Background: Although the incidence of acute respiratory distress syndrome has been studied, few researchers have prospectively assessed the search tool used to identify cases.
Methods: For 5 months, all patients admitted to a medical intensive care unit in a teaching hospital were evaluated daily to determine whether criteria for acute respiratory distress syndrome were met, and physicians' progress notes and discharge summaries for these prospectively identified patients were reviewed for mention of the syndrome. Discharge forms were reviewed for the codes (International Classification of Diseases, Ninth Revision) specific to acute respiratory distress syndrome (518.82 or 518.85).
Results: Of 314 patients admitted, 65 prospectively met the criteria for acute respiratory distress syndrome. Of these 65 patients, 31 had acute respiratory distress syndrome mentioned in their progress notes, and 4 of the 31 were subsequently assigned a code of 518.82 or 518.85. Patients with a physician's notation for acute respiratory distress syndrome in their charts had a higher mortality (22/31 [71%]) than did the patients with no such notation (10/34 [29%]). This difference could not be accounted for by differences in length of stay, mean age, score on Acute Physiology and Chronic Health Evaluation III, or number of days in the unit before meeting the criteria.
Conclusions: The incidence of acute respiratory distress syndrome is underestimated when based on either diagnostic coding or physicians' notes without testing of the accuracy of coding. Both physicians and medical record coding specialists may require training in use of terms related to acute respiratory distress syndrome.