A case of intra-operative anaphylaxis to latex in a pulmonary artery catheter

Introduction

Perioperative anaphylaxis (POA) is a diagnostic challenge. We present a case of anaphylaxis to intravascular latex preceding aortic surgery.

Case Description

A 55-year-old man was admitted for aortic arch and valve repair. Upon insertion of a pulmonary artery (PA) catheter, he developed hypotension, hypoxemia with elevated airway pressures, and a non-urticarial rash without angioedema. Anaphylaxis was successfully treated with epinephrine, but surgery was canceled. The plasma tryptase levels were 15.8, 20.1, and 5.1 mcg/L at 40 minutes, 6 hours, and 10 days after the event, respectively. Eight weeks later, patient underwent skin testing with negative results to all perioperative medications and latex. Subsequent serum IgE-specific antigen testing was positive for latex and borderline positive for pholcodine, a surrogate for neuromuscular blocking agents (NMBAs). IgE was negative for morphine which argues against rocuronium-related anaphylaxis. Subsequent surgery was successful in a latex-free OR without NMBAs. The patient denied symptoms to latex balloons, condoms, or band-aids.

Discussion

The NAP6 reported zero confirmed latex-related anaphylaxis cases, likely due to decreased latex-use in the OR. Despite this decreased incidence, clinicians should continue to be aware of latex anaphylaxis. Latex exposures may not be apparent as in our patient who reacted to the balloon of a PA catheter. Our case adds to the five reported cases of anaphylaxis due to latex in a PA catheter balloon, all in patients with no previous history of latex allergy. The lack of standardized skin testing adds to the diagnostic complexity. We recommend both skin testing and IgE immunoCAPS in cases of POA.