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At least 145 records · Page 8Linked to original sources
PubMed1993

[The effect of the ventilation rate on the air particle and air microbe concentration in operating rooms with conventional ventilation. 2. Measurement during surgical activity with respect to surgical personnel number and surgical activity phases].

For measurements with surgical activity, it was investigated if the air-exchange-rate has a significant influence on airborne particle and bacteria concentrations in two conventionally ventilated operating theatres. Next to that the influence of number of personnel in the operating theatre and the various operating phases were calculated (explanation of variance). Statistical differences were found for airborne particle concentrations and a few for airborne bacteria concentrations in supply and ambient air. From the hygienic point of view these differences must be considered to be irrelevant because of the little margin (less than one lg-step) between the values. The comparison of all air-exchange-rates as well as that between the two air-exchange-rates in the two operating theatres show that the number of personnel present in the operating theatre has the most influence on airborne particle concentrations variance. Concerning airborne bacteria concentrations explanation of variance by the treatment factors air-exchange-rate, personnel and operating phase is negligible. Summarizing the low (7.5 and 10/h) and high (15 and 20/h) air-exchange-rates did not increase the explanation of variance for airborne particle and bacteria concentrations although the differences were on a significant level.

Air Microbiology↗
PubMed1986

The use of the Reuter centrifugal air sampler for the estimation of bacterial air counts in different hospital locations.

The convenience and portability of the Reuter centrifugal air sampler (RCS) encouraged us to determine a range of 'expected values' for bacterial air counts in nine hospitals at 13 defined locations. Results were recorded as the number of cfu per strip per 4 min. Bacterial air counts were comparable from hospital to hospital; in operating theatres the overall median RCS counts for air-inlets and in empty operating rooms were 13 and 9.8 cfu per strip per 4 min respectively. For surgical wards the median value was 141 and 180 cfu per strip per 4 min with, and without, air conditioning. Increased counts were readily demonstrated during surgical operations, and during bedmaking in wards. Conversion of RCS counts to cfu m-3 of air usually yielded values higher than those established by other methods. Our findings, however, demonstrate that this instrument may replace some of the applications of the slit sampler and facilitate examination of epidemiological problems.

Air Microbiology↗
PubMedDate not supplied

The Air Medical Leadership Congress: setting the health care agenda for the air medical community.

BACKGROUND: Emergency air medical transport provides the means for critically ill or injured patients to rapidly access sophisticated medical flight teams and medical centers. However, issues such as surging emergency medical services helicopter accidents, expected pilot and nurse shortages, falling reimbursements, and new compliance regulations are now threatening these important but expensive transport services. Unless an industry strategy can be developed to address these and other threats, many medical flight programs may be forced to curtail the availability of these lifesaving services. PURPOSE: On September 4-6, 2003, air medical leaders, experts, program managers, providers, and users of emergency air medical services gathered in Salt Lake City, Utah, to discuss and formulate recommendations to address the top issues that threaten the future of air medical transport services. This congress was open to anyone engaged in the field of air medical transport. This historic meeting resulted in a plan to enhance transport safety, foster appropriate utilization, improve in-flight medical care, maximize cost and reimbursement effectiveness, and develop strategies to reduce the adverse effects of new regulatory and compliance mandates. OBJECTIVES: This article describes the significance of the Air Medical Leadership Congress and the 10-Point Plan method used to develop it.

Air Ambulances↗
PubMed2000

The biofiltration of indoor air: implications for air quality.

