Remimazolam sedation

AF single shot ablations and DCCV

Dr M. Lovell, MB BS, BSc, PhD, FRCP

Remimazolam

Remimazolam - preperation

Reconstitution

Byfavo 20 mg - reconstitute with 8.2 mL NaCl 0.9% to give a final concentration of 2.5 mg/mL.

Before giving sedation - review:

  • Appropriate patient selection: BMI <35 and no severe sleep apnoea

  • Airway assessed

  • Baseline BP / ECG / SpO2 / respiratory rate

  • Oxygen and suction available

  • Bag-mask and airway adjuncts available

  • Defibrillator / ALS equipment available

  • Flumazenil available

  • Naloxone available if fentanyl used

Monitoring

  • Continuous: ECG and SpO2
  • Regular: BP and respiratory rate every 5 minutes

Warning

Use capnography if verbal contact is lost.

AF ablation - single shot

Standard patient - AF ablation

Patient criteria: <65 years, ASA I-II and ≥50 kg.

  1. Give fentanyl 25-50 micrograms IV - usually 50 micrograms.
  2. Wait 1-2 minutes.
  3. Give remimazolam 5 mg IV over 1 minute.
  4. Wait at least 2 minutes.
  5. Assess:
    • response to voice or touch
    • airway, respiratory rate, SpO2, BP
    • pain and movement

Higher-risk patient

This pathway applies if any of the following are present: ≥65 years, ASA III-IV, <50 kg, or frailty.

  1. Consider fentanyl 25 micrograms.
  2. Wait 1-2 minutes.
  3. Give remimazolam 2.5-5 mg over 1 minute.
  4. If a top-up is required, give 1.25-2.5 mg, allowing at least 2 minutes between doses.

Use the lower end of the dose range when several risk factors coexist.

Inadequate sedation

Give remimazolam 2.5 mg IV over approximately 15 seconds.

Wait before repeating

Wait at least 2 minutes before repeating. Do not give repeated rapid boluses.

If 5 doses within 15 minutes fail, stop and reassess the sedation strategy.

Inadequate analgesia

Remimazolam is not analgesia

If pain or distress persists, give fentanyl 25 micrograms IV, then reassess.

Aim for approximately 5 minutes or more between supplemental fentanyl doses.

Increasing opioid requirement should prompt reassessment rather than repeated escalation of fentanyl and remimazolam.

Elective DC cardioversion

  • No routine opioid required

Standard patient

Patient criteria: <65 years, ASA I-II and ≥50 kg.

  1. Give remimazolam 5-7 mg IV over 1 minute.
  2. Wait at least 2 minutes.
  3. Assess adequate sedation before shock.
  4. If sedation is inadequate, give 2.5 mg IV, then wait at least 2 minutes.

Higher-risk patient

For patients who are ≥65 years, ASA III-IV, or <50 kg:

  1. Give remimazolam 2.5-5 mg over 1 minute.
  2. If a top-up is required, give 1.25-2.5 mg.
  3. Wait at least 2 minutes between doses.

Respiratory depression or oversedation

Stop drugs

  1. Stimulate.
  2. Reposition the airway or apply a jaw thrust.
  3. Give oxygen.
  4. Use an airway adjunct.
  5. Provide bag-mask ventilation if required.
  6. Call for anaesthetic or resuscitation support.

Ventilation takes priority over reversal medication.

Flumazenil

For clinically significant benzodiazepine sedation:

  1. Give 200 micrograms IV over 15 seconds.
  2. If the response is inadequate after 60 seconds, give 100 micrograms IV every 60 seconds.
  3. The maximum dose is 1 mg.

Warning

Flumazenil does not reverse fentanyl. Continue monitoring after reversal.

Deeper than intended?

Stop and reassess if:

  • loss of verbal contact is sustained;
  • repeated airway manoeuvres are required;
  • ventilation is impaired; or
  • positive-pressure ventilation is required.