1. Noninvasive Pacing – What You Should Know

2. Hey! Maybe we should try pacing!

3. Evidence Based Medicine What articles or literature support the use of pacing in the Pre-hospital arena?

4. The Original Pacing Study!

5. Other Important Papers on Pacing “Prehospital TCP for symptomatic bradycardia” Pacing and Clinical Electrophysiology, 1991 51 pts tot., 27 paced Survival to dischg if palpable pulse on paramedic arrival? 80% in TCP vs 0% (p=0.02) TCP clearly benefits the bradycardic pt with pulse “The Benefits of Electricity: TCP in EMS” Emerg. Med. Svcs, 2002 Informational article supporting the use of TCP in the bradycardic patient and now also in children

6. ACLS Guidelines Last revised in 2005Last revised in 2005 Emphasis on early pacing for symptomatic bradycardiaEmphasis on early pacing for symptomatic bradycardia Initial pacing method of choice in emergency cardiac careInitial pacing method of choice in emergency cardiac care Quickly initiated and least invasiveQuickly initiated and least invasive

7. Cardiac Conduction System Sinoatrial (SA) Node Atrioventricular (AV) Node Left Bundle Branches Right Bundle Branch Purkinje Fibers P = Atrial Depolarization QRS = Ventricular Depolarization T = Ventricular Repolarization PT QRS

8. Failure of the Conduction System May occur anywhere in the systemMay occur anywhere in the system The farther down the system – the slower the heart rateThe farther down the system – the slower the heart rate Multiple causesMultiple causes ResultsResults –bradycardia –asystole

9. Treatment of Symptomatic Bradycardia AtropineAtropine Noninvasive pacing (Class 1 intervention)Noninvasive pacing (Class 1 intervention) DopamineDopamine EpinephrineEpinephrine

10. Asystole Pacing is no longer recommended for aystolePacing is no longer recommended for aystole

11. MVEMSA Pacing Protocol INDICATIONS: –Symptomatic Bradycardia –3rd degree Complete Heart Block or 2nd degree Mobitz type 2 RELATIVE CONTRAINDICATIONS: –Hypothermia –Hemodynamically stable awake patients. –Non-intact skin at the site of the electrode placement

12. Temporary Pacing Techniques Epicardial Transesophageal Trancutaneous

13. Noninvasive Pacing Self-adhesive electrodes applied to the skin Advantages –easily initiated by nurse, paramedic and MD –not invasive/cost effective –used when invasive pacing is contraindicated / undesirable Disadvantages –discomfort

14. Applications for Noninvasive Pacing Emergency Use Alternative to invasive pacing Standby Use

15. Emergency Use of Noninvasive Pacing Therapeutic bridge to stabilize the patient and plan further care –symptomatic bradycardia unresponsive to drugs –cardiac arrest

16. Standby Use of Noninvasive Pacing Patient is clinically stable but may decompensate –cardiac patient undergoing surgery –acute MI with heart block –permanent pacemaker surgery –cardiac catheterization/angioplasty –post cardioversion bradycardias We WILL NOT be using Pacing for these purposes!

17. Pacing Procedure Preparing the patient and familyPreparing the patient and family ECG electrode placementECG electrode placement Pacing electrode placementPacing electrode placement Selecting the rate, mode and currentSelecting the rate, mode and current Assessing for captureAssessing for capture

18. Preparing the Patient and Family Explain procedureExplain procedure –discomfort with cutaneous nerve and skeletal muscle stimulation Sedation or analgesia often neededSedation or analgesia often needed

19. ECG Electrodes Skin prepSkin prep –remove excessive chest hair –clean, dry, and gently abrade skin Place ECG electrodes away from pacing electrodesPlace ECG electrodes away from pacing electrodes Use quality ECG electrodesUse quality ECG electrodes

20. Pacing Electrodes Skin prep importantSkin prep important –clip excessive chest hair –clean skin with soap and water –dry skin and gently abrade Place pacing electrodes on clean, dry skinPlace pacing electrodes on clean, dry skin

21. Anterior-Posterior Electrode Placement Most commonMost commonplacement PreferredPreferred Improves conduction to myocardiumImproves conduction to myocardium

22. Anterior Electrode Placement

23. Posterior Electrode Placement

24. Anterior-Posterior Electrode Placement Anterior-Posterior Electrode Placement

25. Anterior-Lateral Electrode Placement Alternate placementAlternate placement Convenient placement in cardiac arrestConvenient placement in cardiac arrest Usually the SECOND choiceUsually the SECOND choice

26. Anterior-Lateral Electrode Placement

27. Noninvasive Pacing Modes DemandDemand Non-demandNon-demand (asynchronous or fixed) (asynchronous or fixed)

28. MVEMSA Protocol Assemble the required equipment. Explain the procedure to the patient. Connect the patient to a cardiac monitor and obtain a rhythm strip. Obtain baseline vital signs.

