prehospital stemi care
TRANSCRIPT
Prehospital STEMI CarePrehospital STEMI Care
BREMSS EMS ConferenceBREMSS EMS ConferenceJanuary 14-16, 2010January 14-16, 2010
DefinitionDefinition
ST-elevation Myocardial ST-elevation Myocardial InfarctionInfarction
ST SegmentST Segment
MyocardiumMyocardium
InfarctionInfarction
Irreversible tissue injury due to Irreversible tissue injury due to ischemia, or insufficient blood flow.ischemia, or insufficient blood flow.
Infarct
CausesCauses
Coronary Artery Coronary Artery Disease Disease (CAD)(CAD)
EmbolicEmbolic Coronary VasospasmCoronary Vasospasm Aortic DissectionAortic Dissection OtherOther
PathophysiologyPathophysiology
Typically results from Typically results from thrombosis (clot formation) of thrombosis (clot formation) of a coronary arterya coronary artery
Usually due to spontaneous Usually due to spontaneous rupture of a vulnerable rupture of a vulnerable atherosclerotic plaque.atherosclerotic plaque.
Coronary Thrombosis
Non-occlusive(non-STEMI)
Occlusive(STEMI)
PortraiPortrait of a t of a KillerKiller
How Does MI Kill?
VT/VF Cardiogenic Shock VSD, Cardiac Rupture Stroke CHF
Diagnosis: EKG
Characteristic changes Often changes on a minute-by
minute basis Initial tracing may not be
diagnostic Typical progression as time
passes
Firehats
Tombstones
Normal EKG
MIs Categorized by Location
Anterior Septal Lateral Inferior Combinations
Standard Lead Placement
Septal Anterior Lateral
Inferior Rhythm Strip
Anterior STEMI
Anteroseptal Infarct
Inferior MI
STEMI Mimics
Pericarditis Early Repolarization
Treatment: Reperfusion “Clot-buster”
Medications– AKA
thrombolytics, fibrinolytics
Angioplasty– AKA PTCA, PCI
Treatment Goals
Thrombolytics – 30 minutes from arrival to ED (Door to Needle)
PCI – 90 minutes from arrival(Door to Balloon; D2B)
NB: Non-EMS patients
Why PCI?
Lytics are– Widely available– Readily delivered– Cheaper– No radiation– No contrast (dye) exposure
But . . .
PCI results in– Less mortality– Less reinfarction / reocclusion– Less intracranial bleeding– Less recurrent ischemia
Also, 20% of patients are not eligible for thrombolysis.
Contraindications and Cautions for Fibrinolysis in ST ElevationMyocardial Infarction* Absolute contraindications
– Any prior ICH– Known structural cerebral vascular lesion (e.g., arteriovenous malformation)– Known malignant intracranial neoplasm (primary or metastatic)– Ischemic stroke within 3 months EXCEPT acute ischemic stroke within 3 hours– Suspected aortic dissection– Active bleeding or bleeding diathesis (excluding menses)– Significant closed-head or facial trauma within 3 months
Relative contraindications– History of chronic, severe, poorly controlled hypertension– Severe uncontrolled hypertension on presentation (SBP > 180 mm Hg or DBP > 110
mmHg)†– History of prior ischemic stroke greater than 3 months, dementia, or known
intracranial pathology not covered in contraindications– Traumatic or prolonged (greater than 10 minutes) CPR or major surgery (less than 3
weeks)– Recent (within 2-4 weeks) internal bleeding– Noncompressible vascular punctures– For streptokinase/ anistreplase: prior exposure (more than 5 days ago) or prior
allergic reaction to these agents– Pregnancy– Active peptic ulcer– Current use of anticoagulants: the higher the INR, the higher the risk of bleeding
ICH = intracranial hemorrhage; SBP = systolic blood pressure; DBP = diastolic blood pressure;CPR = cardiopulmonary resuscitation; INR = international normalized ratio; MI =myocardial infarction.
*Viewed as advisory for clinical decision making and may not be all-inclusive or definitive.†Could be an absolute contraindication in low-risk patients with MI (see Section 6.3.1.6.3.2).
2004 STEMI Guidelines
Why Are We Here?
When PCI capability is available, the best outcomes are achieved by offering this strategy 24 hours per day, 7 days per week. The systems goal should be a first medical contact–to-balloon time within 90 minutes.
Circulation, 1/2008: Focused STEMI Update
This Is A Tall Order
Note “medical contact” is defined as “time of EMS arrival on scene” after the patient calls EMS/9-1-1 or “time of arrival at the emergency department door” (whether PCI-capable or non–PCI-capable hospital) when the patient transports himself/herself to the hospital.
BREMSS Region
STEMI System Hospitals
Birmingham VAMC Brookwood Princeton BMC Shelby BMC St. Vincent’s St. Vincent’s East Trinity UAB
Receiving
Chilton Medical Center Cooper Green Mercy Lakeland Community
Hospital St. Vincent’s Blount St. Vincent’s St. Clair UAB Highlands UAB West Walker BMC
Referring
STEMI Chain of Reperfusion
Symptom onset Decision to seek medical attention Access medical system Arrive ED EKG Decision Notify cath lab Cath lab arrival Patient to cath lab PCI
Total Reperfusion Time
Scene Time 8 10
Transport Time 12 12
Door to EKG 5 -14
EKG to Decision 5 5
Decision to Cath Lab 30 30
Cath Lab/PCI Time 15 15
Total 75 58
Fundamental Equation
=
Minutes = Muscle
Obviously, even more time can be saved by diverting from a non-PCI-capable hospital to a PCI center.
Uncertain Risks
ConclusionConclusion