***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    ***EXAMPLES*** 
    Input: Introduction Mild induced hypothermia ( MIH ) is indicated for comatose survivors of sudden cardiac arrest ( SCA ) to improve clinical outcome . In this study , we compared the efficacy of two different cooling devices for temperature management in SCA survivors . Methods Between April 2008 and August 2009 , 80 patients after survived in-hospital ( IHCA ) and out-of-hospital cardiac arrest ( OHCA ) were included in this prospect i ve , r and omized , single center study . Hypothermia was induced after r and omization by either invasive Coolgard ® cooling or non-invasive A rct icSun ® surface cooling at 33.0 ° C core body temperature for 24 h followed by active rewarming . The primary endpoint was defined as the efficacy of both cooling systems , measured by neuron-specific enolase ( NSE ) levels as a surrogate parameter for brain damage . Secondary efficacy endpoints were the clinical and neurological outcome , time to start of cooling and reaching the target temperature , target temperature-maintenance and hypothermia-associated complications . Results NSE at 72 h did not differ significantly between the 2 groups with 16.5 ng/ml , interquartile range 11.8–46.5 in surface-cooled patients versus 19.0 ng/ml , interquartile range 11.0–42.0 in invasive-cooled patients , p = 0.99 . Neurological and clinical outcome was similar in both groups . Target temperature of 33.0 ° C was maintained more stable in the invasive group ( 33.0 versus 32.7 ° C , p < 0.001 ) . Bleeding complications were more frequent with invasive cooling ( n = 17 [ 43.6 % ] versus n = 7 [ 17.9 % ] ; p = 0.03 ) . Conclusion Invasive cooling has advantages with respect to temperature management over surface cooling ; however , did not result in different outcome as measured by NSE release in SCA survivors . Bleeding complications were more frequently encountered by invasive cooling The beneficial effect of epinephrine has been attributed to its alpha-adrenergic properties . The present study was design ed to compare the effects of epinephrine and methoxamine in witnessed cardiac arrests . Consecutive , witnessed cardiac-arrest victims presenting to the emergency room or from the inpatient population of our institution were enrolled in this study . Patients were r and omized to receive either epinephrine ( 2 mg bolus followed by 2 mg every 4 min ) or methoxamine ( 40 mg bolus followed after 4 min by 40 mg ) in a blind design . Patients were followed prospect ively for survival and neurologic outcome . A total of 199 patients were r and omized into the study , but 54 had to be retrospectively dropped from analysis for failure to comply with the study protocol . Of the 145 patients remaining , 77 received methoxamine ( M ) and 68 epinephrine ( E ) . There was no difference in rate of successful resuscitation ( 42 % versus 53 % , M versus E , respectively ) , or in neurologic outcome as measured by the Glasgow-Pittsburgh Coma Score ( GPCS ) . This study failed to demonstrate any difference in the rate of initial resuscitation , survival to discharge from the hospital , or neurologic status with methoxamine as opposed to epinephrine in the setting of cardiac arrest IMPORTANCE A strategy using mechanical chest compressions might improve the poor outcome in out-of-hospital cardiac arrest , but such a strategy has not been tested in large clinical trials . OBJECTIVE To determine whether administering mechanical chest compressions with defibrillation during ongoing compressions ( mechanical CPR ) , compared with manual cardiopulmonary resuscitation ( manual CPR ) , according to guidelines , would improve 4-hour survival . DESIGN , SETTING , AND PARTICIPANTS Multicenter r and omized clinical trial of 2589 patients with out-of-hospital cardiac arrest conducted between January 2008 and February 2013 in 4 Swedish , 1 British , and 1 Dutch ambulance services and their referring hospitals . Duration of follow-up was 6 months . INTERVENTIONS Patients were r and omized to receive either mechanical chest compressions ( LUCAS