An alternative method of maintaining indoor air quality may be through the biofiltration of air recirculating within the structure rather than the traditional approach of ventilation. This approach is currently being investigated. Prior to its acceptance for dealing with volatile organic compounds (VOCs) and CO2, efforts were made to determine whether the incorporation of this amount of biomass into the indoor space can have an (negative) impact on indoor air quality. A relatively large ecologically complex biofilter composed of a ca. 10 m2 bioscrubber, 30 m2 of plantings and a 3,500 litre aquarium were established in a 160 m2 'airtight' room in a recently constructed office building in downtown Toronto. This space maintained ca. 0.2 air changes per hour (ACH) compared to the 15 to 20 ACH (with a 30% refresh rate) of other spaces in the same building. Air quality parameters of concern were total VOCs (TVOCs), formaldehyde and aerial spore counts. TVOC and formaldehyde levels in the biofilter room were the same or significantly less than other spaces in the building despite a much slower refresh rate. Aerial spore levels were slightly higher than other indoor spaces but were well within reported values for 'healthy' indoor spaces. Levels appeared to be dependent on horticultural management practices within the space. Most genera of fungal spores present were common indoors and the other genera were associated with living or dead plant material or soil. From these results, the incorporation of a large amount of biomass associated with indoor biofilters does not in itself lower indoor air quality.

Air Pollution, Indoor↗
PubMed1992

[Are humidity filters necessary in the inspired air in the breathing circuit? A new in vivo method of measuring humidity in the air breathed].

Humidification of inspiratory gases under anaesthetic conditions still is a matter of controversial discussion. Physiological humidification and heating of breathing air are preconditions for mucociliary clearance, pulmonary cleaning and defence mechanisms. These functions of the upper respiratory tract are eliminated by application of artificial airways. In general the humidification of inspiratory gases should not remain under 70% of relative air humidity at 37 degrees C. Under clinical conditions it is problematic to ensure sufficiently rapid and reproducible measurements of humidity during breathing cycles. We developed a measuring method that enables to make these measurements without big mechanical device. Aim of this investigation was to measure air humidity in typical semiclosed systems during anaesthesia and semiopen CPAP-respiration. The necessity and efficiency of a heat and moisture exchanger (HME) was to be investigated as well. After approximately 5 minutes there was an inspiratory relative air humidity not below 70% at 28 degrees C (19 mg H2O/l humid air) within the breathing circuit with CO2 double-absorber. By using an HME it is possible to increase relative air humidity within this system to 86% at 29.5 degrees C (25 mg/l). After one hour's respiration with this system without HME a relative humidity of 87% at 30 degrees C (26 mg/l) is reached after replaced HME. Initial relative humidity in a semiopen CPAP-system is about 12% at 28 degrees C (3 mg/l). This is increased to 85% at 29.5 degrees C (25 mg/l) after 15 minutes respiration with HME.(ABSTRACT TRUNCATED AT 250 WORDS)

Air↗
PubMed1994

Detection of site of air entry in venous air embolism: role of Valsalva maneuver.

Venous air embolism in posterior fossa surgery is a well-documented complication. Various highly sensitive devices help in early detection of air embolism. In management of air embolism, sealing the site of air entry is an important step in preventing further episodes. Here we discuss the importance of inspiratory hold after lung inflation (Valsalva maneuver) in helping to localize the site of air entry and its role in the management of venous air embolism observed in two cases of posterior fossa mass, operated in sitting position.

Astrocytoma↗
PubMed1991

Efficacy of an air-cleaning device equipped with a high efficiency particulate air filter in house dust mite respiratory allergy.

The efficacy of an air-cleaning device equipped with a high efficiency particulate air (HEPA) filter (without further avoidance measures) was studied in patients allergic to house dust mite. The effects of the air-cleaner on indoor Dermatophagoides sp. levels, symptom score and bronchial hyperresponsiveness in nine mite-allergic patients were assessed using a cross-over controlled study. No significant effect was demonstrated on indoor Dermatophagoides sp. levels when comparing the period of air-cleaner activity (2 months) with the control period (2 months). The Dermatophagoides sp. levels in the houses studied were lower than the risk level for asthmatic attacks, making it difficult to assess any effect on asthma; however, neither bronchial hyperresponsiveness nor rhinitis symptom score were changed by air-cleaner activity. During the trial period, however the mean level of Dermatophagoides sp. allergen in the houses changed spontaneously from 4.4 micrograms/g (mean level in the first 2 trial months) to 1.75 micrograms/g of dust (second 2 months) (P less than 0.05). Owing to this change, the mean rhinitis symptom score also decreased (P less than 0.05), even if no significant correlation was demonstrated (r = 0.4 P = 0.089). HEPA filter air-cleaners appear insufficient as substitutes for standard avoidance measures in mite allergic patients.

