What are the causes of anesthesia intolerance?

From the Guidelines

Some individuals may not tolerate anesthesia due to several factors, including allergic reactions to anesthetics, which can range from mild rashes to life-threatening anaphylaxis, with muscle relaxants, latex, antibiotics, and induction agents being common causes of anaphylaxis or anaphylactoid reactions related to anesthesia 1.

Causes of Anesthesia Intolerance

The causes of anaphylaxis or anaphylactoid reactions related to anesthesia are listed in order of approximate frequency of occurrence, including:

• Muscle relaxants
• Latex
• Antibiotics, particularly b-lactam antibiotics
• Induction agents or hypnotics
• Opioids
• Colloids, particularly dextran, mannitol, or hydroxyethyl starch
• Blood products
• Others, including protamine, isosulfan blue dye for lymph node dissection, gelatin solution used for hemostasis, chlorhexidine, ethylene oxide, radiocontrast media, streptokinase, methylmethacrylate, chymopapain 1

Anaphylaxis and Anesthesia

Most reactions occur because of direct mast cell activation, but life-threatening reactions are usually caused by specific IgE 1. The shared tertiary or quaternary ammonium group results in cross-reactions among the muscle relaxants, and succinylcholine might be more likely to cause reactions caused by flexibility of the molecule facilitating the cross-linking of specific IgE on mast cell or basophil membranes 1.

Preoperative Considerations

Preoperative considerations, such as skin testing to specific dilutions of muscle relaxants, can be useful in determining the safest agent after a suspected reaction 1. Additionally, understanding the general nature of pediatric mastocytosis is important for care in peri-operative management, and special attention to position and to protection of pressure points has to be given to patients with mastocytosis during anesthesia 1.

Perioperative Management

Perioperative management of patients with mastocytosis should be comprehensive and take into account the increased risk of anaphylaxis, and routine skin testing to anesthetic drugs, muscle relaxants or opioids prior to anesthetics is an option, but data may be difficult to interpret 1. Furthermore, psychological distress, such as pre- and postoperative anxiety, may increase perioperative analgesic requirements and postoperative complication rates, and effective communication strategies, including attending a preoperative educational session, can successfully reduce patient anxiety and improve their perioperative experience 1.

From the FDA Drug Label

The majority of serious adverse effects, particularly those associated with oxygenation and ventilation, have been reported when midazolam hydrochloride is administered with other medications capable of depressing the central nervous system Administration of IM and IV midazolam to elderly and/or high-risk surgical patients has been associated with rare reports of death under circumstances compatible with cardiorespiratory depression In most of these cases, the patients also received other central nervous system depressants capable of depressing respiration, especially narcotics

Someone may not be able to tolerate anesthesia due to cardiorespiratory depression caused by the administration of midazolam with other medications that depress the central nervous system, especially in elderly and/or high-risk surgical patients or those receiving narcotics 2.

• Key factors that may contribute to intolerance of anesthesia include:
  • Concomitant use of central nervous system depressants
  • Age and health status of the patient
  • Dose and administration of midazolam
• Potential risks associated with midazolam administration include respiratory depression, airway obstruction, and hypoventilation 2.

From the Research

Reasons for Inability to Tolerate Anesthesia

• Obstructive sleep apnea syndrome (OSAS) can increase the risk of upper airways obstruction episodes when administered with benzodiazepines, such as midazolam 3, 4, 5
• The use of sedatives and anesthetics in patients with OSAS can lead to adverse respiratory effects, including impaired upper airway patency and decreased oxygen saturation 4
• Certain medications, such as midazolam, can cause life-threatening obstructive apnea and excessive sedation in patients with OSAS 5
• The administration of anesthesia can exacerbate underlying conditions, such as OSAS, and lead to complications during and after the procedure 3, 4, 5

Patient Factors

• Patients with OSAS may be more susceptible to the depressant effects of sedatives and anesthetics on the respiratory system 3, 4, 5
• The presence of other health conditions, such as cardiovascular disease, can increase the risk of complications during anesthesia 6
• Individual tolerance to anesthesia can vary, and some patients may be more prone to adverse effects 7

Precautions and Considerations

• A thorough presedation assessment, including patient history and physical examination, is essential to identify potential risks and complications 7
• Patients with OSAS should be closely monitored during and after the administration of sedatives and anesthetics 3, 4, 5
• Alternative treatment options, such as positive airway pressure therapy or oral appliances, may be considered for patients with OSAS who require anesthesia 6