Chest Compression System , Physio-Control/Jolife AB ) combined with defibrillation during ongoing compressions ( n = 1300 ) or to manual CPR according to guidelines ( n = 1289 ) . MAIN OUTCOMES AND MEASURES Four-hour survival , with secondary end points of survival up to 6 months with good neurological outcome using the Cerebral Performance Category ( CPC ) score . A CPC score of 1 or 2 was classified as a good outcome . RESULTS Four-hour survival was achieved in 307 patients ( 23.6 % ) with mechanical CPR and 305 ( 23.7 % ) with manual CPR ( risk difference , -0.05 % ; 95 % CI , -3.3 % to 3.2 % ; P > .99 ) . Survival with a CPC score of 1 or 2 occurred in 98 ( 7.5 % ) vs 82 ( 6.4 % ) ( risk difference , 1.18 % ; 95 % CI , -0.78 % to 3.1 % ) at intensive care unit discharge , in 108 ( 8.3 % ) vs 100 ( 7.8 % ) ( risk difference , 0.55 % ; 95 % CI , -1.5 % to 2.6 % ) at hospital discharge , in 105 ( 8.1 % ) vs 94 ( 7.3 % ) ( risk difference , 0.78 % ; 95 % CI , -1.3 % to 2.8 % ) at 1 month , and in 110 ( 8.5 % ) vs 98 ( 7.6 % ) ( risk difference , 0.86 % ; 95 % CI , -1.2 % to 3.0 % ) at 6 months with mechanical CPR and manual CPR , respectively . Among patients surviving at 6 months , 99 % in the mechanical CPR group and 94 % in the manual CPR group had CPC scores of 1 or 2 . CONCLUSIONS AND RELEVANCE Among adults with out-of-hospital cardiac arrest , there was no significant difference in 4-hour survival between patients treated with the mechanical CPR algorithm or those treated with guideline -adherent manual CPR . The vast majority of survivors in both groups had good neurological outcomes by 6 months . In clinical practice , mechanical CPR using the presented algorithm did not result in improved effectiveness compared with manual CPR . TRIAL REGISTRATION clinical trials.gov Identifier : NCT00609778 BACKGROUND Out-of-hospital cardiac arrest ( OHCA ) remains a leading cause of death and a 2010 meta- analysis concluded that outcomes have not improved over several decades . However , guidelines have changed to emphasize CPR quality , minimization of interruptions , and st and ardized post-resuscitation care . We sought to evaluate whether OHCA outcomes have improved over time among agencies participating in the Resuscitation Outcomes Consortium ( ROC ) cardiac arrest registry ( Epistry ) and r and omized clinical trials ( RCTs ) . METHODS Observational cohort study of 47,148 EMS-treated OHCA cases in Epistry from 139 EMS agencies at 10 ROC sites that participated in at least one RCT between 1/1/2006 and 12/31/2010 . We review ed patient , scene , event characteristics , and outcomes of EMS-treated OHCA over time , including subgroups with initial rhythm of pulseless ventricular tachycardia or ventricular fibrillation ( VT/VF ) . RESULTS Mean response interval , median age and male proportion remained similar over time . Unadjusted survival to discharge increased between 2006 and 2010 for treated OHCA ( from 8.2 % to 10.4 % ) , as well as for subgroups of VT/VF ( 21.4 % to 29.3 % ) and byst and er witnessed VT/VF ( 23.5 % to 30.3 % ) . Compared with 2006 , adjusted survival to discharge was significantly higher in 2010 for treated cases ( OR = 1.72 ; 95 % CI 1.53 , 1.94 ) , VT/VF cases ( OR = 1.69 ; 95 % CI 1.45 , 1.98 ) and byst and er witnessed VT/VF cases ( OR = 1.65 ; 95 % CI 1.36 , 2.00 ) . Tests for trend in each subgroup were significant ( p < 0.001 ) . CONCLUSIONS ROC-wide survival increased significantly between 2006 and 2010 . Additional research efforts are warranted to identify specific factors associated with this improvement Background — Although delayed hospital cooling has been demonstrated to improve outcome after cardiac arrest , in-field cooling started immediately after the return of spontaneous circulation may be more beneficial . The aims of the present pilot study were to assess the feasibility , safety , and effectiveness of in-field cooling . Methods and Results — We determined the effect on esophageal temperature , before hospital arrival , of infusing up to 2 L of 4 ° C normal saline as soon as possible after resuscitation from out-of-hospital cardiac arrest . A total of 125 such patients were r and omized to receive st and ard care with or without intravenous cooling .  