29. MVEMSA Protocol Provide for patient sedation using Versed 2mg slow IV push, titrate in 1 mg increments, to a maximum of 6mg. DO NOT delay pacing to give sedation if the patient is critically ill and such delay may cause a detriment in patient’s care. Apply pacing electrodes (avoid large muscle masses) and attach the pacing cable and pacing device, per manufacturer’s recommendations. Select the pacing mode to demand or non-demand mode, if applicable. Set the pacing rate to 80 BPM. Set the milliamps (mA) at zero.

30. MVEMSA Protocol Activate the pacing device and increase the milliamps as tolerated (observe the patient and ECG) until capture is achieved (capture is the point when the pacemaker produces a pulse with each QRS complex). Obtain rhythm strips as appropriate. Continue monitoring the patient and anticipate further therapy.

31. Demand pacing Delivers impulse only when neededDelivers impulse only when needed Sensing inhibits pacemakerSensing inhibits pacemaker Not used in Pre-hospital environmentNot used in Pre-hospital environment

32. Non-demand Pacing Delivers current at selected rate and ignores intrinsic beatsDelivers current at selected rate and ignores intrinsic beats Backup mode for oversensing and motion artifactBackup mode for oversensing and motion artifact

33. Selecting Rate and Current Assure proper QRS sensingAssure proper QRS sensing Set pace rate high enough for adequate perfusionSet pace rate high enough for adequate perfusion Increase current (mA) until electrical captureIncrease current (mA) until electrical capture

34. Access Pacer (Green) mode (Zoll) The Pacer (Green) mode is accessed by turning the Selector Switch counter- clockwise Milliamps are the type of current which are utilized in this mode No AED capability or ANALYZE button can be used in this mode

35. Pacer Mode: Rate Dial Pacer markers (PPM) indicate the rate set to attempt to capture the ventricle Default settings of 70 PPM and 0 mA are displayed upon access of Pacer Mode To increase or decrease pacer marker (PPM) turn the Pacer Rate Dial

36. Pacer Mode: Output Dial Turn the Pacer Output dial to adjust the level of discharged milliamps. If capture is achieved, the PPM will have a wide complex reflecting ventricular contraction following the thin PPM rate marker

37. Assessing for Capture Electrical captureElectrical capture –depolarization of the ventricles –confirmed by ECG display Mechanical captureMechanical capture –contraction of the myocardium –confirmed by pulse and improved cardiac output Both must occur to benefit the patientBoth must occur to benefit the patient

38. Electrical Capture

41. Intermittent Electrical Capture

43. Determining Mechanical Capture Check pulse (Doppler helpful) Look for increase in blood pressure

44. Determining Mechanical Capture Use of pulse oximetry during pacing may assist in determining capture PLEASE DON’T FORGET THIS IMPORTANT POINT!

45. Pacemaker Blanking Periods

46. Artifact During Pacing Artifact may mimic electrical captureArtifact may mimic electrical capture

47. Artifact During Pacing Artifact may mimic electrical captureArtifact may mimic electrical capture

48. Artifact During Pacing ECG electrodes pick up artifact from pacing currentECG electrodes pick up artifact from pacing current Artifact is sometimes displayed on monitorArtifact is sometimes displayed on monitor May mask VF and distort response to pacingMay mask VF and distort response to pacing Blanking period attempts to filter out artifact and limit distortion of ECG signalBlanking period attempts to filter out artifact and limit distortion of ECG signal

49. Troubleshooting DiscomfortDiscomfort Failure to captureFailure to capture UndersensingUndersensing OversensingOversensing

50. Discomfort Explain procedureExplain procedure Reposition anterior electrodeReposition anterior electrode Use sedation or analgesiaUse sedation or analgesia

51. Failure to Capture Increase currentIncrease current Reposition electrode across precordiumReposition electrode across precordium Correct metabolic acidosis, hypoxiaCorrect metabolic acidosis, hypoxia Check pacemaker functionCheck pacemaker function

52. Factors Possibly Leading To High Capture Thresholds HypoxiaHypoxia Acidosis Acidosis Air, fluid in the chestAir, fluid in the chest Emphysema, pericardial effusionEmphysema, pericardial effusion Positive pressure ventilationPositive pressure ventilation IschemiaIschemia Mild HypothermiaMild Hypothermia

53. Undersensing Increase ECG sizeIncrease ECG size Select different ECG leadSelect different ECG lead Reposition ECG electrodesReposition ECG electrodes Re-prep skin and replace ECG electrodesRe-prep skin and replace ECG electrodes

54. Oversensing Decrease ECG sizeDecrease ECG size Select different ECG leadSelect different ECG lead Reposition ECG electrodesReposition ECG electrodes Select non-demand mode if availableSelect non-demand mode if available

55. Pacing Success

56. Summary - Noninvasive Pacing Valued and respected technique in emergency cardiac careValued and respected technique in emergency cardiac care Basic principles of invasive pacing apply to noninvasive pacingBasic principles of invasive pacing apply to noninvasive pacing Allows rapid initiation of emergency pacingAllows rapid initiation of emergency pacing

57. “Buying Time”