What is the diagnosis and management of anesthesia intolerance (Adverse reaction to anesthesia)?

From the Guidelines

Intolerance to anesthesia can occur in various forms and should be discussed with your healthcare provider before any procedure requiring anesthesia, with a focus on minimizing morbidity, mortality, and improving quality of life. If you've experienced previous adverse reactions to anesthesia, inform your anesthesiologist immediately as alternative medications can be used 1. Common manifestations of anesthesia intolerance include:

• Postoperative nausea and vomiting (PONV)
• Malignant hyperthermia
• Pseudocholinesterase deficiency
• Allergic reactions

For PONV, preventive medications like ondansetron 4mg IV, dexamethasone 4-8mg IV, or scopolamine patches can be administered. Malignant hyperthermia, a rare but life-threatening genetic condition, requires immediate treatment with dantrolene sodium (2.5mg/kg IV initially) and supportive care. Pseudocholinesterase deficiency causes prolonged paralysis after certain muscle relaxants like succinylcholine; alternative non-depolarizing agents should be used in these patients. True allergic reactions to anesthetics are uncommon but can range from mild rashes to severe anaphylaxis requiring epinephrine (0.3-0.5mg IM), antihistamines, and corticosteroids 1.

The management of suspected immediate perioperative allergic reactions should follow a modified Delphi consensus process, which covers areas such as differential diagnosis, management during and after anaphylaxis, allergy investigations, and plans for a subsequent anaesthetic 1. Genetic testing may be recommended if you have a family history of anesthesia complications. Always wear a medical alert bracelet if you have a known anesthesia intolerance, and ensure your complete medical history, including previous anesthesia experiences, is documented before any procedure.

In cases of suspected anaphylactic reactions associated with anesthesia, it is essential to recognize the reaction early and manage it optimally to avoid death or permanent disability 1. The initial management of anaphylaxis should follow the ABC approach, and adrenaline (epinephrine) is the most effective drug in anaphylaxis and should be given as early as possible. If anaphylaxis is suspected during anesthesia, it is the anaesthetist’s responsibility to ensure the patient is referred for investigation.

The diagnosis of anesthesia intolerance can be challenging, but a thorough medical history and physical examination can help identify potential causes. A collaborative approach between anaesthesiologists and allergists/immunologists is essential for the diagnosis and management of suspected perioperative allergic reactions 1. The use of local anesthesia, such as lidocaine, can be effective in reducing pain and discomfort during procedures, but alternative options, such as diphenhydramine or bacteriostatic normal saline, may be necessary for patients with sensitivity or allergy to lidocaine 1.

In summary, anesthesia intolerance is a complex condition that requires a comprehensive approach to diagnosis and management, prioritizing morbidity, mortality, and quality of life. A thorough medical history, physical examination, and collaboration between healthcare professionals are essential for providing optimal care. The most recent and highest quality study, published in 2019, provides a modified Delphi consensus process for the management of suspected immediate perioperative allergic reactions, which should be followed in clinical practice 1.

From the FDA Drug Label

ADVERSE REACTIONS Reactions to procaine are characteristic of those associated with other ester-type local anesthetics. A major cause of adverse reactions to this group of drugs is excessive plasma levels which may be due to overdosage, rapid absorption, inadvertent intravascular injection, or slow metabolic degradation A small number of reactions may result from hypersensitivity, idiosyncrasy, or diminished tolerance to normal dosage.

Central Nervous System Reactions: These are characterized by excitation and/or depression Restlessness, anxiety, dizziness, tinnitus, blurred vision, or tremors may occur, possibly proceeding to convulsions.

Allergic: Allergic-type reactions are rare and may occur as a result of sensitivity to the local anesthetic or to other formulation ingredients, such as the antimicrobial preservative chlorobutanol contained in multiple-dose vials

Factors influencing plasma protein binding, such as acidosis, systemic diseases which alter protein production, or competition of other drugs for protein binding sites may diminish individual tolerance. Plasma cholinesterase deficiency may also account for diminished tolerance to ester-type local anesthetics.

The diagnosis of anesthesia intolerance (adverse reaction to anesthesia) involves identifying the signs and symptoms of central nervous system reactions, such as restlessness, anxiety, dizziness, and tremors, which may proceed to convulsions. It also involves recognizing allergic-type reactions, which are rare and may occur due to sensitivity to the local anesthetic or other formulation ingredients.

• Key factors that may contribute to anesthesia intolerance include:
  • Excessive plasma levels due to overdosage, rapid absorption, or slow metabolic degradation
  • Hypersensitivity, idiosyncrasy, or diminished tolerance to normal dosage
  • Plasma cholinesterase deficiency
  • Factors influencing plasma protein binding, such as acidosis or systemic diseases
• Management of anesthesia intolerance involves:
  • Immediate countermeasures for acute adverse experiences related to the central nervous system and cardiovascular system
  • Monitoring of circulation and respiration, and constant observation of patients receiving regional anesthesia
  • Availability of resuscitative equipment and personnel for treating adverse reactions
  • Avoidance of concurrent use of certain drugs, such as monoamine oxidase inhibitors or tricyclic antidepressants, with local anesthetic solutions containing epinephrine or norepinephrine 2 3 2

From the Research

Diagnosis of Anesthesia Intolerance

• Adverse reactions to local anesthetics can be due to various factors such as allergic reactions, toxic reactions, or negative effects of vasoconstrictors contained within the local anesthetic solution 4.
• True allergic reactions to amide local anesthetics are extremely rare, but have been documented 5.
• Symptoms of IgE-mediated allergic reactions to local anesthetics include anaphylaxis, which is very rare 6.
• Diagnosis of local anesthetic allergy can be challenging, and dermatologic surgeons should be aware of the symptoms of anesthetic allergy and its mimickers 6.

Management of Anesthesia Intolerance

• Alternative methods for managing patients with local anesthetic complications include acupuncture, hypnosis, sedation, general anesthesia, and antihistamines as a substitute for local anesthetics 4.
• Diphenhydramine hydrochloride (Benadryl) can be used as a substitute for local anesthetics in patients with a history of "caine" allergy 7, 5.
• General anesthesia and postoperative pain management can be safely performed in analgesic intolerant patients with and without asthma using propofol, fentanyl, and vecuronium for induction, and sevoflurane or isoflurane for maintenance 8.
• A practical approach for diagnostic and therapeutic options for local anesthetic allergy includes being aware of the symptoms of anesthetic allergy and its mimickers, and having a plan for managing allergic reactions in clinical practice 6.