Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Pediatrics Grand Rounds 17 June 2011 University of Texas Health Science Center at San Antonio Objectives Cardiopulmonary Resuscitation Ana Hernandez Marin, MD, PL-6 Pediatric Critical Care Fellow Grand Rounds June 17, 2011 History of CPR • The Bible mentions early attempt at mouth to mouth "...And he went up, and lay upon the child, and put his mouth upon his mouth, and his eyes upon his eyes, and his hands upon his hands; and he stretched himself upon the child; and the flesh of the child waxed warm." Pulseless Cardiac Arrest • Early recognition of cardiac arrest is imperative – Effective CPR and advanced life support can optimize potential to restore life – Lack of recognition can result in death or neurologic devastation. • Define cardiac arrest • Identify the 4 phases of cardiac arrest • Review of current evidence and practice in post cardiac arrest care Pulseless Cardiac Arrest • Cessation of cardiac mechanical activity – Absence of palpable central pulse – Unresponsiveness – Apnea The Pulse Check • Feel for a pulse – May take up to 10 seconds – Brachial pulse in an infant – Carotid or femoral in child 1 Pediatrics Grand Rounds 17 June 2011 University of Texas Health Science Center at San Antonio The Pulse Check Causes of Cardiac Arrest • Problematic in infants and children – Palpable pulse until systolic BP < 50 in adults – Neonates Blood Pressure in 60’s – Decrease in BP can lead to “non palpable” pulse earlier – Accessibility to a central pulse Phases of Cardiac Arrest 1) Prearrest 2) No-Flow (untreated cardiac arrest) 3) Low-Flow (CPR) 4) Postresuscitation • Arrhythmogenic Ventricular Fibrillation • Rapid Ventricular Tachycardia Mechanical • Asphyxia • Ischemia • Metabolic • Pharmacologic Prearrest Phase * The greatest opportunity to impact patient survival by preventing pulseless cardiopulmonary arrest Interventions: Optimize community education regarding child safety Optimize patient monitoring and rapid emergency response Recognize and treat respiratory failure and shock to prevent cardiac arrest No-Flow Phase • Arrest Phase Interventions: Minimize interval to BLS and ALS Minimize interval to defibrillation, when indicated Low-Flow Phase • Resuscitation Interventions: “Push hard, push fast” Allow full-chest recoil Minimize interruptions in compressions Avoid Overventilation Consider adjuncts to improve vital organ perfusion during CPR Consider ECMO 2 Pediatrics Grand Rounds 17 June 2011 University of Texas Health Science Center at San Antonio Postresuscitation Phase Postresuscitation Phase Short-term rehabilitation Interventions: Longer-term rehabilitation (regenerate) Interventions: Optimize cardiac output and cerebral perfusion Treat arrhythmias, if indicated Avoid hyperglycemia, hyperthermia, hyperventilation Consider mild post-resuscitation systemic hypothermia Debrief to improve future responses to emergencies Early interventions with occupational and physical therapy Possible future role for stem cell transplantation5 Effectiveness of CPR in children • Out-of-hospital cardiac arrest – 6% of children survive7 – 8% of those who receive prehospital emergency response resuscitation survive. Effectiveness of CPR in children • In-hospital Resuscitation – 54% Return to Spontaneous Circulation (ROSC) – 27% overall survival to discharge8 • 2008 pediatric data National Registry of CardioPulmonary Resuscitation (NRCPR) – 33% survival pulseless arrests among 758 cases – 34% survival to discharge for patients with VF/pulseless VT – 38% survival for patients with pulseless electric activity – 24% survival for patients with asystole .Atkins DL, Everson-Stewart S, et al.. Circulation. 