Acute Reactions to CM Flashcards
Acute reactions can be categorized as either (1) or (2).
- allergic-like reactions
- physiologic
Allergic-like reactions mimic classic allergic reactions, such as those triggered by other drugs or allergens. However, the absence of a confirmed — (as seen in true allergies) differentiates them.
antigen-antibody immune response
Allergic-like reaction classification
Anaphylactoid
Allergic-like
Idiosyncratic
Mimic anaphylaxis but are not caused by an immune response
Anaphylactoid
Managed similarly to true allergic reactions
Allergic-like reactions
Likely independent of dose and concentration above an unknown threshold
Allergic-like reactions
These reactions arise due to the chemical and molecular properties of the contrast media rather than immune system involvement.
Physiologic Reactions
Physiologic Reactions
Mechanisms include:
Chemotoxicity
Osmotoxicity
Molecular binding
Molecular binding is usually seein on —
MRI
Treatment:
▪ Dose adjustment or using contrast agents with lower chemotoxic/ osmotoxic properties.
▪ Symptomatic relief
Physiologic Reactions
Frequently dependent on dose and concentration.
Physiologic Reactions
Damage of cells due to chemical component of CM
Chemotoxicity
Damage due to hyperosmolality
Osmotoxicity
Alterations of normal cells due to binding
Molecular binding
Categories of Acute Reactions to Contrast Media
Mild
Moderate
Severe
Signs and symptoms are self-limited without evidence of progression.
Mild
Mild
Allergic-Like Reactions
- Limited urticarial/ pruritus
- Limited cutaneous edema
- Limited “itchy”/ “scratchy” Throat
- Nasal Congestion
- Sneezing/ conjunctivitis/ rhinorrhea
CUNT CRS
Mild
Physiologic Reactions
- Limited nausea/ vomiting
- Transient flushing/ warmth/ chills
- Headache/ dizziness/ anxiety/ altered taste
- Mild hypertension
- Vasovagal reaction that resolves spontaneously
HAD A TV ML
Signs and symptoms are more pronounced and commonly require medical management. Some of these reactions have the potential to become severe if not treated.
Moderate
Moderate
Allergic-Like
- Diffuse urticarial/ pruritus
- Diffuse erythema, stable vital signs
- Facial edema without dyspnea
- Throat tightness or hoarseness without dyspnea
- Wheezing/ bronchospasm, mild or no hypoxia
TWEED
Moderate
Physiologic
- Protracted nausea/ vomiting
- Hypertensive urgency
- Isolated chest pain
- Vasovagal reaction that requires and is responsive to treatment
PH IV
Signs and symptoms are often life-threatening and can result in permanent morbidity or death if not managed appropriately.
Severe
Severe
Allergic-Like
- Diffuse edema, or facial edema with dyspnea
- Diffuse erythema with hypotension
- Laryngeal edema with stridor and/or hypoxia
- Wheezing/ bronchospasm, Significant hypoxia
- Anaphylactic shock (Hypotension+ tachycardia)
AL WED
Severe
Physiologic
- Vasovagal reaction resistant to treatment
- Arrhythmia
- Convulsions, seizures
- Hypertensive emergency
CHAV
Requires observation to confirm resolution and/or lack of progression but usually no treatment.
Mild
Patient reassurance is usually helpful
Mild
Clinical findings frequently require prompt treatment. These situations require close, careful observation for possible progression to a life-threatening event.
Moderate
Requires prompt recognition and aggressive treatment; manifestations and treatment frequently necessitate hospitalization.
Severe
Hypertensive emergency vy Hypertensive urgency
Hypertensive urgency
- Moderate; Physiologic
- BP slowly rises
Hypertensive emergency
- Severe; Physiologic
- Sudden spike in BP
Severe Reactions to Contrast Media
Cardiopulmonary Arrest and Pulmonary Edema
A sudden and complete cessation of effective cardiac activity and respiration, leading to the inability of the heart to pump blood and oxygenate vital organs.
Cardiopulmonary Arrest
Cardiopulmonary Arrest
Actions for Management
o Assume allergic-like cause unless proven otherwise.
o Initiate emergency management protocols, including:
- airway management
- CPR
- administration of anti-histamine and epinephrine
Accumulation of fluid in the lungs that interferes with gas exchange and breathing.
Pulmonary edema
Caused by increased pressure in the pulmonary capillaries due to compromised cardiac function (e.g., heart failure).
Cardiogenic Pulmonary Edema
Cardiogenic Pulmonary Edema is often seen in patients with —.
reduced cardiac reserve
Non-Cardiogenic Pulmonary Edema: Not related to heart function. Causes include:
o Allergic-like reactions: Capillary leakage due to an inflammatory response.
o Physiologic reactions: Direct effects of CM on pulmonary vascular permeability.
