Quote
We searched for diagnoses of ICD-9 code 995.0 (anaphylactic shock), E948.0 through E948.9 (adverse reaction from bacterial vaccines), and E949.0 through E949.9 (adverse reaction from other vaccines and biological substances). We restricted our review to diagnoses occurring on days 0 to 2 after vaccination (day 0 defined as the same day as vaccination) for ICD-9 code 995.0 and day 0 for ICD-9 codes E948.0 to E948.9 and E949.0 to E949.9. Because some cases of anaphylaxis may receive other related allergy diagnoses, at 1 of the study sites, we also performed a chart review of all day 0 diagnoses of 708.0 (allergic urticaria), 708.9 (urticaria unspecified), 995.1 (angioneurotic edema), 995.3 (allergy unspecified), 695.1 (erythema multiforme), and 995.2 (unspecified adverse effect of drug, medicinal and biological substance).