European Resuscitation Council Guidelines for Resuscitation ... - CPR

18 de 0ctubre de 2010 www.elsuapdetodos.com1236 J.P. Nolan et al. / Resuscitation 81 (2010) 1219–1276rescuers are well-trained and that if a circulatory adjunct is used, aprogram of continuous surveillance be in place to ensure that useof the adjunct does not adversely affect survival. Although manualchest compressions are often performed very poorly, 287–289 noadjunct has consistently been shown to be superior to conventionalmanual CPR.Impedance threshold device (ITD)The impedance threshold device (ITD) is a valve that limits airentry into the lungs during chest recoil between chest compressions;this decreases intrathoracic pressure and increases venousreturn to the heart. A recent meta-analysis demonstrated improvedROSC and short-term survival but no significant improvement ineither survival to discharge or neurologically intact survival to dischargeassociated with the use of an ITD in the management ofadult OHCA patients. 290 In the absence of data showing that the ITDincreases survival to hospital discharge, its routine use in cardiacarrest is not recommended.Lund University cardiac arrest system (LUCAS) CPRThe Lund University cardiac arrest system (LUCAS) is a gasdrivensternal compression device that incorporates a suction cupfor active decompression. Although animal studies showed thatLUCAS-CPR improves haemodynamic and short-term survival comparedwith standard CPR. 291,292 there are no published randomisedhuman studies comparing LUCAS-CPR with standard CPR.Load-distributing band CPR (AutoPulse)The load-distributing band (LDB) is a circumferential chest compressiondevice comprising a pneumatically actuated constrictingband and backboard. Although the use of LDB-CPR improveshaemodynamics, 293–295 results of clinical trials have been conflicting.Evidence from one multicentre randomised control trialin over 1000 adults documented no improvement in 4-h survivaland worse neurological outcome when LDB-CPR was usedby EMS providers for patients with primary out-of-hospital cardiacarrest. 296 A non-randomised human study reported increasedsurvival to discharge following OHCA. 297The current status of LUCAS and AutoPulseTwo large prospective randomised multicentre studies are currentlyunderway to evaluate the LDB (AutoPulse) and the LundUniversity Cardiac Arrest System (LUCAS). The results of thesestudies are awaited with interest. In hospital, mechanical deviceshave been used effectively to support patients undergoing primarycoronary intervention (PCI) 298,299 and CT scans 300 and also forprolonged resuscitation attempts (e.g., hypothermia, 301,302 poisoning,thrombolysis for pulmonary embolism, prolonged transportetc) where rescuer fatigue may impair the effectiveness of manualchest compression. In the prehospital environment where extricationof patients, resuscitation in confined spaces and movement ofpatients on a trolley often preclude effective manual chest compressions,mechanical devices may also have an important role.During transport to hospital, manual CPR is often performed poorly;mechanical CPR can maintain good quality CPR during an ambulancetransfer. 303,304 Mechanical devices also have the advantage ofallowing defibrillation without interruption in external chest compression.The role of mechanical devices in all situations requiresfurther evaluation.Peri-arrest arrhythmiasThe correct identification and treatment of arrhythmias in thecritically ill patient may prevent cardiac arrest from occurring orfrom reoccurring after successful initial resuscitation. These treatmentalgorithms should enable the non-specialist ALS provider totreat the patient effectively and safely in an emergency. If patientsare not acutely ill there may be several other treatment options,including the use of drugs (oral or parenteral) that will be lessfamiliar to the non-expert. In this situation there will be time toseek advice from cardiologists or other senior doctors with theappropriate expertise.The initial assessment and treatment of a patient with anarrhythmia should follow the ABCDE approach. Key elements inthis process include assessing for adverse signs; administration ofhigh flow oxygen; obtaining intravenous access, and establishingmonitoring (ECG, blood pressure, SpO 2 ). Whenever possible, recorda 12-lead ECG; this will help determine the precise rhythm, eitherbefore treatment or retrospectively. Correct any electrolyte abnormalities(e.g., K + ,Mg 2+ ,Ca 2+ ). Consider the cause and context ofarrhythmias when planning treatment.The assessment and treatment of all arrhythmias addresses twofactors: the condition of the patient (stable versus unstable), andthe nature of the arrhythmia. Anti-arrhythmic drugs are slower inonset and less reliable than electrical cardioversion in converting atachycardia to sinus rhythm; thus, drugs tend to be reserved for stablepatients without adverse signs, and electrical cardioversion isusually the preferred treatment for the unstable patient displayingadverse signs.Adverse signsThe presence or absence of adverse signs or symptoms will dictatethe appropriate treatment for most arrhythmias. The followingadverse factors indicate a patient who is unstable because of thearrhythmia.1. Shock – this is seen as pallor, sweating, cold and clammy extremities(increased sympathetic activity), impaired consciousness(reduced cerebral blood flow), and hypotension (e.g., systolicblood pressure