A Prospective Observational Cohort Pilot Study of the Association Between Midazolam Use and Delirium in Elderly Endoscopy Patients

Dickson Lee; Fiona Petersen; Maurice Wu; Gwenda Chapman; Melanie Hayman; Kerrilyn Tomkins; Jeremy Fernando


BMC Anesthesiol. 2021;21(53) 

In This Article


One hundred twenty-two patients met the inclusion criteria and were deemed eligible for the study during the study period of 7 months. Contact was made with 102 patients and consent received from 58 patient and carer pairs. Of the consented participants, 15 patient-carer pairs were excluded from analysis due to their procedures being brought forward or carers being unable to be contacted within 24–48 h of the procedure. A further 3 patient-carer pairs were subsequently excluded as the patients were found not to have been administered midazolam (Figure 2). There were 22 (51.2%) female patients and 21 (48.8%) male patients. The mean age was 71.9 +/− 4.6 (Range: 65 years old – 85 years old). The average weight of patients was 86.1 kg +/− 22.4 kg (Range: 50 kg – 166 kg). Twenty-nine patients (72.5%) underwent colonoscopies, 5 (12.5%) patients underwent gastroscopies and 9 (22.5%) patients underwent combination colonoscopy and gastroscopy. Demographic data is reported in the Table 1.

Figure 2.

Flowchart of patient selection process

Forty patients received midazolam during their procedure. The dosage of midazolam received ranged from 1.0 mg to 4.0 mg with a mean dose of 1.73 mg +/− 0.7 mg. The mean mg/kg dose of midazolam was 0.021 mg/kg +/− 0.008 mg/kg, the range of mg/kg dosing was 0.012 mg/kg to 0.048 mg/kg. All patients in the study population received Propofol, either as a bolus dose or target controlled infusion. Thirty-seven (92.5%) patients received opioid medications concurrently; 26 (65.0%) patients received fentanyl, whilst 11 (27.5%) patients received alfentanil (Table 2).

No patients in the study population were found to have post-operative delirium 24–48 h after their procedure based on the FAM-CAM screening tool. This result was consistent across patients undergoing gastroscopy, colonoscopy and combined gastroscopy and colonoscopy procedures. There was an absence of postoperative delirium in all patients administered midazolam in the study population.