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Prehospital Thrombolysis: A Manual from Berlin
05:52

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Published on: November 26, 2013

Delay in thrombolysis administration: causes of extended door-to-drug times and the asymptote effect

M J Sagarin1, C P Cannon, M S Cermignani

  • 1Harvard Affiliated Emergency Medicine Residency Program, Harvard Medical School, Boston, Massachusetts, USA. msagarin@bics.bwh.harvard.edu

The Journal of Emergency Medicine
|August 8, 1998
PubMed

Insights

Delays in emergency department treatment for acute myocardial infarction (AMI) are common, often due to diagnostic challenges or contraindications. Many AMI cases lack clear reasons for delayed thrombolytic therapy.

Area of Science:

  • Cardiology
  • Emergency Medicine
  • Health Services Research

Background:

  • Thrombolytic therapy is a critical treatment for acute myocardial infarction (AMI).
  • Optimizing door-to-drug times in the emergency department (ED) is a key quality metric for AMI care.
  • Understanding reasons for treatment delays is essential for improving patient outcomes.

Purpose of the Study:

  • To retrospectively analyze causes of delayed thrombolytic therapy in patients with acute myocardial infarction (AMI).
  • To identify factors contributing to prolonged door-to-drug times in the emergency department (ED).
  • To evaluate the impact of patient populations with atypical presentations or contraindications on median treatment time analyses.

Main Methods:

  • Retrospective analysis of medical records and critical pathway data for AMI patients receiving thrombolytic therapy.
  • Determination of door-to-drug times for all analyzed patients.
  • Detailed examination of records for patients with door-to-drug times exceeding the median to identify causes of delay.

Main Results:

  • Identified causes for treatment delays included: initial electrocardiogram acquisition (24%), atypical presentations (11%), ruling out contraindications (11%), diagnosis confirmation (14%), and miscellaneous factors (8%).
  • A significant proportion of patients (32%) had no identifiable reason for delay.
  • Certain AMI patient subgroups, such as those with atypical presentations or requiring evaluation for contraindications, may not fit standard treatment pathways.

Conclusions:

  • Treatment delays in AMI thrombolysis are multifactorial, involving diagnostic and logistical challenges.
  • A substantial percentage of delays lack clear explanations, necessitating further investigation.
  • The heterogeneity of AMI presentations and contraindications can complicate quality improvement initiatives based on median door-to-drug times.

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