1. Multi Center Controlled Clinical Trial to Evaluate the Impact of Advanced Life Support on Out-Of-Hospital Respiratory Distress Patients Stiell IG, Wells GA, Spaite DW, Nichol G, Nesbitt L, De Maio VJ, Lyver MB, Brisson D, Martin MT, Doherty J, Beaudoin T, Cousineau D Can J Emerg Med 2002;4(2):136 OBJECTIVES: There is little published evidence regarding the optimal EMS management of respiratory distress. Our study evaluated the impact of advanced life support (ALS) EMS programs on respiratory patient outcomes.
METHODS: This multicenter before-after controlled clinical trial was conducted in 20 communities (population 15,000 to 750,000) as part of the Ontario Prehospital Advanced Life Support (OPALS) Study, which evaluates the impact of EMS programs for multiple conditions. During the before phase, care was provided at the BLS-D level. During the after phase, ALS providers performed endotracheal intubation and administered nebulized and IV drugs. Data were collected from ambulance reports, centralized dispatch data, ED records and in-hospital records. Chi-square and Student's t-test analyses were performed. RESULTS: The 7,716 patients enrolled during the two 6-month BLS and ALS phases were well matched for clinical and demographic features and had these characteristics: mean age 74.0 (16-107), female 53.6%, EMS status 'severe/life threatening' 51.8%, mean RR 28, final hospital diagnoses: CHF 16.9%, COPD 16.3%, pneumonia 9.8%, asthma 5.7%, other cardiac 4.8%, CHF/COPD 3.4%, cancer 2.9%. During the ALS phase, patients received these EMS interventions: nebulized salbutamol 55.3%, IV furosemide 15.2%, SL NTG 9.6%, IV morphine 1.5%, intubation 1.2%. There was a 23.4% relative reduction in the primary outcome, overall mortality from the BLS to the ALS phase (15.4% vs. 11.8%; P<.001). This table compares other outcomes: Measurement BLS ALS P-Value EMS-judged 'improved' 24.6% 46.7% .001 ED mortality 1.2% 0.9% .001 ED intubation 4.9% 3.5% .001 CXR aspiration 4.4% 1.8% 0.001 LOS (days) 10.2 9.3 .05 Best CPC at discharge 42.6% 58.7% .001 CONCLUSIONS: This is the largest controlled trial of out-of-hospital respiratory distress patients and clearly shows important benefit from ALS programs for mortality and other outcomes. 2. Predicted Impact of Citizen CPR Training on Cardiac Arrest Survival Based on Location of Cardiac Arrest Vaillancourt C, Stiell IG, Wells GA, De Maio VJ, Nesbitt L, Martin M, Cousineau D. Can J Emerg Med 2002;4(2):144 OBJECTIVES: Bystander CPR rates are generally better in public places than residential locations. We sought to determine the potential impact of citizen CPR training on cardiac arrest survival, based on specific location of cardiac arrest. METHODS: We reviewed data prospectively collected within the Ontario Prehospital Advanced Life Support (OPALS) Study. The OPALS database includes a population-based cohort of adult out-of-hospital cardiac arrest cases in 20 communities with BLS-D and ALS paramedics. We merged the OPALS and Municipal Property Assessment Corporation databases to obtain precise description of cardiac arrest location. Data was analyzed using descriptive statistics with 95% CI and sensitivity analysis. RESULTS: From 1995 to 2000, there were 6,816 consecutive cardiac arrest cases. Cardiac arrest occurred most often in residential locations 85.8% (house 57.4%, apartment 22.5%, nursing home 6.0%) as opposed to public places 14.2% (store 3.4%, recreation Facility 2.1.%, Street 1.4%, office building 1.3%, shopping mall 1.1%). Overall survival rate was 3.8% (95% CI 3.4-4.3) and varied between 0.68% (0.38-0.98) and 18.5% (14.0-23.0) depending on location, witnessed status and bystander CPR rate. Assuming that better CPR technique could increase survival by 3%, increasing bystander CPR rates to 35% and 50% would result in overall survival rates and additional number of lives saved per year in residential locations and public places in the OPALS communities, respectively, of 5.38% (18, 3) and 6.19% (28, 24). Similarly, relative increase and absolute number of lives saved in specific residential locations would be, respectively: House 63.4% (12) and 63.3% (18), Apartment 30.2% (5) and 29.5% (8), Nursing Home 6.5% (1) and 7.2% (2). CONCLUSION: Citizen CPR training could significantly increase survival to cardiac arrest, especially in private houses and apartment buildings. An intervention focused at improving bystander CPR rates and quality in those locations should be developed. 