1 / 21

The Science of CPR

The Science of CPR. Many thanks to Dr. Kudenchuk for sharing his slides. CPR Prior to Shock First rhythm VF; n=1117. 50 40 30 20 10 0. p=0.04. “CPR first” 1994-96, n=478. % Survival. “Shock first” 1990-93, n=639. 1 2 3 4 5 >5.

dustin
Download Presentation

The Science of CPR

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. The Science of CPR Many thanks to Dr. Kudenchuk for sharing his slides

  2. CPR Prior to Shock First rhythm VF; n=1117 50 40 30 20 10 0 p=0.04 “CPR first” 1994-96, n=478 % Survival “Shock first” 1990-93, n=639 1 2 3 4 5 >5 1st Unit Arrival Interval (min) 1990-93 n=22 91 205 164 86 71 1994-96 n=14 80 164 114 65 41 Cobb LA et al. JAMA 1999;281:1182-1188

  3. Compression • Increased intrathoracic pressure • Ejects blood from heart and lungs • “Good” compression increases forward output and BP • Decompression (recoil) • Decreased intrathoracic pressure • Refilling of heart and lungs • “Good” recoil  vacuum refillingforward output

  4. Hemodynamics of CPR Compression (“systole”) mm Hg Decompression (“diastole”) 60 RT ATRIUM Aorta 40 Organ perfusion Heart + organ perfusion 0 EXTRATHORAIC VEINS LEFT VENTRICLE RT ATRIUM Criley JM et al. Circulation 1986;74(IV):42-50.

  5. Coronary Perfusion Pressure and ROSC in Human CPR n=100 patients with cardiac arrest 100% 80% 57% 50% 55+ (normal) 40-45 25-39 No ROSC n= 76 CorPP 8.4±10 mm Hg ROSC n=24 CorPP 25.6±7.7 mm Hg 36% 20-24 Coronary perfusion pressure (CorPP) Coronary perfusion pressure (CorPP) 15-19 0% 0-14 *CorPP = Aorta – RA pressure gradient during relaxation (diastolic) phase of precordial compression Paradis NA., et al. JAMA 1990;263:1106-1113

  6. n = 60 consecutive VF resuscitations/shock • 63% men, 65 y/o • Time to 1st shock = 3.7min • Measurements • Compression depth = mm during 30 sec before 1st shock • Outcomes • Successful shock = VF terminated ≥ 5 sec • ROSC = organized rhythm/pulse/BP ≥ 20 min Edelson DP et al. Resuscitation 2006;71:137-45

  7. Effect of CC Depth on Shock Success ORadj*1.99/↑5 mm compression depth (95%CI 1-08-3-66, p=0.028) *Arrest location, age, sex, time-to-shock † † AHA recommendations 1.5-2” (4-5 cm) Edelson DP et al. Resuscitation 2006;71:137-45

  8. The Price of CPR Pauses 30 compressions Aorta RA 16 secs 3 secs CPR “systole” CPR “diastole” Paused CPR

  9. CPR Performance: Observed vs Perceived n=30 (19 EMTs, 11 Paramedics) Manikin study 90% (88-90) 82% (75-90) 80% (75-90) 75% (70-90) (25th-75th quartiles) (50/50) Correct CPR Performance Parameters Aufderheide TP et al. Resuscitation 2005;64:353-62

  10. CPR Performance: Observed vs Perceived n=30 (19 EMTs, 11 Paramedics) Manikin study NSD 99% (85-100) p=0.002 p=0.01 p=0.02 90% (88-90) 82% (75-90) 80% (75-90) 75% (70-90) 47% (42-48) (25th-75th quartiles) 26% (24-57) 8% (7-60) (50/50) Correct CPR Performance Parameters Aufderheide TP et al. Resuscitation 2005;64:353-62

  11. n=176 adults with out-of-hospital cardiac arrest • Automated resuscitation monitoring • Compression rate, depth, “hands off” time • Ventilation rate • ECG • Events Wik L et al JAMA 2005;293:299-304

  12. Quality of CPR During Out-of-Hospital Cardiac Arrest n=176 Vs AHA Guidelines chest compression 100 ± 10/min (75 @ 30:2) Vs AHA Guidelines compression depth 38-52 mm (1.5-2”) 60  25 64  23 49%  21 48%  18 34  9 35  10 ~12% @ 30:2 † * † % time without spontaneous circulation or chest compressions *Average # compressions given per minute vs instantaneous rate at which compressions, when given, were administered (120  20) Wik L et al JAMA 2005;293:299-304

  13. 20 instrumented swine • 7 minutes of unsupported VF CPR + AED “Hands-off” interval prior to each shock (mimicking analysis and charge interval of AEDs (10-19secs)) 3 secs 10 secs 15 secs 20 secs Yu T et al. Circulation 2002;106:368-372

  14. Effect of Interrupted Precordial Compression on Resuscitation Outcome Successfully Resuscitated p<0.01 p<0.05 100% p<0.05 80% 40% 0 Seconds of Interrupted CPR n=5 per group Yu T et al. Circulation 2002;106:368-372

  15. n=9 instrumented swine • 6 minutes untreated VF  standard CPR* x 3 min  CPR with 75% • recoil (residual 1.2 cm sternal compression @ end decompression) • x 1 min  standard CPR* x 1 min  defib x 3  ACLS *Standard CPR = CC @100/min, 50% duty cycle, 5 cm depth, full (100%) recoil, 15:2 ratio Yannopoulos D et al. Resuscitation 2005;64:363-72

  16. Effect of Incomplete Chest Decompression On Coronary and Cerebral Perfusion Pressures n=9 instrumented swine  std CPR (100% recoil) x 3’  CPR (75% recoil) x 1’ *† *† p<0.05 % Chest recoil † * * p<0.05 * mm Hg Critical pressure for ROSC * † * *(Ao Diastolic-RAP) †(MAP – mean ICP pressure) Yannopoulos D et al. Resuscitation 2005;64:363-72; Paradis et al JAMA 1990;263:3257-8

  17. New Protocol Importance of High-PerformanceResuscitation Percent Survival from Witnessed VF Rhythm 60 50 40 48% percentsurvival 30 35% 20 10 0 2000 - 2004 2005 - 2009

  18. Take home points • Quality of CPR is critical • Rate • Depth • Recoil • High Density CPR(also ‘high performance CPR’) • Achieved with a carefully choreographed approach • Chest compressions must occur 90% of the time

  19. Annual Utstein Survival for Chelan/Douglas Counties *Incomplete data for 2010

More Related