Latex sensitivity and the risk of a life-threatening anaphylaxis is an increasingly reported problem in pediatric urology. Patients with congenital defects such as spina bifida are
most prone, possibly because of repeated exposure to products containing
latex. Reactions occur most frequently within 30-45 minutes into the
operation. PREVENTIVE MEASURES Children with a history of spina bifida or with multiple exposures to latex should be referred for latex skin testing. Patients with a positive history for latex allergy should be identified prior to surgery so that precautions can be taken. The previous uneventful exposure to latex does not
preclude the possibility of a future reaction. PROPHYLAXIS The role of prophylaxis is controversial, but steroids
combined with H-1 and H-2 receptor blockers have been suggested for
administration preoperatively. LATEX ALLERGEN Latex products contain a rubber polymer and variable amounts of plant proteins, and it is thought that these residual protein impurities are the responsible antigens for the allergic manifestations. It is unclear whether the development of latex allergy directly correlates with the frequency of exposure or whether the various latex products have differences in their allergenicity. Latex allergy is usually manifested as a Type I IGE
antibody mediated reaction caused by mast cell degranulation and release
of vasoactive substances in a previously sensitized individual. PRECAUTIONS For patients with latex allergy, it is important to pay meticulous attention to avoiding exposure to latex-containing products by all hospital personnel and to make sure that appropriate documentation of latex allergy is included on the patient's charts and bracelets. Natural latex is found in gloves, anesthetic masks, breathing bags, blood pressure cuffs, tourniquets, syringes, multiple-dose vials, intravenous injection ports, and adhesive tape. Exposure may follow inhalation contact, mucus membrane or
intra-abdominal contact through contaminated glove powder, or direct
intravenous injection via a syringe or access port. PREVENTION This should be done by appropriate skin testing and explaining the risks of future surgical procedures and exposure to latex-containing material. The patient should also wear a medical alert bracelet and be handled with latex-free gloves during subsequent care. Gloves and/or glove powder in the examining room are sufficient to trigger an allergic response in some children. A latex-free anesthesia cart must be available in Operating Rooms and treatment areas. All equipment, including gloves, stopcocks, I.V. lines, multiple dose vials and adhesive tape, should be latex free. Ethylene oxide sterilized products should be avoided
because of reports of reactions from their use. SYMPTOMS All intraoperative anaphylaxis symptomatology is similar,
usually manifesting within 30-40 minutes into the procedure; and latex
anaphylaxis needs to be differentiated from other forms of intraoperative
cardiovascular collapse, including blood loss, tension pneumothorax, air
embolism, and cardiac and pulmonary problems. TREATMENT Treatment of cardiovascular collapse and bronchospasm should be immediate, with endotracheal tube ventilation and 100% oxygenation. Epinephrine can be administered I.V. or down the endotracheal tube with volume resuscitation, steroids, H-1 and H-2 receptor blockers, and possibly bronchodilators.
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