Patients with hereditary C1 inhibitor deficiency are at elevated risk of angioedema attacks triggered by medical, surgical, or dental procedures, as well as other known attack-inducing events. Short-term prophylaxis before such exposures is recommended practice.

Clinical Scenario

A scheduled medical, surgical, or dental procedure — or anticipated exposure to another event known to precipitate angioedema attacks — in a patient with hereditary C1 inhibitor deficiency.

First-Line Prophylaxis Did Not Reach Its Target

Intravenous plasma-derived C1 inhibitor was used as first-line short-term prophylaxis, administered as close as possible to the start of the procedure. The target — no angioedema near the site of intervention within 48 hours — was not achieved. This protocol addresses what to do next.

Next-Step Treatment Approach

Alternative short-term prophylactic strategies exist for this situation. These include a recombinant C1 inhibitor option as well as a plasma-based alternative for circumstances where other agents are not available or appropriate. The complete evidence-based regimen — including agent selection, sequencing, and timing considerations — is in the full protocol.

References

DOI: 10.1111/all.15214

We recommend considering short-term prophylaxis before medical, surgical or dental procedures as well as exposure to other angioedema attack-inducing events.

This could be considered if intravenous pdC1-INH is not available.

Fresh frozen plasma (FFP) may be used for short-term prophylaxis, but it is not as safe as intravenous pdC1-INH concentrate and is a second-line agent because of the greater risk of blood-borne disease transmission and allosensitization.

View source ↗

When First-Line Pre-Procedure Prophylaxis Has Not Achieved Its Goal: Hereditary C1 Inhibitor Deficiency Before Scheduled Medical, Surgical, or Dental Procedures

References