PURPOSE:Acute myocardial infarction kills about 120 000 people every year in the UK. Half of these deaths occur before patients reach hospital. Pre-hospital thrombolysis reduces mortality from ST-elevation Myocardial Infarction (STEMI) by 1.3%. Three main factors affect the efficacy of pre-hospital thrombolysis: i) time taken between patient calling for help and patient receiving treatment i.e. call-to-needle time (UK national target is < 60 minutes), ii) weight-adjusted thrombolytic dose (tenecteplase) and iii) using enoxaparin prior to tenecteplase. This audit compares thrombolytic treatment delivered by UK North West Ambulance Services against recommendations from the European Society of Cardiology. Outcomes at 30 days are also examined.
METHODS:Retrospective audit of patients who were thrombolysed by North West Ambulance Services from October 2006 to October 2007. 34 patients were obtained. Information was gathered from ambulance sheets and hospital notes. Patients with angina and non-STEMI were excluded.
RESULTS:All patients received pre-hospital thrombolysis within the national target time.Only half the patients were given the correct thrombolytic dose for their weight; 24% did not have their weight recorded in the notes. Two patients did not receive enoxaparin. At 30 days, five patients were admitted with re-infarction or unstable angina. Furthermore, two patients were thrombolysed unnecessarily since their final diagnosis at discharge was not of myocardial infarction.
CONCLUSION:The North West Ambulance Services are meeting the target for call-to-needle times. However, there seems to be poor compliance in terms of dose calculation for patients’ weights. Finally, decision made by paramedics to thrombolyse was not always correct.
CLINICAL IMPLICATIONS:More training should be provided to paramedics in terms of i) Thrombolytic dose conversion ii)Use of enoxaparin as part of a systematic routine and iii)ECG interpretation.Paramedics should be encouraged to send ECGs by telemetry, especially in case of diagnostic doubt. Adding a weight-dose conversion table and a checklist to ambulance sheets would be useful.
DISCLOSURE:Gemina Doolub, No Financial Disclosure Information; No Product/Research Disclosure Information