3. Identification of High Risk Locations of Cardiac Arrest for Optimal Implementation of Public Access Defibrillation (PAD) Programs De Maio V, Stiell IG, Wells GA, Vaillancourt C, Spaite DW, Nesbitt L, Martin MT, Cousineau D Can J Emerg Med 2002;4(2):131 OBJECTIVES: Many agencies are promoting widespread availability of AEDs in public places despite a lack of evidence for the best locations for PAD. We attempt to identify high-risk cardiac arrest location to guide the optimal distribution of AEDs in our communities. METHODS: This was an analysis of a prospective cohort study of all adult, out-of-hospital cardiac arrests occurring before EMS arrival within the 20 communities of the Ontario Prehospital Advanced Life Support (OPALS) Study.EMS response included firefighter defibrillation, BLS-D and ALS paramedics. Case definitions followed the Utstein guidelines. The place of arrest was identified from a centralized dispatch database. Unique property type codes were identified from each address from the provincial property assessment roll and grouped into 26 location categories. Analysis was descriptive. RESULTS: From 1995-2000, there were 6,151 consecutive cardiac arrests occurring at 5,401 separate addresses. Private residences comprised 87% of these addresses and the remaining 13% were public locations. The number of addresses with multiple cardiac arrests during the study period include: = 2 arrests, 404 addresses; = 3 arrests, 123 addresses; = 4 arrests, 57 addresses; = 5 arrests, 30 addresses. Those sites with an average of one arrest per year (= 5 from 1995-2000) accounted for only 201 (3.3%) of all cardiac arrests. The number of separate addresses for each of these high-risk location categories include: nursing homes 16, apartments 8, stores/strip mall 3, college 1, office building 1, mobile-home park 1. CONCLUSIONS: Most cardiac arrests occur as isolated events in private residences. We identified few locations within 20 OPALS communities that may be amenable to PAD. Further study will evaluate the utility of providing PAD for each of the location categories. All communities considering public placement of AEDs should similarly identify high-risk sites to guide the rational deployment of these devices. 4. Longitudinal Analysis of Effect of Resuscitation on Health Related Quality of Life after Sudden Cardiac Arrest Huszti E, Nichol G, Wells GA, Stiell IG, Nesbitt L, Blackburn J Can J Emerg Med 2002;4(2):142 OBJECTIVES: The Ontario Prehospital Advanced Life Support (OPALS) Study is a large EMS trial that evaluates ALS interventions for out-of-hospital patients and conducts detailed measurements of cardiac arrest survivor outcomes. This study assessed novel methods of analyzing incomplete or missing longitudinal data related to health-related quality of life (HRQL). METHODS: This prospective cohort study included all adult out-of-hospital cardiac arrest patients treated in 20 cities with a mixed BLS-D/ALS EMS system. Patients were evaluated for the Health Utilities Index (HUI) Mark 3, which describes health on a scale from 0 (dead) to 1.0 (perfect health). Subjects were interviewed at 3, 6, 9 and 12 months after discharge and were subject to dropout and truncation. The Propensity Score Multiple Imputation (MI) method was used to estimate the propensity that a data element is missing. Imputed values are then generated from those observed values that have similar propensity scores. Finally, generalized linear models are applied to the complete data set to test for independent associations between response intervals and longitudinal HRQL. Secondary analysis considered the Predictive Mean MI method. RESULTS: Of 8,105 cardiac arrest patients (1995-2000), 418 (5.2%) survived to discharge and 342 (81%) completed at least one HRQL interview. The median HUI Score was 0.87 (IQR 0.71-0.95) and the majority of cases had a score exceeding 0.8. Bystander CPR (odds ratio 1.9; 95%CI 1.1-3.3) and age >80 (OR 0.3; 0.1-0.97) were associated with very good HRQL. Generalized linear regression found time to defibrillation was associated with better HUI scores (p value = 0.0465). CONCLUSIONS: This is the first study to apply MI methods to the analysis of longitudinal HRQL data and to demonstrate that shorter response intervals are associated with better HRQL in cardiac arrest. This increase in sample size due to imputation significantly improves the accuracy of the results in EMS research. 