Pulmonary Edema
Actions for Management:
✓ Cardiogenic: Manage cardiac condition (e.g., diuretics, inotropes).
✓ Non-cardiogenic: Assume allergic-like and administer appropriate treatment (antihistamines, corticosteroids).
✓ Provide supportive care:
o Oxygen therapy or mechanical ventilation for severe cases.
o Fluid management.
Diuretics vs inotropes
Diuretics increase heart dunction
Inotropes aka betablockers decrease heart activities (relaxes)
Common allergic reaction to CM:
Hives (Uticaria)
Edema
Raised red bumps (welts) or splotches on the skin.
Hives (Uticaria)
Often very itchy, but patient might also feel burning or stinging. Mild reaction but needs further observation.
Hives (Uticaria)
A swelling condition due to accumulation of fluid and it affects the face, arms, and feet.
Edema
If seen during CM procedures, it is best to consult with a physician to determine whether to postpone or continue the procedure.
Edema
Equipment that assesses the patient’s CLINICAL STATUS includes
- Stethoscope
- Sphygmomanometer
- Pulse oximeter
Contact phone number of the (1) should be clearly posted within or near any room which CM is to be injected. If there is no (1), the emergency external phone number is to be used.
- local emergency response team
Local emergency response team
Physician
Respiratory Therapist
Nurse
Transport aid
The following minimum EQUIPMENT should be within or near any room in which contrast media is to be injected:
✓ Access to oxygen
✓ Defibrillator or automated external defibrillator (AED)
✓ Blood pressure and pulse monitor
✓ Pulse oximeter
✓ Stethoscope
ADA BPS
The following minimum MEDICATIONS should be within or near any room in which contrast media is to be injected:
✓ IM Epinephrine/ Epipen 1mg/1mL (auto injector or vials with needle and syringe for use)
✓ Inhaled short-acting beta-agonist (inhaler/ nebulizer)
✓ anti-histamine
AH BIM
Clinical Manifestations of Expected Side Effects
- A feeling of flushing or warmth
- Nausea and/or vomiting
- Headache
- Pain at the injection site
- Altered taste, may be metallic
WAN PH
Clinical Manifestations of a Vasovagal Reaction
- Pallor
- Cold sweats
- Rapid pulse
- Syncope or complaint of feeling faint
- Bradycardia
- Hypotension
CPR HBS
Clinical Manifestations of Mild Adverse Reaction
- Nausea, vomiting
- Headache
- Dizziness
- Shaking
Clinical Manifestations of a Moderate Adverse Reaction
- Bradycardia
- Hypertension or hypotension
- Dyspnea
- wheezing
- Patient complaints of feeling of throat closing (laryngeal edema)
Clinical Manifestations of a Severe Anaphylactic Reaction
- Dyspnea related to laryngeal edema
- Hypotension
- Seizures
- Cardiac arrhythmia
- Lack of patient response
- Cardiac arrest
Clinical Manifestations of Expected Side Effects
Radiographer’s role
- Inform pt before CM administration
- Slow the rate of the contrast infusion.
- Observe the patient closely and offer reassurance.
Clinical Manifestations of a Vasovagal Reaction
Radiographer’s role
- Stop the infusion of contrast medium.
- Place the patient in flat or Trendelenburg position.
- Notify the radiologist.
- Remain with the patient and offer reassurance.
Clinical Manifestations of Mild Adverse Reaction
Radiographer’s role
- Stop the infusion and notify the radiologist or radiology nurse.
- Remain with the patient and offer reassurance.
- Prepare to assist in the administration of an antihistamine or subcutaneous epinephrine.
Clinical Manifestations of a Moderate Adverse Reaction
Radiographer’s role
- Stop the infusion.
- Notify the radiologist and the radiology nurse.
- Call for the emergency team if symptoms progress rapidly.
- Remain with the patient and offer reassurance.
- Prepare to administer oxygen and intravenous medications.
- If the patient is in respiratory distress, place him in semi-Fowler’s position.
- Position patient who is vomiting in a position to prevent aspiration.
Clinical Manifestations of a Severe Anaphylactic Reaction
Radiographer’s role
- Call for emergency response team (Code Blue).
- Notify the radiologist and radiology nurse.
- Prepare to use AED
- Prepare to administer oxygen and intravenous medications.
What to do if extravasation occurs?
- Elevate POI to restrict blood flow
- Apply cold compress for 20 mins for vasoconstriction
3, Apply warm compress for vasodilation to allow increased flow rate of blocked CM