1 / 18

Defibrillation and Cardioversion

Defibrillation and Cardioversion. EMS Professions Temple College. Defibrillation. Mechanism Current depolarizes myocardium Induces asystole temporarily Allows one pacemaker to regain control. Defibrillation. Factors to consider Duration of VF

errol
Télécharger la présentation

Defibrillation and Cardioversion

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Defibrillation and Cardioversion EMS Professions Temple College

  2. Defibrillation • Mechanism • Current depolarizes myocardium • Induces asystole temporarily • Allows one pacemaker to regain control

  3. Defibrillation • Factors to consider • Duration of VF • The longer VF lasts, the harder it is to cure • The quicker the better • Shock early-Shock often • Likelihood of resuscitation decreases 7-10% with each passing minute

  4. Defibrillation • Factors to consider • Myocardial environment/condition • Hypoxia, acidosis, hypothermia, electrolyte imbalance, drug toxicity impede conversion • Do NOT delay shock trying to correct problems

  5. Defibrillation • Factors to consider • Heart size/body weight • Pedi requirement lower than adult • 2 J/kg initial shock • 4 J/kg repeat shocks • Direct size/energy relationship in adults unknown • 200 to 360 J

  6. Defibrillation • Previous countershock • Repeated shocks lower resistance • Give three initial shocks in 30-45 sec • One quickly after another with little time between

  7. Defibrillation • Factors to consider • Paddle size • Adults (large paddles) • 10-13 cm diameter • Pediatric (small paddles usually < 1 yr) • Children 8 cm • Infants 4.5 cm

  8. Defibrillation • Use largest size that completely contacts chest without paddles touching • Small paddles: concentrate current, burn heart • Large paddles: reduce current density

  9. Defibrillation • Paddle placement • One to right of sternum below clavicle; Other to left of left nipple in anterior axillary line • Reversing paddles marked “apex--sternum” does NOT affect defibrillation • AP placement can be used to defib small children with adult paddles

  10. Defibrillation • Paddle-skin interface • Cream, paste, saline pads, gelled pads • Decreases resistance to current flow • Avoid smearing or running: “bridges” charge • NEVER use alcohol!!!

  11. Defibrillation • Paddle contact pressure • Firm pressure of 25 pounds • Deflates lungs; Shortens current path • Do not lean on paddles; They slip

  12. Cardioversion • Definitions • Cardioversion • Use of electrical shock to interrupt tachycardia • Used in Non-Arrest patients only • Only VF/VT (pulseless) can be defibrillated

  13. Cardioversion • Definitions • Synchronized cardioversion • Timing of shock to avoid peak of T-wave • Prevents VF caused by delivering shock during vulnerable period

  14. Cardioversion • Indications • Tachyarrhythmias which: • Cause or worsen hemodynamic compromise • Cause or worsen ischemic heart disease • Are resistant to drug therapy

  15. Cardioversion • Procedure • Oxygen, ECG monitor, IV • Patient must be on leads to cardiovert • Sedate with Valium or Versed • Do NOT make patient unresponsive

  16. Cardioversion • Procedure • Activate synchronizer • Observe marking of complexes • May need to unsynchronize if: • Random synching occurs • Double-synching occurs

  17. Cardioversion • Procedure • Charge to desired energy setting • Depress buttons; Hold until discharge occurs • If VF occurs, unsynchronize before defibrillating

  18. Cardioversion If a patient is in VF, why might the defibrillator not discharge if the synchronizer is on?

More Related