***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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    Input: OBJECTIVE : To test the hypothesis that limited paramedic advanced life support skills afford no advantage in survival from cardiac arrest when compared with non-paramedic ambulance crews equipped with defibrillators in an urban environment ; and to investigate whether separate response units delayed on scene times . METHODS : A prospect i ve , observational study was conducted over 17 consecutive months on all adult patients brought to the accident and emergency ( A&E ) department of Glasgow Royal Infirmary having suffered an out of hospital cardiac arrest of cardiac aetiology . The main interventions were byst and er cardiopulmonary resuscitation ( CPR ) and limited advance life support skills . MAIN OUTCOME MEASURES : Return of spontaneous circulation , survival to admission , and discharge . RESULTS : Of 240 patients brought to the A&E department , 19 had no clear record of whether a paramedic was or was not involved and so were excluded . There was no difference in survival between the two groups , although a trend to admission favoured non-paramedics . Paramedics spent much longer at the scene ( P < 0.0001 ) . Witnessed arrests ( P = 0.01 ) , early byst and er CPR ( P = 0.12 ) , shockable rhythms ( P = 0.003 ) , and defibrillation ( P < 0.0001 ) were associated with better survival . Intubation and at scene times were not associated with better survival . Delayed second response units did not prolong at scene times . CONCLUSIONS : The interventions of greatest benefit in out of hospital cardiac arrest are basic life support and defibrillation . Additional skills are of question able benefit and may detract from those of greatest benefit BACKGROUND Prehospital emergency medical services ( EMS ) play a major role in any trauma system . However , there is very little information regarding the role of prehospital emergency care in trauma . To investigate this issue , we compared the outcome of severely injured patients transported by paramedics ( EMS group )  with the outcome of those transported by friends , relatives , byst and ers , or police ( non-EMS group ) . DESIGN We compared 4856 EMS patients with 926 non-EMS patients . General linear model analysis was performed to test the hypothesis that hospital mortality is the same in EMS and non-EMS cases , controlling for the following confounding factors , which are not affected by mode of transportation : age , gender , mechanism of injury , cause of injury , Injury Severity Score ( ISS ) , and severe head injury . Crude , specific , and adjusted mortality rates and relative risks were also derived for the EMS and non-EMS groups . SETTING Large , urban , academic level I trauma center . PATIENTS All patients meeting the criteria for major trauma . RESULTS The two groups were similar with regard to mechanism of injury and the need for surgery or intensive care unit admission . The crude mortality rate was 9.3 % in the EMS group and 4.0 % in the non-EMS group ( relative risk , 2.32 ; P < .001 ) . After adjustment for ISS , the relative risk was 1.60 ( P = .002 ) . Subgroup analysis showed that among patients with ISS greater than 15 , those in the EMS group had a mortality rate twice that of those in the non-EMS group ( 28.8 % vs 14.1 % ) . After controlling for confounding factors , the adjusted mortality among patients with ISS greater than 15 was 28.2 % for the EMS group and 17.9 % for the non-EMS group ( P < .001 ) . CONCLUSIONS Patients with severe trauma transported by private means in this setting have better survival than those transported via the EMS system . Large prospect i ve studies are needed to identify the factors responsible for this difference OBJECTIVE Determine whether prehospital advanced life support ( ALS ) improves the survival of major trauma patients and whether it is associated with longer on-scene times . METHODS A 36-month retrospective study of all major trauma patients who received either prehospital bag-valve-mask ( BVM ) or endotracheal intubation ( ETI ) and were transported by paramedics to our Level I trauma center . Logistic regression analysis determined the association of prehospital ALS with patient survival . RESULTS Of 9,451 major trauma patients , 496 ( 5.3 % ) had either BVM or ETI . Eighty-one percent received BVM , with a mean Injury Severity Score of 29 and a mortality rate of 67 % ; 93 patients ( 19 % ) underwent successful ETI , with a mean Injury Severity Score of 35 and a mortality rate of 93 % . Adjusted survival for patients who had BVM was 5.3 times more likely than for patients who had ETI ( 95 % confidence interval , 2.3 - 14.2 , p = 0.00 ) . Survival