5. Management and Outcomes of Out-of-Hospital Seizure Patients Attended to by EMS Saginur M, Stiell IG, Nesbitt L, Martin MT, Brisson D, Cousineau D, Doherty J, Beaudoin T, Vaillancourt C, Spaite DW, Nichol G, Lyver MB, Field BJ, Munkley DP, Luinstra LG, Campeau T, Dagnone E Can J Emerg Med;4(2):127 OBJECTIVES: Little is known about the outcomes and diagnoses of seizure patients seen by EMS. This study describes the management, hospital disposition, and final diagnoses of these patients. METHODS: This health records review constitutes the seizure sub-study of the Ontario Prehospital Advanced Life Support (OPALS) Study, the largest prehospital study yet conducted. The OPALS Study will assess the impact of prehospital ALS on patient outcomes. This sub-study was conducted in a city of 750,000 with a BLS-D EMS system. Included, were all adult out-of-hospital seizure patients seen over a 6-month period. Data sources were ambulance call reports, centralized dispatch data, ED and in-hospital records. Seizure duration was defined as the total time of individual seizures plus inter-ictal periods not interrupted by regained consciousness (GCS>14). Analysis included descriptive statistics with 95% CIs. RESULTS: Of 154 suspected seizures, 129 were true seizure cases, with the following characteristics: mean age 46 (range 18-92), male 70%, seizure history 80%, generalized 90%, not transported 7%. Prehospital seizure activity ended prior to EMS arrival in 65% of cases and prior to arrival at ED in 78% Mean prehospital seizure duration was 20 minutes (range 1-220). ED records were available in 111 of 120 cases (92.5%): 33% received IV anticonvulsants and 6% were intubated. From the ED, 35% were admitted (ICU 5%), 62% discharged, and 3% left against medical advice. Admitted patients' median length of stay was 5 days (range 1-610), including 0.3 days in ICU. Overall survival was 97.5%. Discharge CPC scores were 'good' 50%, 'moderate disability' 9%, 'severe disability' 41%. Chronic epilepsy caused 78% of cases; new-onset seizure diagnoses were : tumor 4%, alcoholism 2%, trauma 2%, CVA 1.5%, other known 5%, and unknown 9%. CONCLUSIONS: This comprehensive review offers the first in-depth profile of prehospital seizure patients. These data are essential for the design of future studies of EMS seizure management. 6. Potential Impact of Public Access Defibrillation Based upon Cardiac Arrest Locations Valerie J De Maio, Ian G Stiell, George A Wells, Michael T Martin, Jeremy Doherty, Daniel W Spaite, Justin P Maloney, Graham Nichol, Donna Cousineau, David Brisson, Tony Campeau, Eugene Dagnone and the OPALS Study Group. Acad Emerg Med 2001;8(5):415 University of Ottawa: Ottawa, Ontario, Canada, Queens University: Kingston, Ontario, Canada,University of Calgary: Calgary, Alberta, Ontario, University of Western Ontario: London, Ontario, Canada, Niagara Regional Base Hospital: Niagara Falls, Ontario, Canada, Ontario Ministry of Health: Toronto, Ontario, Canada, University of Arizona: Tucson, AZ ABSTRACT Objectives: Community public access defibrillation (PAD) programs are becoming commonplace despite the fact that the results of the PAD Trial are not yet known. This study evaluated the potential impact of PAD programs based upon an analysis of out-of-hospital cardiac arrest locations. Methods: As part of the Ontario Prehospital Advanced Life Support (OPALS) Study, this prospective cohort study included all adult out-of-hospital cardiac arrests in 3 medium-sized cities. EMS response included firefighter defibrillation and ALS paramedics. Based upon review of ambulance reports and dispatch records, cases were classified into one of 23 pick-up locations and then grouped into 5 categories: small residential, large residential, streets/outdoor, small public buildings, and large public buildings. Data analyses included descriptive statistics and sensitivity analyses to estimate the impact of doubling and tripling survival rates on additional lives saved per year. Results: From 1995 to 2000, there were 1,373 consecutive cardiac arrests and