Current trends in CPBR: Techniques and underlying mechanism

1. Current trends in CPBR:Techniques and underlying mechanism Dr. GauravDhakate University College of Medical Sciences & GTB Hospital, Delhi

2. Anyone, anywhere, can now initiate cardiac resuscitative procedures. All that is needed are two hands. JAMA 1960

3. History : • 1960 : Kouwenhoven et al reported survival of 14 patients of cardiac arrest following closed cardiac massage. • 1960 : combination of chest compression and rescue breath introduced. • 1962 : direct-current , monophasic waveform defibrillation was described. • 1947 : Beck successfully defibrillated his first patient, a 14-year-old boy whose heart went into fibrillation after an operation.

4. 1978 : The first AED was originally designed and created by American biomedical engineer Joshua L. Koelker and Italian emergency medical professional Jordan M. Blondino. 2010 AHA ECC guidelines mark the 50th anniversary of CPR.

5. What is CPR ? • Cardio pulmonary resuscitation is an emergency medical procedure performed on a victim of cardiac or respiratory arrest and it consists of rapid chest compressions to maintain blood circulation, along with artificial respiration.

6. Purpose : To maintain circulation to brain and heart thereby prevent the tissue death and brain damage until cardiac activity is restarted. Goal : • Support & restore effective oxygenation, ventilation and circulation with return of intact neurological function. Intermediate Goal: • Return of spontaneous circulation (ROSC)

7. 3 phases of cardiac arrest : Following a cardiac arrests, 3 distinct phases are characterized in the body: • Electrical phase : first 4 – 5 mins, defibrillation has most dramatic effect and it is highly successful. • Haemodynamic phase : next 4 – 5 mins. Fibrillating heart losses all ATPs. • Metabolic phase : CPR is only effective if commenced within 6 minutes after the blood flow stops. Hypothermia helps in prolonging this phase.

8. Recommendations for CPR: • AHA guidelines every 5 yrs. • The guidelines are based on strength of available evidence. • These are based on most current and comprehensive review published by the 2010 ILCOR International consensus on CPR and ECC science with treatment recommendations. • ILCOR is a body of 7 international resuscitation organizations (AHA, ERC, IAHF, HSFC, ANZCOR, RCSA, RCA).

9. Cont. • Included 356 resuscitation experts from 29 countries. • Took 36 months before the consensus. • These experts produced 411 scientific evidence reviews on 277 topics in resuscitation and emergency cardiovascular care.

10. Approaches to resuscitation: • BLS • ACLS

11. SCA • LEADING CAUSE OF DEATH • Etiologies: Cardiac vs non cardiac • Circumstances out of hospital and in the hospital SCA. • Settings : witnessed or unwitnessed . Single approach for maximum benefit….. Chain of survival

12. Chain of survival

13. Early access Early access to the victim • Scene safety: Rescuer, victim. • Call help: outside the hospital102, inside the hospital, activate the code. • Get AED

14. Early CPRComponents of BLS: C A B Defibrillation A B C Defibrillation WHY THE CHANGE? • C : circulation • A : airway • B : breathing

15. The change from “A-B-C” to “C-A-B” • Most common cause of witnessed fall: cardiac arrest. • Most common cause of cardiac arrests: VF, pulseless Ventricular tachycardia. • key to survival: chest compression and early defibrillator. • Securing airway is most difficult part. • Hesitancy on part of rescuer to provide breaths. • This new sequence leads to early starting of most important part of therapy with minimal delay in ventilation. • Healthcare providers could tailor the sequence of rescue action to its cause.

16. BLS Primary survey • Support/ restore effective oxygenation, circulation and ventilation until ROSC or ACLS team takes over. • No advanced interventions- airway tech./ drugs (use safety measures). • Early CPR and early defibrillation

17. BLS Primary Survey

18. BLS Primary Survey….components

19. Chest Compressions • Patient positioning: Firm and hard surface (ground, table/ hard bed) deflate air/ water mattresses. • Rescuer's position: Level with patient, elbows vertically straight and locked, shoulders directly above the hands, heel of one palm over the other. • Site : sternum in inter-mammary line. • Depth: at least 2 inches • Rate: at least 100 per minute (5 cycles of 30:2-C:V over 2 min.). • Allow complete chest recoil.

20. CPR techniques and devices : • High frequency chest compression. • Open chest CPR. • Interposed abdominal compression CPR. • Cough CPR. • Prone CPR. • Precordial thump. • Percussion pacing.

21. CHEST COMPRESSIONS30 CHEST COMPRESSIONS

22. Mechanism of action of chest compressions: • Thoracic pump theory • Cardiac pump theory

23. Hands off- time • Less than 10 sec. • Specific interventions: defibrillation, advanced airway, moving the patient. Avoid : • Prolonged rhythm analysis • Frequent pulse checks • Too long breaths • Unnecessary moving the pt.

24. Basic airway skills • Head tilt- chin lift • Jaw thrust without head extension (? Cx spine trauma) • Mouth- to- mouth ventilation • Mouth- to- nose ventilation • Mouth- to- barrier device (pocket mask) • Bag-mask ventilation

25. Breathing Assessed at beginning while assessing responsiveness. Look, Listen & feel ……has been removed Each breath: • 1 Sec • Visible chest rise (ventilate not hyperventilate….) • Allow similar time for exhalation. • C:V 30:2 • No chest rise after 1st breath- reposition airway/ mask seal . • No chest rise after 2nd breath- resume chest compression. Compression only CPR for bystander rescuer

26. Early defibrillation How does a shock act? • High energy current- stuns the myocardium • Pacemaker: SA node restarts the rhythm Why early? Will help only if myocardium is still viable. • Chance of survival : decline more gradually • 7%-10% /min…..if no CPR • 3%-4%/ min from collapse to defib if CPR is provided. • Like wise the decline is more gradual when early defib is done.