2009;119:1484-1491. Nadkarni VM, Larkin GL, Peberdy MA, et al JAMA. 2006;295:50-57 New CPR Guidelines Why CAB? • Previously recommended sequence Airway, Breathing, Circulation • 2010 American Heart Association Guidelines state Compressions, Airway, Breathing • During cardiac arrest high-quality CPR especially chest compressions are essential to generate blood flow to vital organs • All rescuers should be able to start chest compressions almost immediately • The CAB sequence for infants and children is recommended to simplify training – More victims will receive CPR. 3 Pediatrics Grand Rounds 17 June 2011 Combination of Ventilation and Compressions in Children • Asphyxia was induced by clamping the tracheal tube of piglets until cardiac arrest occurred. • Mean time to loss of aortic pulsations was 8.9 +/- 0.4 minutes. • Animals randomized to simulated bystander CPR or no CPR until simulated emergency medical service (EMS) arrival 8 minutes later. • After complete cardiac arrest, 24-hour survival was clearly superior in the group that received both cardiac compressions and rescue breathing, compared with either alone or no CPR. Berg, RA, Hilwig RW, Kern KB, et al. Crit Care Med. 1999 Circulation • Providing BLS with continuous effective chest compressions is best way to provide circulation during cardiac arrest. • CRITICAL ELEMENTS: – – – – – Push hard and push fast No compressions leads to no flow Minimize interruptions in chest compressions Allow full chest recoil to allow good venous return Avoid overcirculation can also prevent venous return University of Texas Health Science Center at San Antonio Combination of Ventilation and compressions in Children • Interventions at earlier point in ashyxial process : – When pulse was “no longer palpable” – Defined as systolic pressure less than 50 mmHg – Before complete loss of aortic pulsations • Results: – 24-hour survival was best when both chest compressions and rescue breathing provided. – Rescue breathing or chest compressions alone were individually better than no CPR at all. – Most animals had return of spontaneous circulation before EMS arrival. Berg RA, Hilwig RW, Kern KB, et al. Circulation. 2000 History • Closed chest cardiac massage was originally demonstrated in small dogs. • Investigators felt this cardiac massage might be helpful in children. • First patients to successfully be treated by cardiac massage were children. Circulation Mechanisms Circumferential vs. Focal Sternal Compressions • Mechanism of blood flow was direct compression of the heart between the sternum and the spine in children with compliant chest walls • Thoracic Pump Mechanism: Chest compressions increases intrathoracic pressure that creates a gradient between pulmonary vasculature, though the heart , and into the peripheral circulation. • Adult and animal models show circumferential CPR provides better CPR hemodynamics than point compressions • In small infants, its possible to encircle the chest with both hands and depress sternum with thumbs • “Two Thumb” compression method resulted in higher systolic and diastolic blood pressures 4 Pediatrics Grand Rounds 17 June 2011 Compression to Ventilation Ratio • Ideal Compression to Ventilation (C:V) ratios unknown • During CPR, ventilation needed is decreased because cardiac output only 10-25% that of sinus rhythm • Must balance benefits of positive pressure ventilation against negative consequences such as impeding circulation • Compression-only nor ventilation-only CPR can provide oxygen delivery to periphery for prolonged periods of CPR. Compression to Ventilation Ratio • optimal C:V ratio by – Lone healthcare providers is 30 compressions followed by 2 breathes – If 2 rescuers: 15 compressions followed by 2 breathes – For Lay rescuers: begin 30 compressions University of Texas Health Science Center at San Antonio Compression to Ventilation Ratio • The best ratio depends on – Compression rate – Tidal volume – Blood flow generated during compressions – Interrupted time of compressions Airway and Breathing • Goal of initial assisted ventilation – Adequate oxygen delivery to meet metabolic demands – Removal of carbon dioxide • Bag-Mask Ventilation