characteristics included: mean age 68.6, male gender 66.5%, bystander witnessed 47.8%, bystander CPR 16.1%, fire first 74.6%, rhythm VF/VT 33.6%, median defibrillation response interval 5.1 minutes, survival to hospital discharge 3.7%. Cardiac arrest locations were: small residential 56.1%, large residential 27.8%, streets/outdoor 7.9%, small public buildings 3.4%, large public buildings 4.8%. The numbers of additional lives that would be saved per year in each location if the overall survival rates doubled and tripled, respectively, were: small residential 4, 8; large residential 2, 3; streets/outdoor 2, 4; small public buildings 1, 2; large public buildings 1, 3. Conclusions: Less than 5% of cardiac arrests occur in large public buildings and the potential for lives saved with PAD appears to be modest. EMS and public health directors should recognize the limited potential of PAD and not overlook other methods for improving cardiac arrest survival. 7. The Relationship between Out-of-hospital Cardiac Arrest Survival and Community Bystander CPR Rates Valerie J De Maio, Ian G Stiell, George A Wells, Michael T Martin, Daniel W Spaite, Graham Nichol, David Brisson, Donna Cousineau, Jeremy Doherty, Marion B Lyver, Brian J Field, Douglas P Munkley and the OPALS Study Group. Acad Emerg Med 2001;8(5):415 University of Ottawa: Ottawa, Ontario, Canada, Queens University: Kingston, Ontario, Canada, University of Calgary: Calgary, Alberta, Canada, University of Western Ontario: London, Ontario, Canada, Niagara Regional Base Hospital: Niagara Falls, Ontario, Canada, Ontario Ministry of Health: Toronto, Ontario, Canada, University of Arizona: Tucson, AZ ABSTRACT Objective: While recent data have re-emphasized the role of bystander cardiopulmonary resuscitation (CPR) in the chain of survival for out-of-hospital cardiac arrest, its importance has not been clearly quantified. The objective of this study was to measure survival as a function of community bystander CPR rates. Methods: This prospective cohort study included all adult, cardiac etiology, out-of-hospital cardiac arrests from Phases I and II of the Ontario Prehospital Advanced Life Support (OPALS) Study. Patients in the 20 study communities received a BLS-D level of care by EMS, but no ALS. Logistic regression (LR) identified adjusted CPR rates using covariates found to be independently associated with bystander CPR. Survival was then modeled using the adjusted CPR rates. The logistic equation was used to estimate community survival for incremental bystander CPR rates. Results: From 1991 to 1997, there were 343 (3.7%) survivors among 9,218 cases treated. The overall bystander CPR rate was 15.2%. LR analysis found the following factors associated with bystander CPR (odds ratios with 95% CIs): male sex 1.21 (1.05-1.39), age/10 yrs 0.83 (0.80, 0.87), non-winter season 1.20 (1.04, 1.38), witnessed arrest 2.39 (2.10, 2.73), VFVT rhythm 2.13 (1.88, 2.43). Hosmer-Lemeshow goodness-of-fit statistic 0.86 for 8 DF; area under ROC curve 0.70. The survival function, using the adjusted CPR rate and the defibrillation response interval, indicates the odds of survival with increasing CPR rate were 1.71 (1.61, 1.81) per 5% increase. The survival function predicts, for successive 5% increments: 1) survival rates, and 2) additional lives saved per year in the OPALS Study communities: 25% (6.3%; 41 lives), 30% (10.4%; 107 lives), 35% (16.7%; 208 lives), 40% (25.7%; 352 lives). Conclusion: Improved community bystander CPR rates are associated with dramatically increased out-of-hospital arrest survival in a predictable fashion. EMS and public health directors should focus significant efforts towards improving their community bystander CPR rate. 8. Stiell,IG; DeMaio,VJ; Wells,G; Nichol,G; Spaite,D; Ward,R; Martin,M; Blackburn,J; O'Brien,J for the OPALS Study Group. Predictors of Good Quality of Life in Out-of-hospital Cardiac Arrest Survivors. May 2000;7(5)425 (abstract). Objectives: To evaluate the prehospital factors associated with optimal quality of life for survivors of out-of-hospital cardiac arrest, within the Ontario Prehospital Advanced Life Support (OPALS) Study. Methods: The OPALS Study is a large EMS trial that evaluates BLS-D and ALS interventions for cardiac arrest, trauma, and respiratory distress in 20 communities. This