Respiratory volume

Blood Skeletal muscle Respiratory volume activity activity... 

You maybe asked for the definitions above, and to explain them clearly it is often useful to refer to a diagram. You will be expected to be familiar with a diagram of normal respiratory volumes against time, and to be able to explain its main components. 

A margin of exposure of 2 has been selected as a basis for distinguishing scenarios that are of concern from those which are unlikely to be of concern. Consequently, for inhalation of solids, the GEVs are corresponding to an intake of 25, 500, and 5000 pg/person/day for high, medium, and low hazard category, respectively, based on a respiratory volume of lOm /day. 

WHO standard values for respiratory volumes (average figures) are those recommended by the International Commission on Radiological Protection (ICRP 1974 - cited in WHO/IPCS 1994, 1999). These values are shown in Table 7.1. 

Experimental inhalation data are normally derived from standardized studies in which animals are at rest. Human workers are expected to have a higher respiratory rate because they are in a status of elevated activity. Consequently, in calculating the inhalatory DNEL for workers, the respective dose descriptor of the inhalation study needs to be adjusted to take into account the elevated respiratory volume in workers. 

It may occur that the exposure route of the dose descriptor does not correspond to the exposure route of the DNEL. Therefore, the dose descriptor needs to be corrected in terms of a route-to-route-extrapolation. For example, if an inhalatory dose descriptor (expressed in mg/m ) serves as starting point for the derivation of an oral DNEL (expressed in mg/kg body weight), the basal respiratory volume for the relevant species (e.g., in rats 1.15 mVkg body weight/24 h) is used to correct the dose descriptor in terms of the estimated total daily... 

H healthy males Inhalation 1-8 10 min (through face mask) At 5 ppm, subjects complained of dryness in throat and upper respiratory passages 1-8 ppm, decreased respiratory volume and increased respiratory rate were noted Aindur et aL 1953... 

Theoretical dose calculated from respiratory volume, LCtso, and estimated percent retention. 

Rabbit 234 d Gavage - not specifi Resp 14722 (Decrease respiratory rate. Increase respiratory volume) Seegal 1927 NH4CL q X m n m... 

The consumption of oxygen is decreased an inconsequential 5-7% with 20-30 mg. subcutaneously, and respiratory volume does not ordinarily change significantly (1). 

Tyramine (p-hydroxyphenethylamine) was isolated in 1909 by Barger and Dale (176) from Claviceps purpurea (ergot) and also by Henze (184) from the salivary gland of cephalopods. It provokes a salivary secretion, a contraction of the piloerectors, a mydriasis, and a slowing of the pulse rate in the dog (185). In the cat (0.06 g. subcutaneously) there can be noted, in addition, a motor stimulation, a respiratory excitation, and a hyperthermia (186), and in rats there is an increase in the respiratory volume (0.01-0.1 g. subcutaneously (187)). Bry (173) confirms the respiratory stimulation which tyramine provokes. 

Bock (192) wrote of the older experiments, especially those of Impens (193) which established the respiratory stimulating effects of caffeine. The latter author does not consider caffeine as a respiratory analeptic because it only slightly increases the respiratory rate (10 mg./kg. in the rabbit) and hardly affects the respiratory volume. 

The analeptic action of theophylline-diethanolamine is much less effective in the rabbit than that of theophylline-ethylenediamine. Diethanolamine scarcely modifies the respiratory rate and amplitude but it slightly increases the total respiratory volume. This phenomenon is seen equally with or without denervation of the chemoceptors of the carotid sinuses (200). 

Theobromine stimulates the respiration of the dog depressed by pheno-barbital, being more active than caffeine. The increase in the respiratory volume per minute is 38.4% for 10 mg./kg. of theobromine, and 15.8% for the same dosage of caffeine (206). 

The respiratory volume of different animal species correlates very well with the body weight, so no division by the body weight is necessary for determining the substance-specific toxic behavior. 

Several timed respiratory volumes describe the ability of the respiratory system to move air. Among these are forced vital capacity (PNC), forced expiratory volume in t seconds (FEV,), the maximum ventilatory... 

Carbon Dioxide - COj, 124-38-9 nonflammable, asphyxiant sublimes at -78.5"C [-109"F] er = NA sp g = 1.53 PEL = 5000 ppm. Very common laboratory gas, also used as dry ice. Causes problems primarily by displacement of air. At 5% concentration, respiratory volume quadrupled. Heart rate and blood pressure increases reported at 7.6%. At 11%, unconsciousness typically occurs in 1 minute or less. No warning other than symptoms dizziness, headaches, shortness of breath, and weakness because it is colorless and odorless. 

Sensitization may last for many years or for life it usually lessens with time and most, but not all, people slowly become desensitized. A sensitized person must avoid further work with isocyanates and also asthmatic individuals should not work with isocyanates. Many employers who use isocyanates require their employees to be medically certified as free from respiratory problems and will systematically monitor their employees for maintenance of lung function through forced respiratory volume (FRV) monitoring. Further information is provided in the BRMA code of practice entitled Toxicity and Safe Handling of Diisocyanates and Ancilliary Chemicals a code of practice for polyurethane flexible foam manufacture. 

Vital capacity, respiratory volume, and expiratory volume decrease. Cough becomes weaker, decreasing clearance of secretions. 

The answer b 2 [Oiaf r 11 It C 4]. The approximate daily dcsage of hydrogen sulfide received by the pig is 40 mg/kg. The 24-hour respiratory volume is the product of the tidal volume, the respiratory rate, and amount of time ... 

The Respiratory Aetivity (RA) is a very important bio-medieal signal however, it is not eommonly monitored. Through the analysis of RA is possible to detect diverse respiratory pathologies, sueh as asthma, ehronie obstructive pulmonary disease (CORD) and sleep apnea-hypopnea syndrome. Nowadays, different methodologies exist, direct and indirect, to RA measurement. One of the methods is based on the Impedance Pneumography (IP), which is an indirect technique for continuous and dynamic measurement of respiratory volume [1]. The IP is a specialized type of impedance plethysmography (IPG). 

Grenvik A, Ballou S., McGinly E., et aL (1972). Impedance pneumography Comparison between chest impedance changes and respiratory volumes in 11 healthy volunteers. Chest, vol. 62, pp 439-443. 

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