Summary: The increasing use of nonionic, low-osmolar contrast agents has led to a reactions and extravasation: Relationship to intravenous injection rates. With the selective use of contrast material, the adverse reaction rate was % and Contrast media reactions and extravasation: relationship to intravenous. The frequency of extravasation is not related to the injection flow rate. . Contrast media reactions and extravasation: relationship to intravenous injection rates.
This preparation prevents unwanted delays that might occur if someone had to sort through a larger emergency cart used predominantly for the treatment of cardiac arrest situations. This is particularly important since contrast reactions are infrequent occurrences and dosages may not be readily remembered. In addition to the proper medications, it is also important to have a variety of airway devices including bag valve mask devices for patients of all sizes and ages, nasal cannulas, oral airway kits, suction devices, and an oxygen source to provide proper early care in the treatment of many reactions Figure 2.
The most common contrast reaction is hives, which typically present as raised red wheels that may or may not be associated with pruritus. When hives are mild, they can simply be observed. However, patients who are more symptomatic may require oral PO or IV diphenhydramine at a dose of 25 to 50 mg.
Diphenhydramine is an antihistamine that has both anticholinergic and sedative effects.
Other, less common skin type reactions include angioedema and diffuse erythema. Angioedema results in localized swelling and erythema of the face around the eyes and mouth.
Patients with diffuse erythema often have orthostatic hypotension and a bright red appearance. If the patient is hypotensive or has a compromised airway, administering 0. Intravenous administration of medications is necessary in the hypotensive patient because medications given subcutaneously will not be mobilized into the intravascular system in these patients. The most common reaction involving the airway is bronchospasm, during which patients often develop tachycardia and dypsnea.
These patients often have a history of reactive airway disease. On auscultation, they usually have expiratory wheezing or both inspiratory and expiratory wheezing. Other airway-related reactions include laryngeal edema and pulmonary edema.
Patients who develop laryngeal edema often have difficulty speaking and swallowing. In contrast, patients with pulmonary edema are tachypneic, tachycardic, and diaphoretic.
On auscultation, rales are present in the bases.
Contrast media reactions and extravasation: relationship to intravenous injection rates.
Furosemide works as a potent diuretic. Reactions related to the vascular system predominantly include vasovagal reactions, cardiovascular shock, hypertensive crises, angina, and seizures. Vasovagal reactions and cardiovascular shock reactions both present with hypotension. These events are distinguished from each another in that vasovagal patients will be bradycardic and patients in shock will be tachycardic. Vasovagal reactions are often related to the needle puncture for IV placement or occur in the percutaneous biopsy procedures.
As previously stated, these patients are hypotensive and bradycardic. They are usually pale and have a decreased level of consciousness. Atropine has anticholinergic effects, and tachycardia occurs because of the paralysis of vagal control. Cardiovascular shock patients, on the other hand, are hypotensive and tachycardic. Patients have throbbing headaches and may be confused or nauseated.RISKS OF IODINATED CONTRAST MEDIA
Treatment with nitroglycerin, either in the sublingual tablet form 0. Furosemide may also be used in these patients. Nitroglycerin acts by relaxing vascular smooth muscle to decrease the blood pressure.
Nitroglycerin can also be used in patients who develop angina related to contrast administration. Finally, occasionally seizures can occur.
These are typically due to hypotension and are often self-limited. In most cases, patients require observation and supportive therapy only. If seizures persist, it can be helpful to administer a benzodiazepine such as 2 to 4 mg IV lorazepam, 5 mg IV diazepam, or 2. These drugs work to depress the central nervous system. A few additional situations may be encountered with the administration of contrast.
Patients will occasionally develop uncontrolled shaking known as rigors. These are often self-limiting.
Contrast media reactions and extravasation: relationship to intravenous injection rates.
If they persist, 25 to 50 mg meperidine has been found to be effective. The mechanism in the development of rigors as well as the reason for the effectiveness of meperidine is uncertain. As patients often have multiple tests scheduled for the same day and have been without food for many hours, patients may experience a hypoglycemic episode during which they feel weak, dizzy, or faint.
Patients usually require only a glass of juice to relieve their symptoms. Pediatric patients It is important to remember that pediatric patients may also have contrast reactions but may be unable to communicate their symptoms. Some risk factors for the occurrence of contrast extravasation are fragility of the venous network, venipunctures with metallic needles in comparison with plastic catheters, previously catheterized veins, multiple puncture attempts, impaired communication, extreme age, earlier or current chemotherapy or radiotherapy treatment 6, The nursing team active in computed tomography services plays an important role in the prevention, detection and treatment of adverse effects caused by iodinated contrast use.
At the research hospital, nursing examines the presence of risk factors for the occurrence of these reactions, provides for venous access and injects the contrast agent. Moreover, nursing professionals identify signs of systemic or local adverse reactions and implement the treatment needed for each case. Hence, the monitoring of adverse events deriving from tomographies is a tool to assess care delivery at this service and an important care quality indicator.
After the exam, patients were assessed for the occurrence of immediate adverse reactions deriving from the use of intravenous iodinated contrast during the 30 minutes after the radiopaque medium was administered. At the end of the data collection period, a sample of subjects was obtained, of whom received ionic iodinated contrast meglumine diatrizoate and received non-ionic iodinated contrast ioversol.
To study extravasation, only subjects who received the contract injection through peripheral venous access were included, totaling patients. Data were treated through descriptive and analytic statistics, using SPSS v. Next, in the results section, findings related to extravasation of the radiopaque medium were described separately, as this is a local adverse effect for which different sample subject inclusion and exclusion criteria were adopted.