prospective cohort sub-study included all adult out-of-hospital cardiac arrest patients during the rapid defibrillation or ALS phases of the OPALS Study (1995-99) and who survived to one year. Patients were evaluated for the Health Utilities Index (HUI) Mark 3, which describes health as a utility score on a scale from 0 (dead) to 1.0 (perfect health). Analyses included appropriate univariate tests and stepwise logistic regression to model HUI scores >0.80. Results: The 5,022 consecutive cardiac arrest patients had overall survival rates of 5.1% to hospital discharge and 4.0% to one year. This sub-study included 189 (93.6%) of 1-year survivors: mean age 64.0 (range 16-94), bystander-witnessed 60.0%, EMS-witnessed 24.6%, citizen-initiated CPR 34.4%, initial rhythm VF/VT 89.1%, response with defibrillator < 8 minutes 98.9%, and best CPC category 86.9%. The overall median HUI score was 0.88 (IQR 0.74-0.95) which compares well to age adjusted values for the general population (0.85). Logistic regression identified 3 factors independently associated with good quality of life and their odds ratios (95% CIs): male gender 2.3 (1.1-5.2), EMS-witnessed arrest 3.1 (1.4-7.2), and citizen-initiated CPR 2.6 (1.3-5.4) (Hosmer-Lemeshow goodness-of-fit statistic 0.57). Conclusions: This represents the largest known study of 1-year survivors and is the first to demonstrate that citizen-initiated CPR is strongly and independently associated with better quality of life for out-of-hospital cardiac arrest survivors. 9. Demaio,VJ; Stiell,IG; Wells,G; Spaite, D; Martin,M; O'Brien,J for the OPALS Study. Factors Associated with Field Pronouncement and Futile Resuscitation of Out-of-Hospital Cardiac Arrest Patients. Academic Emergency Medicine. May 2000;7(5) 509 (abstract). (back to top) Objectives: Many EMS programs have adopted termination of resuscitation policies for cardiac arrest in response to research establishing the futility of transport after unsuccessful advanced life support (ALS) measures in the field. This study evaluated out-of-hospital termination practices and determined predictors of unsuccessful resuscitation, as part of the Ontario Prehospital Advanced Life Support (OPALS) Study. Methods: This prospective cohort study included all adult, cardiac etiology, out-of-hospital cardiac arrest cases within 11 communities with established field pronouncement policies and prehospital ALS care. Case definitions followed the Utstein style. Univariate (c2 and t-test) and stepwise logistic regression (LR) analyses identified factors associated with field termination and overall non-survival to hospital discharge. Results: From 1995 to 1999, there were 978 (52%) field terminations among the 1,875 cases treated. Survival was 5.0% overall. LR analysis found factors independently associated with field pronouncement and their odds ratios (95% CI): age � 80 years 1.8 (1.4-2.3), unwitnessed arrest 2.2 (1.8-2.7), no citizen CPR 1.3 (1.0-1.8), non-VF/VT rhythm 3.1 (2.5-3.9), and successful intubation 1.5 (1.1-2.0). Non-survival was independently associated with: age � 80 years 3.0 (1.2-7.7), unwitnessed arrest 4.3 (2.2-8.3), defibrillation response interval > 8 minutes 8.5 (1.2-62.3), non-VF/VT rhythm 9.4 (4.7-18.8), and successful intubation 2.0 (1.1-3.7). Conclusion: This study demonstrates that field termination occurs frequently for unwitnessed arrests in elderly patients with non-VF/VT rhythms. Factors associated with futile resuscitation are age > 80 years, unwitnessed arrest, defibrillation response interval > 8 minutes, non-VF/VT rhythm, and successful intubation and could form the basis for evidence-based EMS field termination guidelines. 10. David A Petrie MD, V.J. De Maio (M Sc), I.G. Stiell (MD, M Sc), J. Dreyer (MD), M. Martin, J O'Brien for the OPALS Study Group. Factors Affecting Survival of Prehospital Asystolic Cardiac Arrest in a BLS-D System. Academic Emergency Medicine. May 2000;7(5) 509 (abstract). Objectives: Previous studies have shown a very low but meaningful survival rate in prehospital cardiac arrest with an initial rhythm of asystole. There may be, however, an identifiable subgroup in which resuscitation efforts are futile. This study identified potential field criteria for predicting 100% non-survival when the presenting rhythm is asystole in a BLS-D System. Methods: