Effect of prolonged exposure to elevated carbon monoxide and carbon dioxide levels on red blood cell parameters during submarine patrols.

Wilson, A. J., and K. E. Schaefer. 1979. Effect of prolonged exposure to elevated carbon monoxide and carbon dioxide levels on red blood cell parameters during submarine patrols. Undersea Biomed. Res. Sub. SuppL: S49-S56.—Twenty volunteers were chosen at random from the crew of a Polaris submarine to ascertain the effect of prolonged exposure to elevated levels of carbon monoxide and carbon dioxide on red blood ceil parameters during a routine patrol. Measurements were made of hemoglobin (Hb) concentrations, acmaiocEil (Hct; ieveis, and red blood ceB (RBO and reticuiocyte counts. The average CO concentrations during patrol remained below 20 ppm (range 15-20): the average CO. concentration was 0.9%. A base-line study was performed prior to patrol while the subjects were breathing atmospheric air. Three determinations were performed at different times during patrol. These studies revealed a statistically significant rise in Hbi Hct. and RBC counts during the first 32 days of patrol and a subsequent decline almost to base-line ievels on the 52nd d2y of patrol. Chronic exposure to low levels of carbon monoxide (caused by smoking) is known to produce a rise in Hb, Hct. and red cells, to compensate for the anoxic stress induced by higher carboxyhemoglobin levels (HbCO). Inhalation of CO2 in higher concentrations (5-89c CCO causes an increase in ventilation and higher Oj tensions, which are known to inhibit the erythropoietic response caused by acute or chronic hypoxia. However, the CX>2 concentration of 0.9% found in submarines is apparently too low to compensate for the slight anoxic stress produced by increased ieveis of CO. Both smokers and non-smokers showed this response: however, only smokers exhibited a rise in reticulocyie counts.