Perioperative Management for Patients with Mast Cell DiseasesWhile the incidence of hypersensitivity to anesthesia and surgical procedures in patients with mast cell diseases (mastocytosis and MCAS) is unknown, various non-specific triggers in the perioperative setting may cause mast cell degranulation, and thus immediate hypersensitivity. Therefore, the goal of all perioperative management is prevention of mast cell mediator release. This can be accomplished by careful history taking, excellent communication between the anesthesia and surgical staff, avoidance of all known and potential triggers of mediator release, and careful attention to management of perioperative mast cell degranulation and/or cardiovascular changes.1 Although perioperative complications due to mast cell mediator release in children with mastocytosis are rare, they are not unknown.2 Measures to prevent triggering mast cell degranulation in adults and children should be utilized whenever possible.Prevention also includes perioperative antianxiety medications to avoid precipitating mast cell degranulation; maintenance of a steady environmental temperature throughout the entire surgical experience; minimizing friction and mechanical trauma (i.e. tape, tourniquet use, etc.) near mastocytosis skin lesions; careful positioning of the patient, being mindful of possible osteoporosis or osteolysis; avoiding histamine releasing drugs such as atracurium and mivacurium; pre-treating to prevent nausea and vomiting; aggressive treatment of pain, which is a potent mast cell degranulator, including utilizing some acceptable forms of opioids (i.e. fentanyl); use of H1 and H2 receptor antagonists to maintain mast cell stability.1,3Ring and Messmer have developed a grading scale to describe clinical severity of perioperative immediate hypersensitivity in mastocytosis:1,4Usually Non-Life ThreateningGrade I: Mucocutaneous signs and symptoms onlyGrade II: Mild mucocutaneous signs, features which may be associated with cardiovascular and respiratory changes.Life-ThreateningGrade III: Cardiovascular collapse which may be associated with mucocutaneous and/or gastrointestinal signs, and/or bronchospasm.Grade IV: Cardiac arrestSpecific management of a mast cell degranulation event in patients with mast cell diseases includes stopping any suspicious drug being administered, discontinuation of anesthetic agents likely to cause vasodilation and negative muscular contractility, if possible, and early administration of epinephrine for Grade III and Grade IV reactions along with 100% oxygen and large volume fluid support.With these measures, patients with mast cell diseases can be prepared for surgery with a plan that includes preventing mast cell degranulation by identification of possible triggers, rapid recognition of degranulation when it does occur and immediate appropriate intervention.