. The resulting database included data on 2200 "residential visits" (1100 residences times two visits per residence). The technician observed one or more open windows during 20.0 percent of the residential visits. One or more open doors were observed during 13.4 percent of the residential visits; 28.2 percent of the residential visits were associated with at least one open window or door. A series of stepwise linear regression analyses were performed on the data to identify factors associated with open windows and doors. Results of these analyses indicated that the likelihood of one or more windows being opened tended to increase under the following conditions: occupancy at time of visit; session during April, May, or June; high population or housing density; window air conditioning (AC) units; absence of AC; large number of doors; and wind speed above 2 mph. The likelihood of open doors tended to increase under the following conditions: occupancy at time of visit; residence within city limits; session during April, May, or June; detached one-story residence; large number of doors; high housing density; school out; and residence within 10 m of road. Transition probabilities (closed to open and open to closed) were determined for windows and doors by time of day.

Air Conditioning↗
PubMed1991

Influence of water content of inspired air during and after exercise on induced bronchoconstriction.

This study looked at the influence of inspired air water content on exercise-induced bronchospasm (EIB). On separate days, 12 mild asthmatics (4M, 8F), aged 18-39 yrs (mean: 27 yrs), performed four six minute steady-state exercises on ergometer at 80% of their maximum workload. Exercises were randomized to the following inspired air conditions: dry air (0% relative humidity (RH] during exercise followed by dry (DD) or humid air (100% RH) (DH) after exercise, humid air during exercise followed by dry (HD) or humid air (HH). Room temperature was kept constant (22 +/- 1 degree C) at all visits. Forced expiratory volume in one second (FEV1) was measured before and every 5 min for 25 min after exercise. Ventilation (VE) was not significantly different whether the exercise was done under dry or humid air. There was a residual bronchodilatation at the end of exercises performed in humid air, while at this time FEV1 was already lower than baseline when exercise was done in dry air conditions. The maximal fall in FEV1(%) following exercise was significantly greater after those performed in dry air: DD (29 +/- 5.6%) and DH (30 +/- 5.8%) than in humid air: HD (12 +/- 4.9%) and HH (20 +/- 4.9%) (p less than 0.05). The time-course of recovery from bronchoconstriction was significantly improved when inhaling dry air after exercise. However, the difference found in the maximal % fall in FEV1 after exercise when recovery was in dry compared to humid air did not achieve statistical significance. In conclusion, EIB is influenced by the changes in water content during and after exercise. Bronchoconstriction following exercise is minimal if exercise is done in humid air and recovery in dry air, and maximal if the exercise is performed in dry air and recovery in humid air.

Adolescent↗
PubMed2004

Nasal conditioning in perennial allergic rhinitis after nasal allergen challenge.

BACKGROUND: Antigen challenge in seasonal allergic rhinitis is considered to be associated with an increased ability of the nose to condition inspired air. In contrast, little is known about air conditioning after antigen challenge in perennial allergic rhinitis (PAR). OBJECTIVE: The aims of this study were to investigate whether antigen challenge in PAR changes nasal air conditioning and to assess the relationship between nasal conditioning and nasal patency and geometry. METHODS: Nineteen subjects with PAR were enrolled into this study. Measurement of nasal conditioning, active anterior rhinomanometry (AAR), acoustic rhinometry (AR), and clinical symptom evaluation were performed before and after nasal allergen challenge with allergen extracts from house dust mites. RESULTS: Ten and 20 min after nasal allergen challenge, the total water content of the air measured in the nasopharynx and the water gradient across the nose were significantly higher in the nasal cavity in which the allergen extract was sprayed. The temperature on both sides of the nose increased non-significantly after nasal allergen challenge. No correlation to data obtained by AAR, AR, and clinical symptom evaluation after nasal allergen challenge was found. CONCLUSION: We suggest that an increase in mucosal humidity due to the allergic provocation might be responsible for the increase in nasal conditioning capacity because no correlation to changes in nasal perimeter and patency was found.

Adaptation, Physiological↗
PubMed2003

Commuter exposure to aromatic VOCs in public transportation modes in Hong Kong.

This study investigated commuter exposure to aromatic volatile organic compounds (VOCs) in different commuting microenvironments. In Hong Kong, more than 90% of the local citizens rely on public transport facilities in their daily commutes. During five winter months in late 2001 and early 2002, in-vehicle monitoring was performed in nine popular public transportation modes: tram, public light bus, air-conditioned bus, non-air-conditioned bus, taxi, ferry and three railway systems (Mass Transit Railway-MTR, Kowloon-Canton Railway-KCR and Light Rail Transit-LRT). These transports were grouped into three categories: railway transport, roadway transport and marine transport. Air samples of benzene, toluene, ethylbenzene and m/p/o-xylene were collected by canisters and analysed by gas chromatography and mass selective detector technique. Results indicated that the in-vehicle VOC exposure levels were greatly influenced by the mode of transport. For benzene, mean concentration ranged from 4.8 to 6.1 microg x m(-3) in roadway transports, 3.0-3.8 microg x m(-3) in railway transports and it was 2.1 microg x m(-3) in ferry. Regardless of the results in MTR and air-conditioned buses, the VOC levels in roadway transport were the highest and was followed by railway transport. The exposure levels in marine transport were the lowest. The TEX concentrations were found to be substantially higher in air-conditioned buses and MTR trains than in other transports, suggesting the existence of additional solvent-related sources in their vehicle interiors. Measurements in non-air-conditioned double deck vehicles indicate that there was slightly higher VOC levels in the lower deck than in the upper deck microenvironment. The average upper to lower deck exposure ratio ranged from 0.79 to 0.87 in trams and 0.78-0.83 in non-air-conditioned buses, depending on the compound of concern. The VOC exposure levels of public transport commuters in Hong Kong are far lower than those in most oversea cities. The experimental concentrations obtained in this study are within the relevant health-protecting limits as stated in the Hong Kong Indoor Air Quality Objective. Influences of recent VOC pollution control measures and local traffic characteristics on in-vehicle level are discussed.

Air Pollution, Indoor↗
PubMed1996

Elevated symptom prevalence associated with ventilation type in office buildings.

The California Healthy Building Study was designed to assess relations between ventilation system type and office worker symptoms in a set of U.S. buildings selected without regard to worker complaints. Twelve public office buildings in northern California meeting specific eligibility criteria were studied in the summer of 1990: three naturally ventilated, three mechanically ventilated (without air conditioning), and six air-conditioned buildings. Questionnaire data were collected from 880 workers in selected spaces within the study buildings. We adjusted effect estimates for various ventilation types for personal, job, and work place factors using logistic regression, and alternatively, using a mixed effects model (SAS/GLIMMIX) to adjust for correlated responses within study spaces. Higher adjusted prevalences of most symptom outcomes were associated with both mechanical and air-conditioned ventilation, relative to natural. With a conservative adjustment for problem building status, the highest adjusted prevalence odds ratios from logistic regression models were for dry or itchy skin [mechanical: odds ratio (OR) = 6.0, 95% confidence interval (CI) = 1.6-22; air-conditioned: OR = 6.0, 95% CI = 1.7-21] and lower respiratory symptoms (mechanical: OR = 2.9, 95% CI = 0.7-11; air-conditioned: OR = 4.0, 95% CI = 1.1-15). GLIMMIX estimates were similar, with slightly wider confidence intervals. Reporting bias was small. These findings of symptom increases within mechanically ventilated and air-conditioned U.S. buildings support previous findings available only from European buildings.

Adult↗