***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 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background Prehospital resuscitation for patients with major trauma emphasizes a load- and -go principle . For traumatic cardiac arrest ( TCA ) patients , the administration of vasopressors remains under debate . This study evaluated the effectiveness of epinephrine in the prehospital setting for patients with TCA . Methods We conducted a retrospective cohort study using a prospect ively collected registry for out-of-hospital cardiac arrest in Taipei . Enrollees were ≥18 years of age with TCA . Patients with signs of obvious death like decapitation or rigor mortis were excluded . Patients were grouped according to prehospital administration , or lack thereof , of epinephrine . Outcomes were sustained ( ≥2 h ) recovery of spontaneous circulation ( ROSC ) and survival to discharge . A subgroup analysis was performed by stratified total prehospital time . Results From June 1 2010 to May 31 2013 , 514 cases were enrolled .  Epinephrine was administered in 43 ( 8.4 % ) cases . Among all patients , sustained ROSC and survival to discharge was 101 ( 19.6 % ) and 20 ( 3.9 % ) , respectively . The epinephrine group versus the non-epinephrine group had higher sustained ROSC ( 41.9 % vs. 17.6 % , p < 0.01 ) and survival to discharge ( 14.0 % vs. 3.0 % , p < 0.01 ) . The adjusted odds ratios ( ORs ) of epinephrine effect were 2.24 ( 95 % confidence interval ( CI ) 1.05 - 4.81 ) on sustained ROSC , and 2.94 ( 95 % CI 0.85 - 10.15 ) on survival to discharge . Subgroup analysis showed increased ORs of epinephrine effect on sustained ROSC with a longer prehospital time . Conclusion Among adult patients with TCA in an Asian metropolitan area , administration of epinephrine in the prehospital setting was associated with increased short-term survival , especially for those with a longer prehospital time Objective : To assess whether intermittent impedance of inspiratory gas exchange improves hemodynamic parameters , 48-hr survival , and neurologic outcome in a swine model of asphyxial cardiac arrest treated with active compression-decompression cardiopulmonary resuscitation . Design : Prospect i ve , r and omized , double-blind study . Setting : Laboratory investigation . Subjects : Thirty healthy L and race/Large-White piglets of both sexes , aged 10 to 15 wks , whose average weight was 19 ± 2 kg . Interventions : At approximately 7 mins following endotracheal tube clamping , ventricular fibrillation was induced and remained untreated for another 8 mins . Before initiation of cardiopulmonary resuscitation , animals were r and omly assigned to either receive active compression-decompression cardiopulmonary resuscitation plus a sham impedance threshold device ( control group , n = 15 ) , or active compression-decompression cardiopulmonary resuscitation plus an active impedance threshold device ( experimental group , n = 15 ) . Electrical defibrillation was attempted every 2 mins until return of spontaneous circulation or asystole . Measurements and Main Results : Return of spontaneous circulation was observed in six ( 40 % ) animals treated with the sham valve and 14 ( 93.3 % ) animals treated with the active valve ( p = .005 , odds ratio 21.0 , 95 % confidence interval 2.16–204.6 ) . Neuron-specific enolase and S-100 levels increased in the ensuing 4 hrs post resuscitation in both groups , but they were significantly elevated in animals treated with the sham valve ( p < .01 ) . At 48 hrs , neurologic alertness score was significantly better in animals treated with the active valve ( 79.1 ± 18.7 vs. 50 ± 10 , p < .05 ) and was strongly negatively correlated with 1- and 4-hr postresuscitation neuron-specific enolase ( r = −.86 , p < .001 and r = −.87 , p < .001 , respectively ) and S-100 ( r = −.77 , p < .001 and r = −0.8 , p = .001 ) values . Conclusions : In this model of asphyxial cardiac arrest , intermittent airway occlusion with the impedance threshold device during the decompression phase of active compression-decompression cardiopulmonary resuscitation significantly improved hemodynamic parameters , 24- and 48-hr survival , and neurologic outcome evaluated both with clinical and biochemical parameters ( neuron-specific enolase , S-100 ) Abstract While therapeutic hypothermia improves the outcomes of individuals in cardiac arrest , the hemodynamic responses and mechanisms which underlie hypothermia-induced cardioprotection are not fully understood . Therefore , we investigated the mechanism by which induced hypothermia preserves cardiac function and protects against mitochondrial damage following cardiac arrest . Cardiac arrest was induced in adult male Wistar rats by asphyxiation for 8.5 min . Following resuscitation , the animals were r and omly assigned to a hypothermia ( 32 ° C ) or normothermia ( 37 ° C ) group . Monitoring results showed that cardiac output at the fourth hour after resuscitation was significantly better in rats treated with hypothermia when compared to rats treated with normothermia ( P < 0.01 ) . Examinations by transmission electron microscopy showed that mitochondria in the left ventricle of rats in the hypothermia group were significantly less swollen compared to such mitochondria in the normothermia group ( P < 0.001 ) . Additionally , opening of mitochondrial permeability transition pores occurred less frequently in the hypothermic group . While complex I/III activity in the electron transport reaction was damaged after cardiac arrest and resuscitation , the degree of injury was ameliorated by hypothermia treatment ( P < 0.05 ) . The amount of STAT-3 phosphorylated at tyrosine 705 and its expression in mitochondria were significantly higher under hypothermia treatment compared to normothermia treatment . In vitro studies showed that inhibition STAT-3 activation abolished the  ability of hypothermia  to protect H9C2 cardiomyocytes against injury produced by simulated ischemia and reperfusion . Therapeutic hypothermia treatment can ameliorate cardiac dysfunction and help preserve both mitochondrial integrity and electron transport activity BACKGROUND Previous research has demonstrated significant relationships between peri-shock pause and survival to discharge from out-of-hospital shockable cardiac arrest ( OHCA ) . OBJECTIVE To determine the impact of peri-shock pause on survival from OHCA during the ROC PRIMED r and omized controlled trial . METHODS We included patients in the ROC PRIMED trial who suffered OHCA between June 2007 and November 2009 , presented with a shockable rhythm and had CPR process data for at least one shock . We used multivariable logistic regression to determine the association between peri-shock pause duration and survival to hospital discharge . RESULTS Among 2006 patients studied , the median ( IQR ) shock pause duration was : pre-shock pause 15s ( 8 , 22 ) ; post-shock pause 6s ( 4 , 9 ) ; and peri-shock pause 22.0 s ( 14 , 31 ) . After adjusting for Utstein predictors of survival as well as CPR quality measures , the odds of survival to hospital discharge were significantly higher for patients with pre-shock pause < 10s ( OR : 1.52 , 95 % CI : 1.09 , 2.11 ) and peri-shock pause < 20s ( OR : 1.82 , 95 % CI : 1.17 , 2.85 ) when compared to patients with pre-shock pause ≥ 20s and peri-shock pause ≥ 40s . Post-shock pause was not significantly associated with survival to hospital discharge . Results for neurologically intact survival ( Modified Rankin Score ≤ 3 ) were similar to our primary outcome . CONCLUSIONS In patients with cardiac arrest presenting in a shockable rhythm during the ROC PRIMED trial , shorter pre- and peri-shock pauses were significantly associated with higher odds of survival . Future cardiopulmonary education and technology should focus on minimizing all peri-shock pauses IMPORTANCE It is unclear whether advanced airway management such as endotracheal intubation or use of supraglottic airway devices in the prehospital setting improves outcomes following out-of-hospital cardiac arrest ( OHCA ) compared with conventional bag-valve-mask ventilation . OBJECTIVE To test the hypothesis that prehospital advanced airway management is associated with favorable outcome after adult OHCA . DESIGN , SETTING , AND PARTICIPANTS Prospect i ve , nationwide , population -based study ( All-Japan Utstein Registry ) involving 649,654 consecutive adult patients in Japan who had an OHCA and in whom resuscitation was attempted by emergency responders with subsequent transport to medical institutions from January 2005 through December 2010 . MAIN OUTCOME MEASURES Favorable neurological outcome 1 month after an OHCA , defined as cerebral performance category 1 or 2 . RESULTS Of the eligible 649,359 patients