{
  "abstract": "Introduction Sedation failure in diagnostic endoscopic ultrasound (dEUS) remains poorly characterised and understanding the demographic and clinical characteristics of patients who experience sedation failure with conscious sedation (CS) during dEUS is useful for risk stratification and the development of pre-procedural screening tools. We aimed to characterise patients experiencing CS failure during dEUS procedures at a tertiary referral centre.Methods A retrospective analysis was conducted on all patients undergoing dEUS, between April 2023 and September 2025. CS failure was defined as an incomplete procedure attributed to inadequate patient tolerance of sedation (agitation, paradoxical reaction, or intolerance to standard sedation regimens). Demographic data, comorbidities, sedation dosages, and clinical outcomes were extracted and described.Results Twenty-eight patients (1.8% of 1541procedures) experienced CS failure. The cohort was predominantly female (60.7%, n=17) with mean age 57.24 ± 15.9 years (range 21–88) compared with a mean age of 61.8 for the whole cohort. 21.4% were current smokers (n=6) and 10.7% ex-smokers (n=3). 28.6% reported active alcohol use (n=8). Complex comorbidities were prevalent, including chronic obstructive pulmonary disease, chronic kidney disease/end-stage renal disease, type 2 diabetes mellitus, and psychiatric conditions including depression. Despite high sedation doses - mean fentanyl 104.5 ± 43.6 mcg and mean midazolam 5.57 ± 1.8 mg - these patients failed to achieve adequate sedation. Procedural indications were predominantly pancreatic (n=15) and biliary pathology (n=8). Twelve of these patients went on to have an EUS under general anaesthesia (GA). Two patients went on to have a successful procedure with CS. The remaining patients were rediscussed in an MDT setting and planned for non-invasive surveillance. There were no post-procedure adverse events at 30-day follow-up.Conclusion In general, CS appears to be effective and well-tolerated for dEUS. Patients experiencing CS failure demonstrate a distinct clinical phenotype characterised by younger age, female predominance, and alcohol and smoking use history. Pre-procedural identification of these ‘hard-to-sedate’ characteristics may enable risk-stratified sedation planning, with consideration for alternative approaches including deep sedation or general anaesthesia to improve procedural success and patient safety.",
  "authors": [
    {
      "affiliations": [
        "Imperial College Healthcare NHS Trust, London, United Kingdom"
      ],
      "name": "Prateek Prasannan"
    },
    {
      "affiliations": [
        "Imperial College Healthcare NHS Trust, London, United Kingdom"
      ],
      "name": "Jahanzeb Malik"
    },
    {
      "affiliations": [
        "Imperial College Healthcare NHS Trust, London, United Kingdom"
      ],
      "name": "Iordanis Mylonas"
    },
    {
      "affiliations": [
        "Imperial College Healthcare NHS Trust, London, United Kingdom"
      ],
      "name": "David Zhang"
    },
    {
      "affiliations": [
        "Imperial College Healthcare NHS Trust, London, United Kingdom"
      ],
      "name": "Christopher Wadsworth"
    },
    {
      "affiliations": [
        "Imperial College Healthcare NHS Trust, London, United Kingdom"
      ],
      "name": "David Simon"
    },
    {
      "affiliations": [
        "Imperial College Healthcare NHS Trust, London, United Kingdom"
      ],
      "name": "Wafaa Ahmed"
    }
  ],
  "title": "P18 Characterisation of sedation failure in endoscopic ultrasound: a single-centre retrospective study",
  "uid": "958584ee-e31e-555b-a5ec-92e65888401f"
}