among patients who received intravenous fluids was 3.9 times more likely than those who did not ( p = not significant ) . Average on-scene times for patients who had ETI or intravenous fluids were not significantly longer than those who had BVM or no intravenous fluids . CONCLUSION ALS procedures can be performed by paramedics on major trauma patients without prolonging on-scene time , but they do not seem to improve survival Background —Limited data are available on the impact of  prehospital thrombolysis ( PHT )  in the “ real-world ” setting . Methods and Results —Of 443 intensive care units in France , 369 ( 83 % ) prospect ively collected all cases of infa rct ion ( ≤48 hours of symptom onset ) in November 2000 ; 1922 patients ( median age , 67 years ; 73 % men ) with ST-segment – elevation infa rct ion were included , of whom 180 ( 9 % ) received intravenous thrombolysis before hospital admission ( PHT ) . Patients with PHT were younger than those with in-hospital thrombolysis , primary percutaneous interventions , or no reperfusion therapy .  Median time from symptom onset to hospital admission was 3.6 hours for PHT , 3.5 hours for in-hospital lysis , 3.2 hours for primary percutaneous interventions , and 12 hours for no reperfusion therapy . In-hospital death was 3.3 % for PHT , 8.0 % for in-hospital lysis , 6.7 % for primary percutaneous interventions , and 12.2 % for no reperfusion therapy . One-year survival was 94 % , 89 % , 89 % , and 79 % , respectively . In a multivariate analysis of predictors of 1-year survival , PHT was associated with a 0.49 relative risk of death ( 95 % CI , 0.24 to 1.00 ; P=0.05 ) . When the analysis was limited to patients receiving reperfusion therapy , the relative risk of death for PHT was 0.52 ( 95 % CI , 0.25 to 1.08 ; P=0.08 ) . In patients with PHT admitted in ≤3.5 hours , in-hospital mortality was 0 % and 1-year survival was 99 % . Conclusions —The 1-year outcome of patients treated with PHT compares favorably with that of patients treated with other modes of reperfusion therapy ; this favorable trend persists after multivariate adjustment . Patients with PHT admitted very early have a very high 1-year survival rate BACKGROUND Respiratory distress is a common symptom of patients transported to hospitals by emergency medical services ( EMS ) personnel . The benefit of advanced life support for such patients has not been established . METHODS The Ontario Prehospital Advanced Life Support ( OPALS ) Study was a controlled clinical trial that was conducted in 15 cities before and after the implementation of a program to provide advanced life support  for patients with out-of-hospital respiratory distress . Paramedics were trained in st and ard advanced life support , including endotracheal intubation and the administration of intravenous drugs . RESULTS The clinical characteristics of the 8138 patients in the two phases of the study were similar . During the first phase , no patients were treated by paramedics trained in advanced life support ; during the second phase , 56.6 % of patients received this treatment .  Endotracheal intubation  was performed in 1.4 % of the patients , and intravenous drugs were administered to 15.0 % during the second phase . This phase of the study was also marked by a substantial increase in the use of nebulized salbutamol and sublingual nitroglycerin for the relief of symptoms . The rate of death among all patients decreased significantly , from 14.3 % to 12.4 % ( absolute difference , 1.9 % ; 95 % confidence interval [ CI ] , 0.4 to 3.4 ; P=0.01 ) from the basic-life-support phase to the advanced-life-support phase ( adjusted odds ratio , 1.3 ; 95 % CI , 1.1 to 1.5 ) . CONCLUSIONS The addition of a specific regimen of out-of-hospital advanced-life-support interventions to an existing EMS system that provides basic life support was associated with a decrease in the rate of death of 1.9 percentage points among patients with respiratory distress STUDY OBJECTIVE To compare outcomes of patients with acute cardiac illness transported by ambulance for whom prehospital care was provided by emergency medical technician-paramedics ( EMT-Ps ) or EMTs trained in defibrillation ( EMT-Ds ) .  