[Comparison between the poisoning severity score and specific grading scales used at the Department of Clinical Toxicology in Krakow]. / Porównanie skali Poisoning Severity Score i specyficznych skal ciezkosci zatrucia uzywanych w Klinice Toksykologii Collegium Medicum UJ.

ABSTRACT

The aim of the present study has been to assess the concordance in severity grading when using the Poisoning Severity Score (PSS), proposed by IPCS/EC/EAPCCT vs. some specific grading scales. Cases of acute poisoning admitted to the Department of Clinical Toxicology in Kraków during months January, March, May, July, August and October 1998 (n = 820) were evaluated. Severity grading was performed in all cases using both the PSS and special grading scales developed by the poisons centre in Kraków. The PSS is assessing severity on the basis of observed clinical signs and symptoms (at their maximum), but does not take into account potential risks or plasma/serum concentrations. The Kraków scales include both clinical symptoms on admission and results of toxicological analyses. Ethanol (39.4%), drugs (36.2%) and carbon monoxide (7.9%) were the most commonly involved toxic agents. Overall concordance between the PSS and the Kraków scales was at hand in 596 cases (72.7%). The lack of concordance was most evident for ethanol and carbon monoxide cases--the PSS generally giving a lower grade. The discordance was less pronounced for grade 3 (life-threatening) poisonings. Significant number of ethanol poisoning in Kraków centre require medicolegal certification thus ethanol concentration (blood or expired air) is considered while evaluating the poisoning severity. Moreover majority (more than 70%) of acutely ethanol poisoned patients treated at the Department are chronic alcoholics so clinical evidence of intoxication may be minimal at blood ethanol levels higher than 3.0 g/L. For ethanol intoxication the blood ethanol concentration was considered in the Kraków scale but not in the PSS, and when the blood concentrations were disregarded and clinical symptoms only were evaluated the concordance improved between the different systems from 72.7% to 92.3%. Thereby also the overall concordance in the study increased to 82.9%. The less satisfying concordance for carbon monoxide cases was mainly caused by discrepancies in the evaluation of neurological symptoms. Also the blood lactate concentration, COHb level, duration of exposure and patient's age are considered in the Kraków scale but not in PSS. The PSS is intended as a general scheme for grading severity of acute poisoning. In this study an acceptable concordance between the PSS and some locally developed grading scales was at hand in the majority of cases, but it seems that for specific poisons, like carbon monoxide, some modifications and additional criteria may be justified. Further studies to test the reliability of the PSS are encouraged.