| Admissions | Accreditation | Booksellers | Catalog | Colleges | Contact Us | Continents/States/Districts | Contracts | Examinations | Forms | Grants | Hostels | Honorary Doctorate degree | Instructors | Lecture | Librarians | Membership | Professional Examinations | Programs | Recommendations | Research Grants | Researchers | Students login | Schools | Search | Seminar | Study Center/Centre | Thesis | Universities | Work counseling |
|
Advanced cardiac life support (ACLS) describes the treatment of cardiac arrest. ACLS may only be provided by trained experts, as it includes advanced ECG diagnostics, procedural skills, and use of medications. It builds upon basic life support, or CPR, and the use of automated external defibrillators (AEDs). Both these can be used by trained members of the public.
Throughout ACLS, it is critical to continue chest compression with minimal interruptions. ACLS survey is often done by many team members, and should be on an ongoing basis throughout ACLS response. Airway Is the airway open? Does the patient need an advanced airway? Breathing Is oxygenation and ventilation sufficient? If used, is the airway device properly placed and monitored? Are CO2 and O2 sats being monitored? Circulation What is the current cardiac rhythm? Is IV/IO access obtained? Does the patient need fluids or medications? Differential Diagnosis Why did arrest occur? Are there any other factors? Can we reverse the cause(s)? 7 H's and 6 T's: pnemonic for mechanisms * hypoxia * hypovolemia * hyperkalemia * hypokalemia * hypoglycemia * hypothermia * hydrogen ions (acidosis) * thrombosis (MI) * tension pneumothorax * tamponade * toxins/therapeutics * thromboembolism * trauma Heart conditions that can lead to sudden cardiac arrest More often, a life-threatening arrhythmia develops in a person with a pre-existing heart condition, such as: * Coronary artery disease. Most cases of sudden cardiac arrest occur in people who have coronary artery disease. In coronary artery disease, your arteries become clogged with cholesterol and other deposits, reducing blood flow to your heart. This can make it harder for your heart to conduct electrical impulses smoothly. * Heart attack. If a heart attack occurs, often as a result of severe coronary artery disease, it can trigger ventricular fibrillation and sudden cardiac arrest. In addition, a heart attack can leave behind areas of scar tissue. Electrical short circuits around the scar tissue can lead to abnormalities in your heart rhythm. * Enlarged heart (cardiomyopathy). This occurs primarily when your heart's muscular walls stretch and enlarge or thicken. In both cases, your heart's muscle is abnormal, a condition that often leads to heart tissue damage and potential arrhythmias. * Valvular heart disease. Leaking or narrowing of your heart valves can lead to stretching or thickening of your heart muscle, or both. When the chambers become enlarged or weakened because of stress caused by a tight or leaking valve, there's an increased risk of developing arrhythmia. * Congenital heart disease. When sudden cardiac arrest occurs in children or adolescents, it may be due to a heart condition that was present at birth (congenital heart disease). Even adults who've had corrective surgery for a congenital heart defect still have a higher risk of sudden cardiac arrest. * Electrical problems in the heart. In some people, the problem is in the heart's electrical system itself, instead of a problem with the heart muscle or valves. These are called primary heart rhythm abnormalities and include conditions such as Brugada's syndrome and long QT syndrome. Procedures and Medications Used There are many procedures that may be required during ACLS. These normally include insertion of intravenous (IV) lines and placement of various airway devices. Commonly used ACLS drugs, such as epinephrine, atropine and amiodarone, are then administered. * airway devices * vascular access and fluids * medications * monitoring * defibrillation * other Airway Devices Vascular Access and Fluids Vascular access is a priority during ACLS, allowing medications and fluids to be rapidly given. Options include: * peripheral venous access * intra-osseous access * central line access: usually unnecessary, and may cause many complications during recuscitation * endotraceal access: not preferred. Doses are unknown, buy are typically 2-2.5 x the IV dose. o may given epinephrine, vasopressin, atropine, lidocaine, naloxone. When Medications Medication administration is of secondary importance. While vasopressors do appear to assist with spontaneous return of circulation, they have not been shown to improve survial to hospital discharge (ref). When medications are given intravenously, give drug, follow by 20ml fluid bolus, and elevate limb for 102-0 seconds. A drug typically takes 1-2 minutes to reach the central circulation, or once cycle of CPR. Vasopressors increase cardiac output and blood pressure. Epinephrine hydrochloride is a sympathetic hormone. It is used during recusitation