What is the role of Benzodiazepines (BZDs) in surgical procedures?

From the Guidelines

Benzodiazepines, particularly midazolam, are a viable option for sedation in surgical settings due to their rapid onset and short duration of action, but their use should be carefully considered in light of potential side effects and the availability of alternative agents like propofol 1.

Key Considerations

• Midazolam is a commonly used benzodiazepine in surgery, with a rapid onset of 1-2 minutes and a duration of effect of 15-80 minutes 1.
• The initial intravenous dose of midazolam in healthy adults is 1 mg, with additional doses of 1 mg administered at 2-minute intervals as needed, but dose reduction is necessary in elderly patients or those with ASA physical status III or greater 1.
• Potential side effects of benzodiazepines include respiratory depression, especially when combined with opioids, hypotension, paradoxical reactions, and prolonged recovery in certain patient populations 1.
• Alternative agents like propofol may be preferred for sedation in mechanically ventilated adults after cardiac surgery, according to recent clinical practice guidelines 1.

Clinical Applications

• Benzodiazepines are valuable for reducing preoperative anxiety, facilitating induction of anesthesia, providing amnesia during procedures, and preventing awareness during surgery when combined with other anesthetic agents.
• Midazolam is particularly favored for preoperative sedation and procedural sedation due to its pharmacokinetic profile.
• Careful dose adjustment and monitoring are necessary to minimize the risk of adverse effects, especially in vulnerable patient populations.

Monitoring and Reversal

• Patients receiving benzodiazepines for sedation should be closely monitored for signs of respiratory depression and other adverse effects.
• Flumazenil (0.2 mg IV, repeated as needed up to 1 mg) is available as a reversal agent for benzodiazepine overdose, but its use should be guided by clinical judgment and careful assessment of the patient's condition.

From the FDA Drug Label

Maintenance Dose: Additional doses to maintain the desired level of sedation may be given in increments of 25% of the dose used to first reach the sedative endpoint, but again only by slow titration, especially in the elderly and chronically ill or debilitated patient Induction of Anesthesia: For induction of general anesthesia, before administration of other anesthetic agents. Individual response to the drug is variable, particularly when a narcotic premedication is not used. The dosage should be titrated to the desired effect according to the patient’s age and clinical status When midazolam is used before other intravenous agents for induction of anesthesia, the initial dose of each agent may be significantly reduced, at times to as low as 25% of the usual initial dose of the individual agents.

Benzodiazepines in Surgery: Midazolam can be used for induction of anesthesia and maintenance of sedation during surgical procedures. The dosage should be titrated to the desired effect according to the patient’s age and clinical status.

• Key considerations:
  • Slow titration is recommended, especially in the elderly and chronically ill or deilitated patients.
  • Individual response to the drug is variable, particularly when a narcotic premedication is not used.
  • Concomitant use with opioids may result in profound sedation, respiratory depression, coma, and death.
  • Monitoring of respiratory and cardiac function is required. 2 2

From the Research

Benzodiazepines in Surgery

• Benzodiazepines are used in surgery due to their anxiolytic, sedative, and amnestic effects 3
• However, evidence has shown an association between benzodiazepines and adverse neuropsychiatric effects 3
• The use of benzodiazepines in surgery has been evaluated in various studies, including a systematic review and meta-analysis that examined the risks and benefits of benzodiazepine use during the perioperative period 3

Benefits and Risks of Benzodiazepines in Surgery

• A systematic review and meta-analysis found that the use of dexmedetomidine or propofol instead of benzodiazepines may improve ICU outcomes, including shorter ICU length of stay and duration of mechanical ventilation 4
• Another study found that the use of oral benzodiazepines for periprocedural anxiolysis was safe and effective, with a low risk of adverse effects 5
• However, a study also found that patients who received benzodiazepines in the perioperative period had a higher risk of persistent benzodiazepine use, particularly those with a history of anxiety, depression, or substance use disorder 6

Use of Benzodiazepines in Specific Surgical Procedures

• A study evaluated the use of sedatives, analgesics, and neuromuscular blocking agents in adults receiving extracorporeal membrane oxygenation (ECMO) support, and found that patients received relatively low doses of sedatives and analgesics while at a light level of sedation on average 7
• Another study found that oral benzodiazepines were useful tools for periprocedural anxiolysis in outpatient dermatologic, plastic surgery, dental, and ophthalmologic procedures performed under local anesthesia 5

Key Findings

• The use of benzodiazepines in surgery is associated with both benefits and risks, and should be carefully evaluated on a case-by-case basis 3, 4, 6, 5, 7
• Alternative sedatives, such as dexmedetomidine or propofol, may be considered in certain situations to improve ICU outcomes 4
• Patients who receive benzodiazepines in the perioperative period should be closely monitored for signs of persistent use or adverse effects 6