cornerstone for effective ventilation – Tracheal intubation not necessarily required Endotracheal intubation Vs. Bag Mask Ventilation • JAMA 2000 – Randomized Control Trial – 830 patients <12 years of age – BVM (n=410) or BVM/intubation(n=420) – Survival BVM group 123/404 [30%]) & ETI group (110/416 [26%]) – odds ratio, 0.82; 95% confidence interval [CI], 0.61-1.11 Airway and Breathing • Less ventilation necessary for gas exchange because cardiac output and pulmonary blood flow are 10 – 25% of that during normal sinus rhythm • Overventilation is common – Compromise venous return and cardiac output – In association with interruptions in cardiac compressions can contribute to worse outcomes Gaushe M, Lewis RJ. JAMA 2000 5 Pediatrics Grand Rounds 17 June 2011 Airway and Breathing • Animal Models of sudden VF cardiac arrest – Pao2 and PaCo2 normal for 4 to 8 minutes during chest compressions without rescue breathing – outcomes as good with chest compressions alone as with chest compressions plus rescue breathing Why is rescue breathing not initially necessary in VF but important in asphyxia? • Asphyxia: respiratory arrest precede cardiac • • • • arrest Blood continues to flow to tissues Arterial and venous oxygen saturations decrease while carbon dioxide and lactate increase Continued pulmonary blood flow before cardiac arrest depletes the pulmonary oxygen reservoir. Asphyxia results in significant arterial hypoxemia and acidemia prior to resuscitation. Commotio Cordis Mechanically initiated VF due to relatively low-energy chest wall impact during a narrow window of repolarization University of Texas Health Science Center at San Antonio Why is rescue breathing not initially necessary in VF but important in asphyxia? • In acute fibrillatory cardiac arrest – Aortic oxygenation and carbon dioxide do not vary from prearrest state because there is no blood flow, aortic oxygen consumption is minimal. – When chest compressions are started, blood flowing from aorta to the coronary and cerebral circulations provides adequate oxygen delivery at an acceptable pH. – Myocardial oxygen delivery is limited by blood flow rather than oxygen content – Lungs serve as reservoir for oxygen in low flow CPR Pediatric Ventricular Fibrillation • Uncommon but not rare • 19% - 24 % initial rhythm in out-of-hospital cardiac arrest • More likely in Tricyclic antidepressant overdose, cardiomyopathy, post cardiac surgery and prolonged QT syndromes Ventricular Fibrillation • VF/ VT occur in 27% of in-hospital cardiac arrests • “Good” cardiac rhythm due to better outcomes • Survival to discharge is more common among children with initial shockable (VT/VF) rhythms. • But if VT/VF was a subsequent rhythm to PEA or asystole worse outcomes 6 Pediatrics Grand Rounds 17 June 2011 University of Texas Health Science Center at San Antonio Defibrillation Defibrillation Dose • Definition = Termination of ventricular Fibrillation • Defibrillation is necessary to successfully resuscitate from VF cardiac arrest • The goal is to return of an organized electrical rhythm with a pulse. • Early recognition is of VF is imperative to treat successfully. • 1970’s, initial defibrillation dose 200 Joules for all children. • Animal data >10 J/kg demonstrated histopathological myocardial damage. • Animal studies: 0.5-10 Joules/kg was adequate for defibrillation in various species. Defibrillation Dose Defibrillation for Prolonged VF • • • • • • • Retrospective Study 71 transthoracic defibrillations attempts 27 children evaluated Age: 3 days to 15 years 57:71 shocks were within 10 J of 2Joules/kg 91% (52:57) affective at terminating VF12 Therefore subsequent usage suggests 2J/kg effective for short duration, in hospital defibrillation • Animal studies: after 7 minutes of untreated VF in piglets (4-24kg) suggests 2 J/kg unsuccessful at terminating fibrillation in all 24 attempts • Small clinical study: Tucson – 11 children received 14 shocks (2 J/kg +/-10J) – 7:14 (50%) terminated out-of-hospital prolonged VF – (p<.01) Kanter RK, Boeing NM, Hannan WP, et al. Pediatrics 1992. Defibrillation for Prolonged VF • Lack of shock delivery of pediatric VF is 100% lethal • Adult defibrillation doses better than no defibrillation doses • Case Report: – 3 y/o in VF – Biphasic shock (9 J/kg) – Survived without adverse effects – No elevation in CK or cardiac troponin I Intraosseous Vascular Access • • • • Provides access to a noncollapsible marrow venous plexus Serves as rapid, safe, and reliable route Can be achieved in 30-60 seconds Inserted into anterior tibial bone marrow – Alternate sites: • Distal femur • Medial malleolus • Anterior superior iliac spine • Distal tibia • Older children: distal radius and distal ulna 7 Pediatrics Grand Rounds 17 June 2011 Intraosseous Vascular Access • Used for fluids, resuscitation drugs, catecholamine infusions and blood products. • May also obtain blood specimens for chemistry, blood gas analysis, blood typing, and cross matching. • Drugs levels and drug onset of action are comparable to vascular administration via central venous lines. Endotracheal Drug Administration • Less common since IO access • “LEAN” Drugs given endotracheally – Lidocaine – Epinephrine – Atropine – Naloxone University of Texas Health Science Center at San Antonio Intraosseous Vascular Access Complications: Reported in <1% of patients ex: tibial fractures lower extremity compartment syndrome severe extravasation of drugs osteomyelitis Animal Models: bone marrow emboli Endotracheal Drug Administration • Absorption of drugs into circulation depends – Dispersion over respiratory mucosa • Drugs remain as droplets in ETT – Pulmonary blood flow • Poor chest compressions limit pulmonary blood flow – Matching of ventilation to perfusion • Calcium and Sodium Bicarbonate not recommended via ET • Pulmonary edema, pneumonitis, and airway disease – irritating to airways and lung parenchyma Vasopressors • Epinephrine: α-adrenergic effect on vascular tone important during CPR – Increases systemic vascular resistance – Increases diastolic blood pressure – Increases likelihood of Return of Spontaneous Circulation (ROSC) – Can increase cerebral blood flow due peripheral vasoconstriction and directs blood to cerebral circulation Vasopressors • Epinephrine: β-adrenergic effects – Increase myocardial contractility – Increases heart rate – Relaxes smooth muscle in the skeletal muscle vascular bed and bronchi 8 Pediatrics Grand Rounds 17 June 2011 Calcium • Hypocalcemia is common in pediatric cardiac arrest. • Recommended during cardiac arrest due to: – Hypocalcemia – Hyperkalemia – Hypermagnesemia – Calcium-channel blocker overdose Commonly used in post-cardiac surgery cardiac arrest. Buffer Solutions • Sodium bicarbonate indicated: – Tricyclic antidepressants overdose – Hyperkalemia – Hypermagnesemia – Sodium-channel-blocker poisoning Antiarrhythmic • Should not delay shock in VF • If electrical defibrillation unsuccessful must give medications to increase effectiveness of shock: 1. Epinephrine 2. Amiodarone or Lidocaine University of Texas Health Science Center at San Antonio Buffer Solutions • Lactic acidosis results from inadequate organ blood flow and poor oxygenation. • Acidosis: – Depresses myocardial function – Reduces vascular resistance – Inhibits defibrillation • Sodium Bicarbonate not routinely used in cardiac arrest – Adult clinical studies and severe metabolic acidosis did not demonstrate beneficial effects. Buffer Solutions • H+ + HCO2- -> CO2 and H2O • Problems: – Must have ventilation to clear CO2 otherwise may counterbalance the buffer solution. – Hypernatremia – Hyperosmolarity – Metabolic alkalosis • Decreases calcium and potassium concentrations • Shifts oxyhemoglobin curve to the left Antiarrhythmics • Lidocaine: traditionally recommended in shock resistant VF in children and adults • Amiodarone: – Prospectively proven to improve survival in shockresistant VF when compared to placebo in adults. – Higher survival to admission for out-of-hospital shock resistant VF when compared to Lidocaine. • Amiodarone is the preferred antiarrhythmic agent for children. 