ok, ok, j'ai peut-etre lu un peu vite... mais j'en ai discuté récemment avec mon interniste qui avait justement fait une revue dans UpToDate et envoyé une patiente au scan plutot que V/Q. Si je trouve un peu de temps, je ferai une petite recherche dans uptodate lors de ma prochaine garde là dessus.
Martin Pham Dinh HYPERLINK "mailto:[EMAIL PROTECTED]"[EMAIL PROTECTED] _____ De : [email protected] [mailto:[EMAIL PROTECTED] De la part de Alain Vadeboncoeur Envoyé : January 16, 2008 12:28 PM À : [EMAIL PROTECTED] Objet : URG-L: CT ou VQ Heu.... BMJ C'est une lettre, donc une opinion: When available and appropriate, lung perfusion scans should be considered the investigation of first choice for any young woman. Pregnant women with a family history of breast cancer or who have had previous computed tomography for pulmonary angiography may wish to elect for lung perfusion scans, despite the slightly higher risk to the fetus. Computed tomography is a valuable, but high dose, investigation. Although the overall risk is very small and usually completely outweighed by the benefits of obtaining a prompt diagnosis, it is still important to choose the technique that entails the least risk. BJR C'est un abstract, as-tu l'article complet, mais ça ressemble plus à un article de review?: Pulmonary embolism is the leading cause of death in pregnancy. Despite the difficulties in clinical diagnosis and the concerns regarding radiation of the fetus, the British Thoracic Society guidelines for imaging pulmonary embolism do not specifically address the issue of imaging for pulmonary embolism in this group. This communication discusses the difficulties of diagnosis and imaging pulmonary embolism in pregnancy and proposes a suitable imaging protocol. Clinical exclusion of patients from further imaging is recommended if the patient has a low pre-test probability of pulmonary embolism and a normal d-dimer. It is advised that all remaining patients undergo bilateral leg Doppler assessment. If this test is positive, the patient should be treated for pulmonary embolism; if negative, all patients should be referred for CT pulmonary angiography. Ideally, informed consent should be obtained prior to CT scanning. All neonates exposed to iodinated contrast in utero should have their thyroid function tested in the first week of life due to the theoretical risk of contrast induced hypothyroidism. Radiology C'est un sondage donc sans aucune donnée particulière... qui lui réfère à trois études, dont la seconde semble être plutôt un position paper qu'une étude: * Winer-Muram HT, Boone JM, Brown HL, Jennings SG, Mabie WC, Lombardo GT. Pulmonary embolism in pregnant patients: fetal radiation dose with helical CT. Radiology 2002;224:487492.HYPERLINK "http://radiology.rsnajnls.org/cgi/ijlink?linkType=ABST&journalCode=radiolog y&resid=224/2/487"[Abstract/Free Full Text] * Administration of Radioactive Substances Advisory Committee. Notes for guidance on clinical administration of radiopharmaceuticals and use of sealed sources. Chilton, United Kingdom: National Radiological Protection Board, 1998; 36. * Russell JR, Stabin MG, Sparks RB, Watson E. Radiation absorbed dose to the embryo/fetus from radiopharmaceuticals. Health Phys 1997;73:756769.HYPERLINK "http://radiology.rsnajnls.org/cgi/external_ref?access_num=9378651&link_type =MED"[Medline] Les 2 études datent de 2002 et 1997. Donc Rosen était à date... Mais il n'en a peut-être pas tenu compte. Il faudrait lire les études pour voir ce qu'elle valent. Ce que Martin Chénier va surement faire illico Alain _____ From: [email protected] [mailto:[EMAIL PROTECTED] On Behalf Of Bernard Mathieu Sent: 16 janvier 2008 12:02 To: [EMAIL PROTECTED] Subject: URG-L: CT ou VQ J'ai de la difficulté à gober les chiffres cités dans le BMJ. Je trouve l'approche de Rosen sensée. Dans le BMJ, on cite une "étude locale" qui a mené à des recommandations. Quelqu'un a-t-il des réponses de nos nucléistes "locaux"? Bernard Mathieu, MD