Adolescent↗
PubMed2003

The link between symptoms of office building occupants and in-office air pollution: the Indoor Air Pollution Index.

The lack of an effective indoor air quality (IAQ) metric causes communication concerns among building tenants (the public), building managers (decision-makers), and IAQ investigators (engineers). The Indoor Air Pollution Index (IAPI) is developed for office buildings to bridge this communication discord. The index, simple and easily understood, employs the range of pollutant concentrations and concentrations in the subject building to estimate a unitless single number, the IAPI, between 0 (lowest pollution level and best IAQ) and ten (highest pollution level and worst IAQ). The index provides a relative measure of indoor air pollution for office buildings and ranks office indoor air pollution relative to the index distribution of the US office building population. Furthermore, the index associates well with occupant symptoms, percentage of occupants with persistent symptoms. A tree-structured method is utilized in conjunction with the arithmetic mean as the aggregation function. The hierarchical structure of the method renders not only one index value, but also several sub-index values that are critical in the study of an office air environment. The use of the IAPI for IAQ management is illustrated with an example. The decomposition of the index leads to the ranking of sampled pollutants by their relative contribution to the index and the identification of dominant pollutant(s). This information can be applied to design an effective strategy for reducing in-office air pollution.

Air Pollution, Indoor↗
PubMed1997

Respiratory health and long-term exposure to air pollutants in Swiss schoolchildren. SCARPOL Team. Swiss Study on Childhood Allergy and Respiratory Symptoms with Respect to Air Pollution, Climate and Pollen.

The impact of long-term exposure to air pollution on respiratory and allergic symptoms and illnesses was assessed in a cross-sectional study of schoolchildren (ages 6 to 15 yr, n = 4,470) living in 10 different communities in Switzerland. Air pollution measurements (particulate matter less than 10 microns in diameter [PM10], nitrogen dioxide [NO2], sulfur dioxide [SO2], and ozone) and meteorologic data were collected in each community. Reported symptom rates of chronic cough, nocturnal dry cough, and bronchitis, adjusted for individual risk factors, were positively associated with PM10, NO2, and SO2. The strongest relationship was observed for PM10 (adjusted odds ratios for chronic cough, nocturnal dry cough, and bronchitis between the most and the least polluted community for PM10 were 3.07 [95% CI: 1.62 to 5.81], 2.88 [95% CI: 1.69 to 4.89], and 2.17 [95% CI: 1.21 to 4.89], respectively). The high correlation between the average concentrations of the pollutants makes the assessment of the relative importance of each pollutant difficult. No association between long-term exposure to air pollution and classic asthmatic and allergic symptoms and illnesses was found. There was some indication that frequency of fog is a risk factor of chronic cough and bronchitis, independent of air pollution. In conclusion, this study provides further evidence that rates of respiratory illnesses and symptoms among children augment with increasing levels of air pollution even in countries like Switzerland with moderate average air pollution concentrations.

Adolescent↗
PubMed1990

Role of ventilation, air filtration, and allergen production rate in determining concentrations of rat allergens in the air of animal quarters.

Concentration of any substance in the air of a room is determined by the ratio between the rates of its production and removal. Thus, high concentrations can result from high production, low removal, or a combination of the two. Air filtration can supplement ventilation in removing allergens from the air. Control of aeroallergen exposure at any particular location would be more rational and effective if the contribution of production, ventilation, and filtration were known. Using immunochemical assays for rat urinary protein allergen, we measured the rate of production by individual rats and the concentration of allergens in the air of rat animal quarters where the ventilation rate was about 15 changes per hour. We introduced two different high-efficiency filtration systems that provided additional clean air changes up to a maximum of 127 changes per hour. Male rats shed about 20 ng/min of allergen. Because of this high rate of production, substantial reduction in rooms that housed large numbers of animals required the very high air-exchange rates that were achieved with laminar flow small animal isolator racks. Measured concentrations agreed well with concentrations calculated from a mass balance equation whose terms included numbers of animals in the room, production rate by individual animals, and rates of ventilation and filtration. We suggest that this principle of considering both production and removal rates applies not only to devising means of reducing levels of rat allergens in rat rooms, but generally to other indoor allergens as well.