Of the 63 patients r and omized to cooling , 49 ( 78 % ) received an infusion of 500 to 2000 mL of 4 ° C normal saline before hospital arrival . These 63 patients experienced a mean temperature decrease of 1.24±1 ° C with a hospital arrival temperature of 34.7 ° C , whereas the 62 patients not r and omized to cooling experienced a mean temperature increase of 0.10±0.94 ° C ( P<0.0001 ) with a hospital arrival temperature of 35.7 ° C . In-field cooling was not associated with adverse consequences in terms of blood pressure , heart rate , arterial oxygenation , evidence for pulmonary edema on initial chest x-ray , or rearrest . Secondary end points of awakening and discharged alive from hospital trended toward improvement in ventricular fibrillation patients r and omized to in-field cooling . Conclusions — These pilot data suggest that infusion of up to 2 L of 4 ° C normal saline in the field is feasible , safe , and effective in lowering temperature . We propose that the effect of this cooling method on neurological outcome after cardiac arrest be studied in larger numbers of patients , especially those whose initial rhythm is ventricular fibrillation Purpose Mild therapeutic hypothermia ( TH ) is recommended as soon as possible after the return of spontaneous circulation to improve outcomes after out-of-hospital cardiac arrest ( OHCA ) . Pre clinical data suggest that the benefit of TH could be increased if treatment is started during cardiac arrest . We aim ed to study the impact of intra-arrest therapeutic hypothermia ( IATH ) on neurological injury and inflammation following OHCA . Methods We conducted a 1:1 r and omized , multicenter study in three prehospital emergency medical services and four critical care units in France . OHCA patients , irrespective of the initial rhythm , received either an infusion of cold saline and external cooling during cardiac arrest ( IATH group ) or TH started after hospital admission ( hospital-cooling group ) . The primary endpoint was neuron-specific enolase ( NSE ) serum concentrations at 24 h. Secondary endpoints included IL-6 , IL-8 , and IL-10 concentrations , and clinical outcome . Results Of the 245 patients included , 123 were analyzed in the IATH group and 122 in the hospital-cooling group . IATH  decreased time to reach temperature ≤34 ° C by 75 min ( 95 % CI : 4 ; 269 ) . The rate of patients admitted alive to hospital was not different between groups [ IATH n = 41 ( 33 % ) vs. hospital cooling n = 36 ( 30 % ) ; p = 0.51 ] . Levels of NSE and inflammatory biomarkers were not different between groups [ median NSE at 24 h : IATH 96.7 μg/l ( IQR : 49.9–142.8 ) vs. hospital cooling 97.6 μg/l ( IQR : 74.3–142.4 ) , p = 0.64 ] . No difference in survival and cerebral performance were found at 1 month . Conclusions IATH did not affect biological markers of inflammation or brain damage or clinical outcome Background — Although biphasic , as compared with monophasic , waveform defibrillation for cardiac arrest is increasing in use and popularity , whether it is truly a more lifesaving waveform is unproven . Methods and Results — Consecutive adults with nontraumatic out-of-hospital ventricular fibrillation cardiac arrest were r and omly allocated to defibrillation according to the waveform from automated external defibrillators administered by prehospital medical providers . The primary event of interest was admission alive to the hospital . Secondary events included return of rhythm and circulation , survival , and neurological outcome . Providers were blinded to automated defibrillator waveform . Of 168 r and omized patients , 80 ( 48 % ) and 68 ( 40 % ) consistently received only monophasic or biphasic waveform shocks , respectively , throughout res 
    Output:
    
Important gaps in RCTs of cardiac arrest treatments exist , especially those examining in-hospital cardiac arrest , protocol improvement , postcardiac arrest care , and long-term or quality -of-life outcomes