Le 08-01-16 à 11:15, Martin Pham Dinh a écrit : Je ne suis pas convaincu que Rosen est à jour. Du moins, voici des références qui indiquent clairement que le CT offre une irradiation foetale moindre par rapport au V/Q HYPERLINK "http://www.bmj.com/cgi/content/full/331/7512/350?etoc"http://www.bmj.com/cg i/content/full/331/7512/350?etoc HYPERLINK "http://bjr.birjournals.org/cgi/content/abstract/79/941/441"http://bjr.birjo urnals.org/cgi/content/abstract/79/941/441 HYPERLINK "http://radiology.rsnajnls.org/cgi/content/full/240/3/765"http://radiology.r snajnls.org/cgi/content/full/240/3/765 Je commence toujours par un doppler car si +, pas besoin d'investigation supplementaire. Martin Pham Dinh HYPERLINK "mailto:[EMAIL PROTECTED]"[EMAIL PROTECTED] _____ De : [email protected] [HYPERLINK "mailto:[email protected]"mailto:[EMAIL PROTECTED] De la part de Alain Vadeboncoeur Envoyé : January 16, 2008 10:38 AM À : HYPERLINK "mailto:[EMAIL PROTECTED]"[EMAIL PROTECTED] Objet : URG-L: CT ou VQ Rosen donne des idées intéressantes sur ce sujet: How can I rule out pulmonary embolism in a pregnant patient without use of ionizing radiation? PE is the most common nontraumatic cause of death in pregnant women, so clinicians are justified to adopt a liberal rule-out PE approach to all pregnant women with dyspnea. Pulmonary V/Q scanning is safe in pregnancy and provides almost no risk to the fetus. A chest CT scan delivers about 250 mrad of energy, whereas the common threshold at which fetomaternal experts believe fetal teratogenicity becomes a concern is about 5 rad. The mother's abdomen can be shielded, but the fetus will still receive a small fraction of the 250 mrad. There is a rapidly growing body of literature that suggests that exposure of the young brain to even small amounts of radiation can produce subtle cognitive deficits later in life, and at present the long-term consequences of CT scanning of pregnant patients are unknown. It seems logical to try to rule out PE with the D-dimer in pregnant patients; if D-dimer is negative in a patient believed to be at low pretest probability, this excludes the diagnosis. Coagulation systems are hyperactive in pregnancy, elevating the circulating D-dimer concentration. The D-dimer concentration increases linearly with duration of normal pregnancy, and about 75% of all pregnant patients evaluated for PE have a D-dimer concentration greater than the abnormal cutoff of 500 ng/mL.[HYPERLINK "http://www.mdconsult.com/das/book/body/85842565-2/0/1365/252.html#4-u1.0-B0 -323-02845-4..50092-5--bib46"46] About 60% of healthy pregnant patients have a D-dimer less than 1000 ng/mL, however, and virtually all pregnant patients with a PE have a D-dimer greater than 1000 ng/mL. A reasonable interpretation of these data suggests the following approach. If the D-dimer concentration is less than 1000 ng/mL, and the patient meets the criteria in HYPERLINK "http://www.mdconsult.com/das/book/body/85842565-2/0/1365/250.html#4-u1.0-B0 -323-02845-4..50092-5--cetextbox2"Box 87-2 , the diagnosis of PE may be considered reasonably excluded, and pulmonary vascular imaging is not necessary. As an additional margin of safety, a negative venous ultrasound of the lower extremities excludes DVT and helps reduce the probability of PE by about half. V/Q scanning, if normal, excludes the diagnosis. A high-probability V/Q scan establishes the diagnosis, and heparin (which does not cross the placental barrier) can be initiated. If neither normal nor high probability, the V/Q scan is nondiagnostic, and further imaging (perhaps beginning with venous duplex ultrasound of the legs) is indicated. Alain Vadeboncoeur No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.19.5/1228 - Release Date: 16/01/2008 9:01 AM No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.19.5/1228 - Release Date: 16/01/2008 9:01 AM No virus found in this incoming message. Checked by AVG Free Edition. 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