Respiratory volume, increased

Phosgene poisoning may cause respiratory and cardiovascular failure which results in low plasma volume, increased hemoglobin concentration, low blood pressure, and an accumulation of fluid in the lungs. There is no antidote for phosgene, and treatment consists of support of respiratory and cardiovascular functions. 

More severe respiratory effects (increased lung weight, increase in the accumulation of alveolar macrophages, increase in the density of type II cell volumes) were observed in rabbits exposed by inhalation to both nickel and trivalent chromium than in rabbits exposed to nickel only (Johansson et al. 1988b). 

Desflurane does not have a marked bronchodilator effect and in cigarette smokers it is associated with significant bronchoconstriction. In clinical practice, both humidification of inspired gases and opioids are thought to reduce airway irritability but even at moderate concentrations (2 MAC), desflurane is more likely to cause coughing than sevoflurane. In common with other volatile agents, desflurane causes dose-related respiratory depression. Tidal volume is reduced and respiratory rate increases, initially. As inspired concentrations of desflurane increase, the trend is to hypoventilation and hypercardia and apnoea is to be expected at concentrations of 1.5 MAC or greater. 

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... 

Respiratory effects. Isoflurane causes respiratory depression the respiratory rate increases, tidal volume decreases, and the minute volume is reduced. The ventilatory response to carbon dioxide is diminished. Although it irritates the upper airway it is a bronchodilator. 

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

Amphetamine stirrmlates the respiratory center, increasing the rate and depth of respiration. In normal individuals, usual doses of the drug do not appreciably increase respiratory rate or minute volume. Nevertheless, when respiration is depressed by centrally acting drugs, amphetamine may stimulate respiration. 

ACUTE HEALTH RISKS irritation of skin, eyes, and respiratory system headache weakness dizziness drowsiness anoxia microhematuria urine volume increase formation of methemoglobinemia possible cyanosis destructive to tissues of mucous membranes difficulty in breathing psychic disturbances irritation of kidneys and bladder skin bums dermatitis. 

Poulsson in 1920 (140) reviewed the literature concerning the pharmacodynamics of cocaine and noted that there was little information relative to the action of this alkaloid on respiration. At the beginning of intoxication by cocaine, the respiratory center is stimulated and the respiratory rate and volume increase. Strong doses further increase the respiratory rate but the respiration becomes superficial and is intermpted by pauses, i.e., Cheyne-Stokes respiration. In the intoxicated man a bradycardia is noted. 

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). 

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. 

Dill seed oil has been reported to have spasmolytic effects on smooth muscles, especially those of the GIT. A 5% emulsion in physiological saline administered intravenously to cats (5-lOmg/kg) increased respiratory volume and lowered blood pressure, while guinea pigs receiving a higher dose (35 mg/kg) via i.p. injection went into anaphylactic shock. ... 

When administered to rabbits orally or per intramuscular injection, the oil caused arterial hypotension accompanied by increased rhjdh-mic contraction of the heart, and in higher dosage also increased respiratory frequency. When given intravenously to cats as a 5% emulsion in saline solution, thyme oil also increased respiratory volume and lowered blood pressure. ... 

The classical Warburg method of manometric indirect calorimetry (see e.g. [41 ]) determined the oxygen consumption rate by a reduction of volume and the carbon dioxide production by a volume increase in the gaseous environment of an organism under research. The ratio of carbon dioxide production and oxygen consumption, the so-called respiratory quotient RQ, rendered information about the substrate(s) used in this specific metabolism. Table 2 presents the RQ values for various pure or mixed substrates and the expected heat production or gas exchanges. 

Isoflurane is a respiratory depressant (71). At concentrations which are associated with surgical levels of anesthesia, there is Htde or no depression of myocardial function. In experimental animals, isoflurane is the safest of the oral clinical agents (72). Cardiac output is maintained despite a decrease in stroke volume. This is usually because of an increase in heart rate. The decrease in blood pressure can be used to produce "deHberate hypotension" necessary for some intracranial procedures (73). This agent produces less sensitization of the human heart to epinephrine relative to the other inhaled anesthetics. Isoflurane potentiates the action of neuromuscular blockers and when used alone can produce sufficient muscle relaxation (74). Of all the inhaled agents currently in use, isoflurane is metabolized to the least extent (75). Unlike halothane, isoflurane does not appear to produce Hver injury and unlike methoxyflurane, isoflurane is not associated with renal toxicity. 

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