Mechanical ventilation system, effect

The airflow rate infiltrating and exfiltrating through each air leakage pass, Q , due to the combined effect of wind, stack, and mechanical ventilation system perfotmance can be calculated ftom the mass balance equation... 

Natural ventilation can be adequate provided there are sufficient vents or louvers at the ceiling or floor level. An effective design will ensure that the airflow either sweeps across the floor or ceiling continuously and adequate outside make-up air is provided. The discharge should be directed outside and away from any air inlets, other openings, and equipment such as compressors. If adequate natural ventilation cannot be provided a mechanical ventilation system should be used. Mechanical ventilation systems for applications involving transfer of flammable liquids typically have a capacity of 0.25 to 2 cfm/ft2 (0.075-0.60 m3/min/m2) and higher in trenches, sumps, or other collection areas. 

The first step in controlling potentially hazardous dusts, mists, fumes, smoke, or gases in the workplace is the installation of engineering controls such as mechanical ventilation systems. But if such measures are not fully effective (or infeasible, such as at a field work site), then respiratory PPE must be used. 

Drafts, condensation on windows, ice damming, excessive noise from outdoors or equipment operation, and rooms that are cold in winter and hot in summer will diminish comfort in a home. Air-sealed construction, improved insulation, high-performance windows, right-sized, efficient hcating/cooling distribution systems, and mechanical ventilation commonly found in energy-efficient homes all work together to effectively eliminate these problems. 

Roth B, Herkenrath P, Lehmann H-J, et al. 1988. Di-(2-ethylhexyl)-phthalate as plasticizer in PVC respiratory tubing systems Indications of hazardous effects on pulmonary function in mechanically ventilated, preterm infants. Eur J Pediatr 147 41-46. 

In a double-blind, randomized pilot study of the efficacy and adverse effects of inhaled fluticasone in 25 newborn preterm infants who required mechanical ventilation for treatment of respiratory distress syndrome, the infants were randomized to receive inhaled fluticasone 1000 micrograms/day or placebo (47). The hypothalamic-pituitary-adrenal axis was assessed by the response to corticotropin-releasing factor. AU basal and post-stimulation plasma corticotropin and serum cortisol concentrations were significantly less with inhaled fluticasone than placebo. Cumulative high-dose inhaled glucocorticoids caused moderately severe suppression of both the pituitary and the adrenal glands. This systemic activity is probably associated with pulmonary vascular absorption that avoids hepatic first-pass metabolism. 

Glasgow scale E2M4V2) with profuse oral secretions, sweating, cyanosis, muscle fasciculations and convulsions, and was intubated. Organophosphate poisoning was not suspected at first, and he was treated with dopamine and isoprenaline to increase blood pressure and heart rate and with phenytoin to control the convulsions, but all of these treatments were without effect. At 3.5 h after exposure, he was treated with 2 mg IV of atropine, which immediately increased both heart rate and blood pressure, and 10 mg IV of diazepam, which controlled the convulsions. He was maintained on continuous IV atropine (3 mg day-1) and mechanical ventilation, and 9 days after exposure he became alert and was extubated. The authors stressed the importance of systemic atropine for treating the bradycardia produced by the VX. 

Taken in proper doses, chloroquine is an extraordinarily safe drug however, its safety margin is narrow, and a single dose of 30 mg/kg may be fatal. Acute chloroquine toxicity is encountered most frequently with too rapid administration of parenteral doses. Cardiovascular effects include hypotension, vasodilation, depressed myocardial function, cardiac arrhythmias, and cardiac arrest. Confusion, convulsions, and coma denote central nervous system (CNS) dysfunction. Chloroquine doses of >5 g given parenterally usually are fatal. Prompt treatment with mechanical ventilation, epinephrine, and diazepam may be lifesaving. 

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