MONTEREY, CALIF. – A screening questionnaire with targeted replacement of latex-containing medical products dramatically reduces the risk of latex anaphylaxis among women undergoing cesarean delivery, but a latex-free policy appears to be the only surefire way to eliminate this risk entirely, according to one institution’s experience.
Investigators at the tertiary-care Hadassah Hebrew University Medical Center, Ein Kerem campus, Jerusalem, found that 2% of women undergoing cesarean delivery experienced latex anaphylaxis with the center’s usual procedures, involving use of latex products and no special screening.
The incidence was more than two-thirds lower, 0.6%, when the center implemented a screening questionnaire in elective cases to assess latex sensitivity and used latex-free gloves and urinary catheters in women who screened as potentially sensitive, Dr. Carolyn F. Weiniger reported at the annual meeting of the Society for Obstetric Anesthesia and Perinatology. However, it was even lower, 0%, when the center implemented a latex-free policy for all women undergoing cesareans.
An economic analysis favored use of the questionnaire when the probability of latex anaphylaxis during cesarean was less than 2% and use of the latex-free policy when the probability was greater than that. "The economic analysis was a sensitivity analysis, so it could be used outside of our setting for a wide range of ICU costs. You just need to decide what your ICU costs are," Dr. Weiniger commented in a poster discussion session.
"I think this [study] is very applicable to our practices. ... You can look at your practice and decide if your rate of latex anaphylaxis is greater than or equal to 2%," said session comoderator Dr. Katherine W. Arendt of the Mayo Clinic, Rochester, Minn. She asked the authors what the perceived barriers were to making delivery rooms latex free.
"The main problem is that latex-free gloves, when we started the study, were five times more expensive than regular latex gloves," Dr. Weiniger replied.
Additionally, rewinding a bit, centers must be aware that a problem even exists. "Have a high index of suspicion for latex anaphylaxis because the signs are very subtle. If you have a case of hypotension unexpectedly during surgery that doesn’t have an obvious cause, like bleeding," look into it further, she recommended in an interview.
Centers that do identify a problem should crunch their numbers. "You can use our sensitivity cost analysis, where you just plot your own cost of gloves and cost of an ICU bed, and work out whether you are above or below a cost-benefit position, whereby it would be cheaper for your institution to switch to latex-free gloves as opposed to using latex gloves," she elaborated. Those numbers can then be taken to management to make the case for a change in policy.
But the effort does not necessarily end there, according to Dr. Weiniger. "We knew that all cesarean sections should be done with latex-free gloves, but one patient was rushed to the main OR, and the message hadn’t gotten through, and she had latex anaphylaxis during emergency cesarean section when regular gloves were used. So we had to institute an educational program as well to make sure everybody knew about the policy," she said.
In the study of 1,569 parturients, the investigators analyzed the incidence of latex anaphylaxis among those undergoing elective cesarean delivery during four consecutive periods spanning 40 months.
In the baseline period (n = 460 women), the center followed usual procedures, with use of latex products and no special screening. In the second period (n = 302), it implemented a latex-free policy for cesareans. In the third period (n = 281), it discontinued the latex-free policy because of costs. And in the fourth period (n = 526), it implemented the screening questionnaire with targeted intervention as an alternative approach; the questionnaire contained items validated in previous studies with skin prick test results and/or serum latex IgE antibodies to have high sensitivity and specificity for detection of latex allergy.
Study results showed that the incidence of latex anaphylaxis (possible, probable, or definite) was 2% in the first period, 0% in the second period (P = .003 vs. first), and 0.6% in the fourth period (P = .015 vs. first), Dr. Weiniger reported.
In all, 15% of women completing a questionnaire during the period when it was used had suspected latex sensitivity on the basis of the results.
Women experiencing anaphylaxis received many verbal and written reminders to be evaluated at the center’s allergy clinic, but just 44% did so. All were found to be positive for latex allergy on skin prick testing.