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Benzodiazepine Overdose v2 Parsed

Query purpose: 

To assist state, local, tribal, territorial, and federal public health practitioners in monitoring emergency department (ED) visits for suspected nonfatal benzodiazepine-involved overdoses using syndromic surveillance data.

Definition description: 

The benzodiazepine overdose syndrome definition was designed to identify emergency department (ED) visits for suspected nonfatal benzodiazepine-involved overdoses of unintentional or undetermined intent. The query uses two fields from ED visit records to identify encounters that meet the definition criteria:

  1. the chief complaint free text field is queried for terms indicating an overdose/poisoning and benzodiazepine involvement and for relevant exclusion terms (e.g., terms indicating benzodiazepine administration by medical personnel or withdrawal without acute intoxication, etc., which would exclude ED visit records from this syndrome definition), and
  2. the discharge diagnosis parsed coded field is queried for International Classification of Diseases, 9th Revision (ICD-9-CM),1 10th Revision (ICD-10-CM),2 and Systematized Nomenclature of Medicine – Clinical Terms (SNOMED-CT)3 diagnosis codes indicating acute benzodiazepine poisoning of unintentional or undetermined intent.

Within ESSENCE, the syndrome query is applied to the Chief Complaint Discharge Diagnosis (CCDD) Parsed field, which combines these two fields of interest.

How it was developed: 

This revision was developed to adapt the CDC Benzodiazepine Overdose v1 definition syntax to query the newly developed CCDD Parsed field which removes extraneous test from the discharge diagnosis portion of the CCDD.

CDC scientists first started developing the definition using lessons learned from jurisdictions funded by CDC’s Overdose Data to Action (OD2A) and Enhanced State Opioid Overdose Surveillance (ESOOS) Programs. First, ICD-9-CM, ICD-10-CM, and SNOMED-CT diagnosis codes indicating acute benzodiazepine misuse/dependence and/or benzodiazepine poisoning were identified; this was followed by benzodiazepine-specific terms and overdose terms in the chief complaint field. Lastly, exclusion terms were identified (e.g., terms indicating benzodiazepine administration by medical personnel, withdrawal without acute intoxication, etc.) to avoid incorrectly capturing encounters that were not for a benzodiazepine-involved overdose.

How it works:

The CCDD Parsed field is used to query both the diagnosis codes and chief complaint free text with exclusions (as necessary) to develop the syndrome definition.

  • Automatic inclusion:
    • If a diagnosis code indicating a benzodiazepine poisoning is present, the ED visit is automatically included in the syndrome.
  • Conditional inclusion:
    • If the ED visit does not include a diagnosis code for benzodiazepine poisoning, then the visit is not automatically included.
    • The visit is captured only if it includes two components:
      • 1) chief complaint text indicating an overdose or poisoning AND
      • 2) chief complaint text indicating benzodiazepine involvement OR a SNOMED-CT code for benzodiazepine misuse or dependence.
    • The list of exclusions is applied to the chief complaint text only when a discharge diagnosis code is not present for benzodiazepine poisoning, or for any of the conditional inclusions mentioned above.

For consideration:

This definition is subject to both misclassification, overreporting, and underreporting for several reasons, including limited point-of-care confirmatory testing to identify the drug(s) involved in the overdose and reliance on self-report, bystander reports, and/or clinical presentations to determine the drug(s) involved in an overdose. The codes provided in the discharge diagnosis field from the ED visit record do not necessarily represent the final diagnosis of a patient and should be considered preliminary. Additionally, some hospitals may enter all diagnosis codes from a patient’s entire medical history, including codes for previous benzodiazepine-involved overdose visits; the definition may incorrectly capture such encounters that were not for a true benzodiazepine-involved overdose and thus result in overreporting. Benzodiazepines may be administered by medical personnel in the ED setting or by emergency medical services technicians as a sedative en route to the ED, and this information could have been added into the chief complaint field. We attempted to identify all possible exclusion terms to avoid capturing encounters that describe benzodiazepines administered in a medical setting and not a benzodiazepine-involved overdose; however, it is possible that some of these encounters were erroneously captured, leading to overreporting. The team attempted to identify all appropriate inclusion and exclusion terms to capture any suspected nonfatal benzodiazepine-involved overdoses while avoiding capturing encounters that were not for an acute benzodiazepine-involved overdose or poisoning, but it is possible that some of these encounters were erroneously captured, leading to overreporting.