27. AED:

28. D:Defibrillators: Unresponsive victim No pulse No breathing Rhythm shockable: VF Pulseless VT

29. Defibrillators Types : Manual defibrillators, Automated external defibrillators (AED). • Monophasic / biphasic. Adult and child (1-8 yrs). Infants: Manual defib is preferred. >4 J/kg- 9J/kg have effectively defibrillated children and animal models.

30. One shock f/b CPR has better results . Less time consuming. Optimal energy level: undecided. Monophasic manual defibrillators: 360 J f/b 360 J subsequently. Biphasic defibrillators: Better and safe. No studies on exact initial energy levels. Use manufacturers guidelines (120 J – 200 J). Subsequent shocks: use same or higher energy levels. AED: as programmed.

31. Defib • Pad sizes: • Adult • Paediatric • Adult pads may be used in paediatric victims..not vice- versa Special situations: • Hairy chest, • Pacemakers, • Medication patches, • Drowning.

32. After D: • IMMEDIATE CHEST COMPRESSIONS…… WHY? RETURN OF ELECTRICAL ACTIVITY ……. CONTRACTILITY IS LIKELY TO BE LIMITED ..NOT SUFFICIENT ENOUGH TO PUMP BLOOD FORWARD.

34. Respiratory arrest • Unresponsive victim who is not breathing normally but has a pulse. • Provide ventilations @ 10-12 breaths /min (1 breath every 5-6 secs). • Definitive airway device in place ventilate @ 8-10 breaths/min (1 breath every 6-8 secs). • Assess circulation every 2 minutes and maintain airway with a chin lift and call for help.

35. Adult/child/infant recommendations • table

36. WHEN NOT TO START CPR • Unsafe scene • Valid DNAR order (?). • Signs of death (rigor mortis, decapitation or dependent lividity).

37. WHEN TO STOP CPR • ROSC • Trained help arrives • Too exhausted to continue • Unsafe scene • DNAR orders received (?). • Provide longer help if hypothermic or suspected toxins.

38. ACLS secondary survey Components • C : CIRCULATION. • A: ADVANCED AIRWAYS- ETT, LMA, Combi-tube, Laryngeal tube • B : BREATHING. • D: DRUGS. DIFF DIAGNOSIS.

39. ACLS Secondary Survey…….components

41. Common Reversible Causes

42. C: Circulation Advanced circulatory interventions: Access for drug administration: IV/ IO/ ET. IV: Preferred route, follow drug admin by 20 ml fluid bolus, elevate limb for 10-20 secs. IO: If iv route not available. All drugs given iv can be given IO. ET: Ideal dose not known, 2-2.5 X IV dose. Dilute in 5-10 ml NS. (Epi., vasopressin, atropine, lidocaine naloxone).

43. Circulation Drugs to control heart rhythm and blood pressure. BP: Adrenaline, Vasopressin, Dopamine. • Adrenaline: α adrenergic vasoconstriction 1mg iv/ io every 3-5 mins. • Vasopressin: nonadrenergic peripheral vasoconstriction, 40 units iv/ io single dose, Replaces 1st or 2nd dose of adrenaline. • Dopamine: 2-10 µg/kg/min.

44. Drugs for rhythm Rhythm: Atropine, Lidocaine, Amiodarone, Magnesium, Adenosine. • Atropine: Bradycardia: 0.5 mg upto a total of 3mg. • Amiodarone: VF/ pulseless VT unresponsive to CPR, shock and vasopressor. 300 mg iv/ io first dose, 150 mg iv/ io 2nd dose if reqd.

45. Drugs for rhythm • Lidocaine: alternative to amiodarone. 1-1.5 mg/kg iv/ io 1st dose, rpt 0.5-0.75 mg/kg upto total 3 doses or 3mg/kg. • Magnesium: terminate/ prevent torsades- de pointes, known/ suspected low magnesium (alcoholism, malnutrition). load 1-2 g iv/ io in 10 ml 5% Dex 5-20 mins. • Adenosine: Narrow complex tachy (SVT), undiff. Regular, monomorphic wide- complex tachy. 6 mg rapid flush large vein, if reqd 12 mg twice after 1-2 min. IV injections f/b 20 ml fluid bolus and raising the arm.

46. A= Airway Head tilt- chin lift/ jaw thrust Basic airway adjuncts: • OPA: Use only in unconscious pts. • NPA: When OPA is difficult/ impossible.

47. Airway Advanced Airway interventions: Endotracheal tube. Laryngeal mask airway, Laryngeal tube, Combitube (esophageal-tracheal combitube)

48. Breathing • 1 Breath every 5 -6 sec (10-12 breaths/ min). • Ventilation adequate? • Advanced airway ……required? • Advanced airway in place: 1 Breath every 6-8 sec (8-10 breaths / min). • Confirm placement of device, secure, confirm again- clinical (visible chest rise, 5 pt auscultation), Et CO2. • Compressions and ventilations are independent ( no more C:V 30:2 cycles).

49. PULSELESS ARREST • VF shockable rhythm • Pulseless VT • Asystole non shockable rhythm • PEA