Chapter 7 for 12 Lead Training -Acquisition-

1. Chapter 7 for 12 Lead Training-Acquisition- Ontario Base Hospital Group Education Subcommittee 2008 TIME IS MUSCLE

2. Acquisition REVIEWERS/CONTRIBUTORS Neil Freckleton, AEMCA, ACP Hamilton Base Hospital Jim Scott, AEMCA, PCP Sault Area Hospital Ed Ouston, AEMCA, ACP Ottawa Base Hospital Laura McCleary, AEMCA, ACP SOCPC Tim Dodd, AEMCA, ACP Hamilton Base Hospital Dr. Rick Verbeek, Medical Director SOCPC AUTHOR Greg Soto, BEd, BA, ACP Niagara Base Hospital 2008 Ontario Base Hospital Group

3. Chapter 7 Objectives • Identify the goals for acquiring 12 Lead ECG • Describe differences between 3-Lead & 12-Lead ECG • Locate placement of limb & chest leads • Explain causes of artifact and list remedies • Describe dignity issues involvedin exposing chest and list solutions

4. Acquisition Does NOT have to increase scene time • PHECG studies have found on scene times to increase minimally (0 - 3 minutes) • Scene time with PHECG improves with practice and scene organization

5. Acquisition Goals • Clear • Accurate • Fast

6. 12 Lead ECG • Not just some extra wires • Very different internal design due to filters

7. 3-Lead ECG • Monitor Quality

8. 12-Lead ECG • Diagnostic Quality

9. Diagnostic Quality • Produces more accurate ST segments and T waves • More sensitive to artifact

10. Diagnostic Quality • You may have to take steps to improve ECG quality. More on this later

11. Leads Precordial Chest Leads • V1, V2 • V3, V4 • V5, V6 Limb Leads • I, II, III • AVR, AVL, AVF

12. Lead Placement Lead placement is critical • If not placed correctly (even by one interspace) the resulting ECG will exhibit changes that could be misconstrued as “abnormal” and profoundly affect patient care

13. Limb Lead Placement • Place leads on limbs • Away from major muscles or arteries • Have patient remain still during 12 lead acquisition (to reduce artifact)

14. Limb Lead Placement • Place electrodes on the limbs if there is a 12 lead in the patient’s future – highly preferable to torso placement

15. Limb Lead Placement • Reasons to place on the torso? • Fracture • Amputation • Artifact • If Limb Leads are placed on the torso make sure to document this directly on the 12 Lead ECG

16. Limb Leads • aVR should be negative • If aVR is upright, check for reversed limb leads

17. Precordial Chest Leads For every person, each precordial lead placed in the same relative position • V1 - 4th intercostal space, R of sternum • V2 - 4th intercostal space, L of sternum • V4 - 5th intercostal space, midclavicular • V3 - between V2 and V4, on 5th rib or in 5th intercostal space • V5 - 5th intercostal space, anterior axillary line • V6 - 5th intercostal space, mid-axillary

18. Chest Lead Placement

19. Chest Lead Placement • V1 is placed in the 4th intercostal space to the right of the sternal boarder • To find the 4th intercostal space feel for the clavicle • Just below the clavicle is the 2nd rib, then 3rd and 4th rib • Between the 4th rib and the 5th rib is the 4th intercostal space • V2 is placed to the left of the sternal boarder in the 4th intercostal space

20. Chest Lead Placement • V4 is placed next in the 5th intercostal space in the mid-clavicular line • Find the half way mark on the left clavicle and move down one rib so V4 is between the 5th and 6th ribs • V3 is placed after V4 and is simply placed in between V2 and V4 either on the 5th rib or in the 5th intercostal space

21. Chest Lead Placement • V5 is placed in the 5th intercostal space and the anterior axillary line • To find the anterior axillary line lay the patient’s left arm at their side and follow the crease line in their armpit down the front of their chest • V6 is placed in the 5th intercostal space in the mid-axillary line

22. V6 V3 V5 V4 V1 V2 Chest Lead Placement V1: 4th intercostal space to the right of the sternum V2: 4th intercostal space to the left of the sternum V3: directly between V2 and V4 V4: 5th intercostal space at the left mid-clavicular line V5: level with V4 at the anterior axillary line V6: level with V5 at the mid-axillary line

23. Exposing the Chest & Pt Dignity Where required: • Remove clothing only if necessary • Replace with a gown or a sheet With practice: • Chest leads can be placed on adult women without exposing breasts • Work around bras where prudent When placing electrode for V4, use the back of a gloved hand to lift a women’s left breast AFTER informing her. It is difficult to construe this action as sexual contact vs. using the front of a cupped hand.

24. Video - Acquisition Play 12 Lead ECG Acquisition video here

25. Reduce Artifact:Skin Prep • Dry moist skin • Clip or shave excess hair • Abrade dead skin with skin prep tape, plastic backing of 12 lead stickers or dry 4x4 gauze

26. Other Causes of Artifact • Patient movement • Cable movement • Vehicle movement • Electro-Magnetic Interference

27. Patient Movement • Make patient as comfortable as possible: • Supine preferred • Sitting most common with chest pain/SOB patients

28. Patient Movement • Check for subtle movement: • Toe tapping, shivering • Look for muscle tension: • Hand grasping rail, head raised to “watch” • Coach the patient: • Lie still, stop talking, breath slow and quiet

29. Cable Movement • Some “slack” between monitor and patient is needed • Not too much “slack” (leads can come off electrodes)

30. EMI • Electro-Magnetic Interference • EMI can interfere with electronic equipment: • Airlines prohibit use of electronic equipment during take-off

31. EMI • Maintain awareness of possible EMI interference: • Cell phones • Radios • Most electrical devices • Fluorescent lights

32. Clear ECG Things to look for… • Little or no artifact • Steady baseline • Which is worse for reading 12 Lead ECG?

33. Oh Oh!! Now What?

34. Ahhh! Much Better Note: the baseline straightened out by simply repositioning the patient cables and clipping them onto the sheet.

35. QUESTIONS?

36. START QUIT Well Done! Education Subcommittee