Direct admission to the coronary care unit by the ambulance service for patients with suspected myocardial infarction

Abstract

Background: Direct access to the coronary care unit (CCU) for general practitioner (GP) referred cases of suspected acute myocardial infarction (AMI) (fast track admission) substantially reduces the time to thrombolysis. Until now, this policy has been confined to GP referrals.

Objectives: To determine the time taken to admission to CCU under the fast track policy (ambulance referrals and GP referrals) and the time taken to start administration of thrombolytics (ambulance referrals, GP referrals, and accident and emergency referrals).

Methods: Fast track admission policy was extended to include referrals from ambulance personnel who respond to emergency service calls. Ambulance personnel referred cases were also examined to see if they were referred appropriately to the CCU.

Results: 100 ambulance personnel referrals and 260 GP referrals to CCU with chest pain were studied. Forty accident and emergency referrals who had AMI requiring thrombolysis were also studied. In the ambulance referred group the time to admission from phone call was a median of 10 minutes (range 2 to 45), a saving of 30 minutes compared with GP referrals (median 40 minutes, range 2 to 217). The median diagnostic electrocardiogram (ECG) to thrombolysis time was longer in the accident and emergency referrals with AMI than either ambulance referrals or GP referrals admitted under the fast track policy. Diagnostic ECG to thrombolysis time: accident and emergency 50 minutes (range 15 to 385); ambulance referrals median 33 minutes (range 6 to 69); GP referrals median 29.5 minutes (range 5 to 110 minutes); (p = 0.056 accident and emergency compared with ambulance referrals, p < 0.002 accident and emergency compared with GP referrals). Of 100 ambulance referrals 52 patients exhibited symptoms suggestive of ischaemic heart disease (confirmed AMI, unstable angina, and angina) and a further 18 patients were required to stay in CCU for other cardiac problems. Thus a total of 70 (70%) were considered appropriate compared with 155 of 260 (55.8%) GP referred cases.

Conclusions: Extending the fast track admission policy to ambulance personnel reduces delay to admission for patients with suspected MI without adversely affecting the appropriateness of admissions.

Figure 1

Time taken from phone call to admission to coronary care (CCU) in suspected acute myocardial infarction (AMI) and those patients requiring thrombolytic therapy once admitted. Ambulance referrals arrive earlier to CCU than GP referrals (median values; error bars, standard deviations).