This prospective cohort study was a component of Phases I and II of the Ontario Prehospital Advanced Life Support (OPALS) Study, was conducted in 21 Ontario communities with BLS-D level of care, and included all adult arrests of presumed cardiac etiology according to the Utstein Style. Analyses included descriptive and appropriate univariate tests as well as multivariate stepwise logistic regression to determine predictors of survival to hospital admission. Results: From 1991 to 1997, 9,899 consecutive cardiac arrest cases were enrolled with these characteristics: male (67.2%), witnessed (44.7%), bystander CPR (14.2%), defibrillation response interval (DRI) < 8 minutes (82.0%), asystole (40.8%), PEA (21.2%), VF/VT (38.0%), and overall survival (4.3%). Among the 3,888 asystole patients, 9 (0.2%) survived to discharge and 4 of these were unwitnessed arrests with no bystander CPR. There were, however, no survivors if the DRI exceeded 8 minutes. Logistic regression indicated that independent predictors of survival to admission and their odds ratios (95% CI) were 'DRI in minutes' 0.87 (0.77-0.98) and 'bystander witnessed' 2.6 (1.5-4.4). Conclusions: In a BLS-D system, there is a very low but measurable survival rate for prehospital aysstolic cardiac arrest. DRI > 8 minutes was associated with 100% non-survival whereas unwitnessed arrests with no bystander CPR did not. These data add to the growing literature which will help guide ethical decision making for protocol development in EMS systems. Improved specificity in prehospital termination guidelines could lead to more efficient resource utilization and less exposure to occupational risk. 11. FEASIBILITY EVALUATION OF CHEST PAIN PATIENTS IN THE OPALS STUDY Easo J, Stiell I, Wells G, Spaite D, O'Brien J, Martin M, Kennedy D, for the OPALS Study Group, Division of Emergency Medicine and Clinical Epidemiology Unit, University of Ottawa, Ottawa Objectives: The Ontario Prehospital Advanced Life Support (OPALS) Study will be the largest prehospital study yet conducted and will evaluate the impact of prehospital ALS programs on the outcomes of cardiac arrest, trauma, and other patients. The purpose of this study was to assess feasibility and methodological issues required for a clinical trial of chest pain patients within the OPALS Study. Methods: This cohort study was conducted over a 6-month period in a city of 750,000 and included all adults transported with a primary complaint of chest pain to one of 5 hospitals. Data were collected from ambulance, dispatch, ED, and hospital records. Analyses included descriptive statistics with 95% CIs and univariate associations. Results: 905 consecutive patients were enrolled: mean age 65.8, female 52.7%, NTG prior to EMS arrival 48.1%. Hospital survival was 95.2% and the immediate adverse outcome rate 16.0% (ED MI 13.7%, ED lethal arrhythmia 2.6%, ED pulmonary edema 1.7%, ED hypotension 1.5%, EMS- witnessed cardiac arrest 0.3%). Lengths of stay, in days, were: hospital 8.6, special care unit 2.8, telemetry unit 3.7. Cardiac procedures performed: angiography 18.6%, angioplasty 4.8%, CABG 3.9%, pacemaker 1.2%. The overall survival rate was 95.2%; 71.9% rated "good" at discharge on the CPC scale. The ICD-9 based final diagnoses were: chest pain NYD 17.6%, MI 17.1%, unstable angina 14.6%, stable angina 9.5%, G.I. 8.8%, cardiac dysrhythmias 6.0%, respiratory 5.9%, cardiac other 5.2%. For the proposed clinical trial, a sample size of 13,000 would afford 80% power to detect a 1% difference in hospital survival and a 2% difference in the immediate adverse outcome rate. Conclusions: This comprehensive in-hospital review provides an in-depth profile of prehospital chest pain patients and was vital for the design and funding of the chest pain component of the OPALS study, which will evaluate the benefits of prehospital ALS. Presented at the Canadian Association of Emergency Physician's Annual Conference, in Halifax, June 11-14, 2000. --- URG-L Si vous avez plusieurs adresses email, vous pouvez les envoyer a Frederic Giroux a l'adresse [EMAIL PROTECTED] Un (ou des) alias pourront ainsi etre crees pour que vous puissiez envoyer des messages a travers la liste a partir de n'importe quel de vos alias. Autrement, les messages qui proviennent d'une adresse non-listee sont automatiquement rejetes.
