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Iodinated contrast agents may be
Radiopaque contrast agents are often used in radiography and fluoroscopy, to distinguish boundaries between tissues of similar X-ray density. Most contrast agents containing iodine. Iodinated contrast agents may be Ionic Nonionic Ionic contrast media, the salts are hyperosmolar as compared to blood. Ionic contrast agent should be used either for myelographic investigations, nor for injections in which it into the spinal canal (neurotoxic risk side effects) or the bronchial tree could (danger of pulmonary edema). Nonionic contrast media are hypo-osmolar (but compared with blood still hyperosmolar) or iso-osmolar (same osmolarity as blood). Newer ionic contrast agents are now used routinely in almost all hospitals because they have fewer side effects. The most serious adverse reactions are allergic reactions contrast nephropathy (kidney damage after intravascular injection of a contrast agent). Allergic reactions contrast, the findings vary with the severity. Lightweight (z. B. coughing, itching, nasal congestion) default (eg. As breathlessness, wheezing, slight changes in heart rate or blood pressure) heavy (z. B. shortness of breath, heart rhythm disturbances such as bradycardia, convulsions, shock, cardiac arrest) The mechanism is anaphylactoid (anaphylaxis): Among the risk factors: A previous reaction to contrast media injected asthma allergies the treatment begins with the demolition of the contrast medium infusion. In mild or moderate reactions is diphenhydramine 25-50 mg i.v. usually effective. With stronger responses, the therapy depends on the type of reaction (including oxygen, epinephrine, i.v. liquid supply, possibly atropine – bradycardia). In order to exclude the risk of contrast agent response, imaging methods should be preferred for vulnerable patients that do not require iodinated contrast agents. but if a contrast agent is necessary, should be used non-ionic agents and before a pre-medication with prednisone (50 mg po 13 h, 7 h and 1 h prior to injection of the contrast agent) and diphenhydramine (50 mg po, or 1 hour prior to injection) perform , If patients need immediate imaging, should diphenhydramine 50 mg po them or iv 1 hour before the injection of contrast agent and hydrocortisone 200 mg i.v. every 4 hours will be given until the imaging is complete. Kontrastmittelnephropathie In contrast, serum creatinine starts at induced nephropathy usually within 24 hours after the administration of i.v. to increase contrast agents; the highlight is located between the 3rd and 5th day and it falls back to the initial value within 7 to 10 days. Some common risk factors include: Pre-existing renal insufficiency (creatinine increased) diabetes mellitus, particularly in patients with associated chronic kidney disease hypertension heart failure Multiple myeloma age> 70 years use of other nephrotoxic drugs dehydration in patients at risk for acute kidney injury after receiving an iodinated intravascular contrast agent, the following measures should be considered. A reduced dose of the contrast agent using an iso-osmolar agent hydration There are many liquid therapies; an example is the i.v. Administration of 0.9% saline solution of 1 ml / kg over 24 h, initiated a few hours before the procedure. Acetylcysteine ??can be given as premedication for patients at risk of developing nephrotoxicity, but the effectiveness is uncertain. Oral antihyperglycemic drugs such as metformin should for 48 h after i.v. Gift be retained in order to avoid an accumulation when a Kontrastnephrotoxizität occurs. (Editor’s note: procedure depends on ESUR Guidelines of the GFR ab) Because many protocols for dealing with contrast agents and their reactions are specific and are constantly updated, it is important to discuss the exact details with the radiology department.