Custom alert analysis
A variety of drugs triggered a risk score calculation. Table A.2 in the
supplementary appendix displays the top drugs triggering risk score
calculation stratified by route, risk for TdP based on CredibleMeds
list, percentage of all alerts generated, the action that triggered the
score calculation, and QTc prolongation associated with each drug. As
mentioned earlier, the risk score calculation was generated upon
signature or verification of a QTc-prolonging medication from any of the
CredibleMeds lists 1, 2 or 3. Intravenous (IV) ondansetron, furosemide
and diphenhydramine contributed to 13%, 11%, and 9% of the risk score
calculations respectively, and ultimately, custom alerts. Based on
follow up ECG review, QTc prolongation was most associated with IV
haloperidol (88% of alerts triggered resulted in QTc prolongation),
followed by oral methadone (71%), IV metoclopramide (38%), IV
promethazine (31%), oral tramadol (25%), and IV ondansetron (25%).
A total of 172 out of 521 (33%) triggering medications were ordered to
be administered on an as needed basis (PRN). The top PRN medications
including percentage of alerts generated and QTc prolongation are shown
in table A.3 in the supplementary appendix. However, data on the number
of doses administered was not collected as this was not within the scope
and timeline of our project.