PURPOSE:To investigate the diagnostic efficacy of a new computer-aided pH-logPaCO2 diagram in the diagnosis of acid-base disorders. The innovative theory of the “multiple overlapping areas”, which estimates not only the most possible diagnosis but also all the alternative diagnoses that may correspond to a specific acid-base disorder according to their relevant probability, has been incorporated with the aid of an appropriate software to the new diagram.
METHODS:3.122 arterial blood gas samples were drawn from 114 ICU patients and interpreted with: 1) The new acid-base diagram and the corresponded software, 2) the “Grogono” diagram, 3) The “Siggaard-Andersen” chart, 4) The “Oxygen Status Algorithm Software”, and 5) Two physicians with more than 10 years of experience in ICU, considered experts in acid-base disorders. The statistically significant difference between the diagnostic agreements of the above methods was tested with the K-statistics.
RESULTS:1) The new acid-base diagram presents the greatest diagnostic agreement with all the other methods, especially in the central and the radial “overlapping areas” (>80%). 2) In the “non-overlapping areas” the diagnostic agreement of the new diagram with all the other methods is significantly less than in the “overlapping areas” because of the inability of the software to provide more than one diagnosis, and 3) The fact that the two experts disagree in the 1/3 of the blood samples indicates that despite the technological evolution in the laboratory testing of the arterial blood gases, there is lack of a referral technique among the experts for the diagnosis of the acid-base disorders.
CONCLUSION:The extremely high diagnostic agreement of the new diagram with all the other methods, especially in the “overlapping areas”, is attributed to the ability of the software to provide all the alternative diagnoses that may correspond to the specific acid-base disorder.
CLINICAL IMPLICATIONS:The proposed diagram in conjunction with the accompanying software can be a useful, fast, safe and accurate diagnostic technique for the diagnosis of acid-base disorders.
DISCLOSURE:Nikolaos Theakos, No Financial Disclosure Information; No Product/Research Disclosure Information