with OHCA , 367,837 ( 57 % ) underwent bag-valve-mask ventilation and 281,522 ( 43 % ) advanced airway management , including 41,972 ( 6 % ) with endotracheal intubation and 239,550 ( 37 % ) with use of supraglottic airways . In the full cohort , the advanced airway group incurred a lower rate of favorable neurological outcome compared with the bag-valve-mask group ( 1.1 % vs 2.9 % ; odds ratio [ OR ] , 0.38 ; 95 % CI , 0.36 - 0.39 ) . In multivariable logistic regression , advanced airway management had an OR for favorable neurological outcome of 0.38 ( 95 % CI , 0.37 - 0.40 ) after adjusting for age , sex , etiology of arrest , first documented rhythm , witnessed status , type of byst and er cardiopulmonary resuscitation , use of public access automated external defibrillator , epinephrine administration , and time intervals . Similarly , the odds of neurologically favorable survival were significantly lower both for endotracheal intubation ( adjusted OR , 0.41 ; 95 % CI , 0.37 - 0.45 ) and for supraglottic airways ( adjusted OR , 0.38 ; 95 % CI , 0.36 - 0.40 ) . In a propensity score-matched cohort ( 357,228 patients ) , the adjusted odds of neurologically favorable survival were significantly lower both for endotracheal intubation ( adjusted OR , 0.45 ; 95 % CI , 0.37 - 0.55 ) and for use of supraglottic airways ( adjusted OR , 0.36 ; 95 % CI , 0.33 - 0.39 ) . Both endotracheal intubation and use of supraglottic airways were similarly associated with decreased odds of neurologically favorable survival . CONCLUSION AND RELEVANCE Among adult patients with OHCA , any type of advanced airway management was independently associated with decreased odds of neurologically favorable survival compared with conventional bag-valve-mask ventilation OBJECT To examine the efficacy of a new method of cardiac resuscitation , active compression-decompression cardiopulmonary resuscitation ( ACD CPR ) , in prehospital cardiac arrest . DESIGN Prospect i ve , r and omized , controlled trial . SETTING Physician-manned Mobile Intensive Care Unit ( MICU ) of a university hospital , serving a population of 200,000 . PARTICIPANTS Adult patients with prehospital nontraumatic cardiac arrest treated by the MICU . INTERVENTIONS Patients were r and omized to st and ard chest compression according to American Heart Association ( AHA ) recommendations ( group 1 , 30 patients ) or to the new technique ( group 2 , 26 patients ) . ACD was performed by use of a h and -held suction device . In both groups , advanced life support was performed as recommended by the AHA . MEASUREMENTS AND MAIN RESULTS Rate of patients regaining a spontaneous circulation ( ROSC ) , hospital discharge rate , and mean carbon dioxide content during resuscitation were recorded . ROSC rates in groups 1 and 2 were 40 % and 38.5 % , respectively . Four patients ( 13.3 % ) in group 1 and three patients ( 11.5 % ) in group 2 were discharged ( group 1 v group 2 : n.s . ) . Anatomic conditions precluded the application of ACD CPR in 5 patients . The new technique was found to impose greater physical efforts than STD CPR . Capnography was performed in 23 patients ( mean value : STD CPR : 11.9 + /- 4.7 mmHg , ACD CPR : 13.7 + /- 4.9 mmHg [ n.s . ] ) . CONCLUSIONS ACD CPR did not improve , outcome and practical performance was complicated . Therefore , this technique should not be performed routinely , or without strict supervision in prehospital cardiac arrest Background —Active compression-decompression ( ACD ) CPR combined with an inspiratory imped 
    Output:
    
There was also no significant difference in survival or neurologic outcome at hospital discharge between active compression-decompression resuscitation or impedance threshold device and st and ard cardiopulmonary resuscitation .
The meta-regression indicated that this minimal effect might be modified by two important prognostic factors , that is , witnessed status and response time .
After adjustment of these two factors , impedance threshold device appeared to improve return of spontaneous circulation , which could be further augmented by advanced airway use .
Active compression-decompression resuscitation or impedance threshold device seemed not to improve return of spontaneous circulation in out-of-hospital cardiac arrest patients .
The meta-regression indicated two probable prognostic factors causing this minimal effect .