Utilization of EMS Transport Among Patients with STEMI

Findings from the National Cardiovascular Data ACTION Registry–

Get With The Guidelines

Robin Mathews, Eric Peterson, Shuang Li, Matthew Roe, Stephen Wiviott, Jorge Saucedo, Elliott Antman, Tracy Wang

STEMI: Time is Muscle

ACC/AHA Guidelines for STEMI CareACC/AHA Guidelines for STEMI Care

• Early evaluation (e.g., pre-hospital ECG)• Pre-hospital stabilization• Expedited triage by receiving hospital

Antman, EM, 2004 JACC (45); 671-719Antman, EM, 2004 JACC (45); 671-719

NRMI data (1990s) showed only 50% EMS use

Canto, JG. 2002 Circulation (106): 3018-3023

Gaps in the DataGaps in the Data

What are contemporary patterns of EMS vs. What are contemporary patterns of EMS vs. self transport use among STEMI patients?self transport use among STEMI patients?

What are the barriers to EMS utilization?What are the barriers to EMS utilization?

Does EMS use improve timeliness of Does EMS use improve timeliness of subsequent treatment?subsequent treatment?

ACTION Registry®-GWTG™ STEMI population

Jan 01, 2007-SEP 30, 2009

Missing mode of transport Transfer- in patientsMissing home zip code information

Study Population 18,069 patients, 296 hospitals

Self Transport6,988 patients

38.7 %

EMS Transport11,081 patients

61.3 %

*Other variables in this model: dyslipidemia, diabetes mellitus, prior HF, HTN, atrial fibrillation/atrial flutter, prior MI, prior stroke, BMI, heart rate, dialysis, *Other variables in this model: dyslipidemia, diabetes mellitus, prior HF, HTN, atrial fibrillation/atrial flutter, prior MI, prior stroke, BMI, heart rate, dialysis, educational level, income level, race, time of presentation, rural vs. urban locationeducational level, income level, race, time of presentation, rural vs. urban location

Sociodemographic Factors Associated with EMS-TransportSociodemographic Factors Associated with EMS-Transport

Clinical Factors Associated with EMS-TransportClinical Factors Associated with EMS-Transport

EMS Transport Reduces Symptom Onset to Hospital EMS Transport Reduces Symptom Onset to Hospital Arrival Time Regardless of Distance Traveled Arrival Time Regardless of Distance Traveled

< 4 miles 4-10 miles >10 milesP-value <0.0001 <0.0001 <0.0001

0

100

200

300

400

500

600 EMSSelf

Tim

e (m

in)

Treatment Differences Between Treatment Differences Between EMS- and Self-TransportEMS- and Self-Transport

Adjusted OR (95%CI)Sx onset to arrival ≤ 120 min Time to ECG ≤ 10 min D2B ≤ 90 min 0.55 (0.50-0.60) 0.52 (0.46-0.59) 0.43 (0.37-0.50)

31 min 3 min13 min

P<0.001 for all

Limitations Limitations

Income and educational levels derived from home zip code and Income and educational levels derived from home zip code and census data.census data.

Distance traveled derived from home to hospital zip code and Distance traveled derived from home to hospital zip code and only approximates the travel distance for an individual patientonly approximates the travel distance for an individual patient

ACTION-GWTG did not capture symptom severityACTION-GWTG did not capture symptom severity

. .

ConclusionsConclusions

EMS continues to be underutilized among STEMI patients EMS continues to be underutilized among STEMI patients in contemporary practice in contemporary practice

Estimates of socioeconomic factors, such as household Estimates of socioeconomic factors, such as household income and insurance status, did not predict EMS income and insurance status, did not predict EMS utilization utilization

Patients who use EMS have significantly shorter delays to Patients who use EMS have significantly shorter delays to presentation and treatment, even among patients who live presentation and treatment, even among patients who live close to the hospital close to the hospital

ImplicationsImplications

EMS use, by reducing the delay from symptom EMS use, by reducing the delay from symptom onset to hospital arrival alone, is associated with a onset to hospital arrival alone, is associated with a >30 minute reduction in ischemic time >30 minute reduction in ischemic time

More work is needed to promote EMS use as More work is needed to promote EMS use as emphasized by Mission Lifeline’s ‘chain of survival’ emphasized by Mission Lifeline’s ‘chain of survival’

Community education efforts should be tailored to Community education efforts should be tailored to groups that underutilize EMS and integrated with groups that underutilize EMS and integrated with system-wide strategies to promote the timely use of system-wide strategies to promote the timely use of reperfusion reperfusion