Ischemia modified albumin levels in carbon monoxide poisoning and their correlation with histopathological damage

Aim: To determine the diagnostic value of blood ischemia modified albumin (IMA) levels in experimentally induced CO poisoning and to analyze the correlation with poisoning severity and mortality.Materials and Methods: Thirty-six female rats were randomly assigned to one of 6 groups; Groups I (control group), II (low dose CO poisoning) and III (high dose CO poisoning) for the investigation of the diagnostic value of IMA, and Groups IV (control group), V (low dose CO poisoning) and VI (high dose CO poisoning) for the analysis of the correlation between IMA levels and mortality. The control groups (I and IV) were kept at room temperature for 30 min, while Groups II and V were exposed to 3 l/min of 3000 ppm CO gas and Groups III and VI to 3 l/min of 5000 ppm CO gas. Blood samples were taken for COHb, IMA and MDA measurement from Group I, II and III rats in which the diagnostic value of IMA was to be investigated while brain, heart, lung, liver and kidney tissues were removed and analyzed using MDA measurement and histopathological scoring. Blood specimens for IMA levels were taken from group IV, V and VI rats for the analysis of IMA in terms of mortality at the end of the experiment, and mortality was monitored for a month with no additional procedure being performed.Results: No information could be obtained regarding the value of IMA levels in terms of mortality since none was determined in rats in Groups IV, V and VI, monitored in terms of mortality, over a period of 1 month.Of those groups in which the diagnostic value of IMA was investigated, IMA levels were significantly higher (1.57±0.08 ABSU) in the 3000 ppm low CO poisoning group (Group II) and 5000 ppm high CO exposure group (Group III) (1.53±0.11 ABSU) compared to the non-poisoning group (Group I) (1.35±0.2 ABSU) (p<0.05). A significant positive correlation was observed between COHb and IMA levels (r=0.508, p=0.03). Significantly higher histopathological damage in all organs was determined in both the 3000 ppm low CO group and the 5000 ppm high CO group compared to the control group (p<0.05). When the correlation between histopathological damage and biochemical parameters was investigated we observed a strong positive correlation between COHb levels and degree of damage in all organs (p<0.005), though IMA and MDA levels reflected no similar relationship.Conclusion: There is a global hypoxic process in the whole body in CO poisoning, not just in the heart, brain and kidney. Blood IMA levels in CO poisoning rise in correlation with those of COHb, the current diagnostic parameter. These findings reflect the diagnostic use potential of IMA levels in CO poisoning. Although our study determined that COHb levels histopathologically reflect poisoning severity better than other parameters, this important subject needs to be clarified through further research.Key words: Carbon monoxide poisoning, ischemia modified albumin