1. Issued April 2008 Authors & Reviewers: Karen L Johnson, RN, MSN, PhD Kate M. Moore, RN, MS, ND, CCRN, ACNP Practice Alert ST Segment Monitoring

2. Practice Alert - ST Segment Monitoring 2 Lecture Content  Skin preparation  Lead placement and selection  Patient positioning  Measuring the ST segment  Pediatric specific  Recommendations

3. Practice Alert - ST Segment Monitoring 3 Skin Preparation  Clip excessive hair before placing electrodes  Clean skin with alcohol or washcloth to remove skin oils and/or debris  Mark locations with indelible ink to assure that if electrodes are moved they can be replaced in their original locations.

4. Practice Alert - ST Segment Monitoring 4 Electrode Placement  Limb leads (I,II,III)  Place to decrease muscle artifact during limb movement  Placement  Right Arm (RA) infra-clavicular fossa close to right shoulder  Left Arm (LA) infra-clavicular fossa close to left shoulder  Left Leg (LL) below rib cage on left side of abdomen  Ground (RL)  Precordial Leads - depends on patient’s needs

5. Practice Alert - ST Segment Monitoring 5 ST Segment Monitoring  ST segment monitoring can detect silent ischemia in asymptomatic patients.  Although the impact of ST segment monitoring on patient outcomes is not known, when ST segment monitoring is used, it is imperative that accurate data are obtained.

6. Practice Alert - ST Segment Monitoring 6 Lead Selection  Monitoring ST segment changes in 12 leads provides the most accurate data for identification of ischemic events.  If only two leads are available for ST segment monitoring, use leads III and V 3 (unless otherwise indicated)

7. Practice Alert - ST Segment Monitoring 7 ST Segment Fingerprint  If 12 lead monitoring is not available, use the patient’s “ST Fingerprint”.  Defined as the pattern of ST segment elevation and/or depression unique to a particular patient based on the anatomic site of coronary occlusion  Can be obtained during STEMI or PCI

8. Practice Alert - ST Segment Monitoring 8 Other Considerations  If the ST fingerprint is not known, use leads III and V 3.  For patients without definitive ACS, with suspected of having or being ruled out for ACS, use leads III and V 5.  For non-cardiac surgical patients lead V 5 is valuable for identifying demand-related ischemia.

9. Practice Alert - ST Segment Monitoring 9 Patient Positioning  Evaluate ST segment with the patient in the supine position.  Change in body position can alter ST segment, mimic ischemia.  If ST alarm sounds with patient in side- lying position, return patient to supine. If deviation persists in supine may indicate ischemia.

10. Practice Alert - ST Segment Monitoring 10 Measuring the ST Segment  J Point  The junction of the QRS complex with the ST segment  Measure ST segment changes 60 ms beyond the J point Flanders SA. Continuous ST-segment monitoring: Raising the bar. Crit Care Nurs Clin N Am 2006;18(3):172

11. Practice Alert - ST Segment Monitoring 11 Alarm Parameters  Patients at high risk for ischemia  Set ST segment alarm parameters 1 above and below baseline ST segment  Stable Patients  Set ST segment alarm parameters 2 mm above and below baseline ST segment

12. Practice Alert - ST Segment Monitoring 12 Cause for Concern  ST depression or elevation of 1-2 mm that lasts for at least one minute can be clinically significant and warrants further patient assessment. Flanders SA. Continuous ST-segment monitoring: Raising the bar. Crit Care Nurs Clin N Am 2006;18(3):172 5 mm depression 4 mm elevation

13. Practice Alert - ST Segment Monitoring 13 Pediatric Specific Information  For neonates and infants the TP segment may be a more accurate isoelectric point than the PR segment.  For neonates and infants an ST elevation or depression of 1 mm or greater is considered clinically significant.

14. Practice Alert - ST Segment Monitoring 14 Need Further Assistance? For more information or further assistance, please contact a clinical practice specialist with the AACN Practice Resource Network. Email: practice@aacn.org Phone: (800) 394-5995