Evaluation of the validity of the Done nomogram in the management of acute salicylate intoxication

Abstract

To evaluate the validity of the Done nomogram in the management of acute adult salicylate intoxications, a retrospective review of cases at our institution was performed. The degree of severity (ie, asymptomatic, mild, moderate, or severe) as determined by plotting the serum concentration and time on the nomogram for 55 acute salicylate intoxications was compared with the degree of severity decided on by three experienced emergency physicians who based their decision on the clinical presentation of the cases and the original criteria devised by Done for each category of severity. Discordant classifications between the nomogram and the physicians provided a basis on which a predictive index for the nomogram and various subsets of cases could be determined. The calculated predictive index for the nomogram was 0.42, with the highest predictive index of 0.79 in the mild salicylate category. The nomogram tends to overpredict the severity of intoxication in the moderate and severe categories. There was no significant difference between predictive indexes of mixed versus nonmixed or enteric-coated acetylsalicylic acid versus plain acetylsalicylic acid cases, although the nomogram had a higher predictive index when used for concentrations drawn six to 12 hours after ingestion (P less than .01, Fisher's exact test). Decisions on management of an acute salicylate overdose should be based on clinical presentation and good judgment as well as the serum salicylate concentration in relation to the time of ingestion.