CathLabHub

CathLabHub complications toolkitcathlabhub.com/toolkit/contrast-reactionIn review, October 24, 2026

Recognize

The signs on the monitor, the image and the patient.

  • PatientMild: limited hives, itch, flushing. Moderate: diffuse hives, facial or laryngeal swelling, wheeze. Severe: shock, respiratory or cardiac arrest 1.
  • MonitorHypotension with tachycardia (not the slow pulse of a vasovagal reaction), falling saturation, rising airway pressure.
  • PatientA tight throat, hoarse voice, stridor or wheeze minutes after the first injections.
  • PatientDelayed skin reactions 6 to 12 hours later 2.

Act now

In the order the operator does them. The first three come first, whatever else is happening.

  1. Stop the contrast and call for help; anesthesia now if the airway is involved 1.
  2. Airway, oxygen, and lay flat with the legs up if hypotensive.
  3. Epinephrine early for bronchospasm, airway swelling or hypotension: IM 0.5 mg of 1 mg/mL, or IV in small boluses with the monitor on 31.
  4. Rapid fluid: 1 liter normal saline by pressure bag, repeated as needed 1.
  5. Repeat epinephrine for persistent shock or start an infusion 1.
  6. Then diphenhydramine, an H2 blocker and a steroid; they do not reverse shock or airway swelling 21.
  7. Beta blocked patient not responding: glucagon 1 to 2 mg IV over 5 minutes, then an infusion 1.
  8. Sources differ: IV epinephrine is 10 mcg boluses titrated to pressure in Kern, 0.1 mg slowly in the ACR manual, and 0.3 mg of 0.1 mg/mL repeated to 1 mg in Brilakis 132.

Equipment

From the complications cart. Linked items open in the equipment directory.

  • Airway cart, oxygen, suction and a tracheostomy trayKeep a tracheostomy tray available for laryngeal edema 1.Not in the directory yet.
  • Pressure bag for fluidsNot in the directory yet.
  • Iso osmolar contrastLower risk of immediate reactions than ionic low osmolar contrast, but more delayed skin reactions 2. Directory: Visipaque (iodixanol).

Drugs

Adult doses as the cited source gives them. Check your formulary and the label.

  • Epinephrine IM0.5 mg (0.5 mL of 1 mg/mL) in the thigh; repeat every 5 to 15 minutes as needed 3.
  • Epinephrine IV bolus10 mcg boluses (0.1 mL of 1 mg/mL or 1 mL of 0.1 mg/mL diluted to 10 mL, 10 mcg/mL) until the pressure holds, then 1 to 4 mcg/min 1.
  • Normal saline1 liter rapidly, repeat as needed 1.
  • Diphenhydramine25 to 50 mg IV 21.
  • H2 blockerCimetidine 300 mg IV, or ranitidine 50 mg IV over 15 minutes, where available 2.
  • Hydrocortisone or methylprednisoloneHydrocortisone 200 to 400 mg IV or methylprednisolone 125 mg IV 1.
  • AlbuterolInhaler or nebulizer for bronchospasm 1.
  • Glucagon1 to 2 mg IV over 5 minutes, then 5 to 15 mcg/min, for patients on beta blockers 1.

Who to call

The escalation ladder, first call first.

  1. Code team: for shock or arrest.
  2. Anesthesia: at once for any airway swelling, stridor or hypoxia 1.
  3. Second nurse: to draw up epinephrine and run fluids.
  4. Allergy: after recovery, for future contrast planning.

The bailout step by step

Severe reaction, the first five minutes 13

  1. Stop contrast; call the code team and anesthesia.
  2. Oxygen; legs up; two large IV lines.
  3. Epinephrine 0.5 mg IM now, or 10 mcg IV boluses on the monitor 31.
  4. Normal saline 1 liter fast by pressure bag 1.
  5. Repeat epinephrine; start an infusion of 1 to 4 mcg/min if the pressure needs it 1.
  6. Albuterol for wheeze; prepare for intubation if the voice or airway changes 1.
  7. Diphenhydramine and a steroid once the pressure and airway are secured 1.
  8. Glucagon if on a beta blocker and not responding 1.

Prevent

  • Ask about prior contrast reactions; a prior reaction carries up to a 60 percent chance of repeat 1.
  • Premedicate prior reactors: prednisone 50 mg 13, 7 and 1 hours before plus diphenhydramine 50 mg 1 hour before 23.
  • Emergency case in a prior reactor: hydrocortisone 100 mg IV as soon as possible before the procedure 2.
  • Shellfish allergy marks atopy only; it is not an iodine allergy 1.
  • Sources differ: Kern gives prednisone 60 mg the night before and the morning of the procedure 12.

After care and documentation

  • Observe for recurrence; monitored bed for moderate or severe reactions.
  • Record the agent, the reaction, the severity and the treatment in the allergy list.
  • Plan premedication and a different agent for the next exposure.

Practice

Emergency simulator cases in the Cath Trainer app. The link opens Cases; type the case number in the search box.

  • EMG-0003: Flushing, wheeze and a falling pressure after the first injections
  • EMG-0007: Hives and a falling pressure
  • EMG-0032: A tight throat minutes into the case

References

  1. Berg R, Lim MJ. Complications of percutaneous coronary interventions. In: Kern MJ, ed. The Interventional Cardiac Catheterization Handbook. 3rd ed. Saunders, Elsevier; 2013. Chapter 4.
  2. Brilakis ES. Manual of Percutaneous Coronary Interventions: A Step-by-Step Approach. Academic Press, Elsevier; 2021. Chapter 3, Medications.
  3. ACR Committee on Drugs and Contrast Media. ACR Manual on Contrast Media. American College of Radiology; current edition (treatment of acute reactions in adults; premedication).
  4. CathLabHub Cath Trainer app, emergency simulator: case library (cathlabhub.com/app, Cases).

Educational reference for cath lab teams, not medical advice and not a standard of care. Your local policy, the device instructions for use and current guidelines govern. Verify every dose before use. Printed from cathlabhub.com/toolkit/contrast-reaction. First version, in clinical review: an interventional cardiologist is checking every card before it is final. Every number cites its source on the card.