ric assay D-Dimer PLUS. The manufacturer and clinical experi-ence indicates that using the test with a cut off for a negative testset at 0.192 ng/l produces sensitivity (negative predictive value) of97%. Objective: The aim of our study was to review the diagnosisof thromboembolic disease (TD) (pulmonary embolism and deepvenous thrombosis) to see if the chosen cut off value of 0.192 ng/lis correct. Methods: We performed a retrospective review of allclinical records of patients treated in our emergency department(ED) in 2003, to identify all cases in which a D-dimer wasperformed, and determined clinical outcomes in those cases. Re-sults: We evaluated 64357 clinical records of patients who pre-sented to our ED in 2003. In 2778 patients the D-dimer wasordered and 1753 test results were � 0.192 ng/l. TD was diag-nosed in 119 patients (68 PE, 51 DVT). In all the patients with TDthe Wells score for clinical probability was performed. Among thepatients with PE, 1 had a D-dimer � 0.192 ng/l, while 3 patientswith DVT had a D-dimer lower than the cut-off. The patient withPE had a Wells score of 4 (intermediate clinical probability). All3 patients with DVT had a clinical probability intermediate orhigh. One of them reported leg symptoms beginning 45 daysbefore, so it is known that the D-dimer is not helpful in diagnosisin this case. The D-dimer assay performed in our laboratory withthe turbidimetric method (D-Dimer PLUS), had a sensitivity of98.5% in spite of a specificity of 6.7%. The negative predictivevalue was 99.6%. Conclusions: This study confirms that theD-Dimer PLUS assay is highly sensitive and reliable to safelyexclude the presence of a thromboembolism in the ED. Thenegative predictive value we obtained is even higher than thatrecently reported in the literature (by Vermeer HJ et al. Exclusionof venous thromboembolism: evaluation of D-Dimer PLUS forthe quantitative determination of D-dimer. Thromb Res 2005; 115:381–386.) Our data show a very low specificity, which suggests alow selectivity in deciding to order the test.

Non-invasive positive airway pressure ventilation and riskof myocardial infarction (MI) in acute cardiogenic pulmo-nary edema (ACPE): continuous positive airway pressure(CPAP) vs. non invasive positive pressure ventilation (NIV)G. Ferrari, G. De Filippi, A. Milan, F. Apra, F. Pagnozzi, A.Boccuzzi, P. Molino, F. Olliveri

Background: NIV and CPAP improve vital signs in the treat-ment of patients with ACPE, though a high incidence of mor-tality and MI were reported with the use of NIV. Objective: Toassess the efficacy and safety of CPAP and NIV in ACPE.Methods: We conducted a prospective, randomised trial. In-clusion criteria: severe dyspnea at rest, respiratory rate (RR) �30, PaOB2B/FiOB2B � 250 in FiOB2B � 0.5, muscularfatigue. PSV was started at 10 cmHB2BO and increased toreach a Vte of 6–8 ml/kg and to reduce RR; PEEP/CPAP wasstarted at 5 cmHB2BO and increased to keep SpOB2B � 92%;FiOB2B was started at 1 and decreased maintainingSpOB2B � 92%. End points: MI rate, improvement in bloodgas values, duration of ventilation, hospital length of stay(LOS), ETI and mortality rate. Results: 60 patients diagnosedwith ACPE were enrolled in the study; three patients wereexcluded. 57 patients were randomly assigned to receive CPAP

or NIV through face mask. At randomisation the two groupswere similar for all physiological parameters except forPaOB2B/FiOB2,B which was lower in the CPAP group (93 �27 vs. 120 � 5; p � 0.017). CPAP and NIV were applied for8.5 � 8.5 and 6.3 � 4.8 respectively (p � ns); no differencewas observed for length of stay in the HDU (4.3 � 2.3 vs.4.7 � 3.8 days respectively). After 1 hour of treatment, in bothgroups, a significant improvement was observed in pH,PaOB2B/FiOB2B, RR, heart rate, blood pressure, SpOB2B.Time course analysis also showed a significant increase in thesevariables without differences in CPAP and NIV. In hypercapnicpatients, the PaCOB2B improved significantly both in CPAPand NIV. No significant differences were observed in theincidence of MI: 12 patients had MI: 8(27%) in CPAP groupand 4(14%) in NIV group-p � 0.33. 7 patients after 1 hour ofCPAP failed to improve in RR or gas exchange and weretreated successfully with NIV. No difference in ETI was ob-served (p � 0.49): only 1 patient required endotracheal intu-bation in NIV group. No difference in mortality rate wasobserved: 6 patients died (2 in CPAP, 4 in NIV group-p �0.423). The underlying cardiovascular condition was fatal al-though the patients were successfully treated during the trialwith CPAP/NIV. Conclusions: Both CPAP and NIV result inearly improvement of physiological parameters. NIV doesn’timprove MI rate as previously observed. CPAP could be thetreatment of choice for ACPE, reserving NIV in cases of CPAPfailure.

