A Retrospective Clinical Analysis Of Pulmonary Embolism First-visit Data

1.Backgroud and ObjectivesPulmonary embolism(PE) is defined as the obstruction of the pulmonary artery or a branch of it leading to the lungs by a blood clot,usually from the leg,or foreign material causing sudden closure of the vessel.The risk factors for PE include advanced age(≥40 years old),cancer,genetic predisposition,immobilization (especially in the hospital),pelvic or leg trauma,pregnancy,and surgery. Generally,clinical data such as clinical manifestation,chest film,ECG are nonspecific. However,when the first-visit-doctor faced these these nonspecific firsthand data,how would these data influence on the diagnosis of PE ? And why ? Furthermore, advanced age(≥40 years old) as one of the PE risk factors,are there any differences between the first-visit data of the young patients and aged patients with PE? What enlightenment can we draw from this ?This research will analyse these questions retrospectively in order to deepen understanding of PE.2.Objects and Methods:2.1 Objects63 patients with PE who were in hospital(Nanfang Hospital,Southern Medical University) during 2001-1～2008-4.2.2 Diagnostic criteria,inclusion and exclusion criteria Diagnostic criteria for PE:the patient should be diagnosed by at least one of the methods as follows:CT pulmonary angiography(CTPA),MR Pulmonary Angiography(MRPA),ventilation-perfusion lung scanning,selective pulmonary arteriography,echocardiography.Inclusion criteria:(1) Patients corresponding to the above diagnosis criteria;(2) data were intact.Exclusion criteria:(1) Patients who were not confirmed diagnosed by one of the above 5 methods;(2) data were not intact.2.3 MethodsPart One:Analysis of the causes of PE omission diagnosis and the misdiagnosed diseasesThe 63 patients were divided into two groups:the first-visit-diagnosed group(Group A,23 cases) and the first-visit-mistake group(Group B,40 cases).The differences of the risk factors,initial symptoms,diagnosis time,Wells score,the revised Geneva score,chest films(after onset and before confirmed diagnosis) and ECG(after onset and before confirmed diagnosis) between the two groups were compared.Analyse of the misdiagnosed diseases from the clinical point of view.Part Two:Comparision of the first-visit data between the young and aged patients with PE(1) The patients were divided into 2 groups:the young group(＜40 yrs.) and the aged group(≥40 yrs.).The differences of the clinical data,Wells score and the revised Geneva score between the 2 groups were compared.Analyse the diagnosis time of the two groups.2.4 Statistical treatment The results were analyzed by SPSS13.0.Normality test of measurement data were carried out.If the data accord with normal distribution,they would be presented as means±SD,and t test was conducted for comparison between the two groups.Data of skewed distribution are presented as median and interquartile, and WilcoXon rank sum test was conducted for comparison between groups. Categorical data are presented as numbers(percent),and x~2 test was conducted for comparison between groups.Diagnosis time of the young group and aged group were analysed by Kaplan-Meier estimator,and the significance was tested by Log-Rank test. P values＜0.05 were considered significant.3.ResultsPart One:(1) In Group A,recent operation,malignancy,long-term bedridden state,PE history and deep vein thrombosis(DVT) symptom were more commonly seen than in Group B,and the patients in Group B were more likely to combined with hypertension,smoking,diabetes mellitus and no secondary risk factors.Among them,recent operation showed significant difference between the two groups(x~2= 6.011,P=0.014)(2) DVT symptoms as intial symptoms in Group A(13cases,56.5%) was more common that in GroupB(12cases,30.0%),and showed significant difference(x~2= 4.291,P=0.038).(3) The patents in group B had significantly lower Wells score and revised Geneva scores than those in Group A[2.50(5.00) vs 6.00(6.00),Z=-3.296,P=-0.001;5.50(4.75) vs 12.00(9.00),Z=-3.187,P=0.001,respectively].(4) In group B,chest film in 22 of the cases(55%) were wrongly reported as pulmonary infection,and among them,15 were misdiagnosed as pneumonia.(5) In groups A and B,SIQⅢTⅢ/QⅢTⅢin ECG was found in 5(21.7%) and 0(0%)cases,and normal ECG in 2(8.7%)and 18(45.0%)cases,respectively,showing significant difference between the two groups(x~2=8.883 and 6.704,P=0.010 and 0.003,repectively). (6)The misdiagnosed disease were in sequence of pneumonia 37.5% (15/40),CHD 12.5%(5/40),AECOPD 7.5%(3/40),bronchitis 5.0%(2/40), left heart failure5.0%(2/40),pleuritis 2.5%(1/40),chest shingles 2.5%(1/40), others 20.0%(8/40).The clinical manifestations and auxiliary examination of the misdiagnosed disease were similar to PE,and the first-visit doctors did not differentiate carefully.Part Two:(1) The first-visit omission diagnostic rate of the young group(66.7%) was similar t that of the aged group(61.9%),and the differences had no statistical significance(x~2= 0.137,P=0.711).(2) The first-visit symptoms and the clinical scores of the two groups were similar.Th young group combined with less risk factors than the aged group,and the the difference had statistical significance(Z=—2.387,P=0.017).(3)The K-M curve of the diagnosis time of the two groups showed that the aged group were confirmed diagnosed more difficultly(Log-Rank test:x~2=3.585, P=0.058).4.ConclusionsPartⅠ:The cause of PE first-visit missed diagnosis mainly included:(1)First-visit doctors' low vigilance to some PE risk factors;(2)Some PE patients' atypical clinical manifestations;(3)First-visit doctors' excessive dependence on chest films reports and ECG;(4) First-visit doctors' lack of careful differentiation.The extension of normative PE diagnostic process should be reinforced.PartⅡ:The initial symptoms of the young and aged PE patients were similar,and they were both easily missed diagnosis.However,the aged patients combined with more secondary risk factors which often masked the PE symptoms,and this would make them more difficult to confirmed diagosis than the young patients after first-visit missed diagnosis.