Carbon dioxide narcosis

Miller, A. L. Carbon dioxide narcosis. In D. W. McCandless (ed.) Cerebral Energy Metabolism and Metabolic Encephalopathy. New York Plenum Press, 1985, pp. 143-162. 

Morphine depresses respiration, principally by reducing sensitivity of the respiratory centre to increases in blood PaCOj. With therapeutic doses there is a reduced minute volume first due to diminished rate and then tidal volume. With higher doses carbon dioxide narcosis may develop. In overdose the patient may present with a respiratory rate as low as 2/min. 

Long-term oxygen therapy has been shown to improve the client s quality of life and survival. The oxygen must be kept between 1 and 3 L/min to prevent respiratory failure, which occurs when the oxygen level is increased and the client s hypoxic drive is no longer active. Carbon dioxide narcosis occurs in clients with COPD and eliminates that stimulus for breathing. 

After 6, 12 and 26 weeks, 5 rats in each group were killed after 16 hours fasting by carbon dioxide narcosis. Blood was withdrawn by cardiac puncture (17). 

When simple substances, even those that are intimately associated with living processes, are tested upon organisms, the results may be highly variable depending on the genetics of the organism tested. Thus, there are strains of Drosophila which are sensitive and resistant, respectively, to carbon dioxide. Some can stand hours of contact with pure carbon dioxide without permanent injury, while others either do not recover from the narcosis or, if they do, their movements... 

Narcosis due lo CO is characterized by mental disturbances which may range from confusion, mania, or drowsiness to deep coma, headache, sweating, muscle twitching, increased intracranial pressure, pounding pulse, low blood pressure, hypothermia, and sometimes papilloedcina. The basic mechanisms by which carbon dioxide induces narcosis is probably through interference with the intracellular enzyme systems, which are all sensitive to pll changes. 

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