Overview

Definition:
-Latex allergy is an adverse immune reaction to proteins found in natural rubber latex, ranging from mild skin irritation to severe, life-threatening anaphylaxis
-In surgical settings, exposure can occur via gloves, catheters, and other medical devices
-It is a critical consideration for patient and staff safety.
Epidemiology:
-The prevalence of latex allergy in the general population is estimated to be 1-6%, but it is significantly higher in healthcare workers (up to 17%) and individuals with frequent exposure to latex products or underlying conditions like spina bifida or multiple surgeries
-Risk in surgical patients varies.
Clinical Significance:
-Latex allergy poses a serious risk during surgical procedures, potentially leading to intraoperative anaphylaxis, delayed wound healing, and requiring significant protocol modifications
-Prompt recognition and management are vital for preventing morbidity and mortality.

Clinical Presentation

Symptoms:
-Contact dermatitis: localized redness, itching, dryness
-Urticarial reaction: hives, localized swelling
-Respiratory symptoms: rhinitis, conjunctivitis, cough, wheezing, dyspnea
-Systemic anaphylaxis: hypotension, tachycardia, bronchospasm, angioedema, cardiovascular collapse.
Signs:
-Erythema and edema at contact sites
-Urticarial wheals
-Mucosal swelling
-Wheezing on auscultation
-Tachycardia
-Hypotension
-Signs of shock
-Decreased oxygen saturation.
Diagnostic Criteria:
-Diagnosis is based on clinical history of exposure and symptoms, confirmed by specific IgE testing (skin prick tests or in vitro tests)
-However, in surgical emergencies, immediate management is prioritized over definitive testing.

Diagnostic Approach

History Taking:
-Inquire about previous reactions to latex products (gloves, balloons, condoms)
-Document known allergies to foods like bananas, avocados, kiwi, and chestnuts, which can cross-react with latex
-Ask about occupational exposure in healthcare settings or frequent use of latex-containing items
-Assess for underlying conditions like spina bifida or atopy.
Physical Examination:
-Thorough skin examination for dermatitis or urticaria
-Assess respiratory status for wheezing or stridor
-Monitor vital signs closely for any signs of cardiovascular compromise: heart rate, blood pressure, oxygen saturation.
Investigations:
-Specific IgE testing (RAST or ImmunoCAP) for latex allergens is the gold standard for diagnosis when not in an acute setting
-Skin prick testing can also be performed by an allergist
-In an emergency, diagnosis is clinical, and treatment is initiated empirically.
Differential Diagnosis:
-Other causes of intraoperative hypotension (vasovagal, drug reactions, hypovolemia, sepsis)
-Other causes of rash or urticaria (drug eruptions, other contactants)
-Bronchospasm from other etiologies (e.g., asthma exacerbation)
-Other forms of anaphylaxis not related to latex.

Management

Initial Management:
-Immediate discontinuation of latex-containing products and substitution with non-latex alternatives
-If symptoms of anaphylaxis are present, initiate emergency treatment: administer oxygen, establish intravenous access, and prepare for adrenaline administration
-Alert the anesthesia and surgical teams.
Medical Management:
-For mild reactions (dermatitis): topical corticosteroids and antihistamines
-For moderate reactions (urticaria, rhinitis): oral antihistamines, possibly systemic corticosteroids
-For anaphylaxis: Intramuscular adrenaline (epinephrine) 0.5 mg (1:1000 solution), repeated every 5-10 minutes as needed
-Intravenous fluids for hypotension
-Nebulized bronchodilators for bronchospasm
-IV antihistamines and corticosteroids
-Consider glucagon for refractory hypotension.
Surgical Management:
-If the reaction occurs during surgery, the surgical procedure may need to be altered or postponed based on the severity and stability of the patient
-Ensure all instruments, drapes, and medical devices used are latex-free
-Surgical teams must be aware and use appropriate personal protective equipment
-Meticulous attention to airway management is crucial if bronchospasm is present.
Supportive Care:
-Continuous monitoring of vital signs, oxygen saturation, and cardiac rhythm
-Maintain airway and adequate ventilation
-Strict adherence to latex-free environment
-Post-reaction observation in a monitored setting until fully recovered
-Patient education on avoiding latex in the future.

Complications

Early Complications:
-Anaphylactic shock leading to hypoperfusion and organ damage
-Severe bronchospasm and respiratory failure
-Post-anaphylactic pulmonary edema
-Recurrent anaphylaxis
-Prolonged hypotension.
Late Complications:
-Skin sensitization with chronic dermatitis
-Psychological impact and anxiety related to future medical procedures
-Potential for delayed wound healing if severe inflammation occurs.
Prevention Strategies:
-Strict implementation of latex-free protocols in operating rooms and healthcare facilities
-Comprehensive staff training on latex allergy recognition and management
-Use of latex-free personal protective equipment (gloves, masks, gowns)
-Clear labeling of latex-containing products
-Preoperative screening for latex allergy in high-risk individuals
-Maintaining a latex-safe environment throughout the hospital.

Prognosis

Factors Affecting Prognosis:
-Severity of the allergic reaction
-Speed of diagnosis and treatment
-Patient comorbidities
-Promptness of switching to latex-free alternatives
-Effectiveness of airway management.
Outcomes:
-With prompt and appropriate management, most patients recover fully from latex-induced anaphylaxis
-However, severe cases can lead to significant morbidity or mortality
-Recurrent exposure can lead to sensitization and more severe reactions.
Follow Up:
-Patients with confirmed latex allergy require lifelong avoidance of latex products
-Regular follow-up with an allergist for ongoing management and education is recommended
-Patients should carry an allergy identification card
-For surgical patients, clear documentation in their medical records is essential for all future care.

Key Points

Exam Focus:
-Intraoperative anaphylaxis differential diagnosis
-Management of anaphylaxis (adrenaline dosage and routes)
-Importance of latex-free environments
-Cross-reactivity with foods
-High-risk patient groups.
Clinical Pearls:
-Always have a latex-free kit readily available in OR
-Consider latex allergy in any unexpected hypotension or bronchospasm during surgery
-Educate patients and staff proactively
-Cross-reactivity with certain fruits (banana, avocado, kiwi) is a key historical clue.
Common Mistakes:
-Delaying adrenaline administration in suspected anaphylaxis
-Failing to identify latex as the trigger in intraoperative emergencies
-Inadequate sterilization of equipment after suspected latex contamination
-Not thoroughly documenting latex allergy for future reference.