Air Pollutants, Occupational↗
PubMedDate not supplied

[The monitoring of air pollution in a hospital environment using quantitative air biology methods].

The methodology of quantitative aerobiological control is described and the results of measurements of the intensity and character of air contamination are commented for several places of general surgical ward. The importance of such a control is stressed in the context of general efforts to improve the quality of air in hospitals, to prevent air contamination and decrease the incidence of aerogenic infections. The results of those measurements show that the intensity of air contamination is corresponding to the total volume of physical activity in a milieu. In some very delicate hospital areas (dressing units and operating theatres), the concentration of aerosol sometimes exceeds its permitted level and if this is a case, it is advised to take all possible measures of protection to prevent air contamination and aerogenic infections. It is also found out that at the very beginning of physical activity, there is predominance of relatively big aerosol fractions in air, but soon this predominance is diminished because of the elimination of those fractions by sedimentation.

Air Microbiology↗
PubMed1989

Bunegin-Albin catheter improves air retrieval and resuscitation from lethal venous air embolism in upright dogs.

Three types of catheters, the Arrow multi-orifice catheter, the American Edwards 7 Fr Swan-Ganz catheter and the Cook Bunegin-Albin multi-orifice CVP catheter were evaluated for their ability to retrieve venous air emboli and effect on the success rate of resuscitation from venous air emboli. The catheters were inserted in dogs anesthetized with isoflurane (1.7%, inspired) and N2O (66%) in O2 and placed in the sitting position with the head 90 degrees to the horizontal. Swan-Ganz catheters were positioned with the right atrial (RA) port just above the junction of the superior vena cava (SVC) and the RA and the pulmonary artery (PA) port in the pulmonary artery. The Arrow and Bunegin-Albin multi-orifice catheters were placed with the proximal orifice just above the SVC-RA junction and the distal orifice near the mid-RA. Dogs were then given a predetermined lethal dose of air (5 ml.kg-1) over 30 sec via the jugular vein. Attempts to aspirate venous air emboli were begun with the first decrease in expired CO2. Both RA and PA ports of the Swan-Ganz catheter were used for aspiration. The amounts of gas retrieved expressed as a percent of the injected air and the incidence of successful resuscitation were compared. Significantly greater percentages of injected venous air were retrieved with the Bunegin-Albin catheter (63 +/- 14%, mean +/- SEM) than with the Arrow multi-orifice catheter (6 +/- 2%) or the Swan-Ganz catheter (14 +/- 5%).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1987

Bunegin-Albin catheter improves air retrieval and resuscitation from lethal venous air embolism in dogs.

Three types of catheters, the single-orifice Sorenson CVP kit catheter, the right atrial (RA) port of an American Edwards 7F Swan-Ganz catheter, and the Cook Bunegin-Albin multi-orifice CVP catheter were evaluated for their ability to retrieve venous air emboli and effect on the success rate of resuscitation from venous air emboli. The catheters were inserted in anesthetized dogs in the prone position. Swan-Ganz catheters were positioned with the RA port just above the junction of the superior vena cava (SVC) and the RA, single-orifice Sorensen catheters with the orifice tip located either just above the SVC-RA junction or in the mid-RA, and Bunegin-Albin multiorifice catheters with the proximal orifice just above the SVC-RA junction and the distal orifice near the mid-RA. Dogs were then given a predetermined lethal dose of air (5 ml/kg) over 30 sec via the femoral vein. Attempts to aspirate venous air emboli were begun with first decrease in expired CO2. The amounts of air retrieved and the incidence of successful resuscitation were compared. Significantly greater percentages of injected venous air were retrieved with the Bunegin-Albin catheter (60 +/- 7%) than with the Sorenson catheter in the SVC (16 +/- 6%), with the Sorenson catheter in the mid-RA (10 +/- 3%) or with the Swan-Ganz RA port (4 +/- 1%). Resuscitation was significantly more often successful with the Bunegin-Albin catheter (six of nine dogs) than with either Sorenson catheter (zero of seven in both groups) or the Swan-Ganz RA port (one of seven).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMedDate not supplied

Residential air exchange rates for use in indoor air and exposure modeling studies.