Syndrome Definition

(,^;9694;^,OR,^;T424X[14]A;^,OR,^;296128004;^,OR,^;216530001;^,OR,^;296129007;^,OR,^;296053004;^,OR,^;712742003;^,OR,^;81914009;^,),OR,(,(,(,^poison^,OR,^verdo[se][es]^,OR,^over dose^,OR,^overose^,OR,^nodding^,OR,!nod!,OR,^snort^,OR,^in[gj]est^,OR,^intoxic^,OR,^unresponsiv^,OR,^loss of consciousness^,OR,^syncop^,OR,^shortness of breath^,OR,^short of breath^,OR,^altered mental status^,),AND,( ,!prosom!,OR,!niravam!,OR,!tranxene!,OR,!oxazepam!,OR,!byfavo!,OR,!flurazepam!,OR,![zx]ans!,OR,![zx]anny!,OR,![zx]annies!,OR,!dalmane!,OR,!downers!,OR,![zx]an bar!,OR,![zx]anbar!,OR,!z bar!,OR,!k pin!,OR,!phennies!,OR,!B[ZD][ZD]!,OR,!BZ!,OR,^roofies^,OR,^benzos^,OR,^benzodiazepine^,OR,^benezos^,OR,^clorazepate^,OR,^diaz[aei]pa[mn]^,OR,^clonazepam^,OR,^midazolam^,OR,^alprazolam^,OR,^temaz[aei]pam^,OR,^alprazolam^,OR,^ xan^,OR,xan^,OR,Xan^,OR,^[zx]an[oae]x^,OR,^helex^,OR,^trankimazin^,OR,!onax!,OR,!alprox!,OR,!misar!,OR,!restyl!,OR,!tafil!,OR,!frontin!,OR,!librium!,OR,^solanax^,OR,^[ck]lon[ae]z[ea]p[eoa]m^,OR,^[ck]lon[iao]pin^,OR,^valium^,OR,^valum^,OR,^iktorivil^,OR,^paxam^,OR,^riv[oa]tril^,OR,^antenex^,OR,^apaurin^,OR,^apzepam^,OR,^apozepam^,OR,^hexalid^,OR,^normabel^,OR,!pax!,OR,!ronal!,OR,!vival!,OR,^stesolid^,OR,^stedon^,OR,^valaxona^,OR,^hipnosedon^,OR,^vulbegal^,or^fluscand^,OR,^flunipam^,OR,^rohydorm^,OR,^hypnodorm^,OR,^loraz^,or!ativan!,OR,^zolam^,OR,^bromazepam^,OR,^diazepoxide^,OR,^serax^,OR,^temazepa[nm]^,OR,^restor[aie]l^,OR,^halcion^,OR,^;428406005;^,OR,^;231473004;^,),ANDNOT,(,^ plan to overdose on benzo^,OR,Plan to overdose on benzo^,OR,!plan to overdose on [zx]an[oae]x!,OR,!plan to overdose on Ativan!,OR,!plan to overdose on valium!,OR,^ xanthogranulomatous ^,OR,!acetazolamide!,OR,^placed on ativan^,OR,^placed on valium^,OR,^placed on [zx]an[oae]x^,OR,^ran out of ativan^,OR,^ran out of valium^,OR,^ran out of [zx]an[oae]x^,OR,^ativan prn^,OR,^valium prn^,OR,^[zx]an[oae]x prn^,OR,^treated by ativan^,OR,^treated with ativan^,OR,^given ativan^,OR,^gave ativan^,OR,^ativan given^,OR,^treated by valium^,OR,^treated with valium^,OR,^treated by [zx]an[oae]x^,OR,^treated with [zx]an[oae]x^,OR,^given valium^,OR,^gave valium^,OR,^valium given^,OR,^[zx]an[oae]x given^,OR,^given [zx]an[oae]x^,OR,^gave [zx]an[oae]x ^,OR,^rec[ie][ei]ved ativan^,OR,^does not have any ativan left^,OR,^does not have any valium left^,OR,^does not have any [zx]an[oae]x left^,OR,^stopped using valium^,OR,^stopped using [zx]an[oae]x^,OR,^stopped using ativan^,OR,^out of valium^,OR,^out of [zx]an[oae]x^,OR,^out of ativan^,OR,^benzonatate^,OR,^no loss of consciousness^,OR,^denie[sd] loss of consciousness^,OR,^negative loss of consciousness^,OR,^denies any loss of consciousness^,OR,^denies drug^,OR,^deny drug^,OR,^denied drug^,OR,^denying drug^,OR,^denies any drug^,OR,^ with dra^,OR,^withdra^,OR,^detoxification^,OR,^detos^,OR,^detoz^,OR,^dtox^,),),)

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