Volume 7, No. 1 • Spring 1992

Latex Allergies Causing More Anesthesia Problems

Suzanne Parisian, M.D.

The FDA MEDICAL BULLETIN of July, 1991 carried a ‘Health Alert’ notifying clinicians of allergic reactions in patients and health care workers caused by exposure to latex-containing medical devices. The report was prompted by the growing number of reports of unanticipated severe reactions following exposure to latex-containing products and medical devices. Reported reactions have ranged from mild urticaria to full-blown systemic anaphylaxis. Latex is a component of many medical devices found in both the operating room and the hospital environment, including: surgical gloves, catheters, endotracheal tubes, anesthesia masks, catheter tips, iv administration sets and syringe barrels.

The exact etiology of the latex allergic response has not been elucidated. However, the water soluble proteins of latex appear to be the primary allergen. The FDA is interested in developing standard assays for measuring these proteins and it has issued an industry ‘guidance to manufacturers’ to try to reduce levels of leachable protein in latex medical devices.

Mention of an anaphylactic reaction during general anesthesia usually conjures up in the anesthesia provider’s mind a drug-related allergic reaction. However, it has been estimated in one study that as many as 10% of patients evaluated for a history of an intraoperative anaphylactic reaction have had an allergic reaction caused by exposure to a latex-containing medical device (1)

Some of the facts known about latex anaphylaxis risk are:

1. Health care workers, individuals with a history of atopic disease, or individuals with prior reactions to latex consumer products or medical devices appear to be at a higher risk for having intraoperative allergic reactions.

2. Patients can have an allergic reaction after having had prior uneventful anesthesia.

Repeated exposure to latex products has been postulated as an explanation for the apparent increase in sensitivity to latex. It has been reported’ that the groups showing the highest risk of developing a latex allergy were operating room personnel (7.5% risk for physicians, 5.6% risk for nurses) and dental personnel (13.7/. risk). These groups had a higher incidence than other hospital employees (1.3% risk) or the general population (0.8%). One common scenario describing a person with a potential latex allergy is that of the medical worker who, suspecting an allergy to gloves, switches glove brands frequently unless he/she finds a glove that can be tolerated. Rarely do these people seek diagnostic or allergy testing or consultation by a physician.

Another known population at high risk for developing intraoperative allergic reactions to latex is patients with a history of frequent exposures to latex during multiple surgical procedures and/or routine care of a dysfunctional bladder or colon. This includes patients with meningomyelocele, spina bifida, and other congenital abnormalities, especially those involving the genitourinary system. Approximately 18% 40% of spina bifida patients have an allergy to latex. (2) These patients are repeatedly exposed to latex via urinary catheters, barium enema tips, surgical gloves, intravenous tubing, and syringes used in their routine care.

Preoperative management of patients at high risk for a latex allergy is the same as for any other allergy. Foremost is the need to avoid exposure to known or strongly suspected allergens. Treatment protocols recommended by the CDC include combined administration of H2-blockers, corticosteroids, and diphenhydramine hydrochloride during the 24-hour period before and after all scheduled surgical procedures.(3) Therefore, it is imperative that attempts be made to appropriately screen patients preoperatively to identify high risk candidates. A thorough preoperative history should include questions about possible latex allergies. Patients should be specifically questioned about itching, erythema, swelling or wheezing after wearing latex medical or household gloves, during dental or medical exams where latex products were used, while using latex containing devices or even after inflating balloons. Patients with spina bifida, congenital genitourinary problems, and a history of multiple surgical procedures should be considered potentially at high risk for a latex allergy. Known latex allergic individuals should be encouraged to carry “MedicAlert’ type warnings.

Perioperative management of a latex allergy centers on avoidance of latex-derived products. These products include latex-containing gloves, old-style endotracheal tubes, certain airways, tubing, and catheters. Recommendations that have appeared in the literature to decrease latex exposure include using a Bain circuit with a plastic mask, plastic endotracheal tubes, glass syringes, fluids stored in plastic bottles, intravenous tubing free of rubber ports and administering drugs drawn up directly from glass ampules. All surgical gloves touching the patient should be non-latex. Within the anesthesia machine itself, it is not currently feasible to change the components made of latex such as the ventilator bellows.

During anesthesia, the symptoms of latex anaphylaxis present typically within 30 minutes (but can range from 10 to 290 minutes) following anesthesia inductions The symptoms of anaphylaxis to latex may not correlate with the administration of a drug. The CDC MORBIDITY AND MORTALITY WEEKLY REPORT of July 5, 1991 noted that the anaphylactic reaction to a latex containing medical device begins 30 minutes after the start of the general anesthetic and often prior to the surgical incision. The reaction can be life threatening, with symptoms progressing rapidly over 5 10 minutes. The medical management is the same as for any other allergic reaction. However, the symptoms have to be recognized as resulting from an allergic reaction. Inquiries received by the FDA reflect a growing concern about the mechanics of creating a latex-free environment within the operating suite. Presently, manufacturers are not required to routinely identify their products as containing latex. Therefore, when in doubt, operating room personnel must call individual product manufacturers for this information. Private corporations, health care personnel organizations such as the American Association of Nurse Anesthetists, and the FDA are trying to develop a protocol for the safe administration of anesthesia to the latex-sensitive patient.

The FDA is asking health professionals to report incidents of adverse reactions to latex or other materials used in medical devices. To report, an incident, call the FDA Problem Reporting Program, operating through the U.S. Pharmacopeia toll-free number: 800-638-6725. For questions about FDA activity related to latex sensitivity and anesthesiology, call Claudia Gaffey, M.D. or Suzanne Parisian, M.D., Office of Health Affairs, Center for Devices and Radiological Health, at (301) 427-1060.

For a single copy of a reference list on latex sensitivity, write to : LATEX, FDA, HFZ-220, Rockville, MD 20857.

Dr. Parisian is Medical Officer, Center for Devices and Radiological Health, Office of Health Affairs, U.S. Food and Drug Administration

References

1. Leynadier F, Pecquet C, Dry J. Anaphylaxis to latex during surgery. Anaesthesia. 1989; 44: 547-550

2. U.S. Food and Drug Administration Medical Alert. MDA91-1. Rockville, Maryland. March 29,1991

3. CDC. Anaphylactic reactions during general

anesthesia among pediatric patients United States, January 1990 January 1991. Morbidity and Mortality Weekly Report. 40:26 (July 5, 1991),437

4. Swartz JS, Gold M, Braude B, Dolovich 1. Gilmour R. Intraoperative anaphylaxis to latex: An identifiable population at risk. Canadian Journal of Anesthesiology. 1990; 37: S131