9 Pediatrics Grand Rounds 17 June 2011 University of Texas Health Science Center at San Antonio Hypothermia Postresuscitation Interventions • Temperature Management • Blood Pressure Management • Glucose Control • • Randomized, Controlled Trial Inclusion criteria: – Patients >18 years old – Persistently comatose after successful resuscitation from non-traumatic VF • 77 patients randomized – hypothermia 33○C within 2 hours of ROSC and maintained for 12 hours – Normothermia • Results – 21/43 (49%) hypothermia group survived and had good outcome – 9/34 (26%) normothermic group survived and had good outcome – P-value=0.046, CI 0.58-0.95 • Conclusion= Moderate hypothermia improves outcomes in patients with coma after resuscitation from out-of-hospital arrest Bernard SA, Gray TW, Buist MD, Jones BM, et al. New England Journal of Medicine. 2002 Hypothermia • Multicenter trial • Inclusion criteria: – Patients >18 years old – Persistently comatose after successful resuscitation from nontraumatic VF • Goal Temperature 32 -34○ C for the first 24 hours postarrest • Measurement: 6 month survival with good neurological outcomes • Results: – 75/136 (55%) hypothermic group – 54/137 (39%) normothermic group • Mortality at 6 months: 41% in hypothermic vs. 55% in normothermic • Statistics: RR 1.40; 95% Confidence Interval 1.08 to 1.81 New England Journal of Medicine. 2002 Blood Pressure Management • Animal Models: – Brief, induced hypertension following resuscitation results in improved neurologic outcomes compared to normotension. • Human Studies – Retrospective • Postresuscitative hypertension associated with better neurologic outcome17 *Reasonable to aggressively treat and prevent hypotension. Behringer W, Kittler H, Sterz F, et al. Ann Intern Med 1998. Blood Pressure Management • Minimize blood pressure variability post cardiac arrest resuscitation. – 55% adults who survived out-of-hospital cardiac arrest required vasoactive infusions for hypotension. – Impaired autoregulation of cerebral blood flow • May not maintain cerebral perfusion pressure if hypotensive • May not be able to protect the brain for acute increases blood flow if hypertensive Laurent I, Monchi M, Chiche JD, et al. J Am Coll Cardiol 2002;. Glucose Control • Historical cohort observational study of all patients admitted to hospital with a spontaneous circulation after OHCA due to a cardiac cause in four different regions in Norway 1995-1999. • The in-hospital factors associated with survival were15: – no seizures – base excess > 3.5 mmol – body temperature <= 37.8○C – serum glucose < 190mg/dL 24 h after admittance Langhelle A, Tyvold SS, Lexow K, Hapnes SA, Sunde K, Steen PA Resuscitation. 2003;56:247-63. 10 Pediatrics Grand Rounds 17 June 2011 University of Texas Health Science Center at San Antonio Glucose Control • Meta-Analysis evaluating benefits and risks of tight glucose control vs. usual care in critically ill adult patients. • Data: MEDLINE, the Cochrane Library • Twenty-nine randomized controlled trials totaling 8432 patients. • Hospital mortality did not differ between tight glucose control and usual care overall 21.6% vs. 23.3%; RR, 0.93; 95% CI, 0.85-1.03 Postresuscitation outcomes • The most important post resuscitation outcome are survival with favorable neurologic outcome and acceptable quality of life. • Barriers to neurologic assessment – Changing developmental context – Little is known about predictive value of diagnostic studies – CT: not sensitive in predicting early neurologic injury • MRI with diffusion weighting is valuable for hypoxic-ischemia in subacute and recovery phases. • Biomarkers: enolase and S100b highly sensitive and specific for poor neurologic outcomes Wiener RS, Wiener DC, Larson RJ JAMA 2008 Conclusions • Pediatric cardiac arrest and CPR outcomes are improving. • Better understanding of pathophysiology events revolving cardiac arrest. • Focus on strategizing therapies at specific phases of cardiac arrest. • Clinical trials are necessary for appropriate evidence based recommendations for treatment of pediatric cardiac arrest. Review • • • • Quality CPR Definition of Cardiac arrest Phases of Cardiac Arrest Resuscitation guidelines Post resuscitation care strategies References PUSH HARD 1. PUSH FAST 2. 