Teaching disaster medicine to medical students: “learningby doing” is a useful tool.Ingrassia PL, Geddo A, Lombardi F, Calligaro S, Prato F,Tengattini M., Della Corte F.- Dpt of Anesthesia and CriticalCare-Universita del Piemonte Orientale-Novara-Italy

Background: In Italy the core curriculum for medical students,as indicated by the Ministry of Education and Research, in-cludes basic knowledge in Disaster Medicine (DM). Usuallythis content is part of the emergency medicine clerkship but inreality no University teaches it at all. During the academic year2004/05 the Universita del Piemonte Orientale offered a 24hour complementary course in DM. It was designed to teachbasic principles on how to deal with mass-casualty incident(MCI) or disasters as professional health providers. Coursedescription: Students receive formal lectures on the most im-portant topics in DM: (1) Definition of terms (disaster, emer-gency, mass casualty, vulnerable population, complex emer-gencies, terrorism, triage, disaster management, incidentcommand system, risk analysis, mitigation, and disaster med-icine); (2) Description of disaster management (myths andfacts in disasters, variables impacting outcome, resource allo-cation and medical care versus daily activity, phases, categoriesand classification of disasters); (3) Epidemiology of disasters(epidemiological impact of disasters in Europe, early history ofItalian disasters); and (4) Disaster management (mitigation indisaster planning, components of disaster management, SimpleTriage and Rapid Treatment (START) method). Students par-ticipate in tabletop exercises on medical management of MCI

Abstracts 245

scene and triage skills. They are also each assigned to a specificcase-victim, taught about predetermined victim-scenarios,evolving overtime and treatments performed, and finally theyacted as mock victims during a full scale MCI exercise of theV edition of the European Master in Diaster Medicine. Studentswere asked to evaluate the medical management of the exercisefocusing on predetermined objectives. A general evaluation ofthe medical management of MCI exercise was discussed in thedebriefing at the end of the course. Methods: 77 medicalstudents registered for the course: 24% (19) attended the 4PthPacademic year, 31% (24) the 5PthP year and 44% (34) the 6PthPyear. Students’ DM knowledge was evaluated at the begin-ning of the course, through a questionnaire and through sepa-rate surveys at the end. Half the questions were about basic DMprinciples and the latter half about medical management atdisaster scenes. The questions and the correct answers weremaintained in the two surveys, the wrong ones were changed.The impact of the triage method was evaluated using a tabletopcomputerised MCI scenario. This was tested before, immedi-ately after a lecture of START with slide presentation and at theend of the course. To assure confidentiality, participants sub-mitted surveys anonymously to an undisclosed member of thecourse instructor team. Results: 77 students completed thepre-test (PRE), 72/77 the two midcourse START triage skillassessment and 70/77 the post-test (POST) and final triageassessment. They also filled out a feedback form to evaluatetheir appreciation, or disagreement, of the course format and itscontent (the results are reported in another abstract presented).The mean POST score (66.7% correct) was not significantlyimproved compared with the mean PRE score (56.1% correct).Nevertheless a deeper investigation demonstrated that the meanPOST score of the questions about medical management atMCI scene (82.5% correct) improved considerably comparedwith the PRE score of the same questions (64.2% correct).Similar improvement was not evident for the questions aboutpure theoretical DM knowledge: mean PRE score was 47.9%versus 49.9% mean POST score. The mean immediate post-triage lecture score (94.6% correct) clearly improved comparedto the mean PRE score (67.8% correct) and the mean POSTscore was still high (95.1% correct). The over- and under-triagerates were significantly reduced before (11.3% and 20.8%respectively), immediate after the lecture (2.4% and 3% respec-tively) and after the full-scale exercise (2.4% and 2.5% respec-tively). No significant difference was found among the differentacademic years. Conclusions: There was no significant im-provement in the overall correct test answers. Nevertheless animportant increase in the knowledge of medical MCI manage-ment and more evidently in triage skills occurred. Being part ofa full-scale exercise as mock victims can better involve thestudents and stimulate their interest and enlarge their knowl-edge in DM. It can serve as an effective tool of teaching DM.Tabletop exercises can improve the medical management abil-ity and they are appreciated by the students. Physicians areexpected to establish disaster plans and coordinate the disasterresponse and care for disaster victims, yet few have the train-ing, knowledge or experience to do so. Therefore, we believeDM should be an essential part of the undergraduate curriculumof medical students.