for its vasoconstrictive (alpha-adrenergic) capacities, increasing blood flow to the brain and heart. High-dose epinephrine does not appear to improve oucomes. The dose used is 1 mg IV/IO, given every 3-5 minutes during cardiac arrest and 2-10 µg/min infusion for symptomatic bradycardia. Vasopressin is a nonadrenergic peripheral vasoconstrictor. Its use does not improve outcomes, vs epinehrine. It may be given once during recusitation at a dose of 40 U IV/IO. Atropine is an ancholinergic medication, given during symptomicatic bradycardia or for slow PEA/asystole. The dose is 0.5 mg IV/IO for bradycardia and 1 mg IV/IO, repeated every 3-5 minutes, up to a maximum of three doses. Amiodarone is an atiarrhythmic drug, acting on sodium, potassium, and calcium channels, and with alpha- and beta-adrenergic blocking capacity. It comes with many substantial side effects, and should be used only in life-threatening situations by people well-versed in its use. Dose is 300 mg IV/IO once, then additional 150 mg IV/IO once after 3-5 minutes. Lidocaine is a sodium channel blocker. Amiodarone is preferred. The dose of lidocaine is 1-1.5 mg/kg IV/IO once, then 0.5-0.75 mg/kg IV/IO every 5-10 minutes, to a maximum of 3 mg/kg Magnesium sulfate may be used to stop or prevent torsades des pointes with prolonged QT interval. The loading dose for magnesium is 1-2g, diluted in 10 ml d5W, given IV/IO push over 5-20 minutes. Magnesium may also be helpful if serum magnesium is low, as can occur in alcoholics or other states of malnutrution. Dopamine hydrochloride is an alpha-adrenergic and beta-adrenergic agonist, to be used as an infusion in the treatment of symptomatic bradycardia. The dose is 2-10 µg/kg/min, titrated for patient response. It can be added to epinephrine or used alone. Adenosine is useful for medically treating stable, narrow-complex SVT due to rentry of the AV node or SA node. It should not be used in atrial fibrillation, atrial flutter, or VT, or with second- or third-degree heart block. Initial dose is 6 mg, given rapidly, followed by NS bolus and elevation of extremity. Second and third doses of 12 mg may be given in 1-2 minutes. Monitoring Defibrillation After the first shock, immediately resume CPR, givng 5 cycles. Other chest tube Effective Team Functioning Clinical Scenarios Always assess, then reassess the patient on an ongoing basis. * respiratory arrest * pulseless VT and VF * pulseless electrical activity and asystole * acute coronary syndromes * bradycardia * tachycardia * stroke Respiratory Arrest In respiratory arrest, a pulse is present, though breathing is absent or ineffective. Perform BLS. Give one breath every 5-6 seconds, or 10-12 per minute. Check pulse (quickly) every two minutes. Airway Consider placement of airway devices: * oropharyngeal airway * nasopharyngeal airway * laryngeal mask airway * endotracheal tube * esophageal-tracheal Combitube suction as needed Increasing acuity: urgent emergent, crash Difficult airways: Supraglottic device * MOODS * mouth open Four cornerstones of airway management * bag-valve-mask * laryngoscopy and intubation * cricothyrotomy * supraglottic device Breathing monitor oxygen and provide supplemental oxygen as appropriate Confirm proper placement, secure, and reassess frequently. * Obtain IV/IO access * attach ECG leads * give fluids and medications as appropriate Pulseless Ventricular Tachycardia and Ventricular Fibrillation With sudden cardiac arrest, the most common initial rhythms are pulseless ventricular tachycardia (VT) and ventricular fibrillation (VF). VT will rapidly lead to VF, which will become asystole unless defibrillation is quickly given. Ventricular fibrillation is the chaotic contraction of the heart, leading to a lack of perfusion and loss of consciousness. It is rapidly fatal without intervention. AED Begin with the basic life support (BLS) primary survey: ABCD Perform high-quality CPR until an AED arrives. Early defibrillation is critical to increase chances of survival. Inside hospital Begin with CPR, giving oxygen as available, until ECG monitor and defibrillator arrives with a code team. If skills are sufficient, AED should not be used, as it leads to unnecessary delays. The team leader will coordinate efforts. Pause chest compressions only for ventilation without advanced airway, for rhythm checks, and for shock delivery. Newer defibrillators charge rapidly, under 10 seconds. If this is the case, compressions may be paused during charge. If the charge time is longer than 10 seconds, continue compressions until shock is ready. New guidelines suggest one shock, with voltage depending on type of defibrillator: * manual biphasic: device specific 120-200 J * monophasic: 360 J Warn others firmly that a shock is imminent, and ensure all providers are clear. Immediately begin 5 cycles of CPR (2 minutes) before stopping for rhythm check. If rhythm is shockable, give shock. Immediately begin 5 cycles of CPR When IV/IO access is obtained, give vasopressor: * epinephrine 1mg IV/IO, repeat every 3-5 minutes * vasopressin 40 U IV/IO, may be given once Immediately begin 5 cycles of CPR (2 minutes) before stopping for rhythm check. If rhythm is shockable, give shock. Immediately begin 5 cycles of CPR. Consider antiarrhythmics: * amiodarone * lidocaine * magnesium If the montor shows a non-shockable, orgainized rhythm, do a pulse check. If pulse is present, begin post-resuscitation care. Hypotermia will be addressed elsewhere. Once perfusing rhythm has started, consider providing an antiarrhythmic (i.e., amiodarone or lidocaine) for maintenance therapy. It is usual to choose the drug used during recuscitation. Pulseless Electrical Activity and Systole In pulseless electrical activity (PEA), the target of intervention is the cause, not the rhythm. With PEA, it is imparative to provide quality care and to work hard to identify reversible causes. Both PEA and asystole are treated the same. Inside hospital Begin with CPR, giving oxygen as available, until ECG monitor and defibrillator arrives with a code team. During rhythm and pulse check, if PEA or asystole are identified, resume CPR immediately. IV/IO access is a priority over advanced airway placement. Vasopressors should be given once IV/IO access is in place. This includes: * epinehprine 1 mg IV/IO, repeated every 3-5 minutes * vasopressin 40 U may be given once in place of a dose of epinephrine Consider atropine 1 mg IV/IO for asystole or slow PEA; repeat every 3-5 minutes, to a maximum of 3 doses. Do rhythm/pulse checks every 2 minutes after administration of a drug. * if a shockable rhythm is present, shock, according to the VT/VF algorithm * if pulse is present, begin post-recuscitative care * if no shockable rhythm is present, continue CPR and vasopressor/atropine administration. Consider H's and T's, as above. Obtain a 12-lead ECG, which can provide clues as to the cause. With systole, ensure equipment is not responsible for the flat line, and that the rhythm is not fine VF. Recuscitation should be avoided in victims with * DNAR status * living will * rigor mortis * dangerous circumstances Acute Coronary Syndromes Bradycardia There are many causes of bradycardia, including sinus bradycardia and heart blocks. Symptomatic b Identification of a bradycardia should lead to primary survey of the ABC's, intervening as necessary. Oxygen is recommended. Monitor ECG, blood pressure, and oxygen saturation. Decision to treat depend on perfusion; if adequate, monitoring is sufficient. If perfusion is poor, however, treatment should be instituted. If type II, second-degree or third degree heart block is present, prepare immediately for transcutaneous pacing. Consider atropine 0.5 mg IV while waiting, repeating up to a maximum of 3 mg. Consider epinephrine (2-10 ug/min) or dopamine (2-10 ug/kg/min) infusion while waiting. Transcutaneous pacing may be painful and will require procedural sedation, potentially further compromising hemodynamics. However, in unstable patients, proceed immediately. Treat with TCP with the goal of improving clinical symptoms. If acute coronary syndrome is present, maintain pacing at the lowest current required. Tachycardia Tachycardia can be caused by a number of conditions. A key question is whether the patient has a pulse; if not, proceed with BLS. If pulses are present, determine whether patient is stable or unstable, and provide treatment accordingly. Unstable tachycardia occurs when the rate is so fast (often above 150/min), or so uncoordinated, that cardiac output drops. This can lead to cardiac, cerebral, and renal ischemia, and to pulmonary edema. In the ill or frail, lower heart rates can lead to instability. Signs and symptoms can include: * chest pain * shortness of breath * altered, decreased, or loss of consciousness * weakness or fatigue * hypotension * ECG signs of ischemia * pulomary edema * poor peripheral perfusion It is important to determine whether signs and symptoms are due to tachycardia, or whether the tachycardia and signs and symptoms are due to another condition (e.g., myocardial infarction). In general, a rate between 100-130/min suggests an underlying process. Stroke Stopping Recuscitation Each patient case is unique, and while clinical rules are developed, the decision to stop CPR is a complex one. Except in specific circumstances, such as hypothermia or drug overdose, BLS or ACLS are very unlikely to be successful after 20 minutes. In hospital, the decision is based upon: * time to CPR and defibrillation * duration of ACLS efforts * condition prior to arrest * initial arrest rhythm and response to ACLS treatments Outside hospital, CPR should be continued until: * circulation and ventilation commence * care is transferred to senior health care professional * irreversible death is clear * the situation becomes too hazardous * the rescuer(s) become exhausted * valid DNR is identified lifesupportcpr.com/ www.acls.net/ www.myicucare.org www.muhealth.org crashingpatient.com www.cdemcurriculum.org www.merckmanuals.com www.thoracic.org http://www.sharinginhealth.ca/treatments/ACLS.html |