3. MINIMIZE INTERRUPTIONS 4. 5. 6. 7. ALLOW FULLCHEST RECOIL 8. 9. 10. and DON’T OVERVENTILATE 11. 12. Nichols, DG . Roger’s Textbook of Pediatric Intensive Care. Fourth Edition. Philadelphia, PA: Lipponcott Williams & Wilkins , 2008. Kyriacou DN, Arcinue EL, Peek C, Kraus JF. Effect of immediate resuscitation on children with submersion injury. Pediatrics. 1994;94(pt 1): 137-142. Berg MD, Schexnaydar SM, et al. 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science. Ciculation. 210;122:S862-S875. Donoghue AJ, Nadkarnu V, Berg RA, Osmond MH, Wells G, Nesbitt L, Stiell IG. Out-of-hospital pediatric cardiac arrest: an epidemiologic review and assessment of current knowledge. Ann Emerg Med. 2005;46:512-522. Wang T, Tang W, Sun S, Xu T, Wang H, Guan J, Huang Z, Weil MH. Intravenous infusion of bone marrow mesenchymal stem cells improves brain function after resuscitation from cardiac arrest. Crit Care Med. 2008 Nov;36(11 Suppl):S486-91. Kouwenhoven, WB, Jude JR, Knickerbocker GG. Closed-chest cardiac massage. JAMA 1960; 173:1064-7. Atkins DL, Everson-Stewart S, et al. Epidemiology and outcomes from out-of-hospital cardiac arrst in children: The resuscitation outcomes consortium Epistry-cardiac arrest. Circulation. 2009;119:1484-1491. Nadkarni VM, Larkin GL, Peberdy MA, et al. First documented rhythm and clinical outcome from in-hospital cardiac arrest among children and adults. JAMA. 2006;295:50-57. Berg, RA, Hilwig RW, Kern KB, et al. Simulated mouth-to-mouth ventilation and chest compressions (bystander cardiopulmonary resuscitation) improves outcome in a swine model if prehospital pediatric asphyxial cardiac arrest. Crit Care Med. 1999 Sep;27(9):1893-9 . Berg RA, Hilwig RW, Kern KB, et al. Bystander chest compressions and assisted ventilation independently improve outcome from piglet asphyxial pulseless “cardiac arrest”. Circulation. 2000;101:1743-1748. Gaushe M, Lewis RJ. Out-of-hospital endotracheal intubation. JAMA 2000; 283:2790-2 Kanter RK, Boeing NM, Hannan WP, et al. Excess morbidity associated with interhospital transfer. Pediatrics 1992;90: 893-8. 11 Pediatrics Grand Rounds 17 June 2011 University of Texas Health Science Center at San Antonio References 13. Bernard SA, Gray TW, Buist MD, Jones BM, Silvester W, Gutteridge G, Smith K. Treatment of comatose survivors of out-ofhospital cardiac arrest with induced hypothermia. New England Journal of Medicine. 2002 Feb 21;346(8):557-63. 14. Hypothermia after Cardiac Arrest Study Group. Mild therapeutic hypothermia to improve the neurologic outcome after cardiac arrest. New England Journal of Medicine. 2002 Feb 21;346(8):549-56. 15. Langhelle A, Tyvold SS, Lexow K, Hapnes SA, Sunde K, Steen PA . In Hospital factors associated with improved outcome after out-of-hospital cardiac arrest (OHCA). A comparison between four regions in Norway. Resuscitation. 2003;56:247-63 . 16. Laurent I, Monchi M, Chiche JD, et al. Reversible myocardial dysfunction in survivors of out-of-hospital cardiac arrest. J Am Coll Cardiol 2002;240;2110-16. 17. Behringer W, Kittler H, Sterz F, et al. Cumulative eoinephrine dose during cardiopulmonary resuscitation and neurologic outcome. Ann Intern Med 1998;129;450-6. 18. Langhelle A, Tyvold SS, Lexow K, Hapnes SA, Sunde K, Steen PA . Benefits and Risks of Tight Glucose Control in Critically Ill AdultsA Meta-analysis. Resuscitation. 2003;56:247-63 12