Continuous Positive Airway Pressure (CPAP) vs. Non In-vasive Positive Pressure Ventilation (NIV) in Acute Cardio-genic Pulmonary Edema (ACPE): A Prospective Random-ized Multicentric Study

G. Ferrari, P. Groff, G. De Filippi, F. Giostra, M. Mazzone,G. Portale, N. Gentiloni Silveri, F. Apra, E. Vitale, F. Olliveri,Emergency Department, St. Giovanni Bosco Hospital, Turin,Policlinico St. Orsola Malpighi, Bologna, Policlinico A. Ge-melli, Rome, Policlinico St. Anna, Ferrara, Italy

Background: though non invasive airway positive pressure hasshown to be an effective treatment for ACPE, the literature stilllacks large randomised prospective multicentric studies that com-pares CPAP and NIV. AIM: assess the efficacy and the safety ofCPAP and NIV in patients with ACPE. Study Design: multicen-tric, prospective randomised. End points: intubation rate, resolu-tion time with the two methods, length of stay (LOS) in the ED,improvement in gas exchange, improvement in respiratory rate(RR) and heart rate (HR), mortality. Methods: inclusion criteria:severe dyspnea at rest, RR � 30, PaOB2B/FiOB2B � 250,muscle fatigue. PSV was started at 10 cmHB2BO and increased toreach a Vte of 6–8 ml/kg and to reduce RR; PEEP/CPAP wasstarted at 5 cmHB2BO and increased to keep SpOB2B � 92%,with a maximum level allowed of 10 cmHB2BO. Inspiratoryfraction of oxygen (FiOB2B) was included between 1.0 and 0.4.Results: 110 pts were enrolled, 4 were excluded because theydidn’t meet clinical/radiological inclusion criteria. 106 pts wererandomly assigned to receive CPAP or NIV. Mean age was76.8 � 10 and 77.4 � 10.1 years and SAPS II score was 40.4 �9.1 and 41.1 � 10.2 in CPAP and NIV respectively (p � ns).Initial mean values at randomisation were: CPAP: pH 7.22 �0.11, PaCOB2B 58.8 � 18.5, PaOB2B/FiOB2B 132.2 � 66.4,RR 32.7 � 6.03, HR 110.3 � 21.6, mean arterial pressure (MAP)125.1 � 28.8, SpOB2B 80.7 � 17.1. NIV: pH 7.25 � .010,PaCOB2B 58.2 � 19, PaOB2B/FiOB2B 159.6 � 96.4, RR36.5 � 5.7, HR 107.4 � 25.7, MAP 115.6 � 25.7, SpOB2B83.2 � 12.4. The two groups were homogenous for all physio-logical variables except for RR (p � 0.033). CPAP and NIV wereapplied for 6.8 � 6.82 and 7.29 � 5.11 hours respectively (p �0.184). No difference was observed for length of stay in the ED(CPAP: 63.9 � 51.2, NIV 60.9 � 8.4 hours — p � 0.881) and forhospital length of stay (CPAP: 13.2 � 1.9, NIV: 7.36 � 1.08 days— p � 0.375). After 1 hour of treatment, in both groups asignificant improvement was observed in gas exchange and inclinical-physiological variables: pH, PaOB2B/FiOB2B, COB2B,RR, HR, SpOB2B, map. Time course analysis also showed asignificant improvement over time of all these variables (p �0.001), no difference was showed between the two treatments(p � ns). 3 pts were intubated in the NIV group and none in theCPAP group: no statistical difference was observed (p � 0.243);all pts who underwent ETI were also COPD patients. No differ-ence was observed in mortality rate: 15 pts died - 4 in CPAP and11 in NIV group (p � 0.092). Both CPAP and NIV improved gasexchange in normocapnic and hypercapnic patients. Severe obe-sity didn’t affected outcome of CPAP of NIV in pts with ACPE.Conclusions: both CPAP and NIV result in early improvement ofgas-exchange and vital signs in pts with ACPE with no difference

246 The Journal of Emergency Medicine