potential sources of exposure

Potential sources of exposure. B.N., a 41-year-old woman who is a dental hygienist, has had several surgeries over the past 5 years because of a knee injury. She presents to the outpatient surgery department today for her last reconstructive surgery. Her past medical history indicates she had asthma as a child and had one occurrence of contact dermatitis. She tells you she has no known drug allergies.

You start B.N.’s IV and perform a saline flush. Within three minutes, B.N. states that her IV site itches, and a few minutes later, she begins to complain of itching around her neck and tightness in her throat.

Subjective Data

• States IV site itches
• States throat and neck feel tight and says, “I feel like I can’t breathe” 

Objective Data

• Vital signs: temp 98.8°F, heart rate 120, respiratory rate 32, blood pressure 100/60
• Oxygen saturation 85%
• Wheezing in all lung fields
• Restless
• Swelling at IV site

What is the apparent causative factor and what were potential sources of exposure?