Eighty-five percent of reactions were anaphylactoid, mainly characterized by pruritic papules and, less frequently, by face hyperemia and sneezing. Chemotoxic reactions only took the form of vomiting. Among the patients who received the non-ionic medium, only two cases presented an immediate adverse reactions, exclusively characterized by vomiting, corresponding to a reaction frequency of 1.
Intensity of all events was light, with signs and symptoms receding spontaneously, and In Table 1rates found in this study are compared with international references, showing no significant difference between these results and a Japanese research 1.
That study included feeling hot as an adverse reaction, with a frequency of 2.
Other authors 7 ignore not only feeling hot, but also the occurrence of vomiting. Therefore, when drawing a parallel with the results of that reference source, manifestations of vomiting were excluded. Result differences were significant for ionic iodinated contrast usage only; however, it should be highlighted that those researchers do not distinguish between light and moderate reactions, grouping them in one single category of adverse reactions.
This means that, although this study found a higher rate of adverse events when ionic contrast was used, these events were less severe, as they only referred to light reactions. Some studies ,8 have addressed the influence of the injection technique or contrast administration speed on the occurrence of adverse events, but these international research results are controversial.
In this study, we found that automatic contrast injection significantly increased the occurrence of adverse reactions, but only in the ionic group: When considering the influence of some client-related variables, literature 1 reports higher prevalence rates for all adverse reactions with both contrast types in the age range from 20 to 29 years, with a significant decrease in frequencies for each year added to the patient's age.
Hence, the younger the patient, the higher the probability of developing an immediate or late adverse reaction to iodinated contrast In fact, in this study, the frequency of reactions to the ionic medium decreased from the age of 30 onwards.
Another important characteristic of clients in this study is that Different studies 1,12 indicate that the rate of adverse reactions increases about three to five times in the presence of factors like a history of previous reaction to iodinated contrast, various allergies and asthma. In this research, no significant difference was found in anaphylactoid adverse event rates with ionic iodinated contrast usage between the group with and the groups without allergic antecedents: The volume of extravasated contrast ranged between 1 and 10 ml in All cases evolved favorably, without any complication deriving from these events.
One factor that was clearly associated with the occurrence of extravasation was the material used for the peripheral venipuncture. Usually, venous access is arranged immediately before the exam, using a caliber metallic needle for manual injection and a caliber plastic catheter for cases in which the radiopaque medium will be injected automatically through an injection bomb.
Review of common and uncommon contrast media reactions
Previously installed catheters are only used if they are in good conditions, that is, if established less than 24 to 48 hours ago, offering a good flow of 0. In order to avoid possible verification biases, extravasation frequency according to the type of venous access was calculated with a constant manual contrast injection technique, carried out by means of a metallic needle or plastic catheter. Extravasation rates corresponded to It is equally important to compare extravasation rates according to the radiopaque substance injection technique as, in recent years, the use of the injection bomb has been related with increased occurrence levels of this adverse event in international literature.
This relation is based on the fact that automatic injections administer the contrast in constant and stronger flows than manual injections In order to analyze extravasation frequency according to the injection technique, the type of plastic venous access was maintained constant, showing extravasation in 1. However, it is emphasized that patients who received the automatic injection were previously assessed by the nursing team and that their venous network was considered suitable to receive the contrast agent through an injection bomb, while patients with higher risk of extravasation received a manual contrast agent injection.
This may have provoked a deviation of risk cases to the manual injection group. No significant differences in extravasation rates were found between genders and age ranges. Venous network fragility was present in of the sample patients, five of whom presented extravasation.
This corresponds to a 5. Literature 2, about the occurrence of extravasation refers to research that used some criteria different from those used in this study, such as the exclusive use of plastic catheters, exclusive use of automatic injection and different criteria to select the research subjects.
In comparing the results of this study with international references, attempts were made to adapt results from the HCPA to the criteria used by different researchers, as shown in Table 2. Only one international study 8 presented a significantly lower percentage than results obtained at the HCPA, although extravasated contrast volumes ranged from 3 to ml, with a mean volume of 41 ml. Thus, although higher rates were found in this research, extravasated volumes were significantly lower.
This was fundamental for the non-occurrence of drastic consequences in the exposed patients. Moreover, other sources also mention higher extravasated volumes, ranging between 3 and ml 9or do not specify the extravasated volumes 2. The reduced extravasated volumes in this study, corresponding to less than 10 ml, is attributed to the fact that a nursing professional stayed at the patient's side during the injection, identifying signs of extravasation at an early stage and interrupting the contrast flow in time to prevent more severe complications in patients exposed to this event.
Another study 10 mentioned in Table 2 tested the efficacy of an automatic accessory device linked with the contrast injection site, which detects local extravasation, automatically interrupts the injection of the radiopaque medium and does not require the health professional's presence at the patient's side during the injection.
This research, carried out in Philadelphia, USA, presented the highest extravasation rate found in literature, with extravasated volumes ranging between 13 and 18 ml.
Moreover, during the study, false-positive cases occurred in 2. As to the study subjects, the fact that this sample exclusively consists of hospitalized patients suggests a higher rate of adverse events than in studies including outpatients.
Some conditions that are very common among hospitalized patients have already been associated with a two- to fourfold increase in chances for the occurrence of adverse reactions to radiopaque medium, such as exposure to surgeries, invasive procedures or regular medication intake during the five days before the exam With respect to immediate adverse reactions, this research considered vomiting, while international studies 1,7 exclude vomiting and include other symptoms, such as feeling hot and pain in the injection site.
In other words, study results can only be compared when samples in equivalent health conditions are used and when the same research subject inclusion and exclusion criteria are adopted. However, due to the lack of information produced in conditions similar to this study context, references were used to provide parameters that could indicate the adequacy or inadequacy of local results.
In this study, immediate adverse reactions to iodinated contrast occurred at a frequency of