Data on air exchange rates are important inputs to indoor air quality models. Indoor air models, in turn, are incorporated into the structure of total human exposure models. Fragmentary data on residential ventilation rates are available in various governmental reports, journal articles, and contractor reports. Most of the published papers present data on only a few homes to answer very specialized questions, and none of these publications summarize the ventilation rates of a large population of homes across the United States. Brookhaven National Laboratory (BNL) has conducted more than 4000 residential perfluorocarbon tracer (PFT) measurements and brought them together into a large data base from about 100 studies in the United States and elsewhere. This paper analyzes the BNL PFT data base to generate frequency distributions and summary statistics for different regions of the United States, different seasons, and different levels within the homes. The data analyses suggest that residential ventilation rates are similar in the northeastern and northwestern states but higher in the southwestern states. Winter and fall ventilation rates are similar, but the rates are slightly higher in spring, and much higher in summer. Multi-level residences have higher air exchange rates than single-level residences. Although the BNL data are not a representative sample of homes in the United States, these analyses give insight into the range of air exchange rates found in the United States under a great variety of conditions and are intended for use by developers of models of indoor air quality and total human exposure.

Air Pollution, Indoor↗
PubMed2004

Ultraclean air for prevention of postoperative infection after posterior spinal fusion with instrumentation: a comparison between surgeries performed with and without a vertical exponential filtered air-flow system.

STUDY DESIGN: This study retrospectively compared infection rates between adult patients after posterior spinal instrumentation procedures performed in a conventional versus an ultraclean air operating room. OBJECTIVE: To evaluate if the use of ultraclean air technology could decrease the infection rate after posterior spinal arthrodesis with instrumentation. SUMMARY OF BACKGROUND DATA: Postoperative wound infection after posterior arthrodesis remains a feared complication in spinal surgery. Although this frequent complication results in a significant problem, the employment of ultraclean air technology, as it is commonly used for arthroplasty, has not been reported as a possible alternative to reduce the infection rate after complex spine surgery. METHODS: One hundred seventy-nine patients having posterior spinal fusion with instrumentation were divided into 2 groups: group I included 139 patients operated in a conventional operating room, and group II included 40 patients operated in a vertical laminar flow operating room. Patient selection was performed favoring ultraclean air technology for elective cases in which high infection risk was considered. A statistical analysis of the infection rate and its associated risk factors between both groups was assessed. RESULTS: We observed 18 wound infections in group I and 0 in group II. Comparison of infection rates using the chi-squared test showed a statistically significant difference (P <0.017). CONCLUSION: The use of ultraclean air technology reduced the infection rate after complex spinal procedures and appears to be an interesting alternative that still needs to be prospectively studied with a randomized protocol.

Adolescent↗
PubMed1994

Clearing the air: the links between occupational and environmental air pollution control.

We reviewed the relationship between occupational respiratory medicine and the environmental health aspects of air pollution control. Although these fields share epidemiologic and toxicologic concerns, they collaborate infrequently. From an historical perspective, both occupational health and air pollution control efforts increased in response to the Industrial Revolution but only occasionally overlapped. Moreover, they were undermined by the belief in "bad air" as the cause of epidemic disease. In the twentieth century, occupational medicine and industrial hygiene professionals together addressed mass air pollution exposure incidents, but this period of interdisciplinary activity was brief. Later regulatory approaches, together with economic pressures, have tended to divide rather than integrate occupational and environmental health. Despite their differences, these disciplines are linked by common scientific challenges. Recent governmental and non-governmental efforts suggests that future efforts in occupational health and air pollution control may become better coordinated.

Air Pollutants↗