DESIGN A prospect i ve chart review carried out over 3.5 years . SETTING The Hamilton-Wentworth region of Ontario , Canada , which covers 1,136 km2 and includes five receiving hospitals . PARTICIPANTS We prospect ively identified 8,720 potentially eligible patients from approximately 30,000 who presented to the ambulance service . We review ed hospital charts to confirm eligibility . The group of 8,720 patients yielded 3,066 patients with acute cardiac illness who met all other eligibility requirements . We excluded patients in cardiac arrest . RESULTS Incidence of myocardial infa rct ion ( MI ) , length of hospital stay , and mortality were evaluated . Analysis was performed with chi 2 tests for association , linear regression , and logistic regression . Of the eligible patients who received prehospital EMS care , 783 sustained MIs . The proportions of people discharged alive with the diagnosis of MI did not differ between crew types ( P = .16 ) . Average hospital stay was 13 days in both groups for patients with the discharge diagnosis of MI ; hospital stay ranged from 9 ( EMT-D ) to 11 days ( EMT-P ) for any patient with a discharge diagnosis other than MI . These values were statistically similar . The odds ratio of having had an MI after treatment by an EMT-D crew was 1.02 ( 95 % confidence interval , .86 to 1.21 ) compared with that for treatment by an EMT-P crew . CONCLUSIONS In an urban setting with short ( less than 10 minutes ) average transport times , the availability of prehospital paramedic care does not affect occurrence of MI , length of hospital stay , or mortality of patients presenting to the EMS system with cardiac illness BACKGROUND The Ontario Prehospital Advanced Life Support ( OPALS ) Study tested the incremental effect on the rate of survival after out-of-hospital cardiac arrest of adding a program of advanced life support to a program of rapid defibrillation . METHODS This multicenter , controlled clinical trial was conducted in 17 cities before and after advanced-life-support programs were instituted and enrolled 5638 patients who had had cardiac arrest outside the hospital . Of those patients , 1391 were enrolled during the rapid-defibrillation phase and 4247 during the subsequent advanced-life-support phase .  Paramedics were trained in st and ard advanced life support , which includes endotracheal intubation and the administration of intravenous drugs . RESULTS From the rapid-defibrillation phase to the advanced-life-support phase , the rate of admission to a hospital increased significantly ( 10.9 percent vs. 14.6 percent , P<0.001 ) , but the rate of survival to hospital discharge did not ( 5.0 percent vs. 5.1 percent , P=0.83 ) . The multivariate odds ratio for survival after advanced life support was 1.1 ( 95 percent confidence interval , 0.8 to 1.5 ) ; after an arrest witnessed by a byst and er , 4.4 ( 95 percent confidence interval , 3.1 to 6.4 ) ; after cardiopulmonary resuscitation administered by a byst and er , 3.7 ( 95 percent confidence interval , 2.5 to 5.4 ) ; and after rapid defibrillation , 3.4 ( 95 percent confidence interval , 1.4 to 8.4 ) . There was no improvement in the rate of survival with the use of advanced life support in any subgroup . CONCLUSIONS The addition of advanced-life-support interventions did not improve the rate of survival after out-of-hospital cardiac arrest in a previously optimized emergency-medical-services system of rapid defibrillation . In order to save lives , health care planners should make cardiopulmonary resuscitation by citizens and rapid-defibrillation responses a priority for the re sources of emergency-medical-services systems The object of the study was to identify the effect paramedics have on prehospital trauma care and evaluate their influence on outcome compared to that of ambulance technicians . A prospect i ve review of ambulance and hospital records was conducted over 2 years from 1 August 1993 to 31 July 1995 . The setting for the study was the Royal Infirmary of Edinburgh and its primary response catchment area served by the South-East 
    Output:
    
In cardiac arrest , early cardiopulmonary resuscitation and defibrillation are essential for survival , but prehospital ALS interventions have not improved survival .
Prehospital thrombolytic treatment reduces mortality in patients having a myocardial infa rct ion .
The majority of research into trauma favours BLS in the case of penetrating trauma and also in cases of short distance to a hospital .
In patients with severe head injuries , ALS provided by paramedics and intubation without anaesthesia can even be harmful .
If the prehospital care is provided by an experienced physician and by a HEMS organisation ( Helicopter Emergency Medical Service ) , ALS interventions may be beneficial for patients with multiple injuries and severe brain injuries .
Conclusions -ALS seems to improve survival in patients with myocardial infa rct ion and BLS seems to be the proper level of care for patients with penetrating injuries .
Some studies indicate a beneficial effect of ALS among patients with blunt head injuries or multiple injuries .
There is also some evidence in favour of ALS among patients with epileptic seizures as well as those with a respiratory distress